Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

With the use of immunoperoxidase methods, paraffin-embedded hepatic tissue from 21 patients with primary hepatic carcinoma was tested for alpha-antitrypsin (AAT) deposition and was compared for sensitivity with the PAS reaction. Specific AAT immunoreactivity was present in tumor cells in half of the test cases, either alone or in combination with positive nonneoplastic hepatocytes. While the PAS findings generally parralleled the specific immunohistochemical studies, the latter technique exhibited greater sensitivity in AAT detection. Cytoplasmic tumor cell inclusions of three types were identified, but only one type, the solid, was found to represent immunoreactive AAT deposits. These findings confirm as association between hepatic deposition of AAT and the occurrence of primary liver carcinoma. Further prospective serum and tissue studies on patients with hepatoma are needed to extend these observations.
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PMID:Alpha-antitrypsin deposition in primary hepatic carcinomas. 5 64

This study was undertaken to investigate the possibility that Listeria monocytogenes, Brucella abortus, and Salmonella typhimurium share antigenic components with guinea pig line 10 hepatocarcinoma cells. Rabbits were immunized with sonicates of these bacteria or line 10 tumor cells. Other rabbits were immunized with line 1 cells, a tumor with antigenic characteristics different from those of line 10. The binding of antibodies to radiolabeled antigens prepared from extracts of bacteria and line 10 cells was studied by precipitation of radiolabeled antigen-antibody complexes with anti-rabbit immunoglobulin. Antibodies in sera from rabbits immunized with these bacteria and line 10 cells bound both the labeled bacteria and line 10 antigens. Antibodies in sera from rabbits immunized with line 1 cells did not bind the bacterial antigens. Inhibition studies involving reactions between radiolabeled Listeria and line 10 antigens and antibodies to Listeria and line 10 cells confirmed that the binding reactions were specific and that line 10 cells shared antigens with Listeria cells. The possibility that B. abortus and S. typhimurium also shared antigens with line 10 cells was suggested. Whether antigens shared by these bacteria and line 10 cells are identical with tumor-specific antigens was not determined.
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PMID:Shared antigens between bacteria and guinea pig line 10 hepatocarcinoma cells. 5 23

Tumour-specific antigen has been purified from the serum of animals bearing large progressively growing transplants of an aminoazo dye-induced hepatoma (D23). Antigenic activity was detected by the capacity of serum fractions to neutralize reactivity of antibody in hepatoma immune serum for cell surface expressed antigen on viable hepatoma cells as assessed by using the indirect membrane immunofluorescence test. Serum from animals bearing large i.p. grafts of tumour was fractionated by gel filtration on Sephadex G-150 columns at pH 7.3 and pH 2.8 to yield a crude antigen fraction which was further purified by affinity chromatography by using syngeneic rat hepatoma D23 immune IgG insolubilized on Sepharose 4B. The purified antigen exhibited a pI of approximately 4.6 on analytical gel isoelectric focusing. Molecular weight determination on Sephadex G-200 at pH 7.3 in nondenaturing buffer indicated a primary molecular weight of 55,000 and a small amount of aggregated material (mol. wt. greater than 250,000).
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PMID:Isolation and characterization of tumour-specific antigen from the serum of rats bearing transplanted aminoazo dye-induced hepatomas. 5 82

