Sanford-Burnham Science Blog
The Hearst Foundations have awarded Sanford-Burnham with a grant to advance research in the...
A new study involving Sanford-Burnham's Erkki Ruoslahti, M.D., Ph.D., contributing to work by Samir...
One way to inhibit a tumor’s growth is to choke off its blood supply. The trick is to create a...
The U.S. Defense Advanced Research Projects Agency (DARPA) has awarded $6 million to a team of...
Sanford-Burnham's Erkki Ruoslahti, M.D., Ph.D., is a co-author of the study.
Conventional treatments for diseases such as cancer can carry harmful side effects—and the primary reason is that such treatments are not targeted specifically to the cells of the body where they’re needed. What if drugs for cancer, cardiovascular disease, and other diseases can be targeted specifically and only to cells that need the medicine, and leave normal tissues untouched?
These nanoparticles of porous silicon, each 100 times smaller than a human hair, contain microscopic reservoirs that can hold and protect sensitive drugs. The surface of the particles can be covered with targeting molecules. (Photo by Chia-Chen Wu, UC San Diego)
The U.S. Defense Advanced Research Projects Agency (DARPA) has awarded $6 million to a team of researchers to develop nanotechnology therapies for the treatment of traumatic brain injury and associated infections. The award brings together a multi-disciplinary team of renowned experts in laboratory research, translational investigation, and clinical medicine. The team includes Sanford-Burnham’s Erkki Ruoslahti, M.D., Ph.D., and is led by Professor Michael J. Sailor, Ph.D., from the University of California San Diego. Also on the team are Sangeeta N. Bhatia, M.D., Ph.D., of Massachusetts Institute of Technology, and Clark C. Chen, M.D., Ph.D., of UC San Diego School of Medicine.
Dr. Jamey Marth
The Hearst Foundations recently awarded Sanford-Burnham with a grant to advance research in the Institute’s Center for Nanomedicine (CNM), led by Director Jamey Marth, Ph.D.
The CNM is a partnership between Sanford-Burnham and the University of California, Santa Barbara (UCSB) that combines world-class expertise in biology, engineering, materials science, chemistry, physics, and computational modeling to address fundamental biomedical problems. The Center seeks to discover effective diagnostics and treatments, and ultimately cures, for human diseases including cancer, diabetes, and various degenerative diseases.
Erkki Ruoslahti, M.D., Ph.D., distinguished professor in both Sanford-Burnham’s NCI-designated Cancer Center in La Jolla and the Center for Nanomedicine, a Sanford-Burnham collaboration with the University of California, Santa Barbara
Glioblastoma is one of the most aggressive forms of brain cancer. Rather than presenting as a well-defined tumor, glioblastoma will often infiltrate the surrounding brain tissue, making it extremely difficult to treat surgically or with chemotherapy or radiation. Likewise, several mouse models of glioblastoma have proven completely resistant to all treatment attempts.
To overcome this hurdle, Sanford-Burnham scientists and their collaborators at the Salk Institute developed a method to combine a tumor-homing peptide, a cell-killing peptide, and a nanoparticle that both enhances tumor cell death and allows the researchers to image the tumors. When used to treat mice with glioblastoma, this new nanosystem eradicates most tumors in one model and significantly delays tumor development in another. These findings were published the week of October 3 in the Proceedings of the National Academy of Sciences of the USA.
“This is a unique nanosystem for two reasons. First, linking the cell-killing peptide to nanoparticles made it possible for us to deliver it specifically to tumors, virtually eliminating the killer peptide’s toxicity to normal tissues. Second, ordinarily researchers and clinicians are happy if they are able to deliver more drugs to a tumor than to normal tissues. We not only accomplished that, but were able to design our nanoparticles to deliver the killer peptide right where it acts—the mitochondria, the cell’s energy-generating center,” says Dr. Erkki Ruoslahti, senior author of the study and distinguished professor in both Sanford-Burnham’s NCI-designated Cancer Center in La Jolla and the Center for Nanomedicine, a Sanford-Burnham collaboration with the University of California, Santa Barbara.
