In an act of defiance, cancer cells produce enzymes that cleave these anchored proteins, essentially shedding the proteins and evading detection.
Lucas Ferrari de Andrade et al. suspected that it would be possible to stop tumors from shedding these proteins using antibodies that target the site where MICA and MICB proteins are cleaved.
‘New way to stop tumors from shedding certain proteins that the immune system uses to identify and attack tumors has been identified by scientists.’
They studied the effect of such an antibody, mAb 7C6, in mouse models of melanoma and lung cancer, finding that the antibody not only increased the presence of MICA and MICB on cancer cells, but also increased the infiltration of natural killer cells within tumors.
In mice with metastatic melanoma that had spread to the lungs, treatment with mAb 7C6 helped reduce tumor load, the authors report. In a related Perspective, Adelheid Cerwenka and Lewis Lanier write, "The study introduces an exciting concept for a therapeutic monoclonal antibody with the potential to improve natural killer cell-based cancer immunotherapy."