nanoparticles / en How many nanoparticle-based drugs reach tumours? Less than one per cent, οstudy shows /news/how-many-nanoparticle-based-drugs-reach-tumours <span class="field field--name-title field--type-string field--label-hidden">How many nanoparticle-based drugs reach tumours? Less than one per cent, οstudy shows</span> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>lavende4</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2016-04-25T15:12:32-04:00" title="Monday, April 25, 2016 - 15:12" class="datetime">Mon, 04/25/2016 - 15:12</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">Stefan Wilhelm is the lead author of a new review paper that shows less than one per cent of designer nanoparticles actually reach their intended target (photo by Neil Ta)</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/tyler-irving" hreflang="en">Tyler Irving</a></div> </div> <div class="field field--name-field-author-legacy field--type-string field--label-above"> <div class="field__label">Author legacy</div> <div class="field__item">Tyler Irving</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/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/nanoparticles" hreflang="en">nanoparticles</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/faculty-staff" hreflang="en">Faculty &amp; Staff</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">“Reality check” meta-analysis reveals that only 0.7 per cent of designer nanoparticles reach their intended target</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Targeting cancer cells for destruction while leaving healthy cells alone — that has been the promise of the emerging field of cancer nanomedicine. But a new meta-analysis from U of T’s Institute of Biomaterials &amp; Biomedical Engineering (IBBME) indicates that progress so far has been limited and new strategies are needed if the promise is to become reality.</p> <p>“The amount of research into using engineered nanoparticles to deliver cancer drugs directly to tumours has been growing steadily over the last decade, but there are very few formulations used in patients. The question is why?” says Professor&nbsp;<strong>Warren Chan</strong>&nbsp;(IBBME, ChemE, MSE), senior author on <a href="http://www.nature.com/articles/natrevmats201614">the review paper published April 26&nbsp;in <em>Nature Reviews Materials</em></a>. “We felt it was time to look at the field more closely.”</p> <p>Chan and his co-authors analysed 117 published papers that recorded the delivery efficiency of various nanoparticles to tumours — that is, the percentage of injected nanoparticles that actually reach their intended target. To their surprise, they found that the median value was about 0.7 per cent of injected nanoparticles reaching their targets, and that this number has not changed for the last ten years. “If the nanoparticles do not get delivered to the tumour, they cannot work as designed for many nanomedicines,” says Chan.</p> <p>Even more surprising was that altering nanoparticles themselves made little difference in the net delivery efficiency. “Researchers have tried different materials and nanoparticle sizes, different surface coatings, different shapes, but all these variations lead to no difference, or only small differences,” says&nbsp;<strong>Stefan Wilhelm</strong>, a post-doctoral researcher in Chan’s lab and lead author of the paper. “These results suggest that we have to think more about the biology and the mechanisms that are involved in the delivery process rather than just changing characteristics of nanoparticles themselves.”</p> <p><strong style="margin: 0px; padding: 0px; border: 0px; vertical-align: baseline; color: rgb(102, 102, 102); font-family: 'Lucida Grande', 'Lucida Sans Unicode', sans-serif; font-size: 11.0819px; line-height: 13.6418px;">[embed_content nid=7660 (class="additional class")/]</strong></p> <p>Wilhelm points out that nanoparticles do have some advantages. Unlike chemotherapy drugs which go everywhere in the body, drugs delivered by nanoparticles accumulate more in some organs and less in others. This can be beneficial: for example, one current treatment uses nanoparticles called liposomes to encapsulate the cancer drug doxorubicin.</p> <p>This encapsulation reduces the accumulation of doxorubicin in the heart, thereby reducing cardiotoxicity compared with administering the drug on its own.</p> <p>Unfortunately, the majority of injected nanoparticles, including liposomes, end up in the liver, spleen and kidneys, which is logical since the job of these organs is to clear foreign substances and poisons from the blood. This suggests that in order to prevent nanoparticles from being filtered out of the blood before they reach the target tumour, researchers may have to control the interactions of those organs with nanoparticles.