(Press-News.org) Chemotherapy can be very effective against small prostate tumors. Larger prostate tumors, however, accumulate cells that suppress the body's immune response, allowing the cancer to grow despite treatment. Researchers at the University of California, San Diego School of Medicine now find that blocking or removing these immune-suppressing cells allows a special type of chemotherapy -- and the immune cells it activates -- to destroy prostate tumors. This novel combination therapy, termed chemoimmunotherapy, achieved near complete remission in mouse models of advanced prostate cancer.
The study is published April 29 in Nature.
Advanced or metastatic prostate cancer does not typically respond to chemotherapy. Prostate cancers also fail to respond to a promising new type of immunotherapy drugs, called checkpoint inhibitors, which disable cancer cells' cloaking mechanism so that a person's own immune system can better fight the tumor. This specific resistance is likely due in part to immunosuppressive B cells, which are more common in larger prostate tumors in mice, as well as in advanced and metastatic prostate cancer in humans. As the name suggests, these cells keep the immune system at bay, rendering most therapies ineffective and allowing malignant tumors to grow unchecked.
In this study, researchers worked with three different mouse models of advanced prostate cancer. All three models were resistant to low doses of the chemotherapy drug oxaliplatin, which has the unique ability to activate cancer-killing immune cells. But when the researchers blocked the development or function of immunosuppressive B cells or removed them entirely before treating the mice with low-dose oxaliplatin, the prostate tumors were almost completely destroyed by the mice's own immune cells. The team got similar results when low-dose oxaliplatin was combined with a checkpoint inhibitor.
"The presence of such B cells in human prostate cancer calls for clinical testing of this novel therapeutic approach," said Shabnam Shalapour, PhD, postdoctoral researcher and first author of the study.
Prostate cancer is the second leading cause of cancer-related death in American men. About one in seven men will be diagnosed with prostate cancer during their lifetimes.
"In addition to prostate cancer, similar immunosuppressive B cells can be detected in other human cancers," said senior author Michael Karin, PhD, Distinguished Professor of Pharmacology and Pathology at UC San Diego. "This indicates that B cell-mediated immunosuppression might be the reason several other cancers are also unresponsive to checkpoint inhibitors, raising the hope that chemoimmunotherapy will have broader applications for many cancer types."
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Study co-authors include Joan Font-Burgada, Giuseppe Di Caro, Zhenyu Zhong, Elsa Sanchez-Lopez, Debanjan Dhar, Massimo Ammirante, Amy Strasner, Donna E. Hansel, Christina Jamieson, and Christopher J. Kane, UC San Diego; Gerald Willimsky, Charite-Medical University of Berlin; Tobias Klatte, Peter Birner, and Lukas Kenner, Medical University of Vienna.
This research was funded, in part, by the National Institutes of Health (grants CA127923 and AI043477), California Institute for Regenerative Medicine, German Research Foundation, Genome Research-Austria and Cancer Research Institute.
CORVALLIS, Ore. - A new study using evidence from a highly detailed ice core from West Antarctica shows a consistent link between abrupt temperature changes on Greenland and Antarctica during the last ice age, giving scientists a clearer picture of the link between climate in the northern and southern hemispheres.
Greenland climate during the last ice age was very unstable, the researchers say, characterized by a number of large, abrupt changes in mean annual temperature that each occurred within several decades. These so-called "Dansgaard-Oeschger events" took place ...
Video didn't killed the radio star, as the eponymous 1978 pop song predicted, and now, researchers have found, cross-channel discounts for online movie sales don't cannibalize online rentals of the same movie.
Analyzing data from a major movie studio that distributes its catalog of titles online, Jing Gong, a doctoral candidate in information systems and management at Carnegie Mellon University, and her co-authors measured the impact of price discounts on own- and cross-channel sales of digital movies. They confirmed their expectation that digital movie consumers are ...
Seattle, WA, April 29, 2015 - Patients with esophageal cancer who survive 5 years after undergoing surgery might breathe a sigh of relief and become complacent about continued monitoring. In fact, there is little published information on the outcome of patients with locally advanced esophageal cancer (LAEC) who survive beyond the 5-year mark. A study that will be presented by Brendon Stiles, MD, Associate Professor of Cardiothoracic Surgery, Weill Cornell Medical College, New York-Presbyterian Hospital, at the 95th AATS Annual Meeting finds that these survivors still face ...
Danish researchers from the University of Copenhagen and Herlev Hospital have made a discovery that may change the principles for treating certain types of cancer.
The discovery relates to the so-called telomeres that constitute the ends of human chromosomes. Short telomeres are related to unhealthy lifestyles, old age and the male gender - all of which are risk factors in terms of high mortality. Up until now, the assumption has been that short telomeres are related to ill health. The challenge for researchers worldwide has therefore been to find out whether or not the ...
Putnam Valley, NY. (April 28, 2015) - Mesenchymal stem cells (MSCs) have been transplanted to successfully treat a variety of diseases and conditions. The benefit of using MSCs is their ability to self-renew and differentiate into a variety of specialized cell types, such as osteoblasts (cells contributing to bone formation), chondrocytes (cartilage cells), adipocytes (fat cells), myocardiocytes (the muscle cells that make up the cardiac muscle), and neurons (nervous system cells).
MSCs have shown the ability to modulate the immune response and therefore reduce local ...
A new study by researchers at the University of California, San Diego School of Medicine has identified demographic, socioeconomic and cultural factors that contribute to a major gender disparity among U.S. men and women undergoing weight loss surgeries. Men undergo the surgeries in far lower numbers than women.
The study is published in the March issue of the Journal of Laparoendoscopic & Advanced Surgical Techniques.
Eighty percent of patients who undergo bariatric surgery, which involve procedures that either limit the amount of food that can be consumed or reduce ...
DURHAM, N.C. -- The adage "out of sight, out of mind" applies to electricity use, according to new research from Duke University's Sanford School of Public Policy.
A study of 16 years of billing records from one South Carolina utility found that residential customers using automatic bill payments consumed 4 to 6 percent more power than those who did not. Commercial electricity customers used 8 percent more. And low-income residents who enrolled in budget billing to spread the cost of seasonal peak demand across the year used 7 percent more electricity.
"It's a perverse ...
What do you do when a patient needs a blood transfusion but you don't have their blood type in the blood bank? It's a problem that scientists have been trying to solve for years but haven't been able to find an economic solution - until now.
University of British Columbia chemists and scientists in the Centre for Blood Research have created an enzyme that could potentially solve this problem. The enzyme works by snipping off the sugars, also known as antigens, found in Type A and Type B blood, making it more like Type O. Type O blood is known as the universal donor and ...
DETROIT - Nearly half of foodborne illnesses in the U.S. from 1998 through 2008 have been attributed to contaminated fresh produce. Prevention and control of bacterial contamination on fresh produce is critical to ensure food safety. The current strategy remains industrial washing of the product in water containing chlorine. However, due to sanitizer ineffectiveness there is an urgent need to identify alternative antimicrobials, particularly those of natural origin, for the produce industry.
A team of researchers at Wayne State University have been exploring natural, ...
Black and Hispanic patients will less frequently than white patients start hemodialysis with an arteriovenous fistula (connecting an artery to a vein for vascular access), a procedure for initial blood flow access known to result in superior outcomes compared with either catheters or arteriovenous grafts, according to a report published online by JAMA Surgery.
End-stage kidney disease affected more than 593,000 people in the United States in 2010 and more than 383,000 of them were treated with hemodialysis, a process that replaces the blood filtering usually done by the ...
