Navigation Links
Study reveals a reprogrammed role for the androgen receptor
Date:7/27/2009

BOSTONThe androgen receptor a protein ignition switch for prostate cancer cell growth and division is a master of adaptability. When drug therapy deprives the receptor of androgen hormones, thereby halting cell proliferation, the receptor manages to find an alternate growth route. A new study by Dana-Farber Cancer Institute and Ohio State University scientists demonstrates how.

The shift from androgen-dependent to androgen-independent cell growth occurs, in part, because the androgen receptor switches on an entirely different set of genes in the latter group than in the former, the researchers report in the July 24 issue of Cell. In contrast to androgen-dependent prostate tumors, androgen-independent ones experience an uptick in the activity of genes that control cell division, or mitosis. One such gene, called UBE2C, which causes cells to ignore a natural pause in the division process, becomes especially active, the researchers report. This pause, or "checkpoint," ensures that cell division progresses normally; without it, daughter cells may grow even more aggressively and be harder to stop.

"The evolution of prostate cancer from an androgen-dependent state to an androgen-independent one is a key step in its progression," says study senior author Myles Brown, MD, of Dana-Farber. "The discovery that the androgen receptor directs a distinct gene pathway in androgen-independent prostate cancers may lead to the identification of genes in that pathway that can be targeted by future therapies." Prostate cancers whose growth is fed by androgen are commonly treated with androgen-blocking drugs. Such medications can hold the disease in check for a period of time that varies from patient to patient, but the tumor almost invariably gains the ability to grow without external androgen.

One of the ways such cells re-start their growth is by producing their own androgen, scientists have discovered. Another way involves the androgen receptor itself the "keyhole" in the cell nucleus that androgen molecules fit into but the actual mechanism by which it operates hasn't been known.

To find that mechanism, Brown's team, including co-lead authors Qianben Wang, PhD, now of Ohio State, and Wei Li, PhD, now of Baylor College of Medicine, charted the activity levels, or expression, of genes controlled by the androgen receptor in androgen-dependent and androgen-independent prostate cancer cells. In the androgen-independent cells, they found a group of genes with epigenetic markings tiny attachments to DNA that switchs genes on and off that caused them to be especially active. The genes form a completely separate pathway from the one active in androgen-dependent cells.

It's not known what causes those epigenetic changes to occur, but "we are profiling the genome-wide epigenetic landscape of androgen-dependent and -independent cancers, trying both experimental and computational methods to identify additional regulators," says study co-senior author X. Shirley Liu, PhD, of Dana-Farber.

"The androgen receptor clearly works by an entirely different program in androgen-dependent and -independent cancers," says Wang. "Having discovered that program, we'll be in a better position to understand how it operates and how gene-targeted therapies may shut it down."


'/>"/>

Contact: Anne Doerr
anne_doerr@dfci.harvard.edu
617-632-5665
Dana-Farber Cancer Institute
Source:Eurekalert

Related biology news :

1. Childhood obesity indicates greater risk of school absenteeism, Penn study reveals
2. A study by the MUHC and McGill University opens a new door to understanding cancer
3. Study begins to reveal clues to the cause and progression of sepsis
4. Clones on task serve greater good, evolutionary study shows
5. New study warns limited carbon market puts 20 percent of tropical forest at risk
6. New study examines how rearing environment can alter navigation
7. Study links cat disease to flame retardants in furniture and to pet food
8. New continent and species discovered in Atlantic study
9. Study shows link between alcohol consumption and hiv disease progression
10. Feeling hot, hot, hot: New study suggests ways to control fever-induced seizures
11. Study finds environmental tests help predict hospital-acquired Legionnaires disease risk
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:3/11/2016)... India , March 11, 2016 ... a new market research report "Image Recognition Market by ... Application (Marketing and Advertising), by Deployment Type (On-Premises and ... Forecast To 2022", published by MarketsandMarkets, the global market ... 2015 to USD 29.98 Billion by 2020, at a ...
(Date:3/9/2016)... March 9, 2016 This BCC Research report ... of the RNA Sequencing (RNA Seq) market for the ... instruments, tools and reagents, data analysis, and services. ... of the RNA-Sequencing market such as RNA-Sequencing tools and ... main factors affecting each segment and forecast their market ...
(Date:3/8/2016)... , March 8, 2016   Valencell , ... today announced it has secured $11M in Series ... Tech, a new venture fund being launched by ... participation from existing investors TDF Ventures and WSJ ... to continue its triple-digit growth and accelerate its ...
Breaking Biology News(10 mins):
(Date:5/19/2016)... 19, 2016  AdvancedFlow Systems Inc. (AFS), a ... out of Maple Ridge, British Columbia ... its existing portfolio of contract manufacturing clients by ... with its sister companies Surround Technologies (STI) and ... industrial group that specializes in providing contract manufacturing ...
(Date:5/19/2016)... 19, 2016 - I dati ... durante il 52 ° Congresso ... - Le conclusioni dello studio indicano un ... trattati, di cui il 90% presenta una d urata ... più. Il settantadue per cento dei pazienti ha riscontrato un ...
(Date:5/18/2016)... ... , ... STACS DNA Inc., the sample tracking software company, today announced that ... processing to help them save time and reduce errors. , Sexual Assault kits are ... and victims informed of results. Due to a previous lack of tools, many forensic ...
(Date:5/17/2016)... 2016 Haselmeier announces the launch ... approval by EMA, the European Medicines Agency. Originally launched ... company, the new pen version includes enhancements to further ... confidence to patients during use. Its enhanced ... to handle with a larger display window that improves ...
Breaking Biology Technology: