CD70 molecule (CD70) is a gene that encodes a cytokine protein that functions as a ligand in the tumor necrosis factor (TNF) family. The protein functions in the induction of proliferation of co-stimulated T-cells. The protein also augments the generation of cytolytic T-cells and contributes to T-cell activation. Regulatory roles of the protein include the regulation of B-cell activation, cytotoxic function of natural killer cells, and immunoglobulin synthesis. Missense mutations, silent mutations, and frameshift deletions are observed in cancers such as bone cancer, intestinal cancer, and skin cancer.