SMAD3 and neoplasm: We focused on some important events, for example, pathways of oncogenesis by Met, EIF4 pathway, downregulation of SMAD2-SMAD3-SMAD4 transcriptional activity, EZH2 targets, stemness, well vs. poorly differentiated tumor, epithelial mesenchymal transition, UV response via ERCC3, and metastasis.