Cancer / en Researchers uncover new role for cell’s waste disposal system in spread of pancreatic cancer /news/researchers-uncover-new-role-cell-s-waste-disposal-system-spread-pancreatic-cancer <span class="field field--name-title field--type-string field--label-hidden">Researchers uncover new role for cell’s waste disposal system in spread of pancreatic cancer</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-10/group-pancreatic2.jpg?h=81d682ee&amp;itok=8gpGPZtC 370w, /sites/default/files/styles/news_banner_740/public/2024-10/group-pancreatic2.jpg?h=81d682ee&amp;itok=8iGv4MSx 740w, /sites/default/files/styles/news_banner_1110/public/2024-10/group-pancreatic2.jpg?h=81d682ee&amp;itok=FVxDwrIW 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-10/group-pancreatic2.jpg?h=81d682ee&amp;itok=8gpGPZtC" alt="&quot;&quot;"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-10-22T10:02:57-04:00" title="Tuesday, October 22, 2024 - 10:02" class="datetime">Tue, 10/22/2024 - 10:02</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>Associate Professor Leonardo Salmena, post-doctoral researcher Golam Saffi&nbsp;and former master’s student&nbsp;Lydio To investigated the role of a gene called INPP4B in pancreatic cancer’s ability to spread (supplied images)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/betty-zou" hreflang="en">Betty Zou</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/princess-margaret-cancer-centre" hreflang="en">Princess Margaret Cancer Centre</a></div> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> <div class="field__item"><a href="/news/tags/university-health-network" hreflang="en">University Health Network</a></div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>A preclinical study is revealing new insights into the molecular machinery that drives the aggressiveness of pancreatic cancer.</p> <p>The ability of pancreatic cancer to invade and spread to other parts of the body is a major factor in its poor prognosis, with an overall five-year survival rate of less than 10 per cent.</p> <p>“Pancreatic cancer cells are known to be very metastatic and that’s a big problem,” says&nbsp;<strong>Leonardo Salmena</strong>, an associate professor of&nbsp;pharmacology and toxicology&nbsp;in the Ƶ’s Temerty Faculty of Medicine.</p> <p>Salmena is the senior author of a study, <a href="https://rupress.org/jcb/article/223/11/e202401012/276895/INPP4B-promotes-PDAC-aggressiveness-via-PIKfyve" target="_blank">published in the<em>&nbsp;Journal of Cell Biology</em></a>,&nbsp;that investigates the role of a gene called INPP4B in pancreatic cancer’s ability to spread. Led by post-doctoral researcher <strong>Golam Saffi</strong>&nbsp;and former master’s student&nbsp;<strong>Lydia To</strong>, the team found that INPP4B exerts its tumour-promoting effects via a cellular organ called the lysosome.</p> <p>“Classically, the lysosome is a garbage disposal organelle where old and tired proteins and other organelles get degraded to be used for energy and other building blocks for the cell,” says Salmena.&nbsp;</p> <p>In most cells, lysosomes typically cluster around the nucleus. But in pancreatic cancer cells, the researchers found that INPP4B drove the lysosomes from the cell interior to the periphery, where these organelles fuse with the cell’s outer membrane. In doing so, the enzymes and other lysosomal factors responsible for breaking down cellular waste are dumped into the space surrounding the tumour cells.&nbsp;</p> <p>This space contains a network of proteins and molecules that provides crucial structural support to cells and tissues while also restricting a cell’s ability to move. The release of the lysosome’s protein-degrading contents into this extracellular space causes the stabilizing network to fall apart, thus making it easier for pancreatic cancer cells to migrate and invade other tissues.</p> <p>Crucially, Salmena and his team also identified the signalling pathway by which INPP4B drives the movement of lysosomes to the cell edge. INPP4B works with two other proteins – PIKfyve and TRPML-1 – to modify the lysosome’s surface structure and alter local calcium levels so that the organelle is propelled to the cell periphery.&nbsp;</p> <p>Based on these findings, the researchers are testing two experimental drugs that target TRPML-1 and PIKfyve in a preclinical model of pancreatic cancer. They are also studying how the release of lysosomal contents can change the immunological environment of the cancer cells, and what effects that might have on the immune system’s ability to respond to the tumour.&nbsp;</p> <p>Salmena first became interested in INPP4B when, during his post-doctoral research, he found that it was involved in breast cancer. Since then, he and his team have shown that the effects of INPP4B vary depending on the context.</p> <p>For example, in some breast cancer types, INPP4B behaves as a tumour suppressor whereas it has an activating role in other aggressive cancers like pancreatic cancer – which the Canadian Cancer Society expects&nbsp;to be the third leading cause of cancer death in Canada in 2024, with an estimated 6,100 people dying from the disease.&nbsp;</p> <p>Salmena and his colleagues later showed that among all cancers, INPP4B levels are highest in pancreatic tumours, and that high levels of the protein are associated with decreased overall survival in people with pancreatic cancer.</p> <p>The study was a collaboration between Salmena’s group,&nbsp;<strong>Roberto Botelho</strong>, a professor of chemistry and biology at Toronto Metropolitan University, and&nbsp;<strong>Steven Gallinger</strong>, a hepatobiliary and pancreatic surgical oncologist and clinician-scientist at&nbsp;Princess Margaret Cancer Centre, University Health Network and&nbsp;a professor of&nbsp;surgery&nbsp;and&nbsp;laboratory medicine and pathobiology&nbsp;in Temerty Medicine. He is also director of the PanCuRx Translational Research Initiative at the Ontario Institute for Cancer Research.</p> <p>The study was supported by the Cancer Research Society and the Canadian Institutes of Health Research.</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Tue, 22 Oct 2024 14:02:57 +0000 Christopher.Sorensen 310033 at New study identifies two critical genes in pancreatic tumours /news/new-study-identifies-two-critical-genes-pancreatic-tumours <span class="field field--name-title field--type-string field--label-hidden">New study identifies two critical genes in pancreatic tumours</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-07/10736_LTRI_Directors_20240531-167-crop.jpg?h=81d682ee&amp;itok=gOmyhOSn 370w, /sites/default/files/styles/news_banner_740/public/2024-07/10736_LTRI_Directors_20240531-167-crop.jpg?h=81d682ee&amp;itok=EDGdlYEQ 740w, /sites/default/files/styles/news_banner_1110/public/2024-07/10736_LTRI_Directors_20240531-167-crop.jpg?h=81d682ee&amp;itok=eLNdkM8G 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-07/10736_LTRI_Directors_20240531-167-crop.jpg?h=81d682ee&amp;itok=gOmyhOSn" alt="Daniel Schramek examines a petri dish"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>rahul.kalvapalle</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-07-25T10:46:33-04:00" title="Thursday, July 25, 2024 - 10:46" class="datetime">Thu, 07/25/2024 - 10:46</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>A team led by Daniel Schramek, a researcher at the Lunenfeld-Tanenbaum Research Institute (LTRI), Sinai Health and U of T's Temerty Faculty of Medicine, identified two genes that are associated with fast-growing tumours in the pancreas (photo courtesy of Mount Sinai)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/jovana-drinjakovic" hreflang="en">Jovana Drinjakovic</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/sinai-health" hreflang="en">Sinai Health</a></div> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/lunenfeld-tanenbaum-research-institute" hreflang="en">Lunenfeld-Tanenbaum Research Institute</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/molecular-genetics" hreflang="en">Molecular Genetics</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">The findings mark a significant step forward in research on pancreatic cancer, a disease that has seen little progress in treatment options</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Ƶ researchers have identified two genes that play a critical role in tumour growth in the pancreas – findings that have significant implications for understanding and treating pancreatic cancer.</p> <p>The tumour suppressor genes USP15 and SCAF1 were discovered by a research team led by <strong>Daniel Schramek</strong>, a senior investigator at the Lunenfeld-Tanenbaum Research Institute (LTRI) and deputy director of discovery research and Tony Pawson Chair in Cancer Research at Sinai Health.