</p> <p>It may be that there is an optimal particle surface chemistry, size, or shape required to access each type of organ or tissue. &nbsp;One strategy the authors are pursuing involves engineering nanoparticles that can dynamically respond to conditions in the body by altering their surfaces or other properties, much like proteins do in nature. This may help them to avoid being filtered out by organs such as the liver, but at the same time to have the optimal properties needed to enter tumors.</p> <p>More generally, the authors argue that, in order to increase nanoparticle delivery efficiency, a systematic and coordinated long-term strategy is necessary. To build a strong foundation for the field of cancer nanomedicine, researchers will need to understand a lot more about the interactions between nanoparticles and the body’s various organs than they do today. To this end, Chan’s lab has developed techniques &nbsp;to visualize these interactions across whole organs using 3D optical microscopy, a study published in ACS Nano this week.</p> <p>In addition to this, the team has set up an open online database, called the Cancer Nanomedicine Repository that will enable the collection and analysis of data on nanoparticle delivery efficiency from any study, no matter where it is published. The team has already uploaded the data gathered for the latest paper, but when the database goes live in June, researchers from all over the world will be able to add their data and conduct real-time analysis for their particular area of interest.</p> <p>“It is a big challenge to collect and find ways to summarize data from a decade of research but this article will be immensely useful to researchers in the field,” says Professor&nbsp;<strong>Julie Audet</strong>&nbsp;(IBBME), a collaborator on the study.</p> <p>Wilhelm says there is a long way to go in order to improve the clinical translation of cancer nanomedicines, but he’s optimistic about the results. “From the first publication on liposomes in 1965 to when they were first approved for use in treating cancer, it took 30 years,” he says. “In 2016, we already have a lot of data, so there’s a chance that the translation of new cancer nanomedicines for clinical use could go much faster this time. Our meta-analysis provides a ‘reality’ check of the current state of cancer nanomedicine and identifies the specific areas of research that need to be investigated to ensure that there will be a rapid clinical translation of nanomedicine developments.”&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, 25 Apr 2016 19:12:32 +0000 lavende4 13881 at Engineering nanoparticles that can change their shape to deliver cancer drugs to tumours /news/engineering-nanoparticles-can-change-their-shape-deliver-cancer-drugs-tumours <span class="field field--name-title field--type-string field--label-hidden">Engineering nanoparticles that can change their shape to deliver cancer drugs to tumours</span> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>sgupta</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2016-02-18T09:26:52-05:00" title="Thursday, February 18, 2016 - 09:26" class="datetime">Thu, 02/18/2016 - 09:26</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">“We’re making shape-changing nanoparticles,” Professor Warren Chan says. “They’re a series of building blocks, kind of like a LEGO set.” (photo by NSERC)</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/marit-mitchell" hreflang="en">Marit Mitchell</a></div> </div> <div class="field field--name-field-author-legacy field--type-string field--label-above"> <div class="field__label">Author legacy</div> <div class="field__item">Marit Mitchell</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/top-stories" hreflang="en">Top Stories</a></div> <div class="field__item"><a href="/news/tags/nanoparticles" hreflang="en">nanoparticles</a></div> <div class="field__item"><a href="/news/tags/medicine" hreflang="en">Medicine</a></div> <div class="field__item"><a href="/news/tags/ibbme" hreflang="en">IBBME</a></div> <div class="field__item"><a href="/news/tags/health" hreflang="en">Health</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/engineering" hreflang="en">Engineering</a></div> <div class="field__item"><a href="/news/tags/chemistry" hreflang="en">Chemistry</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">Attached to strands of DNA, they change shape, size and chemistry to access diseased tissue, like a key fitting into a lock</div> </div> <div class="clearfix text-formatted field field--name-body field--type-text-with-summary field--label-hidden field__item"><p>Chemotherapy isn’t supposed to make your hair fall out –&nbsp;it’s supposed to kill cancer cells. A new molecular delivery system created at οEngineering could help ensure that chemotherapy drugs get to their target while minimizing collateral damage.