Expression of Repressive Histone Lysine Methyltransferases (H3K9-MTs and H3K27-MTs) is increased in lung cancer cell lines and after the immortalization and transformation in human bronchoepithelial cells. A. Quantitative RT-PCR shows mRNA expression of HKMTs are overexpressed in non-small cell lung cancer cell lines A549, Calu-1, SK-LU-1, SK-MES-1 and SW900 except for H3-K4 MT SET9 which remained at the same level compared to NHBE cells. Human glyceraldehyde-3-phosphate dehydrogenase (GAPDH) was used for normalization of cDNA input. Fold differences of mRNA expression compared with NHBE cells (arbitrarily assigned a value of 1). B. Quantitative RT-PCR analysis shows increased mRNA of SUV39H, SETDB1, G9A, EZH2 and DOT1L after immortalization by introduction of hTERT (hT) and SV40 large T antigen (LT) and transformation by introduction of activated H-Ras (Ras) compared with parental Normal Human Bronchoepithelial (NHBE) cells while transcription activating H3-K4 MTs (SET9 and SMYD3) mRNA expression stayed at a similar range compared to NHBE cells. Columns, average from duplicate wells.