Fig. 3

Methylation status of Hsa-miR-9 genes in EOC cells and their effects on the paclitaxel sensitivity. a. BSP results of the hsa-miR-9-1 CpG island region in two pairs of paclitaxel sensitive and resistant EOC cell lines. 10 clones were sequenced for each cell line. Each circle indicates a CpG dinucleotide, black circle: methylated CpG; open circle: unmethylated CpG. b. BSP results of the hsa-miR-9-2 CpG island region in two pairs of paclitaxel sensitive and resistant EOC cell lines. 10–12 clones were sequenced for each cell line. c. BSP restuls of the hsa-miR-9-3 CpG island region in two pairs of paclitaxel sensitive and resistant EOC cell lines. 11 clones were sequenced for each cell line. d. MSP of three hsa-miR-9 genes in different ovarian carcinoma cell lines. e. Real-time RT-PCR analysis of miR-9 in ST30 cell lines treated with or without DAC. Low miR-9 expression in ST30 cells was restored by DAC (P = 0.000). f. The effect of DAC and miR-9 inhibitor on the paclitaxel sensitivity of ST30 cell lines. The inhibited rates of paclitaxel on ST30 cell lines treated with or without miR-9 inhibitor, DAC combined with miR-9 inhibitor or DAC were assessed by MTS assay and the IC50 values were 3295.54 ± 154.87nM, 2590.36 ± 126.68nM, and 2057.35 ± 13.54nM in turn, compared with control (IC50 = 2898.94 ± 155.75 nM), P = 0.001, 0.056 and 0.035 in turn. The experiments were repeated three times