&nbsp;</p> <p>Many cancer drugs target fast-growing cells. Injected into a patient, they swirl around in the bloodstream acting on fast-growing cells wherever they find them. That includes tumours, but unfortunately also hair follicles, the lining of your digestive system, and your skin.</p> <p>The University of Toronto's Professor <strong>Warren Chan</strong> has spent the last decade figuring out how to deliver chemotherapy drugs into tumours –&nbsp;and nowhere else. Now his lab has designed a set of nanoparticles attached to strands of DNA that can change shape to gain access to diseased tissue. Their research will be published on Feb. 19.</p> <p>“Your body is basically a series of compartments,” says Chan. “Think of it as a giant house with rooms inside. We’re trying to figure out how to get something that’s outside, into one specific room. One has to develop a map and a system that can move through the house where each path to the final room may have different restrictions such as height and width.”</p> <p>One thing we know about cancer: no two tumours are identical. Early-stage breast cancer, for example, may react differently to a given treatment than pancreatic cancer, or even breast cancer at a more advanced stage. Which particles can get inside which tumours depends on multiple factors such as the particle’s size, shape and surface chemistry.</p> <p>Chan and his research group have studied how these factors dictate the delivery of small molecules and nanotechnologies to tumours, and have now designed a targeted molecular delivery system that uses modular nanoparticles whose shape, size and chemistry can be altered by the presence of specific DNA sequences.</p> <p>“We’re making shape-changing nanoparticles,” says Chan. “They’re a series of building blocks, kind of like a LEGO set.” The component pieces can be built into many shapes, with binding sites exposed or hidden. They are designed to respond to biological molecules by changing shape, like a key fitting into a lock.&nbsp;</p> <h2><a href="http://news.utoronto.ca/tags/warren-chan">Read more about research from Professor Chan</a></h2> <p>These shape-shifters are made of tiny&nbsp;chunks of metal with strands of DNA attached to them. Chan envisions that the nanoparticles will float around harmlessly in the blood stream, until a DNA strand binds to a sequence of DNA known to be a marker for cancer. When this happens, the particle changes shape, then carries out its function: it can target the cancer cells, expose a drug molecule to the cancerous cell, tag the cancerous cells with a signal molecule, or whatever task Chan’s team has designed the nanoparticle to carry out.</p> <p>Their work was published this week in two key studies in the <em>Proceedings of the National Academy of Sciences</em> and the leading journal S<em>cience</em>.</p> <p>“We were inspired by the ability of proteins to alter their conformation –&nbsp;they somehow figure out how to alleviate all these delivery issues inside the body,” says Chan. “Using this idea, we thought, ‘Can we engineer a nanoparticle to function like a protein, but one that can be programmed outside the body with medical capabilities?’”</p> <p>Applying nanotechnology and materials science to medicine, and particularly to targeted drug delivery, is still a relatively new concept, but one Chan sees as full of promise. The real problem is how to deliver enough of the nanoparticles directly to the cancer to produce an effective treatment.&nbsp;</p> <p>“Here’s how we look at these problems: it’s like you’re going to Vancouver from Toronto, but no one tells you how to get there, no one gives you a map, or a plane ticket, or a car –&nbsp;that’s where we are in this field,” he says. “The idea of targeting drugs to tumours is like figuring out how to go to Vancouver. It’s a simple concept, but to get there isn’t simple if not enough information is provided.”</p> <p>“We’ve only scratched the surface of how nanotechnology ‘delivery’ works in the body, so now we’re continuing to explore different details of why and how tumours and other organs allow or block certain things from getting in,” adds Chan.</p> <p>He and his group plan to apply the delivery system they’ve designed toward personalized nanomedicine –&nbsp;further tailoring their particles to deliver drugs to your precise type of tumour, and nowhere else.