However, studies of the association between DNMT expression and clinical outcome in NSCLC patients have produced inconsistent results (Kim et al, 2006; Vallbohmer et al, 2006; Lin et al, 2007), and few have evaluated the prognostic value of MBD2. Therefore, we determined the expression of DNMT1, DNMT3b, and MBD2 by real-time quantitative PCR in 148 tumour samples from NSCLC patients and analysed their prognostic value, both separately and jointly. This evidence concerns the gene DNMT1 and non-small cell lung carcinoma.