Figure 1.

Epigenetic silencing of LHX6 in lung cancer tissues and cell lines. (a) Representative results of LHX6 mRNA expression in tissues. LHX6 mRNA expression was significantly decreased in primary lung cancer tissues compared with that in the corresponding normal tissues as detected by RT-PCR. (b) mRNA expression of LHX6 in lung cancer cell lines was determined by semi-quantitative RT-PCR with β-actin as the internal control. LHX6 was weakly or not expressed in all lung cancer cell lines except for H1395. (c) Representative MSP results of the LHX6 methylation status in human tissues and cell lines. LHX6 was unmethylated in human normal lung tissues, but frequently hypermethylated in human lung cancer tissues and cell lines. MW, molecular weight; M, methylated product; U, unmethylated product; N, normal tissue; T, lung cancer tissue. (d) BGS analysis confirmed the methylation status of LHX6 in human tissues and cell lines. LHX6 was fully methylated in 95D cells, partially methylated in H358 and T122 cells, and unmethylated in normal tissue. (e) LHX6 mRNA expression was restored in lung cancer cell lines after treatment with the demethylation agent 5-aza-dC. ‘–' indicates DMSO control; and ‘+' indicates 5-aza-dC