</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-picpath field--type-string field--label-above"> <div class="field__label">picpath</div> <div class="field__item">sites/default/files/2016-02-18-warren-chan-nserc.jpg</div> </div> Thu, 18 Feb 2016 14:26:52 +0000 sgupta 7660 at Researchers convert microbubbles into nanoparticles to fight cancer /news/researchers-convert-microbubbles-nanoparticles-fight-cancer <span class="field field--name-title field--type-string field--label-hidden">Researchers convert microbubbles into nanoparticles to fight cancer</span> <span class="field field--name-uid field--type-entity-reference field--label-hidden"><span>sgupta</span></span> <span class="field field--name-created field--type-created field--label-hidden"><time datetime="2015-03-31T07:15:45-04:00" title="Tuesday, March 31, 2015 - 07:15" class="datetime">Tue, 03/31/2015 - 07:15</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">Professor Gang Zheng</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/more-news" hreflang="en">More News</a></div> <div class="field__item"><a href="/news/tags/nanoparticles" hreflang="en">nanoparticles</a></div> <div class="field__item"><a href="/news/tags/microbubbles" hreflang="en">microbubbles</a></div> <div class="field__item"><a href="/news/tags/medicine" hreflang="en">Medicine</a></div> <div class="field__item"><a href="/news/tags/drug-delivery" hreflang="en">drug delivery</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">New discovery hold promises for more precise tumour treatment </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 University of Toronto have successfully converted microbubbles into nanoparticles that stay trapped in tumours to potentially deliver targeted, therapeutic payloads.<br> <br> The discovery, published online March 30, 2015 in&nbsp;<a href="http://www.nature.com/nnano/journal/vaop/ncurrent/full/nnano.2015.25.html" target="_blank"><em>Nature Nanotechnology</em></a>, details how Professor&nbsp;<strong>Gang Zheng</strong>&nbsp;and his research team created a new type of microbubble using a compound called porphyrin – a naturally occurring pigment in nature that harvests light.</p> <p> In the lab in pre-clinical experiments, the team used low-frequency ultrasound to burst the porphyrin containing bubbles and observed that they fragmented into nanoparticles. Most importantly, the nanoparticles stayed within the tumour and could be tracked using imaging.</p> <p> “Our work provides the first evidence that the microbubble reforms into nanoparticles after bursting and that it also retains its intrinsic imaging properties,” says Zheng, a professor of medical biophysics at U of T. “We have identified a new mechanism for the delivery of nanoparticles to tumours, potentially overcoming one of the biggest translational challenges of cancer nanotechnology. In addition, we have demonstrated that imaging can be used to validate and track the delivery mechanism."&nbsp;</p> <p> Conventional microbubbles lose all intrinsic imaging and therapeutic properties once they burst, he says, in a blink-of-an-eye process that takes only a minute or so after bubbles are infused into the bloodstream.</p> <p> “For clinicians, harnessing microbubble-to-nanoparticle conversion may be a powerful new tool that enhances drug delivery to tumours, prolongs tumour visualization and enables them to treat cancerous tumours with greater precision,” says Zheng, a senior scientist at the Princess Margaret Cancer Centre.&nbsp;</p> <p> For the past decade, Zheng’s research focus has been on finding novel ways to use heat, light and sound to advance multi-modality imaging and create unique, organic nanoparticle delivery platforms capable of transporting cancer therapeutics directly to tumours.</p> <p> The research was funded by the Canadian Institutes of Health Research (CIHR) Frederick Banting and Charles Best Canada Graduate Scholarship, the Emerging Team Grant on Regenerative Medicine and Nanomedicine&nbsp;co-funded by the CIHR and the Canadian Space Agency, the Natural Sciences and Engineering Research Council of Canada, the Ontario Institute for Cancer Research, the International Collaborative R&amp;D Project of the Ministry of Knowledge Economy, South Korea, the Joey and Toby Tanenbaum/Brazilian Ball Chair in Prostate Cancer Research, the Canada Foundation for Innovation and The Princess Margaret Cancer 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> <div class="field field--name-field-picpath field--type-string field--label-above"> <div class="field__label">picpath</div> <div class="field__item">sites/default/files/2015-03-31-precision tumour treatment-gang zheng.jpg</div> </div> Tue, 31 Mar 2015 11:15:45 +0000 sgupta 6918 at