Gene Deletions and Amplifications in Human Hepatocellular Carcinomas

Department of Pathology, Graduate School of Public Health, University of Pittsburgh, Pittsburgh, Pennsylvania 15241, USA.
American Journal Of Pathology (Impact Factor: 4.59). 02/2012; 180(4):1495-508. DOI: 10.1016/j.ajpath.2011.12.021
Source: PubMed


Tissues from 98 human hepatocellular carcinomas (HCCs) obtained from hepatic resections were subjected to somatic copy number variation (CNV) analysis. Most of these HCCs were discovered in livers resected for orthotopic transplantation, although in a few cases, the tumors themselves were the reason for the hepatectomies. Genomic analysis revealed deletions and amplifications in several genes, and clustering analysis based on CNV revealed five clusters. The LSP1 gene had the most cases with CNV (46 deletions and 5 amplifications). High frequencies of CNV were also seen in PTPRD (21/98), GNB1L (18/98), KIAA1217 (18/98), RP1-1777G6.2 (17/98), ETS1 (11/98), RSU1 (10/98), TBC1D22A (10/98), BAHCC1 (9/98), MAML2 (9/98), RAB1B (9/98), and YIF1A (9/98). The existing literature regarding hepatocytes or other cell types has connected many of these genes to regulation of cytoskeletal architecture, signaling cascades related to growth regulation, and transcription factors directly interacting with nuclear signaling complexes. Correlations with existing literature indicate that genomic lesions associated with HCC at the level of resolution of CNV occur on many genes associated directly or indirectly with signaling pathways operating in liver regeneration and hepatocyte growth regulation.

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Available from: George Michalopoulos, Feb 27, 2014
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    • "Studies have shown that Rsu-1 has suppressive effects on growth of cancer cells namely glioblastoma and mammary cells [11,12,17]. From a totally separate study in our lab utilizing liver cancers, we also found that 10% of the HCC patients had deletions in Rsu-1 gene [13] further strengthening our hypothesis that Rsu-1 might be a major negative growth regulator for hepatocytes. Rsu-1 levels were also lower in PINCH DKO mice (Figure 2A). "
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