Up-regulation of circ-SMARCA5 expression was sufficient to impede colon cancer cell viability and change of proteins associated with proliferation (p53, p21, and cyclinD1) and apoptosis (Bax and caspase-3), suggesting that circ-SMARCA5 could suppress the growth of colon cancer. The gene discussed is CASP3; the disease is malignant colon neoplasm.