Like prostate cancer, bladder cancer patients may benefit from anti-androgen therapy

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 – 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 ," 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 ( 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.

"To us, these sex-specific findings implied androgen involvement," Theodorescu says. Sure enough, when the group knocked down in human bladder cancer cell lines, they saw a corresponding drop in CD24 levels and also decreased cell proliferation. When they artificially added CD24, resumed regardless of androgen levels. In essence, androgen is effectively a hormonal switch that allowed the harmful effect of CD24 to flow.

Together, these finding imply not only a correlative but a causative effect of CD24 – that not only do high levels of CD24 mark more aggressive bladder tumors, but that CD24 in fact drives the aggressiveness of these tumors. While the protein CD24 is difficult to affect directly with current therapies, anti-androgen therapies that would diminish the tumor's ability to express CD24 are already in wide use for prostate cancer.

"We hope the results of these studies show the rationale for clinical studies of anti-androgen therapies with bladder cancer, especially in those tumors that happen to test markedly high in CD24 expression," Theodorescu says. "The next step is moving this promising therapy to clinical trials with human patients."

Related Stories

Major study stops bladder cancer from metastasizing to lungs

Mar 12, 2012

The diagnosis of localized bladder cancer carries an 80 percent five-year survival rate, but once the cancer spreads, the survival rate at even three years is only 20 percent. A major study published today in the Journal of ...

Recommended for you

Survival differences seen for advanced-stage laryngeal cancer

17 hours ago

The five-year survival rate for advanced-stage laryngeal cancer was higher than national levels in a small study at a single academic center performing a high rate of surgical therapy, including a total laryngectomy (removal ...

Gene test aids cancer profile

Nov 27, 2014

The first round of chemotherapy did little to suppress Ron Bose's leukemia. The second round, with 10 times the dose, knocked the proliferating blast cells down, but only by half.

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.