Fig. 3.

Silencing of ST6GAL1 gene inhibits the invasive ability and chemoresistance of MHCC97H cells both in vitro and in vivo. A, silencing of ST6GAL1 in MHCC97H cells was analyzed via an RNAi approach. ST6GAL1 transcripts were decreased apparently by shRNA treatment in MHCC97H cells. B, after shRNA transfection, a distinct reduction of ST6GALI was observed at the protein level in Western blot analysis. C, differential FITC-SNA binding profiles of MHCC97H, MHCC97H-control shRNA, and MHCC97H-ST6GAL1 shRNA1 cell lines using flow cytometry. Histograms of fluorescence intensities of cells with specific carbohydrate expression as determined. D, in vitro ECMatrix gel analysis was performed. The average number of cells that invaded through the filter was counted. MHCC97H-ST6GAL1 shRNA1 cells were significantly less invasive (*p < 0.05) than the MHCC97H and MHCC97H-control shRNA cells. E, cell chemosensitivity was assessed via MTT assay. The reported values were the IC₅₀ (mean ± S.D.) of three independent experiments (IC₅₀ represents the drug concentration producing a 50% decrease in cell growth). *p < 0.05 versus MHCC97H-control shRNA cells. F, a decrease in mean tumor weight was observed in mice with MHCC97H-ST6GAL1 shRNA1 tumors relative to the control group (*p < 0.05). G, reduced regulation of ST6GALI was also shown by IHC staining in xenograft tumors derived from MHCC97H-ST6GAL1 shRNA1 cells (400×). The data are means ± S.D. of three independent assays (*p < 0.05).