TGFB1 and neoplasm: Member of the TGFB family of cytokines; interferes with antitumor immune responses; has suppressive effects of interleukin-2 dependent T-cell growth; responsible for the down-regulation of the activating immunoreceptor NKG2D expression in CD8(+) T and NK cells and suppression of their lytic functions; may act directly as a tumor progression factor