Source: Medical Xpress, March 2017
It’s what’s missing in the tumor genome, not what’s mutated, that thwarts treatment of metastatic melanoma with immune checkpoint blockade drugs, researchers at The University of Texas MD Anderson Cancer Center report in Science Translational Medicine.
Whole exome sequencing of tumor biopsies taken before, during and after treatment of 56 patients showed that outright loss of a variety of tumor-suppressing genes with influence on immune response leads to resistance of treatment with both CTLA4 and PD1 inhibitors.
The team’s research focuses on why these treatments help 20-30 percent of patients—with some complete responses that last for years – but don’t work for others. Their findings indicate that analyzing loss of blocks of the genome could provide a new predictive indicator.read the original full article