Signaling nanoparticles (blue) draw in a mob of receiving nanoparticles (pink) to target tumors. (Image by Peter Allen, UCSB)
Researchers have been working for decades to develop nanoparticles that deliver cancer drugs directly to tumors, minimizing the toxic side effects of chemotherapy. However, even with the best nanoparticles, only small amounts of the treatment actually reach the tumor. Scientists at MIT, Sanford-Burnham’s Center for Nanomedicine at the University of California, Santa Barbara and the University of California, San Diego (UCSD) may have found a way to attract treatment-laden nanoparticles to tumors. Think of it as a therapeutic flash mob.
The team designed a delivery system in which nanoparticles home in on a tumor and then call in a much larger second wave of nanoparticles to dispense an anti-cancer drug. This communication between nanoparticles, enabled by the body’s own biochemistry, boosts drug delivery to tumors more than 40-fold in mouse models. The study, which was led by MIT’s Dr. Sangeeta Bhatia and received significant contributions from Sanford-Burnham’s Dr. Erkki Ruoslahti and UCSD’s Dr. Michael Sailor, was recently published online in the journal Nature Materials.
Janus particles, image courtesy of the Smith laboratory.
Nanoparticles hold great promise for improving cancer treatment. For example, they can guide drugs directly to tumors, increasing effectiveness and reducing side effects. However, significant challenges need to be overcome before these engineering marvels make it to the clinic.
On the engineering side, it’s difficult to make anything that small, around 100 nanometers (a nanometer is one billionth of a meter). Researchers also must generate particles that are uniform in size and shape and, once they’ve done their job, these particles must break down safely in the body.
On the treatment side, nanoparticles share the same obstacles as all potential treatments—cancer is wily. Because the disease evolves so rapidly, it finds ways to escape treatments, leading to drug resistance. So even the perfect nanoparticle, containing a single treatment, might not be effective in the long run.
A syndicated article that recently appeared in the Orlando Sentinel, the Los Angeles Times and other outlets described several revolutionary technologies that will change medicine in the coming decade.
In particular, the piece highlighted how new genomic technologies can personalize treatment to individual patients; how robotic surgery will help surgeons perform complex procedures on people thousands of miles away; and how new classes of diagnostic tests will allow physicians to discover diseases earlier, when they are most treatable.
The article included insights from Dr. Ranjan Perera, associate professor at Sanford-Burnham’s Lake Nona campus, and Dr. Jamey Marth, who directs the U.C. Santa Barbara–Sanford-Burnham Center for Nanomedicine. Dr. Marth is particularly excited about nanomedicine’s potential to enhance both diagnosis and treatment:
“Today’s scientists work at the molecular and atomic level with nanoparticles, to harness these biomachines that detect and bind to diseased cells. The nanoparticle then fuses with that sick cell and delivers its cargo — drugs or imaging agents.”
As 2010 comes to a close, we take a look back at our top 10 most popular posts here on Beaker, the Sanford-Burnham science blog. Enjoy… and have a Happy New Year!
(This post is our December entry in the Health Activist Blog Carnival. Read all about it here.)
Open today’s paper (or your favorite news site) and, chances are, you will read about a significant scientific breakthrough. However, you probably won’t get the back story. A team of researchers spent long days and nights in the lab. They tested many hypotheses for years — some accurate, some not. Slowly, they gathered data, submitted their findings to a journal and, after revisions, published the article.But the back story goes deeper than that. The scientists who collaborate on these discoveries have varying degrees of education and experience. In addition to the principal investigators who lead the projects, there are postdoctoral fellows and Ph.D. candidates who conduct the majority of the hands-on science.
Dr. Devanjan Sikder speaking at TEDxOrlando (Photo courtesy of the TEDxOrlando Team)
Can’t get enough TED? Neither can we. All three of Sanford-Burnham’s home cities have recently hosted TEDx conferences. In October, Dr. Jamey Marth wowed Santa Barbara with the future of nanomedicine at TEDxAmericanRiviera. Last month, Dr. Devanjan Sikder talked obesity at the inaugural TEDxOrlando and I recently had the chance to attend TEDxSanDiego.
Like most participants (we were considered participants, not just an audience), I have long admired TED talks and jumped at the chance to see one in person. TED (short for Technology, Entertainment, Design) has become so popular that local TEDx spin-offs (where x = independently organized) are springing up everywhere. The TED formula for community building brings together people who are passionate about ideas that matter and creates a forum where people with big ideas can connect.
