UC Davis researchers identify a cellular pathway that makes prostate cancer fatalNovember 28, 2007Discovery provides new treatment target for reducing cancer deaths (SACRAMENTO, Calif.) - Expanding evidence that tiny strands of RNA - called microRNAs - play big roles in the progress of some cancers, UC Davis researchers have identified one that helps jump start prostate cancer cell growth midway through the disease process, eventually causing it to become fatal. The discovery is an important link to finding new treatments targeting this cellular function and reducing cancer deaths among American men. "A number of cancer researchers are interested in microRNAs and how they are involved in diseases like leukemia," said Ralph deVere White, director of the UC Davis Cancer Center, professor of urology and senior author on the study. "But this is the first research to specifically look at the functional effects of microRNAs on the progression of prostate cancer."
Relatively new discoveries in genetic research, microRNAs are small, single strands of RNA that regulate gene expression processes between larger strands of RNA. Working with 19 samples from the cancer center's repository of prostate cancer cells, deVere White and his team used high-resolution analysis techniques to identify microRNAs that were differentially expressed. Of five that were distinct, one - miR-125b - caught their attention because of its presence at high levels in both androgen-dependent and androgen-independent prostate cancer cells. Androgens, such as testosterone, are known to promote tumor growth. While androgen suppression treatments slow the progress of prostate cancer, they do not cure it. "One of the most confounding things about prostate cancer is that after a period of success with androgen suppression therapy, the cancer starts to thrive again," deVere White explained. "That's when the disease becomes fatal. This particular microRNA supports the ability of prostate cancer cells to exist and grow in its androgen-independent state. And we currently have no effective treatments for the androgen-independent state of the disease." Now having identified a cellular link between the two phases of prostate cancer, deVere White and colleagues are hopeful that miR-125b screening will at some point become a standard diagnostic tool and that genetic and chemotherapy treatments can be developed that remove this essential survival mechanism for cancer cells. Before this can happen, the team needs to first find out if a microRNA "knockout" can be safely accomplished. "We simply don't know yet all that microRNAs do for us," said deVere White. "We will use animal models to see if we can reduce or remove one of more of them without interfering with other essential molecular functions." Another important next step is to identify the full range of microRNAs involved in prostate cancer. "There are believed to be thousands of microRNAs, and we have only identified a handful that is important to prostate cancer," said Xu-Bao Shi, a project scientist with the UC Davis Department of Urology and lead author on the study. "We must next identify if others are involved along with their regulating patterns and mechanisms in order to gain a more comprehensive picture of how they contribute to the onset and progression of the disease. Our study definitely opens up a whole new avenue in prostate cancer research." University of California - Davis - Health System Science News and Science Current Events Tag Cloud This tag cloud is a visual representation of term frequencies of random science news topics with common terms grouped together and emphasized by their display size. Life Expectancy Wildlife Conservation Oxidative Stress Quantum Dots Brain Region Snoring Statin Therapy Brain function Hypoxia Biofuels Dinosaur Bioenergy Perception Myocardial Infarction HIV transmission Tamoxifen Gene Therapy Post-traumatic Stress Disorder Decision Making Lifespan Juvenile Idiopathic Arthritis Mental Retardation Genes Progesterone Dementia
See More: Science News Tags | |||||||||||||||||||||
|
Related Prostate Cancer Current Events and Prostate Cancer News Articles Predicting the return of prostate cancer: New Johns Hopkins study betters the odds of success Cancer experts at Johns Hopkins say a study tracking 774 prostate cancer patients for a median of eight years has shown that a three-way combination of measurements has the best chance yet of predicting disease metastasis. Second gene linked to familial testicular cancer Specific variations or mutations in a particular can gene raise a man's risk of familial, or inherited, testicular germ-cell cancer, the most common form of this disease. Researchers pinpoint a new enemy for tumor-suppressor p53 Researchers at The University of Texas M. D. Anderson Cancer Center have identified a protein that marks the tumor suppressor p53 for destruction, providing a potential new avenue for restoring p53 in cancer cells. Report: Prostate cancer screening has yet to prove its worth The recent release of two large randomized trials suggests that if there is a benefit of screening, it is, at best, small. Selenium intake may worsen prostate cancer in some, study reports Higher selenium levels in the blood may worsen prostate cancer in some men who already have the disease, according to a study by researchers at Dana-Farber Cancer Institute the University of California, San Francisco. Prostate Cancer Translational Research in Europe meeting: Search for biomarkers continues Collaboration in prostate cancer translational research in Europe is not only vital to sustain the progress achieved in recent years but also to streamline current efforts between researchers and clinicians and avoid duplication or overlaps. Dr. Ronald Lewis Couples' treatment for sexual problems on the agenda for sexual medicine experts Couples' treatment for sexual problems and other innovative approaches to improving sexual health for men and women are on the agenda of sexual medicine experts. BRIT1 allows DNA repair teams access to damaged sites Like a mechanic popping the hood of a car to get at a faulty engine, a tumor-suppressing protein allows cellular repair mechanisms to pounce on damaged DNA by overcoming a barrier to DNA access. Autonomous robot detects shrapnel Bioengineers at Duke University have developed a laboratory robot that can successfully locate tiny pieces of metal within flesh and guide a needle to its exact location -- all without the need for human assistance. Green tea may affect prostate cancer progression According to results of a study published in Cancer Prevention Research, a journal of the American Association for Cancer Research, men with prostate cancer who consumed the active compounds in green tea demonstrated a significant reduction in serum markers predictive of prostate cancer progression. More Prostate Cancer Current Events and Prostate Cancer News Articles |
|||||||||||||||||||||
|
|||||||||||||||||||||
|
|||||||||||||||||||||