RT Journal Article
SR Electronic
T1 Telomerase (h-TERT) and targeting EGFR in non small cell lung carcinoma: A combined immunohistochemistry and chromogenic in situ hybridization study based on tissue microarrays
JF European Respiratory Journal
JO Eur Respir J
FD European Respiratory Society
SP p1488
VO 38
IS Suppl 55
A1 Athanassios Stamatelopoulos
A1 Evangellos Tsiambas
A1 Petros Michos
A1 Ioannis Gakidis
A1 Andreas Karameris
A1 Dimosthenes Bouros
YR 2011
UL http://erj.ersjournals.com/content/38/Suppl_55/p1488.abstract
AB Purpose: Our aim was the evaluation of EGFR gene and protein alterations in NSCLC and the potential role of telomerase in the regulation of its expression.Methods: Using tissue microarray technology, forty (n=40) paraffin embedded histologically confirmed primary NSCLCs were cored twice at a diameter of 1mm and re-embedded into a recipient block. Immunohistochemistry was performed by the use of monoclonal antibodies anti-EGFR (31G7), and anti-telomerase/h-TERT (44F12). Also, a Chromogenic in situ hybridization protocol was applied based on the use of EGFR gene and chromosome 7 centromeric probes. Computerized Image Analysis was performed for the evaluation of immunohistochemistry results.Results: EGFR overexpression was observed in 23/40 (57.5%) cases correlating to stage (p=0.001) and histological type (p=0.04). Telomerase was overexpressed in all examined cases (high and moderate levels) correlating to stage (p=0.001). A significant value of concordance (kappa=0.686, 0.677-0.695) was assessed comparing telomerase and EGFR protein expression. EGFR gene amplification was identified in 2/40 (5%) cases associating to histological type (p=0.027) and chromosome 7 aneuploidy in 7/40 (17.5%) cases.Conclusions: NSCLC is characterized by rare cases of EGFR gene amplification and this genetic event maybe affect the efficacy of targeted therapeutic strategies based on monoclonal antibodies. Also, the strong concordance between EGFR and telomerase overexpression demonstrates that the enzyme is potentially involved in the growth-controlling gene expression.