title: Primary tumor xenografts of human lung adeno and squamous cell carcinoma express distinct proteomic signatures.
abstract: Nonsmall cell lung carcinoma (NSCLC) accounts for 80% of lung cancers. The most prevalent subtypes of NSCLC are adenocarcinoma (ADC) and squamous cell carcinoma (SCC), which combined account for approximately 90%. Ten resected NSCLC patient tumors (5 ADC and 5 SCC) were directly introduced into severely immune deficient (NOD-SCID) mice, and the resulting xenograft tumors were analyzed by standard histology and immunohistochemistry (IHC) and by proteomics profiling. Mass spectrometry (MS) methods involving 1- and 2-dimensional LC-MS/MS, and multiplexed selective reaction monitoring (SRM, or MRM), were applied to identify and quantify the xenograft proteomes. Hierarchical clustering of protein profiles distinguished between the ADC and SCC subtypes. The differential expression of 178 proteins, including a comprehensive panel of intermediate filament keratin proteins, was found to constitute a distinctive proteomic signature associated with the NSCLC subtypes. Epidermal growth factor receptor (EGFR) was expressed in ADC and SCC xenografts, and EGFR network activation was assessed by phosphotyrosine profiling by Western blot analysis and SRM measurement of EGFR levels, and mutation analysis. A multiplexed SRM/MRM method provided relative quantification of several keratin proteins, EGFR and plakophilin-1 in single LC-MS/MS runs. The protein quantifications by SRM and MS/MS spectral counting were associated with superior dynamic range and reproducibility but were otherwise consistent with orthogonal methods including IHC and Western immuno blotting. These findings illustrate the potential to develop a comprehensive MS-based platform in oncologic pathology for better classification and potentially treatment of NSCLC patients.
authors.affiliation: Program in Molecular Structure and Function, Hospital For Sick Children, University Health Network, Ontario Cancer Institute/Princess Margaret Hospital, Toronto, Canada.
authors.forename: Yuhong
authors.initials: Y
authors.lastname: Wei
authors.forename: Jiefei
authors.initials: J
authors.lastname: Tong
authors.forename: Paul
authors.initials: P
authors.lastname: Taylor
authors.forename: Dan
authors.initials: D
authors.lastname: Strumpf
authors.forename: Vladimir
authors.initials: V
authors.lastname: Ignatchenko
authors.forename: Nhu-An
authors.initials: NA
authors.lastname: Pham
authors.forename: Naoki
authors.initials: N
authors.lastname: Yanagawa
authors.forename: Geoffrey
authors.initials: G
authors.lastname: Liu
authors.forename: Igor
authors.initials: I
authors.lastname: Jurisica
authors.forename: Frances A
authors.initials: FA
authors.lastname: Shepherd
authors.forename: Ming-Sound
authors.initials: MS
authors.lastname: Tsao
authors.forename: Thomas
authors.initials: T
authors.lastname: Kislinger
authors.forename: Michael F
authors.initials: MF
authors.lastname: Moran
mesh_terms: D000230:Adenocarcinoma / Q000378:metabolism*; D000818:Animals; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000378:metabolism*; D002853:Chromatography, Liquid; D016000:Cluster Analysis; D066246:ErbB Receptors / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D053552:Keratin-7 / Q000378:metabolism; D007633:Keratins / Q000378:metabolism; D051379:Mice; D016688:Mice, Inbred NOD; D009368:Neoplasm Transplantation; D020543:Proteome / Q000032:analysis / Q000378:metabolism*; D015203:Reproducibility of Results; D018709:Statistics, Nonparametric; D053719:Tandem Mass Spectrometry; D014183:Transplantation, Heterologous
chemical_list: C507497:KRT7 protein, human; D053552:Keratin-7; D020543:Proteome; D007633:Keratins; D066246:ErbB Receptors