title: Met-regulated expression signature defines a subset of human hepatocellular carcinomas with poor prognosis and aggressive phenotype.
abstract: Identification of specific gene expression signatures characteristic of oncogenic pathways is an important step toward molecular classification of human malignancies. Aberrant activation of the Met signaling pathway is frequently associated with tumor progression and metastasis. In this study, we defined the Met-dependent gene expression signature using global gene expression profiling of WT and Met-deficient primary mouse hepatocytes. Newly identified transcriptional targets of the Met pathway included genes involved in the regulation of oxidative stress responses as well as cell motility, cytoskeletal organization, and angiogenesis. To assess the importance of a Met-regulated gene expression signature, a comparative functional genomic approach was applied to 242 human hepatocellular carcinomas (HCCs) and 7 metastatic liver lesions. Cluster analysis revealed that a subset of human HCCs and all liver metastases shared the Met-induced expression signature. Furthermore, the presence of the Met signature showed significant correlation with increased vascular invasion rate and microvessel density as well as with decreased mean survival time of HCC patients. We conclude that the genetically defined gene expression signatures in combination with comparative functional genomics constitute an attractive paradigm for defining both the function of oncogenic pathways and the clinically relevant subgroups of human cancers.
authors.affiliation: Laboratory of Experimental Carcinogenesis, Center for Cancer Research, National Cancer Institute, NIH, Bethesda, Maryland 20892, USA.
authors.forename: Pal
authors.initials: P
authors.lastname: Kaposi-Novak
authors.forename: Ju-Seog
authors.initials: JS
authors.lastname: Lee
authors.forename: Luis
authors.initials: L
authors.lastname: Gòmez-Quiroz
authors.forename: Cédric
authors.initials: C
authors.lastname: Coulouarn
authors.forename: Valentina M
authors.initials: VM
authors.lastname: Factor
authors.forename: Snorri S
authors.initials: SS
authors.lastname: Thorgeirsson
mesh_terms: D000818:Animals; D006528:Carcinoma, Hepatocellular / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D002478:Cells, Cultured; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D017228:Hepatocyte Growth Factor / Q000378:metabolism; D022781:Hepatocytes / Q000166:cytology / Q000502:physiology; D006801:Humans; D008113:Liver Neoplasms / Q000175:diagnosis / Q000235:genetics / Q000378:metabolism* / Q000473:pathology*; D008297:Male; D051379:Mice; D018345:Mice, Knockout; D008875:Middle Aged; D008969:Molecular Sequence Data; D009362:Neoplasm Metastasis; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D011379:Prognosis; D011518:Proto-Oncogene Proteins / Q000235:genetics / Q000378:metabolism*; D019859:Proto-Oncogene Proteins c-met; D017978:Receptors, Growth Factor / Q000235:genetics / Q000378:metabolism*; D015996:Survival Rate
chemical_list: C066855:HGF protein, human; D011518:Proto-Oncogene Proteins; D017978:Receptors, Growth Factor; D017228:Hepatocyte Growth Factor; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met