July 31, 2014

New target for breast cancer therapy

The protein MTBP is overexpressed in an aggressive type of breast cancer, and it regulates another protein implicated in many cancer types, suggesting that it may be a good target for new therapeutics.

The protein MTBP is important for growth and survival of triple negative breast cancer (TNBC) – a clinically aggressive subtype of breast cancer that is commonly resistant to targeted therapeutics – Vanderbilt investigators have discovered.

Using data from The Cancer Genome Atlas, Christine Eischen, Ph.D., MSTP student Brian Grieb, Ph.D., and colleagues found that MTBP is overexpressed in breast cancer, with the highest levels in TNBC. They demonstrated that MTBP levels were elevated in a panel of human TNBC cell lines, and that reducing MTBP levels caused cell death and reduced tumor growth in vitro and in vivo in animal models, including in established tumors.

The researchers also found that MTBP is a novel regulator of MYC, an oncogenic factor that is overexpressed in 70 percent of human cancers. They showed that MTBP associates with MYC and increases MYC-mediated cell growth and tumor development.

The findings, published in two papers in Molecular Cancer Research and Cancer Research, position MTBP as a novel therapeutic target for human cancer, including TNBC.

This research was supported by grants from the National Institutes of Health (AG039164, GM007347, CA148950, CA098131, TR000445, CA068485, CA119925).

Send suggestions for articles to highlight in Aliquots and any other feedback about the column to