Saururus chinensis Baill inhibits proliferation and invasion of human renal cell carcinoma cells through inhibition of inhibitor of apoptosis protein.

OBJECTIVE: To investigate the inhibitory effect of Saururus chinensis Baill on cell viability, apoptosis, invasion capacity and the mechanism involved in human renal cell carcinoma (RCC) cells.

METHODS: After treating A498 and ACHN cells with Saururus chinensis Baill extract (0, 25, 50 μg/mL), inhibitory effect of Saururus chinensis Baill were evaluated using tetrazolium salt-based colorimetric assay, flfl ow cytometry analysis, and in vitro Matrigel invasion assay, respectively. To determine the molecular mechanisms of Saururus chinensis Baill, expression of inhibitor of apoptosis proteins (IAP) were assessed using reverse transcription polymerase chain reaction (RT-PCR) and Western blot. The levels of cytochrome C and caspase-3 proteins were assessed by Western blot.

RESULTS: Saururus chinensis Baill suppressed cell viability and invasion capacity and induced apoptosis of A498 and ACHN cells in a time- and concentration-dependent manner. RT-PCR and Western blot analysis showed that Saururus chinensis Baill inhibited the expressions of cellular inhibitor of apoptosis (cIAP)-1, cIAP-2, X-linked inhibitor of apoptosis protein, and survivin. This was accompanied by the release of cytochrome C and activation of caspase-3 proteins.

CONCLUSIONS: Saururus chinensis Baill can inhibit human RCC cell growth by inducing cancer cell apoptosis, and these effects are mediated by the down-regulation of IAP proteins and subsequent release of cytochrome C and activation of caspase-3.