Featured Research

from universities, journals, and other organizations

HDAC inhibitor may overcome resistance to common breast cancer drug

Date:
November 13, 2011
Source:
American Association for Cancer Research
Summary:
Researchers have shown how estrogen receptor-positive breast cancer tumors become resistant to tamoxifen, the only approved hormonal therapy for premenopausal patients with this type of breast cancer. They also found that introducing a novel histone deacetylase inhibitor in hormone therapy treatment can overcome resistance to hormonal therapy.

Researchers have shown how estrogen receptor-positive breast cancer tumors become resistant to tamoxifen, the only approved hormonal therapy for premenopausal patients with this type of breast cancer. They also found that introducing a novel histone deacetylase inhibitor in hormone therapy treatment can overcome resistance to hormonal therapy.

"We always thought that resistance was primarily an inborn or genetic effect," said Pamela N. Munster, M.D., director of the Early-Phase Clinical Trials Program at the University of California, San Francisco. "But this is not the case. Tumors have found a way to modify their genes to become resistant. This process is called 'epigenetics,' where genes are turned on and off, but the sequence of DNA is not altered. We have also found that with this kind of breast cancer, we can prevent that resistance with histone deacetylase (HDAC) inhibitors."

Munster presented the findings at the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics, held Nov. 12-16, 2011.

She and her colleagues found that estrogen receptor (ER)-positive breast cancer tumors alter their genes to create more AKT, a protein that spurs actions within the cell to keep it alive -- the opposite of what tamoxifen is designed to do.

In a preclinical study, researchers introduced the HDAC inhibitor PCI-24781 at an early phase of tamoxifen treatment and found that it reverses the tumor's survival strategy of increasing production of AKT, thus stopping the tumor cells from developing resistance and leading to higher levels of cell death.

"The HDACs regulate the response of AKT to tamoxifen, and together, the effects of HDAC inhibitors and tamoxifen lead to more cell death if introduced with hormonal therapy," said Munster.

She added that previous attempts to reverse hormone resistance were made later in the course of hormonal therapy treatment, "and we think that introducing these approaches earlier may be more successful," she said.

The next step is to take this drug into clinical trials to investigate whether resistance to therapy can be prevented in patients with ER-positive breast cancer. A new look at AKT as a biomarker may help identify patients who are likely to benefit from this type of treatment.

This study was funded by the National Cancer Institute.


Story Source:

The above story is based on materials provided by American Association for Cancer Research. Note: Materials may be edited for content and length.


Cite This Page:

American Association for Cancer Research. "HDAC inhibitor may overcome resistance to common breast cancer drug." ScienceDaily. ScienceDaily, 13 November 2011. <www.sciencedaily.com/releases/2011/11/111113141308.htm>.
American Association for Cancer Research. (2011, November 13). HDAC inhibitor may overcome resistance to common breast cancer drug. ScienceDaily. Retrieved September 20, 2014 from www.sciencedaily.com/releases/2011/11/111113141308.htm
American Association for Cancer Research. "HDAC inhibitor may overcome resistance to common breast cancer drug." ScienceDaily. www.sciencedaily.com/releases/2011/11/111113141308.htm (accessed September 20, 2014).

Share This



More Health & Medicine News

Saturday, September 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Sierra Leone's Nationwide Ebola Curfew Underway

Sierra Leone's Nationwide Ebola Curfew Underway

Newsy (Sep. 20, 2014) Sierra Leone is locked down as aid workers and volunteers look for new cases of Ebola. Video provided by Newsy
Powered by NewsLook.com
Changes Found In Brain After One Dose Of Antidepressants

Changes Found In Brain After One Dose Of Antidepressants

Newsy (Sep. 19, 2014) A study suggest antidepressants can kick in much sooner than previously thought. Video provided by Newsy
Powered by NewsLook.com
Could Grief Affect The Immune Systems Of Senior Citizens?

Could Grief Affect The Immune Systems Of Senior Citizens?

Newsy (Sep. 19, 2014) The study found elderly people are much more likely to become susceptible to infection than younger adults going though a similar situation. Video provided by Newsy
Powered by NewsLook.com
Jury Delivers Verdict in Salmonella Trial

Jury Delivers Verdict in Salmonella Trial

AP (Sep. 19, 2014) A federal jury has convicted three people in connection with an outbreak of salmonella poisoning five years ago that sickened hundreds of people and was linked to a number of deaths. (Sept. 19) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

More Coverage


Tamoxifen Resistance -- And How to Defeat It

Nov. 13, 2011 In the last three decades, thousands of women with breast cancer have taken the drug tamoxifen, only to discover that the therapy doesn't work, either because their tumors do not respond to the ... read more
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins