Researchers at Beth Israel Deaconess Medical Center in Boston are conducting prostate cancer research on mice in mini ‘mouse hospitals’ to pinpoint the genetic causes of castration resistance (when tumors become resistant to hormone therapy and resume growth). The mice are genetically altered with a few of the genetic mutations known to cause prostate cancer in humans. They’re then diagnosed and treated with the same tools and drugs used to treat human patients, and eventually develop castration-resistant prostate cancer (CRPC) in the same way humans do. The mice are then treated with experimental drugs in order to study their effects on CRPC. A clinical trial involving men with this advanced form of prostate cancer will investigate the drug Zytiga (abiraterone), in combination with an experimental drug that effectively treated castration resistance in the mice.
A phase II clinical trial is being held to investigate the effect of an experimental drug, ABT-888, on castration-resistant prostate cancer (CRPC) in patients who have a genetic mutation known as a TMPRSS2:ERG gene fusion. In lab studies, ABT-888 used in combination with the prostate cancer drug abiraterone (Zytiga), helped shrink prostate cancer tumors and was especially effective for shrinking tumors that had the genetic mutation. The clinical trial is being led by investigators at the University of Michigan Comprehensive Cancer Center and conducted at multiple sites throughout the country. For more information about this trial, “A Randomized Gene Fusion-Stratified Phase II Trial of Abiraterone with or without ABT-888 for Patients with Metastatic Castration-Resistant Prostate Cancer,” call the U-M Cancer Answerline at 800-865-1125.
Researchers from the University of Pennsylvania and Sheba Medical Center in Israel conducted a large multi-center study involving close to 300 patients with BRCA1 and BRCA2 mutations and advanced cancer. The study looked at the effect of treating various types of cancer, including prostate and pancreatic cancer, with a drug called olaparib, a PARP inhibitor. This is the largest study to date that has evaluated the effect of this type of treatment on diseases other than breast and ovarian cancer. The researchers say that targeting BRCA1 and BRCA2 mutations is an important advancement in tailoring personalized treatments for any type of cancer.
In an article published in the Journal of Clinical Oncology, scientists discuss the tools being developed to improve the accuracy of prostate cancer screening and to distinguish high-risk from low-risk prostate cancer types. They also review potential biomarkers that may lead to personalized or targeted treatments for prostate cancer. The authors feel clinical trials should be designed to foster the development of biomarkers and to improve understanding of the development of drug resistance.
Researchers have enhanced an innovative device, the NanoVelcro Chip, which captures circulating tumor cells (CTCs), or cancer cells that have broken off of a tumor and traveled to the bloodstream. The technology allows scientists to identify and ‘grab’ cancer cells from the blood and to then analyze them for genetic changes that may lead to more personalized treatment plans. By tracking genetic changes in cancer cells, the device may also offer a better understanding of the processes leading to drug resistance.
Researchers have identified six genes that may help determine whether men with castration-resistant prostate cancer (CRPC) are low risk or high risk. Testing for the activity of these six genes may help direct personalized treatment regimens. Additional studies are being held to determine if the results of such a test would remain stable over the course of disease and whether it may be useful in other types of cancers.