Tissue-resident lymphocytes: sentinel of the transformed tissue

Tumor cells can be detected and cleared by lymphocytes in a process termed cancer immunosurveillance. However, the contributing cell types had not been fully characterized. Using oncogene-induced murine models of epithelial cancer, a recent study showed that cell transformation triggers expansion of tissue-resident lymphocytes derived from innate, T cell receptor (TCR) αβ and TCRγδ lineages. These type-1-like innate lymphoid cells (ILC1ls) and type 1 innate-like T cells (ILTC1s) share a gene expression program distinct from those of conventional lymphocytes, and exhibit cytolytic activities against tumor cells. Further deciphering such a tumor-elicited immunosurveillance mechanism may 1 day be harnessed for novel cancer immunotherapy.