Researchers at the Moffitt Cancer Center have found that delayed tumor growth and enhanced survival of mice bearing melanoma were possible by blocking the reconstitution of myeloid-derived suppressor cells and Tregs (suppressors of anti-tumor activity) after total body irradiation had eliminated them. Blocking myeloid-derived suppressor cells and regulatory T-cell reconstitution improved adoptive T-cell therapy, an immunotherapy designed to suppress tumor activity.
The study appears in the December issue of The Journal of Immunology.
"Melanoma is a leading cause of cancer mortality," said Shari Pilon-Thomas, Ph.D., assistant member of the Immunology Program at Moffitt. "With few nonsurgical options for treating melanoma, immunotherapy, which focuses on the induction of immunity against cancer cells, is a promising approach. However, a major hurdle in developing effective immunotherapies is tumor-induced suppression that can limit the effectiveness of tumor-specific T-cells used in immunotherapy."
Chemotherapy or radiation can induce lymphopenia, the condition of having an abnormally low level of white blood cells. This condition is optimal for adoptive T-cell therapeutic strategies. However, after the induction of lymphopenia, suppressor populations that favor tumor progression begin reconstitution, including regulatory T cells (Tregs) and myeloid derived suppressor cells (MDSC). According to the researchers, tumor-induced suppression can stem from quickly reconstituted Tregs and MDSC.
This knowledge led to their research question, whether blocking the reconstitution of suppressor populations - such as Tregs and myeloid derived suppressor cells - could lead to better immunotherapy in mice bearing melanoma. Mice were treated with docetaxel, a chemotherapeutic drug that targets MDSC, followed by adoptive T cell therapy. In brief, the study demonstrated that when myeloid-derived suppressor cells and Treg reconstitution are blocked, immunotherapy with adoptive T cell transfer is more effective.
"It was important to understand the role of these suppressor populations after the induction of lymphopenia so that we can design more effective immunotherapeutic treatments for melanoma aimed at achieving complete tumor regression," concluded Dr. Pilon-Thomas.
H. Lee Moffitt Cancer Center & Research Institute: http://www.moffitt.usf.edu
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Supply became contaminated as it passed through giant network of lead pipes that distributed water around city, scientists believe
As the cold season dribbles relentlessly onward, its worth considering who is or is not to blame for your misery
Last year a scientist said he'd found a new form of botulinum toxin, and was keeping details secret to keep the recipe from terrorists. But other science and public health labs were shut out, too.
Flu cases across the US can be accurately estimated using Wikipedia searches, and fluey tweets from Twitter users also give the game away
Workers who have a creative outlet outside the office are more likely to be creative problem solvers on the job, a study suggests. Oh, and they have more fun.
Scientists to grow a crop of camelina plants genetically modified to produce fish oils that could be used in health supplements Continue reading...
Kent Kiehl has been interviewing psychopaths for more than 20 years. More recently he's acquired a mobile MRI scanner and permission to scan the brains of New Mexico state prison inmates. He talked with WIRED about what's different in the brains of psychopaths and why he views psychopathy as a preventable mental disorder.
In Snakes, Sunrises, and Shakespeare, evolutionary psychology pioneer Gordon H. Orians traces the roots of today's human quirks in the minds of our ancestors
The World Health Organization says an outbreak of the deadly Ebola virus in West Africa has been linked to the deaths of more than 120 people. As of Monday, the organization recorded a total of 200 suspected or confirmed cases of Ebola, which is normally found in central or eastern Africa, in…
To see if low blood sugar sours even good relationships, scientists used an unusual tool: voodoo dolls representing spouses. As hunger levels rose, so did the number of pins.