The Tale of Transforming Growth Factor-Beta (TGF beta) Signaling: A Soigne Enigma

Transforming growth factor-beta (TGF beta) is a secreted cytokine, which intricately controls a plethora of physiological and pathological processes during development and carcinogenesis. TGF beta exerts antiproliferative effects and functions as a tumor suppressor during early stages of tumorigenesis, whereas at later stages it functions as a tumor promoter aiding in metastatic progression through an autocrine TGF beta loop. Intricate knowledge of TGF beta signaling and its regulation are still evolving. In this review, we make an attempt to showcase the associated enigma of TGF beta signaling in its dual functional role as tumor suppressor and metastatic promoter during early and late stages of carcinogenesis, respectively. (C) 2009 IUBMB IUBMB Life, 61(10): 929-939, 2009