</p> <p>The team found that people who have mutations in these genes are more likely to develop fast-growing tumours – but these tumours are also more susceptible to chemotherapy. The findings, described in a study <a href="https://www.nature.com/articles/s41467-024-49450-3">published in <em>Nature Communications</em></a>, mark a significant step forward in research on pancreatic cancer, a disease that has seen little progress in treatment options.</p> <p>“While mutations in USP15 and SCAF1 make tumours more aggressive, they also sensitize tumours towards standard chemotherapy,” says Schramek, who is also an associate professor in the department of molecular genetics and Canada Research Chair in functional cancer genomics at the Temerty Faculty of Medicine.</p> <p>“And that means that you could stratify patients and they should have a better response to treatment.”</p> <p>The project was spearheaded by <strong>Sebastien Martinez</strong>, a former postdoctoral fellow at LTRI who is now a senior scientist at Centre de Recherche en Cancérologie de Lyon (CRCL) in France.</p> <p>Pancreatic cancer continues to have few treatment options with devastatingly low survival rates, under five years post-diagnosis. According to one estimate, pancreatic cancer could be the second leading cause of cancer deaths in the United States by 2040.</p> <p>Schramek's team achieved their breakthrough by leveraging advances in genomic medicine, specifically tumour DNA sequencing, to identify mutations and genome editing technologies.</p> <p>“Sequencing tumours allows you to find the genes that are affected and use that knowledge to develop treatments. But the problem is that every cancer has a plethora of mutations, and not all of them are disease-causing,” says Schramek.</p> <p>Cancers often feature common mutated genes in many patients, along with hundreds of less frequent mutations that appear in a smaller subset. While mutations in USP15 and SCAF1 were found in less than five per cent of patients, their effects on cancer remained unclear.&nbsp;</p> <p>Traditionally, tumour suppressor genes have been pinpointed by sequentially deleting genes in cancer cell lines and noting which deletions increase cell growth. However, these cell-based studies don't replicate the tumour's natural environment and interactions with the immune system, which are crucial for cancer progression. This likely explains why previous screens overlooked USP15 and SCAF1.</p> <p>A few years ago, Schramek's team developed a genome editing approach enabling them to remove hundreds of genes simultaneously from individual cells. This method helps identify genes that, when absent, trigger cancer in the natural body environment.</p> <p>Utilizing this technology, the Schramek lab targeted 125 genes recurrently mutated in patient pancreatic tumours and pinpointed USP15 and SCAF1 as crucial tumor suppressors and potentially prognostic factors for chemotherapy response.</p> <p>It just so happens that these genes are also absent in about 30 per cent of patients due to common genomic rearrangements in cancer.</p> <p>This finding indicates that as many as a third of pancreatic patients who lack these genes might benefit from chemotherapy and have better outcomes.</p> <p>“Historically, mutations in USP15 and SCAF1 would have been considered less important because they are not found in many patients,” Schramek says.&nbsp;“Our work shows that it is critical that we understand the functional consequences of these rare mutations as they can reveal new biology and therapeutic opportunities”</p> <p><strong>Anne-Claude Gingras</strong>, director of the Lunenfeld-Tanenbaum Research Institute and vice-president of research at Sinai Health, says the study “represents an important step forward in our understanding of the genes involved in pancreatic cancer.</p> <p>“It also shows how a cutting-edge technology developed at Sinai Health is enabling new discoveries with the potential to create benefits to patients.”&nbsp;</p> <p>This research was supported by funding from the Ontario Institute of Cancer Research, Wallace McCain Centre for Pancreatic Cancer, Princess Margaret Cancer Foundation, Terry Fox Research Institute, Canadian Cancer Society Research Institute, Pancreatic Cancer Canada and the Canadian Institute of Health.</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Thu, 25 Jul 2024 14:46:33 +0000 rahul.kalvapalle 308548 at Study points to improved detection of thyroid cancer /news/study-points-improved-detection-thyroid-cancer <span class="field field--name-title field--type-string field--label-hidden">Study points to improved detection of thyroid cancer</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-07/GettyImages-1249185188-crop.jpg?h=81d682ee&amp;itok=ygye_S3G 370w, /sites/default/files/styles/news_banner_740/public/2024-07/GettyImages-1249185188-crop.jpg?h=81d682ee&amp;itok=kZt5uRPo 740w, /sites/default/files/styles/news_banner_1110/public/2024-07/GettyImages-1249185188-crop.jpg?h=81d682ee&amp;itok=YdyvxGlk 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-07/GettyImages-1249185188-crop.jpg?h=81d682ee&amp;itok=ygye_S3G" alt="&quot;&quot;"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-07-04T16:22:19-04:00" title="Thursday, July 4, 2024 - 16:22" class="datetime">Thu, 07/04/2024 - 16:22</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>(photo by&nbsp;Basak Gurbuz Derman/Getty Images)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/gabrielle-giroday" hreflang="en">Gabrielle Giroday</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/sinai-health" hreflang="en">Sinai Health</a></div> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">“(This finding) enhances the preoperative diagnostic accuracy for patients in order to avoid unnecessary surgery for benign thyroid nodules”</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Researchers from Sinai Health and the Ƶ have gleaned new insights into how thyroid cancer could be more effectively treated.</p> <p>The study, which looked at thyroid tumour tissues and thyroid nodule biopsies&nbsp;from 620 patients at Mount Sinai Hospital from 2016 to 2022,&nbsp;examined whether differences in patients'&nbsp;RAS&nbsp;genomic variants were reflected in the status of their tumours. It also&nbsp;investigated the presence of the variant BRAF&nbsp;V600E and&nbsp;TERT&nbsp;promoter variants in the patient’s samples.</p> <p>Researchers ultimately concluded that differences in&nbsp;RAS&nbsp;in combination with&nbsp;BRAF&nbsp;V600E and&nbsp;TERT&nbsp;promoter variants could be used to arrive at more accurate cancer diagnoses in patients with indeterminate thyroid nodules.&nbsp;</p> <p>“The findings help promote understanding of the interpatient differences in genomic variation among patients who carry the same genetic mutation, thereby facilitating individualized treatment based on the extent of the mutation present in the patient,” says <strong>Guodong (David) Fu</strong>, a researcher at the Lunenfeld-Tanenbaum Research Institute and the Alex and Simona Shnaider Research Laboratory in Molecular Oncology at Mount Sinai Hospital.</p> <p>Fu adds that researchers developed novel&nbsp;molecular assays for the study using&nbsp;digital polymerase chain reaction, a technique that means they could sensitively quantify the genetic mutation level of the patient materials.</p> <p>The results were <a href="https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2818948?resultClick=1" target="_blank">published recently in&nbsp;JAMA Network</a>. Other researchers involved in the study included: <strong>Ronald Chazen</strong>, also&nbsp;of the Lunenfeld-Tanenbaum Research Institute and the Alex and Simona Shnaider Research Laboratory in Molecular Oncology, and <strong>Christina MacMillan</strong>, a pathologist at Sinai Health and an assistant professor in the Temerty Faculty of Medicine’s department of laboratory medicine and pathobiology, and&nbsp;<strong>Ian Witterick</strong>, surgeon-in-chief at Sinai Health and a professor in Temerty Medicine’s department of otolaryngology – head and neck surgery.&nbsp;</p> <p>The paper notes that there has been a sharp increase in papillary thyroid cancer since the 1980s, and that in 30 per cent of cases where a fine-needle aspiration biopsy of a suspected nodule takes place, there is an indeterminate diagnosis that may lead to a diagnostic surgery.&nbsp;</p> <p>Fu says research that assists with precision thyroid cancer detection is important for many reasons, including that some patients who seek treatment for thyroid tumours end up finding out their tumours are benign after diagnostic surgery. The findings could help medical practitioners differentiate low-risk tumours from high-risk ones, he says, and help avoid unneeded surgical procedures.&nbsp;</p> <p>“(This finding) enhances the preoperative diagnostic accuracy for patients, in order to avoid unnecessary surgery for benign thyroid nodules,” says Fu.