These miRNAs are important negative regulators of the expression of tumor suppressor genes such as PTEN (phosphatase and tensin-like protein), TGFBR2 (transforming growth factor beta receptor 2), SMAD4 (mothers against decapentaplegic homolog 4), and p21 (cyclin-dependent kinase 2 inhibitor). The gene discussed is SMAD4; the disease is neoplasm.