Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019163 (hepatitis B)
 38,309 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The human hepatoma cell line, PLC/PRF/5, which is persistently infected with hepatitis B virus (HBV), has integrated HBV-DNA, secretes HBV surface antigen (HBsAg), and does not grow readily in congenitally athymic (nu/nu) mice. The present investigation was undertaken to ascertain whether the low tumorigenicity of this cell line was governed by a host immune response and/or was related to expression of HBsAg. Subcutaneous injection of 4-5 X 10(6) cells into BALB/c nude mice produced localized encapsulated tumors with morphologic features of primary hepatocellular carcinoma in 25% of the animals within 29-40 d. No tumor growth was observed at lower cell inocula. In contrast, SK-HEP-1, an HBV-negative human hepatoma cell line, produced tumors at 1-5 X 10(6) cells inocula in 66% of the animals. Immunosuppression of mice with antilymphocyte serum (ALS) or irradiation increased tumor incidence in mice inoculated with 1 X 10(6) PLC/PRF/5 cells to almost 100% and produced local invasiveness. Immunosuppression also reduced the latency, i.e., time to tumor appearance, and increased mean tumor weight. These results suggest that tumorigenicity was limited by the host immune response. The nature of the response was delineated by treating nude mice challenged with tumor cells with sheep anti-mouse interferon globulin (anti-IFN). When 2 X 10(6) cells were injected, tumor growth occurred in 75% of anti-IFN-treated mice, whereas controls injected with the same number of cells, but not receiving anti-IFN, failed to develop tumors. The tumors in the anti-IFN-treated mice were highly invasive and the latency period until tumor appearance was reduced to 3-5 d. An inverse correlation was found between susceptibility of the hepatoma cells to natural killer (NK) activity in vitro and resistance to tumor growth in vivo. In vitro cytotoxicity for PLC/PRF/5 cells was eliminated by anti-NK 1.1 and complement, establishing the effector cell as an NK cell. NK cell activity 14 d after inoculation of mice with PLC/PRF/5 cells was augmented against PLC/PRF/5 target cells but not against SK-HEP-1 cells. Treatment of mice with ALS, irradiation, or anti-IFN abolished NK activity against PLC/PRF/5 cells. Co-cultivation of nude mouse spleen cells with PLC/PRF/5 but not with HBsAg or SK-HEP-1 cells induced secretion of murine IFNalpha. These results suggest that the IFN/NK cell system may play a role in limiting tumorigenicity and invasiveness of HBV-infected human hepatocellular carcinoma cells by a mechanism similar to that found for other cells persistently infected with viruses.
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PMID:Role in nude mice of interferon and natural killer cells in inhibiting the tumorigenicity of human hepatocellular carcinoma cells infected with hepatitis B virus. 619 49

The human hepatocellular carcinoma cell line PLC/PRF/5, which synthesizes and secretes hepatitis B surface antigen, was grown under optimal conditions in tissue culture, using Eagle's minimal essential medium supplemented with 10% fetal bovine serum and 10(-11) M triiodothyronine on collagen rafts. Injection s.c. of the PLC/PRF/5 cell line into athymic BALB/c nude mice resulted in the growth of a well-circumscribed, moderately differentiated hepatocellular carcinoma. The intervals until tumor appearance and tumor "take" rates were dependent on inoculum dose. Four to 5 x 10(6) cells induced tumor growth in 29% of 14 injected mice within 29 to 40 days, while 7 to 13 X 10(6) cells induced tumors in all 15 mice within 10 to 12 days after inoculation. Hepatitis B surface antigen was detected in the nude mouse serum and tumor tissue, and its concentration roughly correlated with tumor weight. A low level of antibody against hepatitis B surface antigen was detected in five tumor-bearing animals, as well as in one mouse which did not produce a tumor. Hepatitis B core antigen and its antibody and hepatitis B e antigen and its antibody were not detected in 26 mice, using immunohistochemical and radioimmunoassay methods. alpha-Fetoprotein, carcinoembryonic antigen, and alpha-antitrypsin were detected in nude mice tumors, using the peroxidase-antiperoxidase technique. Finally, hepatitis B virus DNA, identified in the nude mouse tumor by molecular hybridization techniques, was compared to PLC/PRF/5 cell line hepatitis B virus DNA.
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PMID:Tumorigenicity in nude mice of a human hepatoma cell line containing hepatitis B virus DNA. 626 Mar 36

