Cancer-Causing Mutations Also Boost Tumor Immunoresistance

Mutations in the Ras gene are double trouble. Not only do they drive 25% of human cancers, they also suppress the immune system’s anticancer response. Essentially, these mutations turn good cells bad, and they also help bad cells masquerade as good cells by boosting the expression of a protein called PD-L1, or programmed death-ligand 1.PD-L1, which is ordinarily expressed in small amounts in the body, serves to prevent the immune system from attacking healthy cells. But PD-L1 can also be e