Figure 6

Effects of CpG island methylation status and copy number amplification on MALAT1 expression level. (A) Methylation status of the CpG island in a representative pair of clinical tissues, assessed by bisulfite sequencing. Open and filled squares denote un-methylated and methylated CpG sites respectively; each row represents a single clone. (B) No obvious difference in CpG island methylation frequency was observed in the ten pairs of tissues. A paired Student’s t-test was performed to determine the statistical significance. (C) The expression level of MALAT1 and CDH1 in EC109 and EC9706 cells following treatment with demethylase agent 5-aza-cdR (0, 5, and 10 μM). (D) Genomic copy number of MALAT1 in tumor tissues calculated by AccuCopy™ system. Red bars represented samples with MALAT1 amplification in tumor tissues. (E) Relative expression level of MALAT1 (normalized to GAPDH) in the twelve pairs of tissues, which showed gene amplification in tumor tissues. *P < 0.05, **P < 0.01.