Project description:BACKGROUND & AIMS: Metabolic syndrome is a newly identified risk factor for hepatocellular carcinoma (HCC), however the molecular mechanisms still remain unclear. To elucidate this issue, cross-species analysis was performed to compare gene expression patterns of HCC from human patients and melanocortin 4 receptor-knockout (MC4R-KO) mice, developing HCC with obesity, insulin resistance and dyslipidemia. METHODS: Unsupervised hierarchical clustering and principle component analysis of 746 differentially expressed orthologous genes classified HCC of 152 human patients and MC4R-KO mice into two distinct subgroups, one of which included all the mouse HCC was etiologically associated with metabolic risk factors, such as obesity and diabetes. A specific biomarker was identified by the integrative analysis, and validated with in vitro studies and other cohort patients. RESULTS: As commonly overexpressed in human and mouse metabolic disease-associated HCC, FABP4 was remarkably enriched in intratumoral activated hepatic stellate cells (HSCs). Then, we established subclones constitutively expressing FABP4 from a human HSC cell line, in which the expression levels of inflammatory chemokines including IL1A and IL6 was upregulated through NF-κB nuclear translocation. An immunohistochemical validation study of other 106 human HCC samples indicated that FABP4-positive HSCs were distributed in tumors of 38 cases, and that the FABP4-high group was composed of patients with non-viral and non-alcoholic HCC (P=0.027) and with multiple metabolic risk factors (P<0.001) compared with the FABP4-low. CONCLUSIONS: FABP4 overexpression in HSCs could contribute to hepatocellular carcinogenesis in patients with metabolic risk factors via modulation of inflammatory pathway, and is a promising novel biomarker as well as a potential therapeutic target for this subtype of HCC.
Project description:BACKGROUND & AIMS: Metabolic syndrome is a newly identified risk factor for hepatocellular carcinoma (HCC), however the molecular mechanisms still remain unclear. To elucidate this issue, cross-species analysis was performed to compare gene expression patterns of HCC from human patients and melanocortin 4 receptor-knockout (MC4R-KO) mice, developing HCC with obesity, insulin resistance and dyslipidemia. METHODS: Unsupervised hierarchical clustering and principle component analysis of 746 differentially expressed orthologous genes classified HCC of 152 human patients and MC4R-KO mice into two distinct subgroups, one of which included all the mouse HCC was etiologically associated with metabolic risk factors, such as obesity and diabetes. A specific biomarker was identified by the integrative analysis, and validated with in vitro studies and other cohort patients. RESULTS: As commonly overexpressed in human and mouse metabolic disease-associated HCC, FABP4 was remarkably enriched in intratumoral activated hepatic stellate cells (HSCs). Then, we established subclones constitutively expressing FABP4 from a human HSC cell line, in which the expression levels of inflammatory chemokines including IL1A and IL6 was upregulated through NF-κB nuclear translocation. An immunohistochemical validation study of other 106 human HCC samples indicated that FABP4-positive HSCs were distributed in tumors of 38 cases, and that the FABP4-high group was composed of patients with non-viral and non-alcoholic HCC (P=0.027) and with multiple metabolic risk factors (P<0.001) compared with the FABP4-low. CONCLUSIONS: FABP4 overexpression in HSCs could contribute to hepatocellular carcinogenesis in patients with metabolic risk factors via modulation of inflammatory pathway, and is a promising novel biomarker as well as a potential therapeutic target for this subtype of HCC.
Project description:BACKGROUND & AIMS: Metabolic syndrome is a newly identified risk factor for hepatocellular carcinoma (HCC), however the molecular mechanisms still remain unclear. To elucidate this issue, cross-species analysis was performed to compare gene expression patterns of HCC from human patients and melanocortin 4 receptor-knockout (MC4R-KO) mice, developing HCC with obesity, insulin resistance and dyslipidemia. METHODS: Unsupervised hierarchical clustering and principle component analysis of 746 differentially expressed orthologous genes classified HCC of 152 human patients and MC4R-KO mice into two distinct subgroups, one of which included all the mouse HCC was etiologically associated with metabolic risk factors, such as obesity and diabetes. A specific biomarker was identified by the integrative analysis, and validated with in vitro studies and other cohort patients. RESULTS: As commonly overexpressed in human and mouse metabolic disease-associated HCC, FABP4 was remarkably enriched in intratumoral activated hepatic stellate cells (HSCs). Then, we established subclones constitutively expressing FABP4 from a human HSC cell line, in which the expression levels of inflammatory chemokines including IL1A and IL6 was upregulated through NF-κB nuclear translocation. An immunohistochemical validation study of other 106 human HCC samples indicated that FABP4-positive HSCs were distributed in tumors of 38 cases, and that the FABP4-high group was composed of patients with non-viral and non-alcoholic HCC (P=0.027) and with multiple metabolic risk factors (P<0.001) compared with the FABP4-low. CONCLUSIONS: FABP4 overexpression in HSCs could contribute to hepatocellular carcinogenesis in patients with metabolic risk factors via modulation of inflammatory pathway, and is a promising novel biomarker as well as a potential therapeutic target for this subtype of HCC.