The pathologic findings of 232 consecutive cases of hepatocellular carcinoma (HCC) autopsied during the past ten years at Kurume, Japan, were analyzed from the point of view of global epidemiology, in relation to clinical feature, and in regard to incidence, age, sex, etiologic factors, size of liver, changes in noncancer parenchyma, gross type of tumor, extrahepatic metastases, intravascular and intraductal growths, cancer cell histology, hepatitis B surface antigen (HBsAg) in hepatocytes and cancer cells, liver cell dysplasia, and frequency and clinicopathologic characteristics of minute HCC. Furthermore, postmortem hepatic arteriography and portography were done in 152 livers for comparison with gross anatomy and celiac angiograms. It was found that: (1) epidemiologically, HCC in Japan is distinct from that in the West that it is frequently encapsulated, livers are generally small because of frequent and advanced cirrhosis and small cancer, minute HCC, is not uncommon at autopsy, cirrhosis most commonly associated is the one with thin stroma and medium size nodules, and micronodular cirrhosis is very rare despite frequent alcohol abuse; (2) HCC is increasing in incidence; (3) HBsAg is frequently found in parenchyma; (4) liver cell dysplasia is indirectly related to HBsAg with no evidence for premalignancy; (5) the lung is the most frequent site of metastasis but peritoneal dissemination is unusual; (6) intraportal tumor growth is very common and the hepatic vein is less frequently affected; (7) growth in the major bile duct is frequently associated with intraportal growth and clinically presents as obstructive jaundice; and (8) tumor is supplied solely by arteries and celiac arteriograms are closely correlated with gross pathologic findings.
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PMID:Pathology of hepatocellular carcinoma in Japan. 232 Consecutive cases autopsied in ten years. 629 17

The discovery of alpha-fetoprotein and hepatitis B virus related antigens, and the development of diagnostic techniques in the past decade brought a new epoch in the study of hepatocellular carcinoma (HCC). Therefore, pathology of HCC should be re-investigated in accordance with the development of clinical aspects. In this paper, we have described the pathology of HCC based on both autopsy and surgical materials with special reference to angioarchitecture, unusual tumor growth, and histological growth pattern of HCC. Primary tumor, tumor thrombi in the portal vein and the hepatic vein, and intrahepatic metastasis receive arterial blood supply through arterial tumor vessels deriving from the hepatic artery. Unusual tumor growths, such as intrabile duct and intra-atrial tumor growths, have become relatively common, and tumor casts in the bile duct and the right atrium also receive arterial blood supply through arterial tumor vessels. histological growth pattern of HCC can be classified into three types; sinusoidal type, replacing type, and pseudoencapsulated type. The frequency of remote metastasis is different in each type.
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PMID:[Pathology of hepatocellular carcinoma]. 632 55

Woodchuck hepatocellular carcinoma has been successfully transplanted into nude (athymic) mice. The morphology of heterotransplanted tumor is similar to that of naturally occurring hepatocellular carcinoma before transplantation. The growth rate of transplanted tumor was very slow compared with those of other transplanted tumors. During the first month, only two tumors appeared. However, definitive tumor growth was noted in 6 of 20 nude mice about 3 months later. Seventeen of 20 nude mice exhibited sustained tumor growth after 6 months. The woodchuck hepatocellular carcinoma in nude mice provides an in vivo model for the study of oncogenesis of human hepatocellular carcinoma related to hepatitis B virus.
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PMID:Transplantation of woodchuck hepatocellular carcinoma in nude mice. 661 33