</p> <p>Witterick, who is also otolaryngologist-in-chief&nbsp;at Mount Sinai Hospital, says the research is important&nbsp;because identifying differences in genomic variants between patients can enhance precision in cancer detection, especially diagnosing malignancies before surgery and distinguishing low-risk cancers from more aggressive ones.​</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Thu, 04 Jul 2024 20:22:19 +0000 Christopher.Sorensen 308382 at New cancer treatment slows aggressive neuroendocrine tumours: Study /news/new-cancer-treatment-slows-aggressive-neuroendocrine-tumours-study <span class="field field--name-title field--type-string field--label-hidden">New cancer treatment slows aggressive neuroendocrine tumours: Study</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-06/Simron-Singh_99-220424d-crop.jpg?h=81d682ee&amp;itok=19zYDIOx 370w, /sites/default/files/styles/news_banner_740/public/2024-06/Simron-Singh_99-220424d-crop.jpg?h=81d682ee&amp;itok=7X8cXPhL 740w, /sites/default/files/styles/news_banner_1110/public/2024-06/Simron-Singh_99-220424d-crop.jpg?h=81d682ee&amp;itok=GyEbGFAF 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-06/Simron-Singh_99-220424d-crop.jpg?h=81d682ee&amp;itok=19zYDIOx" alt="Simron Singh at Sunnybrook Health Sciences Centre"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>rahul.kalvapalle</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-07-02T09:45:10-04:00" title="Tuesday, July 2, 2024 - 09:45" class="datetime">Tue, 07/02/2024 - 09:45</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>Simron Singh, a medical oncologist at Sunnybrook Health Sciences Centre and associate professor in the Temerty Faculty of Medicine, led a study that found that radioligand therapy reduces the risk of advanced neuroendocrine tumour progression and death&nbsp;(photo by Kevin Van Paassen, Sunnybrook)</em></p> </div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/department-medicine" hreflang="en">Department of Medicine</a></div> <div class="field__item"><a href="/taxonomy/term/6923" hreflang="en">Sunnybrook Health Sciences Centre</a></div> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">Research led by scientists at Sunnybrook Health Sciences Centre and U of T showed radioligand therapy to be an effective first-line treatment for advanced uncurable cancers<br> </div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>A novel approach for early cancer treatment known as radioligand therapy (RLT) has been shown to significantly reduce the risk of advanced neuroendocrine tumour progression and death, according to research led by scientists at Sunnybrook Health Sciences Centre and the Ƶ.</p> <p>Results of the multi-centre clinical trial, which were <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)00701-3/abstract">published in&nbsp;<em>The Lancet</em></a>, provided evidence for the first time that RLT – when applied in the early stages after a patient’s diagnosis – slowed down the progression of aggressive grade 2 and 3 neuroendocrine tumours of the gastrointestinal tract.&nbsp;</p> <p>The treatment was shown to extend&nbsp;the average time of “progression-free survival” from approximately 8.5 months to 22.8 months.&nbsp;</p> <p>“This is the first study to show the effectiveness of RLT as the ‘first-line’ treatment with advanced uncurable cancer, or any cancer,” said the study’s global principal investigator <strong>Simron Singh</strong>, a medical oncologist at Sunnybrook and associate professor in the department of medicine at U of T’s Temerty Faculty of Medicine. “This trial is groundbreaking not only for patients with neuroendocrine cancers, but for all cancer patients as it has implications for the practice of cancer treatment broadly.”</p> <p>Singh described RLT as a “game changer” in the treatment of cancer, which has traditionally been carried out by surgery, drugs or radiation. “While it’s technically radiation, it is given via a chemotherapy route through the blood until it reaches the precise location of the tumour,” said Singh, who is also an affiliate scientist at Sunnybrook Research Institute and co-founder of the&nbsp;Susan Leslie Clinic for Neuroendocrine Tumours&nbsp;at Sunnybrook’s Odette Cancer Centre.</p> <p>RLT involves injecting radioactive isotopes – in this case, the drug Lutathera&nbsp;– through an IV. This method targets&nbsp;<span style="font-family:&quot;Open Sans&quot;,sans-serif;mso-fareast-font-family: &quot;Times New Roman&quot;;color:#485667;mso-font-kerning:0pt;mso-ligatures:none">specific cancer cell receptors, delivering precise radiation to kill cancer cells while preserving healthy tissue.&nbsp;<o:p></o:p></span></p> <p>The study evaluated the use of RLT earlier as a first-line (or “up front”) treatment for patients newly diagnosed with grade 2 or 3 advanced gastrointestinal neuroendocrine tumours. Although neuroendocrine cancer is uncommon, incidence is rising rapidly, and few treatments exist for patients. This cancer is resistant to most therapies, making it challenging to treat.</p> <p>The results confirm the clinical benefit of earlier use of RLT for patients diagnosed with aggressive and life-threatening tumours, said Singh. “This is the next step in personalized targeted cancer therapy for patients, focused on more effectively killing cancer cells, while limiting the damage to surrounding healthy tissues.”</p> <p>Further investigations of RLT as a therapeutic option are ongoing to evaluate overall survival and long-term safety, which will better define next steps for how this therapy will change cancer treatment world-wide.</p> <p>The multi-site trial included investigators and participants from Canada, the United States, France, Germany, Italy, Netherlands, South Korea, Spain and the UK. An overview of the results was presented at the&nbsp;2024&nbsp;American Society of Clinical Oncology (ASCO) Gastrointestinal (GI) Cancers Symposium&nbsp;in January 2024.</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> <div class="field field--name-field-add-new-author-reporter field--type-entity-reference field--label-above"> <div class="field__label">Add new author/reporter</div> <div class="field__items"> <div class="field__item"><a href="/news/authors-reporters/nadia-radovini" hreflang="en">Nadia Radovini</a></div> </div> </div> Tue, 02 Jul 2024 13:45:10 +0000 rahul.kalvapalle 308154 at Researchers uncover DNA repair mechanism that could yield treatments for cancer, premature aging /news/researchers-uncover-dna-repair-mechanism-could-yield-treatments-cancer-premature-aging <span class="field field--name-title field--type-string field--label-hidden">Researchers uncover DNA repair mechanism that could yield treatments for cancer, premature aging</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-05/20240318_dsbNET-paper_3I8A5165.jpg?h=782ba1fc&amp;itok=mT0O2VKy 370w, /sites/default/files/styles/news_banner_740/public/2024-05/20240318_dsbNET-paper_3I8A5165.jpg?h=782ba1fc&amp;itok=Bp1xdmfs 740w, /sites/default/files/styles/news_banner_1110/public/2024-05/20240318_dsbNET-paper_3I8A5165.jpg?h=782ba1fc&amp;itok=m4yEv56C 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-05/20240318_dsbNET-paper_3I8A5165.jpg?h=782ba1fc&amp;itok=mT0O2VKy" alt="&quot;&quot;"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-05-08T10:03:08-04:00" title="Wednesday, May 8, 2024 - 10:03" class="datetime">Wed, 05/08/2024 - 10:03</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>From left to right: researchers Mia Stanić, Razqallah Hakem, Mitra Shokrollahi, Karim Mekhail and Anisha Hundal (photo by Erin Howe)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/erin-howe" hreflang="en">Erin Howe</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/princess-margaret-cancer-centre" hreflang="en">Princess Margaret Cancer Centre</a></div> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/resarch-innovation" hreflang="en">Resarch &amp; Innovation</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/laboratory-medicine-and-pathobiology" hreflang="en">Laboratory Medicine and Pathobiology</a></div> <div class="field__item"><a href="/news/tags/university-health-network" hreflang="en">University Health Network</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">“It’s exciting to think about where these findings will lead us next”</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Researchers at the Ƶ and partner hospitals have discovered a DNA repair mechanism that advances understanding of how human cells stay healthy – a finding that could lead to new treatments for cancer and premature aging.</p> <p>The&nbsp;study, <a href="https://www.nature.com/articles/s41594-024-01286-7">published in the journal&nbsp;<em>Nature Structural and Molecular Biology</em></a>, also sheds light on the mechanism of action of some existing chemotherapy drugs.