Protein inactivation appears to halt prostate tumor progression

Inactivating the expression of GRP78, a specific biomarker for aggressive prostate cancer, appears to block its development in animal models, according to researchers from the University of Southern California, Los Angeles.

“This research has far-reaching implications in a wide range for human cancers,” said principal investigator Amy Lee, PhD. “It is a breakthrough study.”

The glucose-regulated GRP78 protein has been identified as a crucial entity in the development of prostate cancer by promoting cancer cell proliferation, mediating oncogenic signaling, and protecting cancer cells against cell death resulting from the stress of tumor development, according to Dr. Lee. By suppressing GRP78 expression or activity, she and colleagues found that they could block prostate cancer activation and development resulting from the loss of PTEN, a tumor suppressor gene for a number of human cancers.

The researchers spent more than 3 years monitoring prostate cancer development in animal models that had been genetically engineered to have both the GRP78 and PTEN tumor suppressor genes inactivated. Their findings will appear in an upcoming issue of the Proceedings of the National Academy of Sciences.