γδ T-cell immunotherapy for lung cancer

Lung cancer is the leading cause of cancer death worldwide, yet there are still no satisfactory protocols available for treating this disease, emphasizing the urgency for more effective therapies. Recent clinical trials have provided encouraging evidence of the benefits of certain forms of immunotherapy. Here, we summarize recent developments in the area of γδ T-cell therapy for lung cancer in our center. γδ T cells constitute 2%-10% of T lymphocytes in human blood and play a role in immune surveillance against microbial pathogens and, possibly, cancer. These T cells recognize phosphoantigens via polymorphic γδ T-cell antigen receptors (TCR), as well as the major histocompatibility complex (MHC) class I chain-related molecules, A and B (MICA and MICB), via nonpolymorphic NKG2D receptors in an MHC-unrestricted manner. This implies that γδ T cells could retain antitumor effects despite reduced expression of MHC and tumor antigens on cancer cells. Thus, clinical trials have been conducted to evaluate the safety and efficacy of γδ T-cell-based immunotherapies for non-Hodgkin lymphoma, multiple myeloma, and solid tumors. This review focuses on the current status of γδ T-cell-based immunotherapy for lung cancer.