PT - JOURNAL ARTICLE AU - EVANGELOS TSIAMBAS AU - NICHOLAS S. MASTRONIKOLIS AU - ALICIA Y. LEFAS AU - STAVROS N. GEORGIANNOS AU - VASILEIOS RAGOS AU - PANAGIOTIS P. FOTIADES AU - NIKOLAOS TSOUKALAS AU - NIKOLAOS KAVANTZAS AU - ANDREAS KARAMERIS AU - DIMITRIOS PESCHOS AU - EFSTRATIOS PATSOURIS AU - KONSTANTINOS SYRIGOS TI - Chromosome 7 Multiplication in EGFR-positive Lung Carcinomas Based on Tissue Microarray Analysis DP - 2017 Jul 01 TA - In Vivo PG - 641--648 VI - 31 IP - 4 4099 - http://iv.iiarjournals.org/content/31/4/641.short 4100 - http://iv.iiarjournals.org/content/31/4/641.full SO - In Vivo2017 Jul 01; 31 AB - Background/Aim: Epidermal growth factor receptor (EGFR) over-activation is observed in significant proportions of non-small cell lung carcinomas (NSCLC). Our aim was to investigate the role of chromosome 7 multiplication with regard to its influence in EGFR expression, combined or not with gene amplification. Materials and Methods: Using tissue microarray technology, fifty (n=50) primary NSCLCs were cored and re-embedded into the final recipient block. Immunohistochemistry (IHC) and also chromogenic in situ hybridization (CISH) were performed. Results: EGFR expression at any level was detected in 40/50 (80%) cores. Over-expression was observed in 23/40 (57.5%) cases. Gene amplification was identified in 11/50 (22%) cases whereas chromosome 7 polysomy in 8/50 (16%) cases. Pure chromosome 7 multiplication alone led to low or moderate levels of expression. Overall EGFR expression was correlated with gene (p=0.001) and interestingly with chromosome 7 centromere numerical imbalances (p=0.004). Conclusion: EGFR expression is associated not only with amplification, but also with chromosome 7 centromere multiple copies. Chromosome 7 multiplication –due to centromere region amplification or true polysomy– is critical for applying monoclonal antibody targeted therapeutic strategies excluding the pure non-amplified cases.