KDR and hepatocellular carcinoma: In this study, by constructing various vectors carrying the hSulf-1 gene, hSulf-1 small hairpin RNA (shRNA) or VEGFR-2 shRNA, we provided evidence to demonstrate that the hSulf-1 re-expression exhibited a negative effect on cell growth by downregulating VEGFR-2 signaling both in ovarian cancer and hepatocellular carcinoma cell lines.