The expression of an "oncodevelopmental" protein, alpha-fetoprotein (AFP), has been systematically studied in rats during normal development and during regeneration of the liver by fetal rat hepatocytes in vitro, in rats bearing transplantable hepatomas, in rats fed chemical carcinogens, and in mice that spontaneously develop hematomas. AFP is a serum protein made normally during fetal and neonatal stages by liver and yolk sac cells. In newborn rats at approximately 4 weeks of age, the production of AFP is abruptly terminated, a process which is closely associated with cessation of liver cell proliferation. In adult rats, AFP production recurs following the reinitiation of hepatic DNA synthesis induced by partial hepatectomy or by the administration of heaptotoxic chemicals. Detailed metabolic and direct labeling studies of fetal rat hepatocytes in vitro also demonstrate a kinetically similar pattern of hepatocyte DNA synthesis and AFP production. In vitro studies utilizing combined autoradiography for DNA-synthesizing cells and immunofluorescence for AFP-containing cells demonstrates that replicating hepatocytes produce AFP, however, available data do not yet permit a distinction between G1 (pre- or postmitotic) and/or G2 production. During growth of an AFP- producing tumor, the serum concentration of AFP may be used as a accurate index of tumor growth, and, if a transplanted tumor is removed, as a marker for metastatic growth of the tumor. Using this model, we have shown that radiation to the lung at the time of surgical removal of a growing tumor in the leg will prevent establishment and growth of pulmonary metastases and that anti-AFP serum treatment may inhibit growth of a transplantable hepatoma that produces AFP. The exposure of rats to chemical hepatocarcinogens results in the appearance of evaluated serum AFP concentration as early as within 1 week of feeding; noncarcinogenic chemical analogs do not cause an elevation. AFP elevation also occurs with low doses of the hepatocarcinogen in the absence of detectable cell injury (by morphological examination of serum enzyme levels) or any other known morphological or biochemical change. This may represent a highly selective derepression of protein synthesis that occurs following the formation of a complex between the metabolites of the carcinogen and specific chromatin loci. Although every rat so far treated with even subcarcinogenic doses of hepatocarcinogens has elevated serum AFP concentrations, many primary carcinogen-induced hepatomas do not produce detectable AFP. Either there is a subsequent change in the preneoplastic AFP-producing cell that occurs prior to irreversible neoplastic alteration, or the hepatocytes originally influenced by the carcinogens to produce AFP are not necessarily the same cells that are the progenitors of the hepatoma produced by more prolonged exposure...
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PMID:Expression of an oncodevelopmental gene product (alpha-fetoprotein) during fetal development and adult oncogenesis. 6 4

In studies in this and other laboratories, induction of hepatocardinoma by several different chemical carcinogens was enhanced in rats fed diets deficient in lipotropes (choline, methionine, folic acid), amino acids, and niacin, and high in fat. In some cases, specific supplementation with lipotropes blocked carcinogenesis. In studies reported here, specific supplementation of a marginally deficient diet that enhanced carcinogenesis in rats, with the amino acids or lipotropes in which it was deficient, significantly decreased induction of hepatocarcinoma by N-nitrosodiethylamine. Niacin supplementation decreased hepatocarcinoma incidence only slight; the addition of beef fat to an adequate diet did not enhance tumor induction. Rats fed the amino acid- or lipotrope-supplemented diets had an increased incidence of hepatic hemangioendothelial sarcomas, compared to deficient rats or to rats fed the adequate control diet. Methionine was contained in both the amino acid and the lipotrope supplement and probably was responsible for reducing hepatocarcinoma incidence. Methionine has been found to have an anticarcinogenic effect in other studies and also to block the depletion of hepatic folate stores that is induced by N-nitrosodiethylamine. Interactions between carcinogens, S-adenosylmethionine, and folate may be significant in hepatic or other tissue carcinogenesis. One of more hepatic microsomal oxidases were depressed in rats fed any of the high-fat diets but were not correlated with tumor incidence.
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PMID:Reduction of N-nitrosodiethylamine carcinogenesis in rats by lipotrope or amino acid supplementation of a marginally deficient diet. 6 28

Three of 42 (7%) monkeys given aflatoxin B1 (AFB1) for longer than 2 years have developed primary malignant neoplasms of the liver. Liver biopsies performed at intervals during aflatoxin administration revealed that neoplasia was preceded by pathologic lesions of the liver, including toxic hepatitis, proliferation of pseudotubules, and hyperplastic nodules. Serum alpha-fetoprotein levels, monitored in one of the monkeys by radioimmunoassay, paralleled tumor growth and recurrence of the hepatocellular carcinoma. Normal serum alpha-fetoprotein levels were noted for a monkey with hemangioendothelial sarcoma. Our results implicate AFB1 as a liver carcinogen in monkeys and add additional support to the hypothesis that humans exposed to this substance may be at risk of developing liver cancer.
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PMID:Carcinogenicity of aflatoxin B1 in rhesus monkeys: two additional cases of primary liver cancer. 6 57