PLC/PRF/5 is a human liver cancer cell line which synthesizes hepatitis B virus surface antigen (HgsAB). These cells produced tumor in 6 of 8 (75%) congenitally athymic nude mice at 13 of 28 subcutaneous injection sites and in 13 of 14 (93%) mice inoculated intraperitoneally. Tumors were successfully transplanted to 4 of 6 additional nude mice. Tumor growth was rapid. Growth of cephalad tumors was significantly greater than for caudal tumors (0.39 mm/day versus 0.28 mm/day). Microscopic examination of tumors showed moderately well-differentiated hepatocellular carcinoma. Foci of identical cells were present in pulmonary veins in 7 of 14 tumor-bearing animals. Tumor cell karyotype was identical with that of PLC/PRF/5 cells. In addition, HBsAg was detectable in high titer in animals with extensive tumor. Biological features of PLC/PRF/5-induced tumors in nude mice appeared to closely resemble human hepatocellular carcinoma. Moreover, HBsAg may provide a marker of tumor growth.
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PMID:A human hepatoma cell line (PCL/PRF/5) produces lung metastases and secretes HBsAg in nude mice. 688 16

Hepatocellular carcinoma (HCC) accumulates a mutation of the p53 gene with a common substitution of nucleotide in a particular site. It is hypothesized that infection of hepatitis B virus (HBV) or exposure to aflatoxins could induce it. In Japan, the concentration of aflatoxins in the environment is low; however, infection of HBV and/or hepatitis C virus (HCV) is frequently seen in patients with HCC. The purpose of our studies was to determine whether these hepatoviral factors influence p53 alterations. In our results, p53 abnormalities, which were composed of loss of heterozygosity (LOH) and/or point mutation, were shown in 39% of patients. We postulated that they occurred at late stages in tumor growth based on the following two results. LOH analysis on p53 showed that most of the tumor nodule consisted of two phenotypes, LOH and non-LOH cancer cells. The p53 abnormalities correlated with the grade of cancer cell atypia which advanced with tumor growth. HBV and HCV infections were identified by polymerase chain reaction using DNA extracted from cancerous and noncancerous regions of the liver. By these methods, the patients who had been infected with either HBV or HCV showed an incidence of p53 abnormalities (45%) higher than those infected by neither (13%). However, the detection rate of these viruses was lower in the HCC region (33%) than that in the noncancerous region (56%) in cases with mutated p53. The low rate of HCV detection (22%) in the HCC region with altered p53 was attributable to these different viral detection rates. There was a difference in pattern of p53 mutational changes in patients depending upon whether they were infected by HBV or by HCV. Two of three HBV-infected patients had a transversional change of nucleotide at the G:C site to T:A. However, in cases with HCV, four of eight patients had a transitional change of nucleotide of p53. These results showed that HBV and HCV infections affect carcinogenic pathways causing p53 abnormalities independently.
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PMID:p53 gene abnormalities are closely related to hepatoviral infections and occur at a late stage of hepatocarcinogenesis. 826 44

To evaluate the applicability of recombinant adenoviral vectors in gene transfer to liver cancers, we infused the recombinant adenoviruses AD5CMV-LacZ and Ad5CMV-p53 through the portal veins into two lines of transgenic mice, one bearing the SV40 T antigen and the other the human hepatitis B viral envelope protein. These transgenic animals develop hepatocellular carcinomas (HCC) with predictable pathological manifestations. The levels of expression of the transgenes were dependent upon the viral doses. In all cases, high levels of expression were detected within 2 or 3 days after infusion, but were drastically reduced 7 days after infusion. Significant toxicities were found in the infused animals: > 80% of them died within 7 days after infusion with 10(10) pfu, and transgenic animals bearing HCC apparently were more sensitive to viral toxicity. Although a lower dose (10(9) pfu/animal) produced less toxicity, the levels of expression were substantially reduced (only about 10% of that in animals infused with 10(10) pfu). When Ad5CMV-p53 was infused into animals with nodular hyperplastic stage, the expression of the reporter gene seemed to distribute preferentially at the peripheries of the tumor nodules, and low levels of transgene expression were seen inside the nodules. In tumors in which necrotic lesions were evident, p53 was also expressed at the perpheries of the lesions. These distribution patterns were seen in both tumor models. There was no apparent suppression of tumor growth in the Ad5CMV-p53-infused animals. Our results suggest that alternative methods for gene therapy for HCC need to be explored.
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PMID:Adenoviral delivery of recombinant DNA into transgenic mice bearing hepatocellular carcinomas. 883 22

