Project description:Excessive fructose consumption causes fatty liver disease and steatohepatitis, conditions that elevate liver cancer risk. Although fructose was documented to cause metabolic abnormalities and microbial dysbiosis, whether and how it triggers liver tumorigenesis was unknown. We now describe a mouse model in which fructose acts as a carcinogen, giving rise to intestinal dysbiosis and translocation of inflammation-evoking microbial products that reach the liver via the portal circulation. These inflammatory stimuli initiate hepatocellular carcinogenesis. Genetic enhancement of epithelial barrier integrity and microbiota depletion with broad spectrum antibiotics prevent fructose-induced steatosis and liver cancer.
Project description:Using RNA-seq analysis, we study a DEN-induced HCC rat model during fibrosis progression and HCC development with special focus on liver inflammatory microenvironment. RNA-seq results show that DEN-induced liver tumors in rat model share remarkable molecular characteristics with human HCC, especially with HCC associated with high proliferation. In conclusion, our study provides detailed insight into the hepatocarcinogenesis in a commonly used model of HCC, facilitating the future use of this model for preclinical testing.
Project description:Autotaxin (ATX, Enpp2) is a secreted lysophospholipase D catalyzing the production of lysophosphatidic acid (LPA), a pleiotropic growth factor-like phospholipid. Upregulated ATX expression has been detected in various chronic inflammatory disorders and different types of cancer; among them increased ATX mRNA or immunohistochemical staining has been suggested in Hepatocellular carcinoma (HCC) patients. Conditional deletion of ATX/Enpp2 specifically from hepatocytes, in AlbEnpp2-/- mice, attenuated the DEN/CCl4-mediated HCC development in mice. To obtain mechanistic insights into the mode of action of the ATX/LPA axis in HCC development, we performed whole liver, genome wide expression profiling of DEN/CCl4-induced HCC upon the genetic deletion of Autotaxin (ATX) in AlbEnpp2-/- mice in comparison with DEN/CCl4-treated and untreated wt littermate mice.
Project description:Hepatocellular carcinoma is the third leading cause of cancer death worldwide, and it is necessary to elucidate the mechanism of hepatocarcinogenesis. Hepatocellular carcinoma (HCC) has a high mortality rate and develops based on the chronic inflammatory hepatic disease. Therefore, novel prophylactic or therapeutic strategies are required to improve outcome. In this study, influence of diethylnitrosamine (DEN) and retinoic acid (ATRA) on hepatocarcinogenesis was investigated in mouse. These results suggest that the control of NF-M-NM-:B signaling during the early stage of HCC development is important for the prevention of malignant transformation in hepatocytes. Genes induced by the following treatments in mice liver were investigated at 2 days or 7 days after treatment; DEN: diethylnitrosamine (treatment of DEN (drinking water 80 mg/L)) ATRA: retinoic acid (treatment of ATRA (drinking water 30 mg/L)) G0s2 siRNA : G0s2 knockdown mouse liver (treatment of G0s2 siRNA) Control siRNA: treatment of scramble siRNA (negative control)
Project description:The diethylnitrosamine HCC rat model (DEN-HCC) is a useful preclinical model mirroring human hepatocellular carcinoma. To overcome tumor heterogeneity of human HCCs linked to different etiologies and clonal selection, rat HCC samples were compared with matched non-tumor livers in order to identify HCC-related genes involved in the carcinogenetic process. Specifically, male Wistar rats received DEN (Sigma-Aldrich) in the drinking water (100 mg/L) for 8 weeks. Two weeks later the end of DEN treatment, animals were monitored by ultrasound imaging. Animals were euthanized 1 or 2 months after the end of DEN treatment, when the major diameter of at least one HCC nodule reached a dimension of 10 mm. Samples were collected for molecular biology and total RNA for microarray analysis was extracted by using Trizol. Two rat livers from untreated mice were included in the analysis.
Project description:Hepatocellular carcinoma is the third leading cause of cancer death worldwide, and it is necessary to elucidate the mechanism of hepatocarcinogenesis. Hepatocellular carcinoma (HCC) has a high mortality rate and develops based on the chronic inflammatory hepatic disease. Therefore, novel prophylactic or therapeutic strategies are required to improve outcome. In this study, influence of diethylnitrosamine (DEN) and retinoic acid (ATRA) on hepatocarcinogenesis was investigated in mouse. These results suggest that the control of NF-κB signaling during the early stage of HCC development is important for the prevention of malignant transformation in hepatocytes.