</p> <p>“We think this research solves the mystery of how DNA double-strand breaks and&nbsp;the nuclear envelope connect for repair in human cells,”&nbsp;said&nbsp;<strong>Karim Mekhail</strong>, co-principal investigator on the study and a professor of&nbsp;laboratory medicine and pathobiology&nbsp;in U of T’s Temerty Faculty of Medicine.</p> <p>“It also makes many previously published discoveries in other organisms applicable in the context of human DNA repair, which should help science move even faster.”</p> <p>DNA double-strand breaks arise when cells are exposed to radiation and chemicals, and through internal processes such as DNA replication. They are one of the most serious types of DNA damage because they can stall cell growth or put it in overdrive, promoting aging and cancer.</p> <p>The new discovery, made in human cells and in collaboration with&nbsp;<strong>Razqallah Hakem&nbsp;</strong>– a senior scientist at UHN’s Princess Margaret Cancer Centre, University Health Network, and a professor in Temerty Medicine’s department of medical biophysics and department of laboratory medicine and pathobiology&nbsp;– extends prior research on DNA damage in yeast by Mekhail and other scientists.</p> <p>In 2015, Mekhail and collaborators&nbsp;<a href="https://temertymedicine.utoronto.ca/news/scientists-discover-first-dna-ambulance">showed&nbsp;how&nbsp;motor proteins&nbsp;deep inside&nbsp;the&nbsp;nucleus of yeast cells transport double-strand breaks to “DNA hospital-like” protein complexes embedded in the nuclear envelope at the edge of the nucleus</a>.</p> <p>Other studies uncovered related mechanisms during DNA repair in flies and other organisms. However, scientists exploring similar mechanisms in human and other mammalian cells reported little to no DNA mobility for most breaks.</p> <p>“We knew that nuclear envelope proteins were important for DNA repair across most of these organisms, so we wondered how to explain the limited mobility of damaged DNA in mammalian cells,” Mekhail says.</p> <p>The answer is both surprising and elegant.</p> <p>When DNA inside the nucleus of a human cell is damaged,&nbsp;a specific network of microtubule filaments&nbsp;forms in the cytoplasm around the nucleus and pushes on the nuclear envelope. This prompts the formation of tiny tubes, or tubules, which reach into the nucleus and catch most double-strand breaks.</p> <p>“It’s like fingers pushing on a balloon,” says Mekhail. “When you squeeze a balloon, your fingers form tunnels in its structure, which forces some parts of the balloon’s exterior inside itself.”</p> <p>Further research by the study authors detailed several aspects of this process. Enzymes called DNA damage response kinases and tubulin acetyltransferase are the master regulators of the process, and promote the formation of the tubules.</p> <p>Enzymes deposit a chemical mark on a specific part of the microtubule filaments, which causes them to recruit tiny motor proteins and push on the nuclear envelope. Consequently, the repair-promoting protein complexes push the envelope deep into the nucleus, creating bridges to the DNA breaks.</p> <p>“This ensures that the nucleus undergoes a form of reversible metamorphosis, allowing the envelope to temporarily infiltrate DNA throughout the nucleus, capturing and reconnecting broken DNA,” says Mekhail.</p> <p>The findings have significant implications for some cancer treatments.</p> <p>Normal cells use the nuclear envelope tubules to repair DNA, but cancer cells appear to need them more. To explore the mechanism's potential impact, the team analyzed data representing over 8,500 patients with various cancers. The need was visible in several cancers, including triple-negative breast cancer, which is highly aggressive.&nbsp;</p> <p>“There is a huge effort to identify new therapeutic avenues for cancer patients, and this discovery is a big step forward,” says&nbsp;Hakem.</p> <p>“Until now, scientists were unclear as to the relative impact of the nuclear envelope in the repair of damaged DNA in human cells. Our collaboration revealed that targeting factors that modulate the nuclear envelope for damaged DNA repair effectively restrains breast cancer development,” Hakem says.</p> <p>In the aggressive triple-negative breast cancer, there are elevated levels of the tubules –&nbsp;likely because they have more DNA damage than normal cells. When the researchers knocked out the genes needed to control the tubules, cancer cells were less able to form tumours.</p> <p>One medication used to treat triple-negative breast cancer is a class of drugs called PARP inhibitors. PARP is an enzyme that binds to damaged DNA and helps repair it. PARP inhibitors block the enzyme from performing repair, preventing the ends of a DNA double-strand break in cancer cells from reconnecting to one another.</p> <p>The cancer cells end up joining two broken ends that are not part of the same pair. As more mismatched pairs are created, the resulting DNA structures become impossible for cells to copy and divide.</p> <p>“Our study shows that the drug’s ability to trigger these mismatches relies on the tubules. When fewer tubules are present, cancer cells are more resistant to PARP inhibitors,” says Hakem.</p> <p>Mekhail says the work underscores&nbsp;the importance of cross-disciplinary collaboration.</p> <p>“The brain power behind every project is crucial. Every team member counts. Also, every right collaborator added to the research project is akin to earning another doctorate in a new specialty –&nbsp;it’s powerful,” he says.</p> <p>Mekhail notes the discovery is also relevant to premature aging conditions like progeria. The rare genetic condition causes rapid aging within the first two decades of life, commonly leading to early death.</p> <p>Progeria is linked to a gene coding for lamin A. Mutations in this gene reduce the rigidity of the nuclear envelope. The team found that expression of mutant lamin A is sufficient to induce the tubules, which DNA damaging agents further boosted. The team thinks that even weak pressure on the nuclear envelope spurs the creation of tubules in premature aging cells.&nbsp;</p> <p>The findings suggest that in progeria, DNA repair may be compromised by the presence of too many or poorly regulated tubules. The study results also have implications for many other clinical conditions, Mekhail says.</p> <p>“It’s exciting to think about where these findings will lead us next,” says Mekhail. “We have excellent colleagues and incredible trainees here at Temerty Medicine and in our partner hospitals. We’re already working toward following this discovery and using our work to create novel therapeutics.”</p> <p>The research was supported by the Canadian Institutes of Health Research, Royal Society of Canada, U of T and Princess Margaret Hospital.</p> <h3><a href="http://lmp.utoronto.ca/news/team-effort-reveals-cells-reshape-their-nucleus-repair-dna-impacting-cancer-and-aging">Read more at the department of laboratory medicine and pathobiology</a></h3> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Wed, 08 May 2024 14:03:08 +0000 Christopher.Sorensen 307804 at Researchers pinpoint issue that could be hampering common chemotherapy drug /news/researchers-pinpoint-issue-could-be-hampering-common-chemotherapy-drug <span class="field field--name-title field--type-string field--label-hidden">Researchers pinpoint issue that could be hampering common chemotherapy drug </span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-03/GettyImages-589010636-crop.jpg?h=81d682ee&amp;itok=NKbWWbKZ 370w, /sites/default/files/styles/news_banner_740/public/2024-03/GettyImages-589010636-crop.jpg?h=81d682ee&amp;itok=RBEThzLa 740w, /sites/default/files/styles/news_banner_1110/public/2024-03/GettyImages-589010636-crop.jpg?h=81d682ee&amp;itok=gtnpaCHy 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-03/GettyImages-589010636-crop.jpg?h=81d682ee&amp;itok=NKbWWbKZ" alt="chemotherapy drug IV bags on a stand"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-03-18T11:00:03-04:00" title="Monday, March 18, 2024 - 11:00" class="datetime">Mon, 03/18/2024 - 11:00</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>(photo by Glasshouse Images/Getty Images)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/anika-hazra" hreflang="en">Anika Hazra</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/donnelly-centre-cellular-biomolecular-research" hreflang="en">Donnelly Centre for Cellular &amp; Biomolecular Research</a></div> <div class="field__item"><a href="/news/tags/biochemistry" hreflang="en">Biochemistry</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">Study finds two enzymes that work against the chemotherapy drug gemcitabine, preventing it from effectively treating pancreatic cancer</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Researchers at the Ƶ’s&nbsp;Donnelly Centre for Cellular and Biomolecular Research&nbsp;have found two enzymes that work against the chemotherapy drug gemcitabine, preventing it from effectively treating pancreatic cancer.