{"101681":{"#nid":"101681","#data":{"type":"news","title":"Attacking cancer cells with hydrogel nanoparticles","body":[{"value":"\u003Cp\u003EBy David Terraso\n\u003C\/p\u003E\n\u003Cp\u003EOne of the difficulties of fighting cancer is that drugs often hit other non-cancerous cells, causing patients to get sick. But what if researchers could sneak cancer-fighting particles into just the cancer cells? Researchers at the Georgia Institute of Technology and the Ovarian Cancer Institute are working on doing just that. In the online journal \u003Cem\u003EBMC Cancer\u003C\/em\u003E they detail a method that uses hydrogels - less than 100 nanometers in size - to sneak a particular type of small interfering RNA(siRNA) into cancer cells. Once in the cell the siRNA turns on the programmed cell death the body uses to kill mutated cells and help traditional chemotherapy do its job.\n\u003C\/p\u003E\n\u003Cp\u003EMany cancers are characterized by an over abundance of epidermal growth factor receptors (EGFR). When the EGFR level in a cell is elevated it tells the cell to replicate at a rapid rate. It also turns down apoptosis, or programmed cell death.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022With our technique we\u0027re inhibiting EGFR\u0027s growth, with small interfering RNA. And by inhibiting it\u0027s growth, we\u0027re increasing the cells\u0027s apoptotic function. If we hit the cell with chemotherapy at the same time, we should be able to kill the cancer cells more effectively,\u0022 said John McDonald, professor at the School of Biology at Georgia Tech and chief research scientist at the Ovarian Cancer Institute.\n\u003C\/p\u003E\n\u003Cp\u003ESmall interfering RNA is good at shutting down EGFR production, but once inside the cell siRNA has a limited life span. Keeping it protected inside the hydrogel nanoparticles allows them to get into the cancer cell safely and acts as a protective barrier around them. The hydrogel releases only a small amount of siRNA at a time, ensuring that while some are out in the cancer cell doing their job, reinforcements are held safely inside the nanoparticle until it\u00e2\u0080\u0099s time to do their job.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022It\u00e2\u0080\u0099s like a Trojan horse,\u0022 said L. Andrew Lyon, professor in the School of Chemistry and Biochemistry at Georgia Tech. \u0022We\u00e2\u0080\u0099ve decorated the surface of these hydrogels with a ligand that tricks the cancer cell into taking it up. Once inside, the particles have a slow release profile that leaks out the siRNA over a timescale of days, allowing it to have a therapeutic effect.\u0022\n\u003C\/p\u003E\n\u003Cp\u003ECells use the messenger RNA (mRNA) to generate proteins, which help to keep the cell growing. Once the siRNA enters the cell, it binds to the mRNA and recruits proteins that attack the siRNA-mRNA complex. But the cancer cell\u0027s not finished; it keeps generating proteins, so without a continuous supply of siRNA, the cell recovers. Using the hydrogel to slowly release the siRNA allows it to keep up a sustained attack so that it can continue to interrupt the production of proteins. \n\u003C\/p\u003E\n\u003Cp\u003E\u0022We\u0027ve shown that you can get knock down out to a few days time frame, which could present a clinical window to come in and do multiple treatments in a combination chemotherapy approach,\u0022 said Lyon.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022The fact that this system is releasing the siRNA slowly, without giving the cell time to immediately recover, gives us much better efficiency at killing the cancer cells with chemotherapy,\u0022 added McDonald.\n\u003C\/p\u003E\n\u003Cp\u003EPrevious techniques have involved using antibodies to knock down the proteins.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022But oftentimes, a mutation may arise in the targeted gene such that the antibody will no longer have the effect it once did, thereby increasing the chance for recurrence,\u0022 said McDonald.\n\u003C\/p\u003E\n\u003Cp\u003EThe team used hydrogels because they\u00e2\u0080\u0099re non-toxic, have a relatively slow release rate, and can survive in the body long enough to reach their target.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022It\u0027s a well-defined architecture that you\u00e2\u0080\u0099re using the intrinsic porosity of that material to load things into, and since our particles are about 98 percent water by volume, there\u00e2\u0080\u0099s plenty of internal volume in which to load things,\u0022 said Lyon.\n\u003C\/p\u003E\n\u003Cp\u003ECurrently, the tests have been shown to work \u003Cem\u003Ein vitro\u003C\/em\u003E, but the team will be initiating tests in vivo shortly.\n\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":"","field_summary":[{"value":"One of the difficulties of fighting cancer is that drugs often hit other non-cancerous cells, causing patients to get sick.","format":"limited_html"}],"field_summary_sentence":[{"value":"Attacking cancer cells with hydrogel nanoparticles"}],"uid":"27245","created_gmt":"2010-03-15 00:00:00","changed_gmt":"2016-10-08 03:11:13","author":"Troy Hilley","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2010-03-15T00:00:00-04:00","iso_date":"2010-03-15T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"101691":{"id":"101691","type":"image","title":"Hydrogel Nanoparticles. An artistic rendering of h","body":null,"created":"1449178166","gmt_created":"2015-12-03 21:29:26","changed":"1475894720","gmt_changed":"2016-10-08 02:45:20"}},"media_ids":["101691"],"related_links":[{"url":"http:\/\/www.biology.gatech.edu\/faculty\/john-mcdonald\/","title":"John McDonald"},{"url":"http:\/\/www.biology.gatech.edu\/","title":"School of Biology"},{"url":"http:\/\/ovariancancerinstitute.org\/","title":"Ovarian Cancer Institute"}],"groups":[{"id":"1275","name":"School of Biological Sciences"}],"categories":[],"keywords":[],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003ESchool of Biology\u003C\/strong\u003E\u003Cbr \/\u003EBiology\u003Cbr \/\u003E\u003Ca href=\u0022mailto:admin@biology.gatech.edu\u0022\u003EContact School of Biology\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-3700\u003C\/strong\u003E","format":"limited_html"}],"email":["admin@biology.gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}