Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A recombinant retroviral vector was constructed which expressed antisense RNA of c-ets-2, c-myc and N-ras. The pseudotype virus was packaged and rescued by transfection in PA317 cells and used to infect human hepatoma cell line SMMC-7721. After selection with G418, resistant colonies were obtained. Stable integration of retrovirus in infectants was shown by Southern hybridization of genomic DNA and the presence of antisense RNA was detected by RNA dot blot hybridization. It was demonstrated that the antisense RNAs did inhibit the growth of human SMMC-7721 hepatoma cells. The ability to form colony in soft agar and tumorigenicity in nude mice of SMMC-7721 were significantly suppressed by the antisense RNAs. The result implicates the potential value in future cancer gene therapy.
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PMID:[Reversal of malignant phenotype of human hepatoma cells by antisense c-ets-2, c-myc and N-ras]. 780 49

We developed transgenic rabbits with a DNA construct containing the proto-oncogene c-myc conjugated to the Ig kappa-chain enhancer gene, E kappa. One of four transgenic rabbits was mated to a normal rabbit and we used the offspring to develop a colony of rabbits carrying the E kappa-myc transgene in their germline. Of a total of 19 E kappa-myc transgenic rabbits, eight developed tumors. The tumors were characterized histologically and four were diagnosed as lymphoma, and one each was diagnosed as embryonic carcinoma, hepatoma, ovarian carcinoma and basal cell carcinoma. By Southern analysis, we showed the four lymphomas were of B-lymphoid lineage and by nucleotide sequence analysis we found three of them most likely used VH1 in their VDJ gene rearrangements. Cells from the embryonic carcinoma, the hepatoma and two of the B-lymphomas were adapted to tissue culture. We discuss the possibility that tumors of non-lymphoid origin develop in the E kappa-myc transgenic rabbits because of the potential for NF-kappa B to activate the kappa-enhancer in cells other than B-lymphoid lineage cells.
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PMID:Lymphoid and non-lymphoid tumors in E kappa-myc transgenic rabbits. 780 3

Hepatocyte growth factor (HGF) stimulates growth of mature hepatocytes, whereas it inhibits growth of cancer cells including hepatocellular carcinoma (HCC) cells. However, the regulatory mechanisms for this phenomenon remains unclear. An important intermediary in HGF signal transduction in normal hepatocytes, c-myc, was not induced in FaO HCC cells after HGF stimulation, suggesting that intracellular signalling pathways of HGF in FaO HCC cells were different from those in normal hepatocytes. Protein kinase C (PKC) has been reported to be involved in signalling pathways of many growth factors. To study whether PKC is associated with this inhibitory mechanism, we studied the effects of HGF and/or 12-O-tetradecanoyl phorbol-13-acetate (TPA) on the growth of normal hepatocytes and FaO HCC cells. Consequently, HGF or TPA stimulated growth of normal hepatocytes, while equal doses of TPA or HGF inhibited growth of FaO HCC cells, respectively. In addition, TPA reversed the HGF effect in both normal hepatocytes and FaO HCC cells. These data suggest that an inhibitory effect of HGF on FaO HCC cells may be associated with changes of protein kinase C-mediated intracellular signalling pathways.
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PMID:Inhibitory effect of hepatocyte growth factor against FaO hepatocellular carcinoma cells may be associated with changes of intracellular signalling pathways mediated by protein kinase C. 782 2

We have established two cell lines of hepatocellular carcinoma [Hep-KANO, clone 1 (CL-1) and clone 2 (CL-2)] from tissue obtained at autopsy of a hepatitis B virus (HBV) carrier without histological signs of hepatitis or liver cirrhosis. These cell lines differed considerably from each other in morphology, proliferation pattern, alpha-fetoprotein secretion, albumin synthesis, cytokine secretion, modal chromosome number and transplantability to nude mice. Histologic examinations also revealed differences between them. Amplification of N-myc, L-myc, H-ras, K-ras, N-ras, c-erb-B and c-erb-B-2 and rearrangement of p53 were not found in either of the cell lines. However, CL-1 and CL-2 showed an identical HBV-DNA integration pattern. A 4-fold amplification of c-myc was observed in CL-1, but not in CL-2. Hep-KANO cell lines, CL-1 and CL-2 may be useful in clarifying the question of whether hepatocarcinogenesis is directly caused by HBV infection.
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PMID:Characteristics of human hepatocellular carcinoma cell lines (Hep-KANO) derived from a non-hepatitic, non-cirrhotic hepatitis B virus carrier. 782 95

Expression of oncogene mRNA was investigated in 37 cases of hepatocellular carcinoma (HCC) surgically resected using in situ hybridization (ISH) technique. C-myc, c-Ha-ras and N-ras DNA probes labeled with biotin were used. The hybrids were detected by streptavidin-biotin alkaline phosphatase staining. Thirteen cases of liver cirrhosis and 16 cases of non-cirrhotic liver were also examined as controls. In HCC cases, c-myc mRNA was expressed in 15 of 37 cases. The c-myc positive cells were found unevenly both in cancerous regions and in non-cancerous regions, being mainly distributed near the cancer capsule. The hybrids were detected mostly in cytoplasm of cancer cells. In some cases, they were seen not only in the parenchymal cells but also in the non-parenchymal cells, such as histiocytes, Kupffer cells and fibroblastic cells. In control cases, c-myc mRNA was expressed in five of 13 cases of liver cirrhosis and in three of 16 cases of non-cirrhotic liver. The expression of c-Ha-ras mRNA could be detected in only three of 37 cases of HCC. These three cases were early staged HCC. The expression of N-ras mRNA was detected in five of 32 cases examined of HCC. These five cases were differentiated type HCC. These results suggest that c-myc gene might play an important role in evolution and progression of HCC, and that ras genes might play a role in hepatocarcinogenesis at early stage.
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PMID:[Study on the expression of oncogene mRNA in hepatocellular carcinoma using in situ hybridization technique]. 783 Jul 8