</p> <p>The enzymes –&nbsp;APOBEC3C and APOBEC3D –&nbsp;increase during gemcitabine treatment and promote resistance to DNA replication stress in pancreatic cancer cells.</p> <p>This, in turn, counteracts the effects of gemcitabine and allows for the growth of cancer cells.</p> <figure role="group" class="caption caption-drupal-media align-left"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/2024-03/Tajinder-Ubhi-and-Grant-Brown-crop.jpg" width="350" height="233" alt="&quot;&quot;"> </div> </div> <figcaption><em>Tajinder Ubhi and Grant Brown (supplied images)</em></figcaption> </figure> <p>“Pancreatic cancer has proven to be very challenging to treat, as it is usually diagnosed at stage 3 or 4,” said&nbsp;<strong>Tajinder Ubhi</strong>, first author on the study and a former PhD student in&nbsp;biochemistry&nbsp;in U of T’s&nbsp;Temerty Faculty of Medicine.</p> <p>“It is the most lethal type of cancer in Canada, with an average survival time of less than two years. While chemotherapy with gemcitabine has increased survival by a few months in clinical trials, options for treatment of pancreatic cancer remain limited.”</p> <p>The findings were&nbsp;<a href="https://www.nature.com/articles/s43018-024-00742-z">published in the journal&nbsp;<em>Nature Cancer</em></a>.</p> <p>Replication stress is the key process by which gemcitabine stops cancer cells from continuing to multiply. It involves the dysregulation of DNA replication, which occurs when cells divide. Replication stress can transform a healthy cell into a cancerous one, but can also be activated within cancer cells to eliminate them.</p> <p>Gemcitabine has been used for nearly three decades to treat a wide variety of cancers, including pancreatic, breast and bladder cancer. However, a downside of using gemcitabine to&nbsp;target dividing cells is that it can produce toxic side effects in tissues that aren’t being targeted for treatment.</p> <p>Ubhi and other members of Professor&nbsp;<strong>Grant Brown</strong>’s lab at the Donnelly Centre have been trying to understand the possible causes of replication stress and its impacts. One way to do this is by studying the stress response mechanisms in cancer cells treated with gemcitabine.</p> <p>“We conducted a genome-wide CRISPR screen to find genes that could increase the sensitivity of pancreatic cancer cells to gemcitabine,” said Brown, professor of biochemistry at the Donnelly Centre and in the Temerty Faculty of Medicine who is the principal investigator on the study.</p> <p>“We were excited to identify APOBEC3C and APOBEC3D because other enzymes in the APOBEC3 family can cause cancers to eventually become resistant to treatment. We discovered a more direct role for the enzymes, where they actually protect pancreatic cancer cells from gemcitabine therapy.”</p> <p>Neither enzyme is naturally found in high concentrations within healthy or cancerous cells. The catch is that the replication stress the drug causes in pancreatic cancer cells in turn triggers an increase in both enzymes. The research team found that removing either APOBEC3C or APOBEC3D kills pancreatic cells by stymieing DNA repair and destabilizing the cell genome.</p> <p>“What is most exciting is that the removal of just APOBEC3C or APOBEC3D is enough to stop the replication of gemcitabine-treated pancreatic cancer cells,” said Ubhi. “This indicates that the enzymes could be effective new targets for treating this form of cancer.”</p> <p>The research received support from the Canada Foundation for Innovation, the Canadian Cancer Society, Canadian Friends of the Hebrew University, the Canadian Institutes of Health Research, Cold Spring Harbor Laboratory, the Government of Ontario, the Lustgarten Foundation, the Ministry for Culture and Innovation of Hungary, the U.S. National Institutes of Health, the Northwell Health Affiliation, the Ontario Institute for Cancer Research, Pancreatic Cancer Canada, the Princess Margaret Cancer Foundation, the Simons Foundation, the Terry Fox Research Institute and the Thompson Foundation.</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Mon, 18 Mar 2024 15:00:03 +0000 Christopher.Sorensen 306839 at U of T researchers develop rapid MRI technique for better cancer detection and therapy /news/u-t-researchers-develop-rapid-mri-technique-better-cancer-detection-and-therapy <span class="field field--name-title field--type-string field--label-hidden">U of T researchers develop rapid MRI technique for better cancer detection and therapy</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2024-02/GettyImages-1297207105-crop.jpg?h=81d682ee&amp;itok=g4NOkbzw 370w, /sites/default/files/styles/news_banner_740/public/2024-02/GettyImages-1297207105-crop.jpg?h=81d682ee&amp;itok=gkhndD6J 740w, /sites/default/files/styles/news_banner_1110/public/2024-02/GettyImages-1297207105-crop.jpg?h=81d682ee&amp;itok=H8WGHQuL 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2024-02/GettyImages-1297207105-crop.jpg?h=81d682ee&amp;itok=g4NOkbzw" alt="MRI technicians observe an MRI scan"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2024-02-23T14:30:43-05:00" title="Friday, February 23, 2024 - 14:30" class="datetime">Fri, 02/23/2024 - 14:30</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>(photo by Willie B. Thomas/Getty Images)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/matthew-tierney" hreflang="en">Matthew Tierney</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/institute-biomedical-engineering" hreflang="en">Institute of Biomedical Engineering</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/electrical-computer-engineering" hreflang="en">Electrical &amp; Computer Engineering</a></div> <div class="field__item"><a href="/news/tags/faculty-applied-science-engineering" hreflang="en">Faculty of Applied Science &amp; Engineering</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">“We create images every second, and sometimes less, and those images are not going to suffer from low resolution”</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Researchers at the Ƶ’s Faculty of Applied Science &amp; Engineering have developed a rapid magnetic resonance imaging (MRI)&nbsp;technique to help doctors better detect and diagnose tumours.</p> <p>The new approach – by&nbsp;<strong>Hai-Ling Cheng</strong>, a professor in the Institute of Biomedical Engineering and the Edward S. Rogers Sr. department of electrical and computer engineering,&nbsp;and PhD candidate&nbsp;<strong>Alex Mertens</strong>&nbsp;– could provide physicians with guidance during surgery and other therapeutic interventions.</p> <p>Based on novel analysis of raw patient data collected from imaging sessions with standard MRI equipment, the algorithm Cheng and Mertens developed reduces the duration between each image acquisition from more than 20 seconds to one second without sacrificing image sharpness.</p> <p>“People in the field have been trying to get high spatial resolution concurrently with temporal resolution for the past 25 years,” says Cheng.</p> <p>Cheng and Mertens,&nbsp;with the help of the U of T <a href="https://research.utoronto.ca/partnerships/partnerships">Innovations and Partnerships Office</a>, have applied for a patent and are partnering with companies to bring their MRI technique to market.</p> <p>“In practice, doctors always follow up imaging results with a biopsy for definitive confirmation to more accurately determine the grade of cancer and its stage,” Cheng says.</p> <p>“Our technique is not meant to displace the biopsy. But by better characterizing the underlying pathology at the vascular and cellular level, we can mitigate randomness in the sampling when the doctor goes in with a biopsy needle.”</p> <figure role="group" class="caption caption-drupal-media align-center"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/styles/scale_image_750_width_/public/2024-02/Cheng-1-highres-crop_0.jpg?itok=0-TqKNtK" width="750" height="500" alt="&quot;&quot;" class="image-style-scale-image-750-width-"> </div> </div> <figcaption><em>Professor Hai-Ling Cheng, pictured, and ECE PhD candidate Alex Mertens have developed a novel method to analyze data acquired from magnetic resonance imaging (photo by Matthew Tierney)</em></figcaption> </figure> <p>MRI is used to scan soft tissues like muscle or fat because it offers the best contrast compared to other modalities such as X-rays and ultrasounds. The contrast allows doctors to discern different cell types and identify small cancerous growths.</p> <p>“Let’s say you’ve got a liver and a kidney, and you want to image them both in the same area of the body,” says Cheng. “If you were to take an X-ray, you would get one contrast level – one grey scale specific to the liver and one grey scale specific to the kidney.”