In addition to impacting cancer risk, mutations in the BRCA1 gene also have a role in determining whether a patient responds to certain types of therapies.

In a new publication, Neil Johnson, PhD, an assistant professor in the Molecular Therapeutics Program at Fox Chase Cancer Center, found that cancers with different types of BRCA1 mutations have varying susceptibilities to biological pathways that induce resistance to PARP inhibitors, an emerging class of cancer drugs.

The paper appears in the journal Cell Reports.

“PARP inhibitor resistance is a challenge in treating cancers, and we report in this paper that a common mechanism of resistance may be more likely to arise in cancers with specific classes of BRCA1 mutations,” Johnson said. “BRCA1-mutant cancers that are less receptive to this resistance mechanism could have prolonged therapeutic benefit from PARP inhibitor treatments.”

Johnson said future research would be needed to assess potential relationships between specific BRCA1 mutations and particular PARP inhibitor resistance pathways in order to determine the best treatment course for each patient.

Presently, three PARP inhibitors are FDA-approved, and several others are being tested in clinical trials.

Women with a BRCA1 mutation are about six times more likely to be diagnosed with breast cancer and more than 30 times more likely to be diagnosed with ovarian cancer.

Source: Fox Chase Cancer Center