Project description:The p53 protein is a cell-autonomous tumor suppressor that restricts malignant transformation by triggering cell cycle exit or apoptosis. p53 also promotes cellular senescence, a program that triggers a stable cell cycle arrest and can modify the tissue microenvironment through its effect on cell membrane and secretory proteins. Here we show that specific ablation of p53 in hepatic stellate cells, which undergo a process of proliferation and senescence in the fibrogenic response to liver damage, enhances liver cirrhosis, reduces survival and increases the malignant transformation of adjacent epithelial cells into hepatocellular carcinoma. This p53-dependent senescence program involves the release of secreted proteins which skew macrophages into a tumor-inhibiting M1-state that can eliminate senescent stellate cells. In contrast, p53-deficient stellate cells secrete factors that promote M2 polarization, which is pro-tumorigenic. Our study reveals that p53 can exert a non-cell-autonomous tumor suppressor response and suggests that this occurs, in part, by its ability to influence macrophage polarization. We used microarrays to detail the global programme of gene expression underlying p53-dependent senescent and identified distinct classes of up-regulated or down-regulated genes during this process. Proliferating and senescent stellate cell pellets were collected RNA extraction and hybridization on Affymetrix microarrays.
Project description:The p53 protein is a cell-autonomous tumor suppressor that restricts malignant transformation by triggering cell cycle exit or apoptosis. p53 also promotes cellular senescence, a program that triggers a stable cell cycle arrest and can modify the tissue microenvironment through its effect on cell membrane and secretory proteins. Here we show that specific ablation of p53 in hepatic stellate cells, which undergo a process of proliferation and senescence in the fibrogenic response to liver damage, enhances liver cirrhosis, reduces survival and increases the malignant transformation of adjacent epithelial cells into hepatocellular carcinoma. This p53-dependent senescence program involves the release of secreted proteins which skew macrophages into a tumor-inhibiting M1-state that can eliminate senescent stellate cells. In contrast, p53-deficient stellate cells secrete factors that promote M2 polarization, which is pro-tumorigenic. Our study reveals that p53 can exert a non-cell-autonomous tumor suppressor response and suggests that this occurs, in part, by its ability to influence macrophage polarization. We used microarrays to detail the global programme of gene expression underlying p53-dependent senescent and identified distinct classes of up-regulated or down-regulated genes during this process.
Project description:Gene expression of mouse hepatic stellate cells was characterized under the following conditions: Quiescent (isolated from normal mouse liver) and reverted (isolated from mouse liver treated with 4 injections of carbontetrachloride followed by 45 day rest period) Affymetrix Mouse 1.0ST gene expression measurements were used to characterize the transcriptomic basis in quiescent hepatic stellate cells, isolated from normal liver, and reverted hepatic stellate cells, isolated from liver treated with 4 injections of CCl4 followed by a 45 day rest period. Gene expression of mouse hepatic stellate cells was characterized under the following conditions: A. Quiescent control hepatic stellate cells (n=4). B. Reverted hepatic stellate cells (n=4).
Project description:Hepatic stellate cells are involved in the development of hepatic fibrosis. We here perform transcriptional profiling of hepatic stellate cells (HSCs) isolated from Western diet/high fructose-fed C57BL6/J mice, carbon tretrachloride (CCl4)-treated C57BL6/J mice, and of murine HSCs differentiated in vitro. Specifically, gene expression profiles are obtained from hepatic stellate cells isolated from C57BL6 mice fed a Western Diet supplemented with high fructose for 12, 16 or 24 weeks or normal chow. From hepatic stellate cells isolated from C57BL6 mice treated CCl4 for 1, 4 or 8 weeks or treated with vehicle. From hepatic stellate cells isolated from healthy C57BL6 mice and seeded on normal plastic cell culture dishes for 1, 4, 8, or 12 days. And from hepatic stellate cells isolated from healthy C57BL6 mice and seeded on normal plastic cell culture dishes for 6 days in the presence of 10uM U0126 or DMSO.