Met-regulated expression signature defines a subset of human hepatocellular carcinomas with poor prognosis and aggressive phenotype

• Published in: The Journal of clinical investigation 2006-06, Vol.116 (6), p.1582-1595
• Main Authors: Kaposi-Novak, Pal, Lee, Ju-Seog, Gòmez-Quiroz, Luis, Coulouarn, Cédric, Factor, Valentina M, Thorgeirsson, Snorri S
• Format: Article
• Language: English
• Subjects: Angiogenesis; Animals; Biomedical research; Cancer; Carcinoma, Hepatocellular - diagnosis; Carcinoma, Hepatocellular - genetics; Carcinoma, Hepatocellular - metabolism; Carcinoma, Hepatocellular - pathology; Cells, Cultured; Data analysis; Datasets; Female; Gene expression; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Genetic aspects; Genomics; Hepatocyte Growth Factor - metabolism; Hepatocytes - cytology; Hepatocytes - physiology; Humans; Liver cancer; Liver Neoplasms - diagnosis; Liver Neoplasms - genetics; Liver Neoplasms - metabolism; Liver Neoplasms - pathology; Male; Medical prognosis; Medical research; Medicine, Experimental; Metastasis; Mice; Mice, Knockout; Middle Aged; Molecular Sequence Data; Motility; Neoplasm Metastasis; Oligonucleotide Array Sequence Analysis; Pathogenesis; Phenotype; Prognosis; Proto-Oncogene Proteins - genetics; Proto-Oncogene Proteins - metabolism; Proto-Oncogene Proteins c-met; Receptors, Growth Factor - genetics; Receptors, Growth Factor - metabolism; Survival Rate; Tumors
• ISSN: 0021-9738; 1558-8238
• DOI: 10.1172/JCI27236

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.