Featured Research

from universities, journals, and other organizations

MicroRNA cooperation mutes breast cancer oncogenes

Date:
May 7, 2013
Source:
University of Colorado Denver
Summary:
A new study shows that turning up a few microRNAs a little may offer as much anti-breast-cancer activity as turning up one microRNA a lot – and without the unwanted side effects.

A University of Colorado Cancer Center study recently published in the journal Cell Death & Disease shows that turning up a few microRNAs a little may offer as much anti-breast-cancer activity as turning up one microRNA a lot -- and without the unwanted side effects.

It's a bit like the classic thought experiment known as the "tumor problem" formulated by Karl Dunker in 1945 and used frequently in the problem-solving literature: Imagine a person suffers from a malignant tumor in the center of her body. Radiation strong enough to kill the tumor kills any healthy tissue through which it passes. Without operating or killing healthy tissue, how can a doctor use radiation to kill the tumor?

The answer is to target the tumor from many angles -- many weak rays of radiation pass harmlessly through healthy tissue, but their combined power at the point of the tumor is enough to kill it.

In the present study, CU Cancer Center investigators used "weak" induction of multiple microRNAs that combined from many angles to regulate the known breast cancer oncogenes erbB2/erbB3 (the "tumor") without regulating non-target genes (the "healthy tissue").

"Imagine you have a microRNA that regulates genes A and B. Then you have another microRNA that regulates genes B and C. You amplify each microRNA to a degree that doesn't effect gene A or C, but their combined effect regulates gene B," says Bolin Liu, MD, assistant professor in the Department of Pathology at the University of Colorado School of Medicine.

microRNA is an attractive target in cancer therapy -- more microRNA can lead to less gene expression, turning down or off the oncogenes that cause cancer. However, to get the desired effect on gene expression frequently requires enhancing microRNA expression 100- or 1,000-fold (or more). And the induced microRNA likely has other genetic targets -- it will turn down other genes as well as the oncogene, sometimes with unfortunate consequences.

"The current study showed that two microRNAs enhanced only 3-to-6 times their natural expression could cooperate to regulate an oncogene that had previously only been affected by a microRNA enhanced by many, many times this amount," Liu says.

Specifically, the group's work shows that no one alone, but any two of the three microRNAs that regulate erbB2/erbB3 expression can affect the levels of proteins produced by the genes. These are miR-125a, miR-15b, and miR-205, which act in concert to regulate the expression of erbB2/erbB3, which are cancer-causing products of the oncogenes.

But in general, the group's novel technique could have implications far past erbB2/erbB3, allowing researchers and eventually doctors to mute the genes they want to mute without also dampening the expression of genes regulated by only one or only the other microRNA partner.


Story Source:

The above story is based on materials provided by University of Colorado Denver. The original article was written by Garth Sundem. Note: Materials may be edited for content and length.


Journal Reference:

  1. S Wang, J Huang, H Lyu, C-K Lee, J Tan, J Wang, B Liu. Functional cooperation of miR-125a, miR-125b, and miR-205 in entinostat-induced downregulation of erbB2/erbB3 and apoptosis in breast cancer cells. Cell Death and Disease, 2013; 4 (3): e556 DOI: 10.1038/cddis.2013.79

Cite This Page:

University of Colorado Denver. "MicroRNA cooperation mutes breast cancer oncogenes." ScienceDaily. ScienceDaily, 7 May 2013. <www.sciencedaily.com/releases/2013/05/130507134649.htm>.
University of Colorado Denver. (2013, May 7). MicroRNA cooperation mutes breast cancer oncogenes. ScienceDaily. Retrieved September 21, 2014 from www.sciencedaily.com/releases/2013/05/130507134649.htm
University of Colorado Denver. "MicroRNA cooperation mutes breast cancer oncogenes." ScienceDaily. www.sciencedaily.com/releases/2013/05/130507134649.htm (accessed September 21, 2014).

Share This



More Health & Medicine News

Sunday, September 21, 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:
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