DNA methylation is one of major factors in cancer progression. We observed multiple genes involved in cancer-related signaling and focused on patients with advanced non-small cell lung cancer (NSCLC) and evaluated methylation in relation to various clinical parameters.

Thirty genes were examined in 121 NSCLC patients using the methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) method. Correlations to gender, smoking status, tumor subtype, disease stage and EGFR/KRAS mutation status were performed by chi-square test.

90% of tumors exhibited methylation of at least one gene. Most frequently methylated were cadherin-13 (CDH13), Ras associated domain-containing protein (RASSF1A), Wilms' tumor protein (WT1), adenomatous polyposis coli protein (APC), paired box protein Pax-5 (PAX5), estrogen receptor (ESR1), an inhibitor of cyclin-dependent kinase p15 (CDKN2B), paired box protein Pax-6 (PAX6), transcription factor GATA-5 (GATA5) and cell adhesion molecule 4 (IGSF4). Overall methylation (any gene) was increased in adenocarcinomas (p=0.0329), unrelated to gender or disease stage. Several genes exhibited variable methylation with gender (CDH13, p<0.001; GATA5, p=0.02; PAX6, p=0.01 and ESR1, p=0.03), smoking (CDH13, p=0.002), or epidermal growth factor receptor (EGFR) mutation status [Von Hippel-Lindau disease tumor supresor (VHL), p=0.001; CDKN2B, p=0.02; CDH13, p=0.02; APC, p=0.04 and ESR1, p=0.04].

Differences in gene methylation associated with gender, smoking and EGFR mutation suggest potential for prediction in relation to management of tyrosine kinase inhibitor therapy.

PMID: 22199344 [PubMed - indexed for MEDLINE] Source: National Library of Medicine.