</p> <p>With MRI technology, however, there’s different physics at play that allows for refined gradients. An MRI scanner produces a strongly magnetized field inside the patient’s body into which it pulses a radio frequency, or RF, wave. The wave affects the water protons in soft tissues, which react to the pulse and emit signature return signals.</p> <p>“The data from the return signal doesn’t tell you the shape of an object but the frequency content of the object,” says Cheng. “We structure that return RF signal into a matrix, which we can then convert into a high resolution image.”</p> <p>Researchers can change the magnetic strength and the frequency of the pulse to obtain different contrasts, much like a music producer can increase and decrease the volume of individual tracks in a song.</p> <p>To enhance the RF signal further, a contrast agent is intravenously injected into the patient beforehand: usually gadolinium, which is non-radioactive. The dynamics of the gadolinium distribution – that is, the speed of its uptake and washout in cells – give doctors additional information about the malignancy of the tumour.</p> <p>“Tumours not only have a larger blood volume, but because their blood vessels are very messed up and tortuous, they also tend to be very, very leaky,” says Cheng.</p> <p>However, the MRI procedure is notoriously slow. The scanner must repeatedly acquire frequency domain data at different coarse and fine-grain resolutions. Typical temporal resolution is 20 seconds and gadolinium washout in a tumour can take as little as 10 seconds.</p> <p>“Typically, it takes 256 acquisition lines to create one image,” says Cheng. “Rather than reconstructing a full image every 20 seconds or every minute – that’s kind of pointless, because you’re missing the dynamics – our algorithm extrapolates information based on successive sampling of just one acquisition line.</p> <p>“We create images every second, and sometimes less, and those images are not going to suffer from low resolution.”</p> <p>“The work that Hai-Ling and her team are doing is a testament to how electrical and computer engineering technologies can impact the health-care sector,” says Professor <strong>Deepa Kundur</strong>, chair of the electrical and computer engineering department in the Faculty of Applied Science &amp; Engineering. “Hai-Ling and Alex have spent years building on their knowledge of MRI physics and human biology, demonstrating how interdisciplinary perspectives in engineering save lives. Well done.”</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Fri, 23 Feb 2024 19:30:43 +0000 Christopher.Sorensen 306269 at Researchers discover lipid nanoparticle that delivers mRNA to muscles, avoids other tissues /news/researchers-discover-lipid-nanoparticle-delivers-mrna-muscles-avoids-other-tissues <span class="field field--name-title field--type-string field--label-hidden">Researchers discover lipid nanoparticle that delivers mRNA to muscles, avoids other tissues</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2023-12/Li-lab-2023-17-crop.jpg?h=b1099e65&amp;itok=znozY_BH 370w, /sites/default/files/styles/news_banner_740/public/2023-12/Li-lab-2023-17-crop.jpg?h=b1099e65&amp;itok=QH9iuKAr 740w, /sites/default/files/styles/news_banner_1110/public/2023-12/Li-lab-2023-17-crop.jpg?h=b1099e65&amp;itok=fgpyARLp 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2023-12/Li-lab-2023-17-crop.jpg?h=b1099e65&amp;itok=znozY_BH" alt="&quot;&quot;"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2023-12-15T15:01:28-05:00" title="Friday, December 15, 2023 - 15:01" class="datetime">Fri, 12/15/2023 - 15:01</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>“The substantial anti-tumor effects observed with iso-A11B5C1 underscore its promise as a viable candidate for cancer vaccine development,” says&nbsp;Jingan Chen,&nbsp;a PhD trainee from the&nbsp;Institute of Biomedical Engineering (photo by Steve Southon)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/kate-richards" hreflang="en">Kate Richards</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/institute-biomedical-engineering" hreflang="en">Institute of Biomedical Engineering</a></div> <div class="field__item"><a href="/news/tags/institutional-strategic-initiatives" hreflang="en">Institutional Strategic Initiatives</a></div> <div class="field__item"><a href="/news/tags/prime" hreflang="en">PRiME</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/graduate-students" hreflang="en">Graduate Students</a></div> <div class="field__item"><a href="/news/tags/leslie-dan-faculty-pharmacy" hreflang="en">Leslie Dan Faculty of Pharmacy</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> <div class="field__item"><a href="/news/tags/vaccines" hreflang="en">Vaccines</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">Study also showed the mRNA triggered potent cellular-level immune responses, suggesting it could be used to develop a melanoma cancer vaccine</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>A team of researchers based at the Ƶ’s Leslie Dan Faculty of Pharmacy have discovered an ionizable lipid nanoparticle that delivers&nbsp;mRNA to muscles while avoiding other tissues.</p> <p>The study, led by Assistant Professor&nbsp;<strong>Bowen Li </strong>and&nbsp;<a href="https://www.pnas.org/doi/10.1073/pnas.2309472120">published in <em>Proceedings of the National Academy of Sciences</em></a>, also showed that mRNA delivered using the lipid nanoparticles triggered potent cellular-level immune responses –&nbsp;a proof-of-concept that could lead to a potential melanoma cancer vaccine.</p> <p>Called iso-A11B5C1, the new lipid nanoparticle demonstrates exceptional mRNA delivery efficiency in muscle tissues while also minimizing unintended mRNA translation in organs such as the liver and spleen. Additionally, study results show that intramuscular administration of mRNA formulated with this nanoparticle caused potent cellular immune responses, even with limited expression observed in lymph nodes.</p> <p>“Our study showcases for the first time that mRNA lipid nanoparticles can still effectively stimulate a cellular immune response and produce robust anti-tumor effects, even without direct targeting or transfecting lymph nodes,” said Li.</p> <p>“This finding challenges conventional understandings and suggests that high transfection efficiency in immune cells may not be the only path to developing effective mRNA vaccines for cancer.”</p> <p>Lipid nanoparticles, also called LNPs, are crucial for delivering mRNA-based therapies including COVID-19 mRNA vaccines that were used worldwide during the recent pandemic. However, many LNP designs can inadvertently result in substantial mRNA expression in off-target tissues and organs like the liver or heart, resulting in often treatable but unwanted side effects. The drive to improve the safety of mRNA therapies that have the potential to treat a broad range of diseases means there is an urgent need for LNPs designed to minimize these off-target effects, explains Li, <a href="https://www.pharmacy.utoronto.ca/news-announcements/bowen-li-receives-2022-gairdner-early-career-investigator-award">a recent recipient of the&nbsp;Gairdner Early Career Investigator Award</a>.</p> <figure role="group" class="caption caption-drupal-media align-center"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/styles/scale_image_750_width_/public/2023-12/Li-lab-2023-11-crop.jpg?itok=a3lDHgji" width="750" height="500" alt="&quot;&quot;" class="image-style-scale-image-750-width-"> </div> </div> <figcaption><em>From left to right: researchers Jingan Chen, Bowen Li and Yue Xu (photo by Steve Southon)</em></figcaption> </figure> <p>The new research shows that, compared to the current benchmark LNP developed by the Massachusetts-based biotechnology company Moderna, iso-A11B5C1 demonstrated a high level of muscle-specific mRNA delivery efficiency. It also triggered a different kind of immune response than what is seen in vaccines used to treat infectious diseases.</p> <p>“Interestingly, iso-A11B5C1 triggered a lower humoral immune response, typically central to current antibody-focused vaccines, but still elicited a comparable cellular immune response. This finding led our team to further explore this as a potential cancer vaccine candidate in a melanoma model, where cellular immunity plays a pivotal role,” Li said.</p> <p>The interdisciplinary research team that conducted the study includes&nbsp;<strong>Jingan Chen</strong>, a PhD trainee from the&nbsp;Institute of Biomedical Engineering, and&nbsp;<strong>Yue Xu</strong>, a postdoctoral researcher in the Li lab and a research fellow associated with&nbsp;<a href="https://www.prime.utoronto.ca/">PRiME</a>, a U of T <a href="https://isi.utoronto.ca/">institutional strategic initiative</a>.