Quantification of DNMT1 and G9a mRNA levels in a panel of 38 human NSCLC cell lines by qPCR revealed, as a general trend, higher levels of DNMT1 than G9a. Expression of both genes was higher in cancer cells than in non-malignant cells (SAEC cells) (Fig. 1D). Here, DNMT1 is linked to non-small cell lung carcinoma.