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Genomic alterations in lung adenocarcinoma displayed in Figure 2A.

Focal amplification and activating point mutation of the MET gene are well-characterized oncogenic drivers that confer susceptibility to targeted MET inhibitors. Recurrent somatic splice site alterations at MET exon 14 (METex14) that result in exon skipping and MET activation have been characterized, but their full diversity and prevalence across tumor types are unknown. Here, we report analysis of tumor genomic profiles from 38,028 patients to identify 221 cases with METex14 mutations (0.6%), including 126 distinct sequence variants. METex14 mutations are detected most frequently in lung adenocarcinoma (3%), but also frequently in other lung neoplasms (2.3%), brain glioma (0.4%), and tumors of unknown primary origin (0.4%). Further in vitro studies demonstrate sensitivity to MET inhibitors in cells harboring METex14 alterations. We also report three new patient cases with METex14 alterations in lung or histiocytic sarcoma tumors that showed durable response to two different MET-targeted therapies. The diversity of METex14 mutations indicates that diagnostic testing via comprehensive genomic profiling is necessary for detection in a clinical setting.Significance: Here we report the identification of diverse exon 14 splice site alterations in MET that result in constitutive activity of this receptor and oncogenic transformation in vitro. Patients whose tumors harbored these alterations derived meaningful clinical benefit from MET inhibitors. Collectively, these data support the role of METex14 alterations as drivers of tumorigenesis, and identify a unique subset of patients likely to derive benefit from MET inhibitors. Cancer Discov; 5(8); 850–9. ©2015 AACR.See related commentary by Ma, p. 802.See related article by Paik et al., p. 842.This article is highlighted in the In This Issue feature, p. 783

Summary of MET exon 14 alterations.

Previously characterized MET exon 14 alterations.

Focal amplification and activating point mutation of the MET gene are well-characterized oncogenic drivers that confer susceptibility to targeted MET inhibitors. Recurrent somatic splice site alterations at MET exon 14 (METex14) that result in exon skipping and MET activation have been characterized, but their full diversity and prevalence across tumor types are unknown. Here, we report analysis of tumor genomic profiles from 38,028 patients to identify 221 cases with METex14 mutations (0.6%), including 126 distinct sequence variants. METex14 mutations are detected most frequently in lung adenocarcinoma (3%), but also frequently in other lung neoplasms (2.3%), brain glioma (0.4%), and tumors of unknown primary origin (0.4%). Further in vitro studies demonstrate sensitivity to MET inhibitors in cells harboring METex14 alterations. We also report three new patient cases with METex14 alterations in lung or histiocytic sarcoma tumors that showed durable response to two different MET-targeted therapies. The diversity of METex14 mutations indicates that diagnostic testing via comprehensive genomic profiling is necessary for detection in a clinical setting. Significance: Here we report the identification of diverse exon 14 splice site alterations in MET that result in constitutive activity of this receptor and oncogenic transformation in vitro. Patients whose tumors harbored these alterations derived meaningful clinical benefit from MET inhibitors. Collectively, these data support the role of METex14 alterations as drivers of tumorigenesis, and identify a unique subset of patients likely to derive benefit from MET inhibitors. Cancer Discov; 5(8); 850–9. ©2015 AACR. See related commentary by Ma, p. 802. See related article by Paik et al., p. 842. This article is highlighted in the In This Issue feature, p. 783

The thermal decomposition of azomethane, CH 3 N=NCH 3 , and methylamine, CH 3 NH 2 ,on Pt(111) has been investigated by reflection absorption infrared spectroscopy (RAIRS) and temperature programmed reaction spectroscopy (TPRS). Using the surface dipole selection rule of RAIRS and comparing with the IR and Raman spectra of solid trans -and cis -azomethane, we find that trans -azomethane converts to cis -azomethane upon adsorbing onto the Pt(111) surface at 84 K. Additionally, we propose that the cis -azomethane tautomerizes to formaldehyde methylhydrazone, CH 3 NHN=CH 2 , which subsequently undergoes N-N bond cleavage between 200 and 275 K. Above 300 K aminomethylidyne, CNH 2 , is formed. Aminomethylidyne is also formed on the methylamine dosed surface. Cyanogen, C 2 N 2 (g), formed from the combination of CN ads was also observed by TPRS as a minor reaction product. A comparison of the IR spectra of azomethane and methylamine dosed surfaces indicates the formation of chemisorbed methylamine as one intermediate in the decomposition of azomethane.