</p> <p>“Although iso-A11B5C1 showed limited capacity to trigger humoral immunity, it effectively initiated cellular immune responses through intramuscular injection,” said Chen. “The substantial anti-tumor effects observed with iso-A11B5C1 underscore its promise as a viable candidate for cancer vaccine development.” &nbsp;</p> <h4>New platform allows for faster, more precise lipid design</h4> <p>The research team identified iso-A11B5C1 by using an advanced platform developed to quickly create a range of chemically diverse lipids for further testing. This platform, newly introduced as part of the study, overcomes several challenges by streamlining the process of creating ionizable lipids that have a high potential to be translated into therapies.</p> <p>By rapidly combining three different functional groups, hundreds to thousands of chemically diverse ionizable lipids can be synthesized within 12 hours.</p> <p>“Here we report a powerful strategy to synthesize ionizable liquids in a one-step chemical reaction,” said Xu. “This new platform provides new insights that could help guide lipid design and evaluation processes going forward and allows the field to tackle challenges in RNA delivery with a new level of speed, precision and insight.”</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Fri, 15 Dec 2023 20:01:28 +0000 Christopher.Sorensen 304961 at Certain cancers can activate 'enhancer' in the genome to drive tumour cell growth: Study /news/researchers-find-cancer-enhancer-genome-drives-tumor-cell-growth <span class="field field--name-title field--type-string field--label-hidden">Certain cancers can activate 'enhancer' in the genome to drive tumour cell growth: Study</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2023-10/29730791700_45ca854b6e_o-crop.jpg?h=afdc3185&amp;itok=65sTGCGh 370w, /sites/default/files/styles/news_banner_740/public/2023-10/29730791700_45ca854b6e_o-crop.jpg?h=afdc3185&amp;itok=egUDQNFo 740w, /sites/default/files/styles/news_banner_1110/public/2023-10/29730791700_45ca854b6e_o-crop.jpg?h=afdc3185&amp;itok=N5gN393K 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2023-10/29730791700_45ca854b6e_o-crop.jpg?h=afdc3185&amp;itok=65sTGCGh" alt="&quot;&quot;"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2023-10-16T10:30:36-04:00" title="Monday, October 16, 2023 - 10:30" class="datetime">Mon, 10/16/2023 - 10:30</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>(Photo by Ewa Krawczyk, National Cancer Institute \ Georgetown Lombardi Comprehensive Cancer Center, National Institutes of Health)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/neil-macpherson" hreflang="en">Neil Macpherson</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/cell-and-systems-biology" hreflang="en">Cell and Systems Biology</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/faculty-arts-science" hreflang="en">Faculty of Arts &amp; Science</a></div> <div class="field__item"><a href="/news/tags/graduate-students" hreflang="en">Graduate Students</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Researchers at the Ƶ have found that cancer cells can enhance tumour growth by hijacking enhancer DNA normally used when tissues and organs are formed.</p> <p>The mechanism, called “enhancer reprogramming,” occurs in bladder, uterine, breast and lung cancer&nbsp;– and could cause these types of tumors to grow faster in patients.</p> <figure role="group" class="caption caption-drupal-media align-left"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/2023-10/Professor-Jennifer-Mitchell-crop.jpg" width="300" height="400" alt="&quot;&quot;"> </div> </div> <figcaption><em>Jennifer Mitchell (supplied image)</em></figcaption> </figure> <p>The research was conducted in the lab of <strong>Jennifer Mitchell</strong>, a professor in the department of cell and systems biology&nbsp;in the Faculty of Arts &amp; Science, and&nbsp;<a href="https://academic.oup.com/nar/advance-article/doi/10.1093/nar/gkad734/7279038">published recently in the journal&nbsp;<em>Nucleic Acids Research</em></a>. It pinpoints the role that specific proteins play in regulating the enhancer region which may lead to improved treatments for these cancer types.</p> <p>Living cells, even cancer cells, follow instructions in the genome to turn genes on and off in different contexts, says first author&nbsp;<strong>Luis Abatti</strong>, a PhD candidate in Mitchell’s lab.</p> <p>“The genome is like a recipe book written in DNA that gives instructions on making all the parts of the body,” Abatti says.</p> <p>“In each organ, only the recipes relevant to that organ should be followed&nbsp;– whether it’s the instructions for lung, breast or some other tissue. Like flipping pages in a recipe book, the DNA containing the instructions for turning genes on in the lung is open and used in the lung, for example, but closed and ignored in other types of cells.</p> <figure role="group" class="caption caption-drupal-media align-right"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/2023-10/Dr-Luis-Abatti-crop.jpg" width="300" height="400" alt="&quot;&quot;"> </div> </div> <figcaption><em>Luis Abatti (supplied image)</em></figcaption> </figure> <p>“We know that some cancer cells are opening the wrong pages in the recipe book – ones that contain the SOX2 gene, which can cause tumours to grow uncontrollably. We wanted to find out: How does the gene become expressed in cancer cells?”</p> <p>The researchers analyzed genome data to look for enhancer DNA that could activate SOX2 in cancer cells. The enhancer they found is open in many different types of patient tumours, meaning this could be a cancer enhancer active in bladder, uterus, breast and lung tumours. Unlike many cancer-causing changes, the enhancer reprogramming mechanism does not arise out of mutation due to DNA damage&nbsp;– it is caused by part of the genome opening when it should be staying closed.</p> <p>The researchers then determined that the enhancer causes increased cancer cell growth because when they removed the enhancer in lab-grown cells, the cancer cells created fewer new tumour colonies.</p> <p>To figure out why cells have a DNA region that makes cancer worse, the team examined mice without this DNA region and found they do not form a separate passage for air and food in their throat as they develop. Thus, this potentially dangerous cancer-enhancer region is likely in the human genome to regulate airway formation as the human body forms. However, if a developing cancer cell opens this region, it will form a tumour that grows faster and is more dangerous for the patient.</p> <figure role="group" class="caption caption-drupal-media align-center"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/styles/scale_image_750_width_/public/2023-10/Picture1.jpg?itok=PD4J7VdS" width="750" height="563" alt="&quot;&quot;" class="image-style-scale-image-750-width-"> </div> </div> <figcaption><em>The researchers unravel the mechanism of how developmentally active enhancers become repurposed in a tumour (image:&nbsp;© Abatti et al, 2023, published by Oxford University Press on behalf of&nbsp;Nucleic Acids Research)</em></figcaption> </figure> <p>“We also found that two proteins known to have a role in the developing airways – FOXA1 and NFIB&nbsp;– are now regulating SOX2 in breast cancer,” says Mitchell, who is associate chair of research in the department of cell and systems biology and is cross-appointed to the&nbsp;department of laboratory medicine and pathobiology&nbsp;in the Temerty Faculty of Medicine.</p> <p>The enhancer is activated by the FOXA1 protein and suppressed by the NFIB protein. This means that drugs suppressing FOXA1 or activating NFIB may lead to improved treatments for bladder, uterine, breast and lung cancer.</p> <p>“Now that we know how the SOX2 gene is activated in certain types of cancers, we can look at why this is happening,” Mitchell says.</p> <p>“Why did the cancer cells end up on the wrong page of the genome recipe book?”</p> <p>The research received support from the Canadian Institutes of Health Research, the Canada Foundation for Innovation and the Ontario government.