Effects and mechanism of Lanthanum Citrate on proliferation and apoptosis of human hepatocellular carcinoma cell line SMMC-7721

Abstract

Objective To investigate the effect and the possible mechanism of Lanthanum Citrate on the proliferation and apoptosis of human hepatocellular carcinoma cell line SMMC-7721 through the Hedgehog signaling pathway. Methods Hhsignaling pathway inhibitor KAAD-cyclopamine and Lanthanum Citrate in different concentrations were used to treat human hepatocellular carcinoma cell line SMMC-7721. Cell proliferation was detected by MTT method. The apoptosis rate was detected by Annexin V/PI flow cytometry. The expressions of the regulative genes, such as CyclinD1, p21, Caspase-3, Bcl-2, Gli1, Shh were detected by Western blot. The mRNA expressions of Gli1 and Shh were detected by q-PCR. Results In control group, SMMC-7721 cells were treated with 0.1 mmol/L Lanthanum Citrate group, and 15 μmol/L KAAD-cyclopamine for 48 h, and expression of CyclinD1 protein in each group was (1.41±0.21), (0.71±0.08) and (0.53±0.11); p21 protein was (0.49±0.08), (0.97±0.09) and (1.55±0.13); Caspase-3 protein was (0.36±0.05), (0.67±0.10) and (0.89±0.11); the relative expression of Bcl-2 protein in each group was (0.61±0.10), (0.48±0.05) and (0.24±0.08). Gli1, Shh mRNA and Gli1, Shh protein expression were decreased. AnnexinV-FITC double staining showed Lanthanum Citrate group and KAAD-cyclopamine group had increased apoptosis rate of SMMC-7721 cells by flow cytometry. Conclusion Lanthanum Citrate inhibits the proliferation and promotes apoptosis in hepatocellular carcinoma SMMC-772 cells through suppressing hedgehog signaling pathway. Key words: Hepatocellular carcinoma; Signaling pathway, Hedgehog; Lanthanum Citrate; Cell proliferation; Cell apoptosis