August 1, 2017 – Mismatch Repair


Anchor lead: The FDA has approved use of a drug based on a new way to characterize cancers, Elizabeth Tracey reports

If you’ve received a diagnosis of cancer, you may also have been told your cancer cells will be tested for a type of genetic aberration known as a mismatch repair defect. That’s because the FDA has just approved use of one type of antibody drug based on the presence of this defect. Drew Pardoll, director of the Bloomberg Kimmel Institute for Cancer Immunotherapy at Johns Hopkins, describes these cancers.

Pardoll: It’s a genetic subset of the cancer that because of a defect in the spell check system for fixing mistakes whenever DNA is copied. Those cancers have lots of mutations. If this is a cancer type that has fifty times more mutations because its spell check is defective then that should make it really really easy for the immune system to recognize it.  :29

Pardoll’s own work has led to this approval, and he notes that some cancers respond dramatically to therapy when they have a mismatch repair defect. At Johns Hopkins, I’m Elizabeth Tracey.