&nbsp;</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Mon, 16 Oct 2023 14:30:36 +0000 Christopher.Sorensen 303743 at Researchers challenge long-standing theory guiding nanoparticle treatment of tumours /news/researchers-challenge-long-standing-theory-guiding-nanoparticle-treatment-tumours <span class="field field--name-title field--type-string field--label-hidden">Researchers challenge long-standing theory guiding nanoparticle treatment of tumours</span> <div class="field field--name-field-featured-picture field--type-image field--label-hidden field__item"> <img loading="eager" srcset="/sites/default/files/styles/news_banner_370/public/2023-09/Nguyen%20and%20Chan_Composite%20of%20Headshots_0.jpg?h=afdc3185&amp;itok=YY4VzP7h 370w, /sites/default/files/styles/news_banner_740/public/2023-09/Nguyen%20and%20Chan_Composite%20of%20Headshots_0.jpg?h=afdc3185&amp;itok=dpGImCN7 740w, /sites/default/files/styles/news_banner_1110/public/2023-09/Nguyen%20and%20Chan_Composite%20of%20Headshots_0.jpg?h=afdc3185&amp;itok=DiftpjVf 1110w" sizes="(min-width:1200px) 1110px, (max-width: 1199px) 80vw, (max-width: 767px) 90vw, (max-width: 575px) 95vw" width="740" height="494" src="/sites/default/files/styles/news_banner_370/public/2023-09/Nguyen%20and%20Chan_Composite%20of%20Headshots_0.jpg?h=afdc3185&amp;itok=YY4VzP7h" alt="&quot;&quot;"> </div> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>Christopher.Sorensen</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2023-09-25T09:25:30-04:00" title="Monday, September 25, 2023 - 09:25" class="datetime">Mon, 09/25/2023 - 09:25</time> </span> <div class="clearfix text-formatted field field--name-field-cutline-long field--type-text-long field--label-above"> <div class="field__label">Cutline</div> <div class="field__item"><p><em>PhD student Matthew Nguyen and Professor Warren Chan found&nbsp;that about 45 per cent of nanoparticles that accumulate in tumours end up exiting them (supplied photos)</em></p> </div> </div> <div class="field field--name-field-author-reporters field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/authors-reporters/anika-hazra" hreflang="en">Anika Hazra</a></div> </div> <div class="field field--name-field-topic field--type-entity-reference field--label-above"> <div class="field__label">Topic</div> <div class="field__item"><a href="/news/topics/breaking-research" hreflang="en">Breaking Research</a></div> </div> <div class="field field--name-field-story-tags field--type-entity-reference field--label-hidden field__items"> <div class="field__item"><a href="/news/tags/institute-biomedical-engineering" hreflang="en">Institute of Biomedical Engineering</a></div> <div class="field__item"><a href="/news/tags/princess-margaret-cancer-centre" hreflang="en">Princess Margaret Cancer Centre</a></div> <div class="field__item"><a href="/news/tags/temerty-faculty-medicine" hreflang="en">Temerty Faculty of Medicine</a></div> <div class="field__item"><a href="/news/tags/donnelly-centre-cellular-biomolecular-research" hreflang="en">Donnelly Centre for Cellular &amp; Biomolecular Research</a></div> <div class="field__item"><a href="/news/tags/cancer" hreflang="en">Cancer</a></div> <div class="field__item"><a href="/news/tags/faculty-applied-science-engineering" hreflang="en">Faculty of Applied Science &amp; Engineering</a></div> <div class="field__item"><a href="/news/tags/research-innovation" hreflang="en">Research &amp; Innovation</a></div> <div class="field__item"><a href="/news/tags/university-health-network" hreflang="en">University Health Network</a></div> </div> <div class="field field--name-field-subheadline field--type-string-long field--label-above"> <div class="field__label">Subheadline</div> <div class="field__item">Study could explain why some cancer treatments are struggling in clinical trials</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Researchers at the Ƶ have developed a new theory to explain how nanoparticles enter and exit the tumours they are meant to treat, potentially rewriting an understanding of cancer nanomedicine that has guided research for nearly four decades.</p> <p>The Enhanced Permeability and Retention (EPR) effect, a concept largely unchallenged since the mid-1980s, posits that nanoparticles enter a tumour from the bloodstream through gaps between the endothelial cells that line its blood vessels&nbsp;– and&nbsp;then become trapped in the tumour due to dysfunctional lymphatic vessels.</p> <p>“The retention aspect of the EPR theory is contingent on the lymphatic vessel cavity being too small for nanoparticles to exit, thereby helping nanoparticles that carry cancer-fighting drugs to stay in the tumours,”&nbsp;said&nbsp;Matthew Nguyen, a PhD student in the&nbsp;Institute of Biomedical Engineering in the Faculty of Applied Science &amp; Engineering and the Donnelly Centre for Cellular and Biomolecular Research,&nbsp;</p> <p>“But we found&nbsp;around 45 per cent of nanoparticles that accumulate in tumours will end up exiting them.”</p> <p>Nguyen, who is a member of the&nbsp;lab&nbsp;of Professor <strong>Warren Chan</strong>, is the&nbsp;lead author on a new study that challenges the long-standing theory that was&nbsp;<a href="https://www.nature.com/articles/s41563-023-01630-0">recently published in the journal&nbsp;<em>Nature Materials</em></a>. The researchers’ findings help explain why treatments based on the EPR effect are failing in clinical trials, building on <a href="/news/how-many-nanoparticle-based-drugs-reach-tumours">earlier research from the Chan lab that showed&nbsp;less than one per cent of nanoparticles actually reach tumours</a>.</p> <p>&nbsp;</p> <figure role="group" class="caption caption-drupal-media align-center"> <div> <div class="field field--name-field-media-image field--type-image field--label-hidden field__item"> <img loading="lazy" src="/sites/default/files/styles/scale_image_750_width_/public/2023-09/41563_2023_1630_Fig3_HTML-crop.jpg?itok=AXYHXVYN" width="750" height="222" alt="&quot;&quot;" class="image-style-scale-image-750-width-"> </div> </div> <figcaption><em>Schematic of nanoparticle exit via the intratumoural lymphatic vessels. Nanoparticles in the tumour move towards the lymphatic vessel, cross the vessel wall and drain into the vessel lumen (Nguyen, L.N.M., Lin, Z.P., Sindhwani, S.&nbsp;et al.)</em></figcaption> </figure> <p>The researchers found that, contrary to the EPR effect, nanoparticles can leave tumours through their lymphatic vessels. The exit method for a nanoparticle depends on its size, with larger ones (50-100 nanometres wide) more likely to leave through lymphatic vessels in the tumours, and smaller ones (up to 15 nanometres wide) more likely to leave through lymphatic vessels surrounding the tumours.</p> <p>In rare cases, nanoparticles will exit through blood vessels.</p> <p>Nanoparticle exit from tumours occurs through spaces in the lymphatic vessel walls and transport vesicles that carry them across these walls. The researchers showed that nanoparticles will re-enter the bloodstream following lymphatic drainage, and hypothesized that these nanoparticles will eventually return to the tumour for another opportunity to treat it.</p> <p>Disproving the EPR effect was no easy feat. The Chan lab spent six years working to understand why nanoparticles do not accumulate in tumours effectively. Prior to this study, the lab focused on&nbsp;<a href="/news/most-engineered-nanoparticles-enter-tumours-through-cells-not-between-them-u-t-researchers-find">how nanoparticles enter tumours in the first place</a>. Through this and other studies, the lab developed a competing theory to the EPR effect, called the Active Transport and Retention (ATR) principle.</p> <p>Nguyen noted that the field of nanomedicine has evolved since the publication of the nanoparticle entry study in 2020. “We got more pushback from other researchers on that study compared to this one,” he said. “People have started to accept that the EPR effect is flawed.”</p> <p>With nearly half of accumulated nanoparticles exiting tumours, mostly through lymphatic vessels, future research could address this issue through nanoparticle treatments that prevent lymphatic drainage.</p> <p>“We are excited to have a better understanding of the nanoparticle tumour delivery process,” said Chan. “The results of these fundamental studies on nanoparticle entry and exit will be important for engineering nanoparticles to treat cancer.”</p> <p>The study’s findings, if applied across the field of cancer nanomedicine, promise a new direction to improve our understanding of how nanoparticles can be used to treat tumours.</p> <p>“Trying to translate cancer nanomedicine to the clinic is like a working with a black box – some drugs work, some don’t, and it’s difficult to know why,” said&nbsp;<strong>Gang Zheng</strong>, associate research director at the&nbsp;Princess Margaret Cancer Centre and a professor of&nbsp;medical biophysics&nbsp;in U of T’s Temerty Faculty of Medicine&nbsp;who was not involved in the study.</p> <p>“Chan’s dedication to better understanding the mechanisms of nanoparticle uptake and exit is shining light on these processes to help make our translation efforts more efficient and successful.”&nbsp;</p> <p>The research was supported by the Canadian Cancer Society, the Canadian Institutes of Health Research, NanoMedicines Innovation Network and the Canada Research Chairs program.</p> </div> <div class="field field--name-field-news-home-page-banner field--type-boolean field--label-above"> <div class="field__label">News home page banner</div> <div class="field__item">Off</div> </div> Mon, 25 Sep 2023 13:25:30 +0000 Christopher.Sorensen 303235 at