Androgens regulate protein CD24, needed for tumor metastasis
Bladder cancer patients whose tumors express high levels of the protein CD24 have worse prognoses than patients with lower CD24. A University of Colorado Cancer Center study published today in the Proceedings of the National Academy of Sciences shows that CD24 expression may depend on androgens - and that anti-androgen therapies like those currently used to treat prostate cancer may benefit bladder cancer patients.
"This is a major finding - bladder cancer development and spread to other organs depends significantly on CD24, which in turn depends on androgens like testosterone. By taking away these androgens, we may be able to greatly diminish the proliferative and metastatic power of bladder cancer cells," says the study's senior author, Dan Theodorescu, MD, PhD, director of the University of Colorado Cancer Center.
Theodorescu and colleagues started with mouse models, showing that mice without the ability to make the protein CD24 had fewer primary bladder tumors and metastases (bladder tumor spread to other organs) compared to mice with CD24 intact. This effect was most marked in male mice. The group moved to human tumor samples, showing that when patients were stratified according to the levels of CD24 expressed in their tumors, especially the male patients had poorer outcomes, including higher rates of relapse and shorter disease-free survival.