Abstract 2215: Use of peptide nucleic acid(PNA)-mediated PCR clamping method for detection EGFR mutation in patients with non-small cell lung cancer

Abstract

Abstract Introduction : Somatic mutations in the epidermal growth factor receptor (EGFR) kinase domain are associated with sensitivity to EGFR-tyrosine kinase inhibitors (EGFR-TKIs) in patients with nonsmall cell lung cancer (NSCLC). Direct sequencing is known to be the standard for detecting EGFR mutations; however, it has limited sensitivity. Peptide nucleic acids (PNA)-mediated Real-Time PCR clamping method is a newly introduced method for analyzing EGFR mutations with increased sensitivity and stability. Methods : Clinical specimens from 240 NSCLC patients were analyzed for EGFR mutations in exons 18, 19, 20 and 21. All clinical data and tumor specimens were obtained from 8 centers of Korean Molecular Lung Cancer Group (KMLCG). After genomic DNA extracted from paraffin-embedded tissue specimens, both PNA-mediated Real-Time PCR clamping and direct sequencing were performed. The results and clinical response to EGFR-TKIs were compared. Results : Sequencing revealed a total of 63(26.3%) mutations and PNA-mediated RT PCR clamping detected EGFR kinase mutation in 83(34.6%) samples. 61 mutations were consistent by both of direct sequencing and PNA-mediated RT PCR, however PNA-mediated RT PCR detected additional 22 mutations; 10 in exon 19, 9 in exon 21 and 3 in both of them. Furthermore, patients whose tumors expressed EGFR mutations exhibited an excellent response to EGFR-TKIs by more than 88%. Conclusion : PNA-mediated Real-Time PCR clamping is a simple and rapid, as well as a more sensitive method for screening of genomic alterations in EGFR gene compared to direct sequencing. This data suggests that PNA-mediated Real-Time PCR clamping should be implemented as a useful screening tool for detection of EGFR mutations in clinical setting. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2215. doi:10.1158/1538-7445.AM2011-2215