Mechanism of shikonin inhibiting the proliferation of hepatocellular carcinoma cell
Objective To investigate the molecular mechanism of shikonin in inhibiting the proliferation of hepatocellular carcinoma(HCC)cells.Methods HepG2 human HCC cells were divided into six groups:control,low-dose shikonin,high-dose shikonin,miR-181c negative control(NC),miR-181c-inhibitor,and miR-181c-mimic groups.Cells were treated respectively with 2.5 or 5.0 μmol/L concentrations of shikonin,and transfected with miR-181c inhibitor or miR-181c mimics,respectively.Cell proliferation was detected using the cell counting kit-8(CCK-8)assay,while apoptosis was assessed by flow cytometry.The relative mRNA expression levels of miR-181c and non-SMC condensin I complex subunit G(NCAPG)were measured by qRT-PCR,and the relative protein expression levels of NCAPG and B-cell lymphoma 2(Bcl-2)were determined by Western blot.Results Compared with the control group,the cell proliferation rate was significantly reduced in both the high-dose and low-dose shikonin groups(both P<0.05),and that of the high-dose group reduced more remarkably than the low-dose group(P<0.05).In comparison to the miR-181c NC group,the cell proliferation rate significantly increased in the miR-181c inhibitor group,while significantly decreased in the miR-181c mimic group(both P<0.05).The high-dose group exhibited a significantly higher apoptosis rate than both the low-dose group and control group(both P<0.05).Compared with the miR-181c NC group,the apoptosis rate significantly decreased in the miR-181c inhibitor group,while significantly increased in the miR-181c mimic group(both P<0.05).The relative expression level of miR-181c mRNA in the high-dose group was significantly higher than that of the low-dose and control groups(both P<0.05).Compared to the miR-181c NC group,the miR-181c mRNA relative expression level significantly decreased in the miR-181c inhibitor group,while significantly increased in the miR-181c mimic group(both P<0.05).The relative expression levels of NCAPG mRNA,NCAPG and Bcl-2 proteins in the high-dose group were significantly lower than those of the low-dose group and control group(all P<0.05).Compared to the miR-181c NC group,the relative expression levels of NCAPG mRNA,NCAPG and Bcl-2 proteins significantly increased in the miR-181c inhibitor group,while significantly decreased in the miR-181c mimic group(all P<0.05).Conclusion Shikonin can upregulate miR-181c expression in HCC cells,thereby inhibiting the proliferation of HCC cells.