Featured Research

from universities, journals, and other organizations

SHIP protein identified as a B-cell tumor suppressor

Date:
October 19, 2010
Source:
Sanford-Burnham Medical Research Institute
Summary:
Researchers discover how the enzyme SHIP regulates B-cell growth in mice, findings that could impact lymphoma drugs in development.

Lymphoma is a cancer of the immune system. White blood cells divide again and again, spreading abnormally throughout the body. Lymphomas can arise from two types of white blood cells, T cells or B cells, which divide uncontrollably when the molecular mechanisms that keep them in check go awry.

Related Articles


A new study led by Robert Rickert, Ph.D., professor and director of the Inflammatory Diseases Program at Sanford-Burnham Medical Research Institute (Sanford-Burnham), explores the roles of two enzymes, called SHIP and PTEN, in B cell growth and proliferation. The results, published online on October 18 in The Journal of Experimental Medicine, show that SHIP and PTEN act cooperatively to suppress B cell lymphoma. This new information could impact several anti-lymphoma therapies currently in development.

"PTEN usually gets all the attention," Dr. Rickert explained. "But here we show for the first time that SHIP is also a major tumor suppressor in B cells."

T cells destroy infected cells, while B cells produce antibodies to neutralize foreign particles. To maintain enough of these cells to mount an immune response, but not so many that lymphomas develop, PTEN and SHIP keep a damper on PI3K, an enzyme that promotes cellular growth, survival and proliferation. PI3K signaling is altered in a number of different cancers. If PTEN is missing in T cells, the damper is removed, cells grow out of control and T cell lymphomas result. Surprisingly, this study showed that B cells deficient in either PTEN or SHIP are fine. But if mouse B cells are engineered to lack both PTEN and SHIP, lethal B cell abnormalities develop.

Could PTEN and SHIP mutations actually lead to lymphoma in humans? In an earlier collaborative study with Michael David, Ph.D., at the University of California, San Diego, Dr. Rickert and colleagues showed that inflammation -- such as occurs after infection or injury -- reduces SHIP expression. The current study suggests that while PTEN mutation in B cells alone might not cause harm, a single mutation plus inflammation could be a double whammy that gives rise to lymphoma.

"People often talk about one gene relating to one cancer," Dr. Rickert said. "But cancer is multigenic -- it takes multiple hits to subvert a cell from normal to abnormal. Here we have a model showing how that can happen in B cells."

In addition to increasing our understanding of B cell biology, this research has implications for lymphoma treatments currently in development. One such treatment targets drug-resistant B cells by depleting the body of BAFF, a compound that promotes their survival. In this new B cell lymphoma model, however, Dr. Rickert and colleagues found that B lymphoma cells still proliferate without BAFF.

On a more positive note, this study supports the development of anti-lymphoma drugs that mimic PTEN and SHIP activity by inhibiting PI3K. "Several companies are making PI3K inhibitors to treat certain kinds of lymphomas," Dr. Rickert said. "I think this system could provide a useful new preclinical model to study PI3K-dependent B cell malignancies. "

This study was funded by the National Heart, Lung and Blood Institute (NHLBI), the National Institute of Allergy and Infectious Diseases (NIAID) and the National Cancer Institute (NCI) at the National Institutes of Health (NIH).


Story Source:

The above story is based on materials provided by Sanford-Burnham Medical Research Institute. Note: Materials may be edited for content and length.


Journal Reference:

  1. A. V. Miletic, A. N. Anzelon-Mills, D. M. Mills, S. A. Omori, I. M. Pedersen, D.-M. Shin, J. V. Ravetch, S. Bolland, H. C. Morse, R. C. Rickert. Coordinate suppression of B cell lymphoma by PTEN and SHIP phosphatases. Journal of Experimental Medicine, 2010; DOI: 10.1084/jem.20091962

Cite This Page:

Sanford-Burnham Medical Research Institute. "SHIP protein identified as a B-cell tumor suppressor." ScienceDaily. ScienceDaily, 19 October 2010. <www.sciencedaily.com/releases/2010/10/101019111532.htm>.
Sanford-Burnham Medical Research Institute. (2010, October 19). SHIP protein identified as a B-cell tumor suppressor. ScienceDaily. Retrieved March 2, 2015 from www.sciencedaily.com/releases/2010/10/101019111532.htm
Sanford-Burnham Medical Research Institute. "SHIP protein identified as a B-cell tumor suppressor." ScienceDaily. www.sciencedaily.com/releases/2010/10/101019111532.htm (accessed March 2, 2015).

Share This


More From ScienceDaily



More Health & Medicine News

Monday, March 2, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Rehab Robot Helps Restore Damaged Muscles and Nerves

Rehab Robot Helps Restore Damaged Muscles and Nerves

Reuters - Innovations Video Online (Mar. 1, 2015) A rehabilitation robot prototype to help restore deteriorated nerves and muscles using electromyography and computer games. Ben Gruber reports. Video provided by Reuters
Powered by NewsLook.com
How Facebook Use Can Lead To Depression

How Facebook Use Can Lead To Depression

Newsy (Mar. 1, 2015) Margaret Duffy of the University of Missouri talks about her study on the social network and the envy and depression that Facebook use can cause. Video provided by Newsy
Powered by NewsLook.com
Could a $34 Smartphone Device Improve HIV Diagnosis in Africa?

Could a $34 Smartphone Device Improve HIV Diagnosis in Africa?

Reuters - Innovations Video Online (Feb. 27, 2015) A dongle that plugs into a Smartphone mimics a lab-based blood test for HIV and syphilis and can detect the diseases in 15 minutes, say researchers. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Doctor Says Head Transplants Possible Within Two Years

Doctor Says Head Transplants Possible Within Two Years

Buzz60 (Feb. 27, 2015) An Italian doctor is saying he could stick someone&apos;s head onto someone else&apos;s body. Patrick Jones (@Patrick_E_Jones) reports. Video provided by Buzz60
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:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

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