Copy Number Variation in Tumor Cells and Extracellular DNA in Patients with Lung Adenocarcinoma

Abstract

Copy number variation of some gene loci in lung tumor cells extracted by laser capture microdissection and in cell-free DNA in the plasma of patients with lung cancer was analyzed for identification of potential molecular markers. Tissue specimens fixed in formalin and embedded in paraffin blocks (FFPE-blocks) from 90 patients and extracellular DNA from plasma samples of 70 patients and 30 donors were used. Copy number variation was assayed for 30 genes (BAX, BCL2, C-FLAR, P53, MDM2, CASP9, CASP3, CASP8, SOX2, OCT4, PIK3, MKI67, HV2, HIF1A1, XRCC1, MMP1, TERT, CTNNB1, KRAS, EGFR, GRB2, SOS1, MAPK1, STAT1, BRAF, FTO, and mir3678) and reference loci (ACTB, B2M, and GAPDH) by the real-time quantitative PCR. Changed copy numbers were detected for genes responsible for apoptosis regulation (BAX, P53, and CASP3), proliferation (SOX2), DNA reparation (XRCC1), oxidative phosphorylation (HV2), EGFR signaling pathway (GRB2, SOS1, MAPK1, STAT1, and BRAF), and for mir3678 gene in lung tumor cells and extracellular DNA.