Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Research sheds new light on why some prostate cancers become untreatable

28.04.2003


Three new studies by researchers at UC Davis Cancer Center provide new pieces to the puzzle of why some prostate cancers become resistant to androgen suppression therapy. The studies were presented Sunday afternoon at the 2003 annual meeting of the American Urological Association.



Of the nearly 190,000 men in the United States who develop prostate cancer every year, a substantial proportion will require androgen suppression therapy to reduce levels of male hormones -- a treatment that can shrink prostate cancers or slow their growth. Hormone suppression therapy eventually fails, however, as prostate cancer cells adapt to an androgen-depleted environment, a state known as androgen independence. When this happens, few treatment options remain.

Determining how androgen independence develops, and how the process can be derailed, is a chief focus of prostate cancer research at UC Davis. "If we could prevent androgen independence from happening, it would have a dramatic impact on treatment and outcomes for prostate cancer," says Ralph deVere White, chair of urology at UC Davis School of Medicine and Medical Center and director of the UC Davis Cancer Center.


Two of the studies presented Sunday report new information about p53’s role in androgen independence. Mutations in p53 are seen in two out of three prostate cancers that have developed androgen independence. In one of the studies, deVere White and his colleagues demonstrated that four particular p53 mutations -- G245S, R248W, R273C and R273H -- facilitate androgen-independent growth in human prostate cells. The researchers were able to grow the four mutant cell lines in androgen-free conditions both in cell culture and in female laboratory mice. In addition, the researchers successfully used siRNA technology to target an siRNA molecule to the R273H mutation and down-regulate (suppress) its activity -- suggesting that siRNA technology may have therapeutic value in the treatment of hormone-independent prostate cancer.

In a second study, Clifford G. Tepper and his colleagues used microarray technology to hunt for specific genes that contribute to androgen independence. They reported Sunday that over-expression of one gene, known as Id-1, is a feature of androgen-independent tumors with p53 mutations. In order to identify Id-1, the researchers profiled more than 12,000 genes. They found 21 that are over-expressed in cells harboring G245S, R248W, R273C or R273H. Further analysis singled out one, the Id-1 gene, which produces a protein known to suppress cell aging and promote tumor aggressiveness.

In the third study, Christopher Evans and his colleagues report development of the first in vivo neuroendocrine model to study the progression of prostate cancer cells from androgen dependence to androgen independence. Using the model, the researchers demonstrated that neuroendocrine differentiation contributes to androgen-independent prostate cancer growth, proliferation and migration in an androgren-free environment.


UC Davis Cancer Center, the only National Cancer Institute-designated center between San Francisco and Portland, Ore., is a program of the UC Davis School of Medicine and Medical Center.

Public Affairs
UC Davis Health System
4900 Broadway, Suite 1200
Sacramento, CA 95820
Phone: (916) 734-9040
FAX: (916) 734-9056
E-mail: publicaffairs@ucdavis.edu


Claudia Morain | EurekAlert!
Further information:
http://news.ucdmc.ucdavis.edu

More articles from Health and Medicine:

nachricht Candidate Ebola vaccine still effective when highly diluted, macaque study finds
21.10.2019 | NIH/National Institute of Allergy and Infectious Diseases

nachricht Autism spectrum disorder risk linked to insufficient placental steroid
21.10.2019 | Children's National Hospital

All articles from Health and Medicine >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Researchers watch quantum knots untie

After first reporting the existence of quantum knots, Aalto University & Amherst College researchers now report how the knots behave

A quantum gas can be tied into knots using magnetic fields. Our researchers were the first to produce these knots as part of a collaboration between Aalto...

Im Focus: A cavity leads to a strong interaction between light and matter

Researchers have succeeded in creating an efficient quantum-mechanical light-matter interface using a microscopic cavity. Within this cavity, a single photon is emitted and absorbed up to 10 times by an artificial atom. This opens up new prospects for quantum technology, report physicists at the University of Basel and Ruhr-University Bochum in the journal Nature.

Quantum physics describes photons as light particles. Achieving an interaction between a single photon and a single atom is a huge challenge due to the tiny...

Im Focus: Solving the mystery of quantum light in thin layers

A very special kind of light is emitted by tungsten diselenide layers. The reason for this has been unclear. Now an explanation has been found at TU Wien (Vienna)

It is an exotic phenomenon that nobody was able to explain for years: when energy is supplied to a thin layer of the material tungsten diselenide, it begins to...

Im Focus: An ultrafast glimpse of the photochemistry of the atmosphere

Researchers at Ludwig-Maximilians-Universitaet (LMU) in Munich have explored the initial consequences of the interaction of light with molecules on the surface of nanoscopic aerosols.

The nanocosmos is constantly in motion. All natural processes are ultimately determined by the interplay between radiation and matter. Light strikes particles...

Im Focus: Shaping nanoparticles for improved quantum information technology

Particles that are mere nanometers in size are at the forefront of scientific research today. They come in many different shapes: rods, spheres, cubes, vesicles, S-shaped worms and even donut-like rings. What makes them worthy of scientific study is that, being so tiny, they exhibit quantum mechanical properties not possible with larger objects.

Researchers at the Center for Nanoscale Materials (CNM), a U.S. Department of Energy (DOE) Office of Science User Facility located at DOE's Argonne National...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

International Symposium on Functional Materials for Electrolysis, Fuel Cells and Metal-Air Batteries

02.10.2019 | Event News

NEXUS 2020: Relationships Between Architecture and Mathematics

02.10.2019 | Event News

Optical Technologies: International Symposium „Future Optics“ in Hannover

19.09.2019 | Event News

 
Latest News

Composite metal foam outperforms aluminum for use in aircraft wings

23.10.2019 | Materials Sciences

Researchers watch quantum knots untie

23.10.2019 | Physics and Astronomy

A technology to transform 2D planes into 3D soft and flexible structures

23.10.2019 | Medical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>