Project description:Single nucleotide polymorphisms in the FTO gene encoding a m6A demthylase are associated with obesity and cancer development. However, the functional role of FTO in the developemnt of progression of hepatocellular carcinoma (HCC) as a proteotypic obesity-associated cancer remains unclear. Here, we have generated mice with hepatic FTO deficiency (FTOL-KO) and subjected them to DEN induced HCC-development. FTOL-KO mice exhibit increased HCC burden. While control mice exhibit a dynamic regulation of FTO upon induction of liver damage, this response is abrogated in mice lacking FTO. Proteomic analyses revealed that liver damage-induced increases in FTO expression promotes m6A-demethylation of CUL4A reducing its protein expression. Functionally, knockdown of CUL4A restores the increased hepatocyte proliferation observed upon loss of FTO. Collectively, our study reveals a protective role for FTO-dependent dynamic m6A mRNA demethylation of CUL4A in the initiation of HCC development.
Project description:To better characterize the pathogenesis of hepatocarcinogenesis, we established mouse HCC model by diethylnitrosamine (DEN) exposures and performed whole genome expression profiling.
Project description:Transcriptional profiling by bulk RNA sequencing of murine livers or sorted immune cells, from DEN ALIOS NASH-HCC mouse model. Mice treated with CXCR2i (AZD5069) monotherapy, anti-PD1 monotherapy, or combination CXCR2i, anti-PD1 treatment. Published in doi: 10.1136/gutjnl-2021-326259
Project description:Gene-expression profiles of rat liver cirrhosis induced by diethylnitrosamine and the effect of erlotinib on liver fibrogenesis and liver cancer development Hepatocellular carcinoma (HCC) is the sixth most common solid tumor worldwide and the third leading cause of cancer-related death. Given the lack of successful treatment options, chemoprevention in high-risk patients has been proposed as an alternative strategy. Mounting evidence supports a role for epidermal growth factor (EGF) during chronic liver disease and hepatocellular transformation. We address the hypothesis that blocking the EGF-EGF receptor (EGFR) pathway may be an effective strategy for inhibiting fibrogenesis and hepatocarcinogenesis. A rat model of diethylnitrosamine (DEN)-induced cirrhosis was used to examine the effects of erlotinib on underlying chronic liver disease and HCC formation. The DEN-induced rat model closely resembles disease progression in humans both pathologically and molecularly. Erlotinib significantly prevented the development of HCC tumor nodules in a dose-dependent fashion. Further, erlotinib inhibited the activation of hepatic stellate cells and prevented fibrogenesis. Erlotinib also reduced hepatotoxicity and improved liver function. Finally, a gene expression signature predictive of poor survival in human cirrhosis patients was reversed in response to erlotinib. Our data demonstrate for the first time that EGFR inhibition prevents liver fibrogenesis. Further, our results suggest that erlotinib is a potentially effective HCC chemoprevention strategy through inhibition of cirrhosis progression which can be monitored at the molecular level. Keywords: Cirrhotic liver, Expression array, Illumina, Signatures, Outcome prediction Animals received humane care according to the criteria outlined in the M-bM-^@M-^\Guide for the Care and Use of Laboratory AnimalsM-bM-^@M-^] of the National Academy of Sciences. All animals were maintained in accordance with the institutional guidelines of the Massachusetts General Hospital Subcommittee on Research Animal Care. Male Wistar rats received weekly IP injections of diethylnitrosamine (DEN) at 50 mg/kg, 100mg/kg, or vehicle control (PBS) for 18 weeks. A subset of rats received either daily (5X a week) IP injections of 2 mg/kg erlotinib or vehicle control during weeks 13 - 18. In a separate study, the erlotinib dose was lowered to 0.5 mg/kg. The vehicle groups from the two studies were not significantly different so they were combined together for analysis. Rats were weighed at the end of each week. Animals were sacrificed at 9, 13 and 19 weeks after a one-week washout period to eliminate acute effects of DEN. At the time of sacrifice, the non-tumor liver tissues were collected in RNase-free tubes and snap-frozen in liquid nitrogen. Frozen tissues were stored at -80M-BM-0C until RNA extraction.