Immunologic Targeting of Cancer Stem Cells.

Cancer stem cells (CSCs) are crucial for tumor recurrence and distant metastasis. Immunologically targeting CSCs represents a promising strategy to improve efficacy of multimodal cancer therapy. Modulating the innate immune response involving Toll-like receptors, macrophages, natural killer cells, and γδT cells has therapeutic effects on CSCs. Antigens expressed by CSCs provide specific targets for immunotherapy. CSC-primed dendritic cell-based vaccines have induced significant antitumor immunity as an adjuvant therapy in experimental models of established tumors. Targeting the tumor microenvironment CSC niche with cytokines or checkpoint blockade provides additional strategies to eliminate CSCs.