DCB-3503

**DCB-3503** is a synthetic small-molecule **tylophorine analogue** with potent antitumor activity. It inhibits growth of various tumor cell lines in vitro and in vivo, including human pancreatic (PANC-1) and hepatocellular (HepG2) carcinomas. Unlike typical cytotoxic agents, DCB-3503 induces cell differentiation rather than cell death. Its primary mechanism of action is the inhibition of protein synthesis, primarily by reducing the rate of polypeptide chain elongation rather than affecting mTOR signaling or protein degradation pathways. DCB-3503 preferentially downregulates proteins with short half-lives—such as cyclin D1, survivin, β-catenin, p53, and p21—without significantly reducing their mRNA levels. Research has identified **heat shock cognate protein 70 (HSC70)** as a molecular target: DCB-3503 binds this chaperone, disrupts its interaction with mRNA and the miRNA processing complex, and thereby inhibits translation efficiency for select transcripts (notably cyclin D1). DCB-3503 also inhibits the nuclear factor-kappaB (NF-κB) pathway by reducing phosphorylated p65 and nuclear IκB kinase alpha, and has demonstrated activity in animal models of cancer, lupus, and arthritis[1][2][3][4][5].

Other names

DCB-3503DCB3503DCB 3503tylophorine analogue