Hepatocarcinogenesis is deterministic in transgenic mice expressing in the liver gene construct Alb-DS4 that encodes autocrine growth factor IgEGF (D Stern et al. (1987), Science 235: 321-324), causing their death within 7.1 months. Hepatic expression of construct AAT-myc encoding murine c-myc causes liver cancer in 44% of the mice at 14.8 months. Cooperation of these genes was evident in CD2F1 transgenics bearing Alb-DS4 plus AAT-myc, in which accelerated hepatocellular carcinoma (HCC) formation caused death of all mice within 4.4 months. Alb-DS4 also cooperates with the Hcs locus, which in C3H/HeJ mice mediates high susceptibility to spontaneous hepatocarcinogenesis, causing accelerated formation of HCC to which mice succumbed at 5.1 months. Thus, genes that predispose to HCC formation cooperate in transgenic mice and their interaction is a key to understand mechanisms that cause liver cancer.
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PMID:Autocrine mitogen IgEGF cooperates with c-myc or with the Hcs locus during hepatocarcinogenesis in transgenic mice. 786 54

The amino 3'-glycosyl phosphotransferase (neo) gene is the selectable marker most widely used in stable transfection or infection protocols. Because the neo gene product has phosphotransferase activity, it might modify the phosphorylation state when introduced in mammalian cells. NIH-3T3 fibroblast cells expressing the neo gene, after either infection with retroviral vectors or transfection with plasmids, showed a 50% reduction in both fructose 2,6-bisphosphate (Fru 2,6-P2) concentration and lactate production compared with control NIH-3T3 cells, indicating that these neo-expressing cells are less glycolytic. In addition, a marked decrease in the levels of mRNA for the procollagen 1 alpha and fibronectin genes was also observed in neo-expressing NIH-3T3 cells. This decrease was concomitant with an increase in the mRNA concentration of the endogenous c-myc gene. FTO-2B rat hepatoma cells also showed modifications in gene expression when the neo gene was introduced by stable transfection or infection. In these cells an increase in both P-enolpyruvate carboxykinase (PEPCK) and tyrosine aminotransferase (TAT) mRNA was observed. These results suggest that neo gene expression may induce changes in the cells, which should be considered when neo-selected cells are used to deliver specific genes in different therapy approaches and in embryo manipulation.
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PMID:Expression of the neomycin-resistance (neo) gene induces alterations in gene expression and metabolism. 791 94

The recently cloned protein, p21 (WAF1/CIP1) is a downstream effector of p53, and mediates growth arrest by inhibiting the action of G1 cyclin-dependent kinases. Since cellular differentiation is frequently characterized by G1 arrest, we examined whether p21 upregulation occurs in differentiation. We show that p21 expression is triggered by multiple differentiation-inducing agents in hematopoietic and hepatoma cells through a p53-independent pathway. The dramatic rise in p21 levels occurs as an immediate early response to differentiation inducers. The induction of p21 is coupled to the expression of early differentiation markers, and is uncoupled from apoptosis. Finally, evidence is presented that p21 expression is uncoupled from G1 arrest in the presence of deregulated c-myc.
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PMID:Induction of p21 (WAF-1/CIP1) during differentiation. 793 67

Oral vanadate administration has been demonstrated to normalize blood glucose levels in ob/ob and db/db mice and streptozotocin (STZ) diabetic rats. The exact mechanism of this vanadate effect is uncertain, since there are no consistent effects on the insulin receptor tyrosine kinase activity or phosphotyrosine phosphatase activity. We have therefore studied the postreceptor actions of vanadate, focusing our attention on the steady-state levels of mRNA of enzymes involved in carbohydrate metabolism. When compared with their lean (ob/+) controls, the livers of ob/ob mice exhibited an approximately 90% reduction in the levels of phosphoenolpyruvate carboxykinase (PEPCK) mRNA and twofold to fivefold higher levels of the mRNAs for glyceraldehyde-3-phosphate dehydrogenase (GAPDH), the "liver beta-cell" glucose transporter (GLUT2), and the proto-oncogene c-myc. Administration of sodium vanadate (0.25 mg/mL) in the drinking water of ob/ob mice over a 45-day period resulted in a near normalization of blood glucose and increased PEPCK mRNA levels more than ninefold. Starvation of the ob/ob mice for 24 to 48 hours also increased PEPCK mRNA levels by fourfold to 15-fold. Vanadate treatment did not alter mRNA levels of any other proteins studied and had no effect on PEPCK mRNA in ob/+ mice. However, 1 to 100 mumol/L vanadate produced a concentration-dependent increase in PEPCK mRNA levels in an H35 hepatoma cell line, an effect opposite to the suppression of PEPCK mRNA produced by insulin. In summary, hyperglycemia in the ob/ob mouse is characterized by decreased expression of PEPCK and increased expression of GAPDH mRNA.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Vanadate normalizes hyperglycemia and phosphoenolpyruvate carboxykinase mRNA levels in ob/ob mice. 796 88

We have created transgenic mice lines in which SV40 T and c-myc expression was controlled by the L-pyruvate kinase gene regulatory region which is responsible for hepatic and pancreatic expression specificity, and strong dependence of this expression upon the carbohydrate composition of the diet. Models of hepatoma and endocrine pancreatic tumors have been obtained. Both tumors were dependent upon the diet, since carbohydrates strongly increased frequency and precocity of both hepatic and pancreatic carcinomas.
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PMID:[The creation of diet-dependent cancer models using transgenesis in animals]. 797 51


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