Correlation between MET protein expression and MET gene copy number in a Caucasian cohort of non-small cell lung cancers according to the new IASLC/ATS/ERS classification. Issue 4 (June 2015)

• Record Type: Journal Article
• Authors: Weingertner, Noëlle; Meyer, Nicolas; Voegeli, Anne-Claire; Guenot, Dominique; Renaud, Stéphane; Massard, Gilbert; Falcoz, Pierre-Emmanuel; Olland, Anne; Mennecier, Bertrand; Gaub, Marie-Pierre; Lindner, Véronique; Ghnassia, Jean-Pierre; Quoix, Elisabeth; Chenard, Marie-Pierre; Beau-Faller, Michèle
• Is Part Of: Pathology. Volume 47:Issue 4(2015:Jun.)
• Publication Date: 2015-06
• Subjects: Pathology -- Periodicals; 616.0705
• DOI: 10.1097/PAT.0000000000000269
• Languages: English
• ISSNs: 0031-3025

Abstract

<abstract> <title> <x xml:space="preserve">Abstract</x> </title> <sec> <title>Summary</title> <p>MET pathway is a promising target in non-small cell lung cancers (NSCLC) requiring companion tests. The aim of this study was to compare MET expression/gene copy number in a Caucasian population of NSCLC patients.</p> <p>We analysed 201 NSCLC, with 141 adenocarcinomas classified according to 2011 IASLC recommendations, for MET expression by immunohistochemistry (IHC) and gene copy number (GCN) by silver <italic>in situ</italic> hybridisation (SISH) on tissue microarrays. Mutations in <italic>EGFR</italic>, <italic>KRAS</italic>, <italic>BRAF</italic>, <italic>HER2</italic>, <italic>PIK3CA</italic> genes and <italic>ALK</italic> rearrangements were determined.</p> <p>MET overexpression was observed in 44% and a high <italic>MET</italic> GCN (≥5 copies) in 14%. <italic>MET</italic> CGN was correlated with MET expression, regardless of IHC scores (<italic>p</italic> < 0.001) but only 31% of MET overexpressed cases were SISH positive. MET overexpression/GCN number was more frequent in ADC than the other types (<italic>p</italic> < 0.001), the highest in high grade (74%/34%) and sarcomatoid ADC (86%/43%). Mutations of current genes or ALK rearrangements were identified in overexpressed or amplified <italic>MET</italic> cases. MET overexpression was an independent prognostic factor for overall survival in non-smoker NSCLC in univariate (<italic>p</italic> = 0.01) and multivariate (<italic>p</italic> = 0.01) analyses.</p> <p>MET overexpression is more frequent than <italic>MET</italic> high GCN, particularly in high grade ADC, regardless of <italic>EGFR, KRAS, BRAF, HER2, PIK3CA</italic> and <italic>ALK</italic> status in NSCLC.</p> </sec> </abstract>