Genetic Discovery Could Help Guide Doctors' Treatment of Bladder Cancers

Finding Highlights Potential of Precision Medicine to Personalize Clinical Care

By Pete Farley    | | October 17, 2013

Genetic Discovery Could Help Guide Doctors' Treatment of Bladder Cancers

A UC San Francisco-led team of scientists has discovered that a gene mutation found in some bladder cancers is indicative of low-risk tumors that are unlikely to recur or progress after surgery.

The finding could help doctors spare many patients from uncomfortable, expensive follow-up tests.

The study, reported online in the journal Nature Genetics on Oct. 13 offers a glimpse into the potential of precision medicine, which aims to use genetic information to make an accurate analysis of an individual’s disease and target it with precise therapy.

The fifth most common malignancy in the U.S., bladder cancers claim about 15,000 lives each year.

A majority of bladder cancers known as papillary tumors can be successfully treated with surgery, but about 20 percent recur and invade the muscle wall of the bladder or spread to nearby organs and lymph nodes. Thus far, physicians have not had an accurate method to determine which papillary tumors are potentially lethal, so most patients undergo frequent endoscopic examinations of their bladder using a technique known as cystoscopy to look for signs of recurrence.

Homing In on the STAG2 Gene
In 2011, while at Georgetown University School of Medicine, David A. Solomon, MD, PhD, his mentor Todd Waldman, MD, PhD, and colleagues published research in Science showing that mutations that deactivate a gene called STAG2 – which regulates the separation of duplicate chromosomes during cell division – are present in a range of human cancers.

Now a UCSF resident in anatomic pathology in the Department of Pathology, Solomon built on that work for the new Nature Genetics study.

Along with colleagues C. David James, PhD, Tomoko Ozawa, MD, PhD, and Joanna J. Phillips, MD, PhD, all of UCSF’s Department of Neurological Surgery, and other scientists from around the U.S. and from Germany, Solomon showed that inactivating mutations in the STAG2 gene are present in 36 percent of noninvasive papillary bladder tumors, but in only 16 percent of the recurrent, invasive variety.