Immunotherapy has revolutionized cancer treatment, yet most patients do not respond. While tumor antigens are needed for effective immunotherapy, a favorable tumor immune microenvironment is also critical. In this review, we discuss emerging evidence that tumor cells exploit cellular plasticity and dedifferentiation programs to avoid immune surveillance, which in turn drives metastatic dissemination and resistance to immunotherapy. A deeper understanding of these programs may provide novel opportunities to enhance the efficacy of existing immunotherapies.
©2020 American Association for Cancer Research.