UT Southwestern kidney center program researchers have uncovered how kidney cancer aggressiveness is determined.
According to the study, kidney cancer is the country’s sixth most common type of cancer affecting men and women. Under the direction of Dr. Payal Kapul, associate professor of pathology at UT Southwestern, and Dr. James Brugarolas, associate professor of internal medicine at UT Southwestern, the team of researchers had previously classified kidney cancers into those with mutations in the BAP1 gene, or those with mutations in the PBRM1 gene.
The team found tumors with the BAP1 mutations were “very aggressive,” but those with the PBRM1 mutations were not. Subsequent studies also showed that, of 1,400 patients, 90 percent possessing PBRM1 tumors were alive 10 years after having surgery for kidney cancer, as opposed to 40 percent of those with BAP1 tumors.
To determine whether BAP1 and PBRM1 mutations were not only associated with, but responsible for the difference in aggressiveness, researchers engineered mice with mutations in either the BAP1 or PBRM1 in their kidneys. Researchers found mice with BAP1 mutations developed kidney cancer in three months, while mice with PBRM1 mutations developed tumors in more than nine months.
“These results show that the BAP1 and PBRM1 genes are responsible for more aggressive and less aggressive kidney cancers, respectively,” Brugarolas said in a statement.
By developing a mouse model of kidney cancer, researchers can now find new treatments. Researchers have already developed a test that allows patients to find out whether or not their tumor in a BAP1 mutant. “While only 10-20 percent of kidney cancers are the BAP1 type, patients are often anxious to know,” Kapur said.
