Inhibin subunit beta A (INHBA)

Inhibin subunit beta A is a protein encoded by the INHBA gene and is a member of the transforming growth factor-beta (TGF-β) superfamily[1][2][4][5]. It forms the βA subunit of activin and inhibin dimers, which play foundational roles in regulating secretion of follicle-stimulating hormone (FSH) from the pituitary gland, modulating cell proliferation and differentiation, and controlling developmental and physiological processes in multiple tissues[1][2][5]. Dysregulation of INHBA expression, especially in the form of activin A, is implicated in promoting tumor progression, invasion, and poor clinical outcomes in several cancers, making it a candidate therapeutic target and disease biomarker[2][3][4][5]. The protein also influences immune responses, reproductive physiology, and tissue development, and signals primarily through canonical TGF-β receptor/SMAD pathways along with non-canonical signaling pathways[5].

Other names

Inhibin beta A chainActivin beta-A chainErythroid differentiation protein (EDF)FSH-releasing protein (FRP)Inhibin, beta-1Erythroid differentiation factorFollicle-stimulating hormone-releasing proteinInhibin beta A subunitInhibin, beta A (activin A, activin AB alpha polypeptide)

Inhibition of activin A/INHBA signaling—typically through ligand neutralization or receptor antagonism—to decrease cancer cell proliferation, invasion, and to modulate immune response[2][5]. Follistatin and other binding proteins inhibit activin signaling by direct sequestration[2].