Transforming Growth Factor beta (TGF-beta) is a multifunctional cytokine and a member of a large family of cytokines that controls many aspects of cellular function, including cell proliferation, differentiation, migration, apoptosis, adhesion, angiogenesis, immunological surveillance and survival.
Related to cell proliferation and tumorigenesis, TGF-beta bears both a tumor-suppressor and a tumor-promotor activity. TGF-beta controls cell growth and motility in part through its regulation of tumor microenvironment and plays a key role in tumor development.
TGF-beta is expressed during development stages, regulating interactions between epithelial and mesenchymal cells, particularly in the lung, kidney, and mammary gland. Aberrantly, inadequate reactivation of the epithelial-mesenchymal transition (EMP) during tumorigenesis is now acknowledged to be a key process in the development of invasive and metastatic tumors.
Under normal conditions, TGF-beta is also a powerful suppressor of mammary epithelial cells (MEC) proliferation and thus an inhibitor of mammary tumo formation. However, aberrant genetic and epigenetic events in tumorigenesis cancel the cytostatic function of TGF-beta, which contributes to tumor progression.
Therapeutics designed to antagonise TGF-beta might be a good strategy to inhibit cancer progression and improve the prognosis and treatment of cancer patients.