SMAD3 and neoplasm: A series of tumour-associated proteins, such as vascular endothelial growth factor A (VEGF-A), small mothers against decapentaplegic homologue 3 (SMAD-3), matrix metalloprotease 2 (MMP-2), GATA-binding protein 2 (GATA2), and regulator of G protein signalling 7 and 8 (RGS-7/8), have been found or assumed to be related to the antitumour activities of chebulinic acid [15, 16, 32, 33].