MD Anderson Study Shows Why Some Brain Cancers Resist Treatment

Jo-Carolyn Goode | 3/2/2015, 5:42 p.m.
Scientists at The University of Texas MD Anderson Cancer Center may have discovered why some brain cancer patients develop resistance ...
Wei Zhang, Ph.D.

HOUSTON ― Scientists at The University of Texas MD Anderson Cancer Center may have discovered why some brain cancer patients develop resistance to standard treatments including radiation and the chemotherapy agent temozolomide.

Simply put, it’s all in their DNA, and it could open up new avenues for treating certain kinds of brain cancer.

DNA, the body’s essential storehouse for genetic information, can do marvelous things such as passing on hereditary strengths and playing a key role in virtually every bodily function. In the case of glioblastoma, the most common and aggressive type of glioma or brain cancer, it can also allow the disease to progress more quickly when it is “enhanced,” allowing damaged or mutated cancer cells to repair themselves.

“A major obstacle to effective treatment is acquired resistance to treatment,” said Wei Zhang, Ph.D., professor of Pathology. “Enhanced DNA repair can allow these cancer cells to survive, contributing to resistance and tumor recurrence. We have identified Aktr3 as having the ability to robustly stimulate glioma progression.”

Akts are proteins known as kinases that regulate cell signaling. They’re involved in many bodily processes such as cell growth, cell death and tumor growth. Akts are thought to contribute to the development and progression of many cancers including prostate, breast, liver, colorectal and others. One form of this protein, Akt3, appears to be especially prevalent in the brain.

Zhang’s findings, which are published in the March 2 issue of the Proceedings of the National Academy of Sciences, describe his team’s study results showing how Akt3 activates key DNA repair pathways.

In Zhang’s research, he reveals that Akt3 is tied to DNA’s “repair panel,” somehow boosting activation of DNA repair proteins, leading to increased DNA repair, and subsequently to cancer treatment resistance.

“This activation led to enhanced survival of brain tumor cells following radiation or treatment with temozolomide,” said Zhang. “Our work has potentially broad application to multiple cancer types in which Akt3 is expressed. Blocking this pathway may help prevent or alleviate therapeutic resistance resulting from enhanced DNA repair.”

The study was funded by the National Institutes of Health (CA141432, CA09850305 and U24CA143835), the National Cancer Institute (CA16672), the Goldhirsh Foundation, the Academy of Finland, the Sigrid Juselius Foundation, and the Finnish Funding Agency for Technology and Innovation.

MD Anderson study team members included Kristen Turner, Ph.D., Youting Sun, Ph.D., Kirsi Granberg, Limei Hu, M.D., David Cogdell, Xinhui Zhou, and Gregory Fuller, M.D., Ph.D., all from Pathology; and W.K. Alfred Yung, M.D., Neuro-Oncology. Other participating institutions included the Tampere University of Technology, Tampere, Finland, and the Institute for Systems Biology, Seattle.

About MD Anderson

The University of Texas MD Anderson Cancer Center in Houston ranks as one of the world's most respected centers focused on cancer patient care, research, education and prevention. MD Anderson is one of only 41 comprehensive cancer centers designated by the National Cancer Institute (NCI). For the past 25 years, MD Anderson has ranked as one of the nation's top two cancer centers in U.S. News & World Report's annual "Best Hospitals" survey. MD Anderson receives a cancer center support grant from the NCI of the National Institutes of Health (P30 CA016672).

For more information, visit mdanderson.org