Germinal cell tumors of the testis were studied for the presence of several tumor-associated antigens. Antisera were produced by immunizing rabbits with the purified antigens of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), and hepatoma ferritin. Indirect immunofluorescence on embryonal carcinoma with or without teratoma components demonstrated that their staining range was 1--60 per cent with antiserum against AFP, 0--16 per cent with anti-serum against ferritin, and 0-40% with antiserum against CEA. Ferritin-like substances have not been described previously in germinal tumors of the testis. No staining was seen with seminoma cells or benign testicular tissues. Raised serum levels of AFP and the ferritin-like substance were related both to the presence of tumor and to dissemination of the disease. CEA occurred transiently in serum. Eleven patients with primary tumors had no antigen in their sera and have all survived, but the median survival time for 8 patients with either antigen in preoperative sera was 12 months. Five patients with advanced tumor in whom neither AFP nor ferritin was detected had a much longer median survival time (58 mo) than did 13 patients with high levels of serum AFP or ferritin (12 mo). The presence of either AFP or ferritin in sera of patients with primary or advanced disease, therefore, seemed to indicate a poor prognosis. The determination of both substances in serum may be useful in the follow-up of patients with certain types of testicular tumors. The proportion of cells containing each antigen varied in the different tumors. Similarly, each antigen could occur independently in serum. This suggested that certain germ cell tumors contained subpopulations of cells, which differed in their production and release of the antigens studied.
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PMID:Multiple antigens as marker substances in germinal tumors of the testis. 6 76

A 3 year old child with primary hepatocellular carcinoma and high AFP concentrations is described. Following hemihepatectomy, a sharp decrease and return to normal of serum AFP concentrations indicated the completeness of the surgical procedure. Repeat-normal serum AFP concentrations (less than 19 ng/ml), found during a three year follow-up, correlated well with the absence of clinical, laboratory and x-ray evidence of tumor recurrence. The differential diagnosis of abnormal AFP concentrations in childhood is discussed, and the importance of the AFP assay in the follow-up of post-hemihepatectomy patients for the assessment of the completeness of the surgical procedure, the prognosis, and the early detection of tumor recurrence is stressed.
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PMID:Serum alpha fetal protein in a three year old child with hepatoma. 6 12

Nineteen Zambian and 22 American patients with hepatocellular carcinoma were treated with Adriamycin every three weeks in intravenous doses ranging from 20-75 mg/m2 (depending upon their initial serum bilirubin levels). Four of 16 (25%) "good risk" Zambian and American patients who received 75 mg/m2 had objective responses, while in five additional patients there was evidence of either transient tumor regression or disease stabilization. In contrast three of 25 "poor risk" patients who received 20-60 mg/m2 had objective responses. Even in this latter group, however, transient, objective signs of tumor regression were noted in four patients. The results of the present study confirm previous reports suggesting anti-tumor activity for high doses of Adriamycin in hepatocellular carcinoma. Since those responses seen were generally incomplete and transient, further clinical trials of this agent used in combination or sequentially with other agents are indicated.
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PMID:A phase II study of adriamycin (NSC 123127) in patients with hepatocellular carcinoma from Zambia and the United States. 6 74

A serum B12-binding protein with increased sialic acid content (termed hepatoma B12-binding protein) that causes elevations of serum B12 and unsaturated B12-binding capacity has been found in some patients with hepatocellular carcinoma (hepatoma). We now report another patient with hepatoma with initial near-normal, unsaturated B12-binding capacity that increased 400-fold as the disease progressed and then fell 50% with response to chemotherapy. A perfusate of the tumor in the liver had 5 times more B12-binding protein than did the serum and was immunologically the same as the serum hepatoma B12-binding protein isolated from previous cases. A cell line derived from hepatoma produced significant amounts of B12-binding protein similar to hepatoma B12-binding protein, whereas cell lines from normal liver and other neoplasia did not. The hepatoma sera, perfusate, and media from the hepatoma cell line contained elevated sialyltransferase activity. These data suggest that some hepatomas produce increased hypersialylated B12-binding protein that is cleared slowly from the plasma and accumulates there as hepatoma B12-binding protein.
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PMID:The clinical and physiological implications of hepatoma B12-binding proteins. 6 88


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