Fig. 1

miR-493 was down-regulated due to the aberrant DNA hype-methylation in lung cancer cell lines. a Real-time PCR was used to test the miR-493 expression in a panel of lung cancer cell lines including A549, A549/DDP and 95D. Each experiment was independently repeated at least 3 times. b MiR-493 expression in A549, A549/DDP and 95D cell lines after treatment of 2 μM and 5 μM 5-AZA-dC was determined by real-time PCR and the relative miR-493 expression value was indicated. c IC50 values of cells to DDP calculated from MTT assays showing the effects of 5-AZA-dC on sensitivity to cisplatin in A 549, A549/DDP and 95D cells. Each experiment was independently repeated at least 3 times. Error bars correspond to the mean ± SD. (*p < 0.05). d Schematic map containing CpG islands (shaded area) of the miR-493 upstream 2Kb- − +300 bp region, as adapted from the MethPrimer website (upper panel), indicating the transcription start site (+1), Primers for methylation-specific PCR (MSP) and quantitative pyrosequencing were designed to study that CpG island. e Bisulfite sequencing analysis was performed on miR-493 (+54 to +156) in lung cancer cells. Each horizontal row represents a single clone; the methylation percentages of 5 individual clones were indicated. The white and black circles represent the unmethylated and methylated CpG sites, respectively. f The methylation percentage of each cell line was shown. Error bars correspond to the mean ± SD. (*p < 0.05)