Hepatocellular carcinoma (HCC) frequently overexpresses the MDR1 gene and is resistant to drugs transported by the multidrug-resistance efflux pump. A xanthine analog, 1-(11-dodecylamino-10-hydroxyundecyl)-3,7-dimethylxanthine (CT-2584,CTI), is cytotoxic to many tumors in culture and was four times more effective than verapamil in inhibiting Rhodamine 123 secretion in MDR1-overexpressing Chinese hamster ovary cells. However, studies using PRF/PLC/5 (Alexander) cells revealed that CT-2584 is cytotoxic by another mechanism not involving inhibition of MDR1 function. Alexander cells have integrated the hepatitis B surface antigen (HBsAg) gene and quantitatively secrete HBsAg. The parent cell line, Alex 0, has low MDR1 expression and is drug-sensitive, whereas a derived line, Alex 0.5, is drug-resistant and overexpresses MDR1 100 times. Both cell lines were similarly killed within 24 or 48 hours by CT-2584. Freshly isolated rat and human hepatocytes were considerably more resistant to killing by CT-2584. In vivo, CT-2584 significantly reduced tumor growth in SCID mice bearing Alex 0 or 0.5 xenografts as determined by serial measurements of HBsAg. Hepatic parenchyma was normal, whereas apoptosis and cellular loss were observed in xenografts. The xenograft model is useful for testing pharmacological therapy of HCC.
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PMID:Effect of a xanthine analog on human hepatocellular carcinoma cells (Alexander) in culture and in xenografts in SCID mice. 936 62

It has been well demonstrated that interleukin-12 (IL-12) could be useful to defend against a variety of pathogens, to suppress tumor growth and metastasis, and even to be employed as an adjuvant of vaccines to enhance beneficial type 1 T helper (Th1) cell response over detrimental type 2 T helper (Th2) cell responses. To apply IL-12 genes in gene therapy such as a DNA vaccine, a pIL-12 vector was constructed that contained two cytomegalovirus (CMV) promoters to drive the expression of p35 and p40 subunits, respectively. In addition, a pscIL-12 vector was designed with a linker to fuse p35 cDNA with p40 cDNA to produce a single-chain IL-12 protein, ensuring not only that the expression of p35 and p40 subunits was equally expressed, but also that no free p40 subunits interfered with IL-12 activity. The data suggested pIL-12 could produce a rather high level of biologically active IL-12 after transfection of COS cell lines as well as C2C12 muscle cell lines, as measured by both concanavalin A blast proliferation assay and enzyme-linked immunosorbent assay. Interestingly, the pscIL-12 vector could also express a bioactive murine IL-12 fusion protein in vitro. Furthermore, in vivo functional studies also demonstrated that mice co-immunized with a pS vector expressing the major envelope protein of hepatitis B virus (HBV) and IL-12 vectors encoding native IL-12 or single-chain IL-12 fusion protein elicited higher levels of IgG2a anti-HBs antibody and of Th1-related cytokine. Because p35 and p40 genes can be expressed in a vector by using a single promoter, pscIL-12 should be useful in future applications for nucleic acid vaccination or for gene therapy against diseases.
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PMID:Construction of vectors expressing bioactive heterodimeric and single-chain murine interleukin-12 for gene therapy. 952 7


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