SULF1 and hepatocellular carcinoma: We also examined the killing effect of rapamycin with or without hSulf1 expression in SMMC-7721 cells, and the expression of p-AKT, p-ERK, Cyclin D1 and Survivin, and further demonstrated that hSulf-1 enhances the inhibitory effect of rapamycin on cell survival signaling and produces a synergic killing effect on HCC cells combined with rapamycin.