Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0596263 (carcinogenesis)
 64,820 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

(1) Passive hemagglutination and radioimmunoassay are suitable methods for the detection of AFP in the low concentration range. (2) In 3.72% of the cases a clinically unknown carcinoma was found in an unselected group of patients with liver cirrhosis. (3) 21.9% of the patients showed AFP elevations up to 2000 ng/ml. In 10.6% of this group, increasing titers demonstrated a primary liver cell carcinoma. In 89.4% a transitory rise of AFP was not associated with tumor growth. Levels return to normal values within three months in 90% of the cases. (4) Transitory AFP elevations are not correlated to clinical conditions (praecoma, coma, delirium, bleeding, ascites, shunt) or to biochemical parameters (GOT, GPT, bilirubin, prothrombin complex time, gamma-globulin). (5) A temporary rise in AFP is more frequently observed in groups with high hepatoma incidence than in groups with low hepatoma incidence. (6) Therefore, it may be suggested that a transitory rise of AFP could reflect a "primary reaction" of carcinogenesis. (7) Primary liver cell carcinoma is found to be more frequent in posthepatitic than in postalcoholic, cryptogenic, and other cirrhosis and to be more frequent in australia-antigen positive than in australia-antigen negative cases. (8) Routine serological tumor antigen screening of patients with a precancerous disease is useful.
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PMID:Early detection of hepatoma: prospective study in liver cirrhosis using passive hemagglutination and the radioimmunoassay. 5 21

A periodic acid-chromic acid-silver methenamine techniqe for visualizing glycoproteins at the electron microscope level was applied to colonic mucosa taken from areas adjacent to and remote from carcinoma. Normal control mucosa was obtained by biopsy of patients with no known gastrointestinal disease. Non-oxidized control sections were run in parallel. Quantitative and qualitative differences in glycoproteins were detected in the mucosa adjacent to carcinoma ('transitional' mucosa, as we call it) as compared with the normal. Furthermore, the vesicles in both the 'intermediate' and absorptive cells elaborate a glycoprotein product and it seems that a direct relationship exists between the increased vesiculation and the markedly developed 'fuzzy coat' in the 'transitional' mucosa. It is suggested that these findings may represent one of the features of an early stage of carcinogenesis. Histochemical and ultrastructural techniques of the kind used in this study may thus be of value in identifying or predicting malignancy in the colonic epithelium.
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PMID:An ultrastructural application of silver methenamine to the study of mucin changes in the colonic mucosa adjacent to and remote from carcinoma. 5 55

The human uterine cervix offers a unique opportunity to study the early lesions of squamous cell carcinoma, i.e., carcinoma in situ and dysplasia [combined as cervical intraepithelial neoplasia (CIN)]. In vivo, the patients with CIN have the epidemiological common denominators or "markers" of early onset of coitus, multiple sexual partners, 1st delivery before age 20, and antibodies to herpes simplex virus type 2 more frequently than do controls. The lesions themselves have specific epithelial and vascular changes observable with the colposcope in addition to the usual histological markers from biopsy specimens. The chromosomes and DNA content of cells in these lesions are abnormal. In vitro, the cells from CIN have characteristics somewhat between normal and invasive carcinoma. They lack contact inhibition and may be transferred for several generations, in contrast to normal cervical epithelial cells. The fibroblasts from areas adjacent to DIN are different from normal fibroblasts. The mitotic mechanism in cells cultured from CIN has a significantly prolonged prophase and telophase when compared to similar normal cells. The surface of CIN cells, unlike normal cells, has numerous microvilli when examined by scanning electron microscopy and has characteristic differences from normal cells with numerous elongated, irregular microvilli. With the transmission electron microscope, an increase in microvilli and a decrease in desmosomes and tonofibrils are seen in CIN cells. Some of these markers are being used clinically to manage patients with CIN. Other markers are the basis for further investigation of human carcinogenesis.
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PMID:In vivo and in vitro "markers" of human cervical intraepithelial neoplasia. 5 20

Young male and female albino rats ingested 0, 1, 5, 10 or 25 ppm Kepone, an organochlorine pesticide, in the diet for two years. Carcinomas of the liver, as well as hyperplastic nodules and moderate and severe diffuse hyperplasia were observed in Kepone-treated rats. Such hepatic lesions were not seen in control rats. Female rats ingesting Kepone were more susceptible than male rats to hepatic carcinogenesis. Rats ingesting 50 or 80 ppm Kepone developed severe diffuse hepatic hyperplasia and did not survive beyond 26 weeks.
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PMID:Carcinomas of the liver in rats ingesting kepone. 8 31

The expression of two markers of fetal liver, alpha-fetoprotein (AFP) and gamma-glutamyltranspeptidase (GGT), was studied in chemical and spontaneous hepatocarcinogenesis in mice. Serum AFP concentration increased within 3 weeks 3 weeks from the commencement of feeding of o-aminoazotuluene. This early elevation subsided about 3 months after the beginning of the administration of the carcinogen. A new, sustained elevation of the serum AFP level followed at 5 to 6 months accompanied by the appearance of liver tumors. In immunofluorescence, some small oval cells and scattered adult-type hepatocytes contained AFP during the early stage of chemical carcinogenesis. During the later phase, AFP was detected in a few of the nodular areas, in solitary hepatocytes, and in groups of carcinoma cells. GGT activity in the liver increased within 1 week after the carcinogen regimen was started, preceding the early increase of AFP production. At the final stage, the chemically induced hepatomas contained about 80 times more GGT than did normal liver. In histochemical staining, proliferating oval cells and small areas of hepatocytes stained for GGT during the early weeks, and later most nodules, small areas of nonnodular parenchyma, and carcinomas contained GGT. During spontaneous carcinogenesis in male C3HeB/FeJ mice, premalignant lesions, accompanied by a slight increase of serum AFP, precede the appearance of liver tumors. No cells staining for AFP were detected during this early stage. Once overt liver cancers had developed, AFP was readily detectable in the tumors and was localized to some but not all carcinoma cells. The corresponding serum AFP levels were highly elevated. In contrast to the high levels of GGT found during chemical carcinogenesis, no elevation of GGT was found in livers at various stages of spontaneous carcinogenesis, including cancers in eight individual mice. These results indicate that the production of AFP and GGT is not turned on as a single "genetic package," and that these two markers differ in their behaviour in liver carcinogenesis.
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PMID:Differential expression of alpha-fetoprotein and gamma-glutamyltranspeptidase in chemical and spontaneous hepatocarcinogenesis. 8 98

The present study was done to ascertain whether a specific carcinogenic agent has a causal effect on the initial proliferation of only one cell type or whether it acts indiscriminately on all cells in the breast secretory unit. Enzymes histochemistry and electron microscopy were performed on DMBA-induced mammary tumors in female Sprague-Dawley rats and on virus-associated spontaneous mammary tumors in C3H/HEJ mice. The results showed that the chemical carcinogen DMBA affects initial myoepithelial cell proliferation, while virus-associated mammary carcinoma originated from ductular epithelial cell proliferation. To determine whether a specific tumor is composed of a single cell type, tumors were grown in tissue culture. The monolayer was fixed in the usual manner for electron microscopy while in Falcon tissue culture plates. The plates were dissolved in xylene and the monolayer was cut into small pieces and embedded in the plastic media. Electron microscopy performed on the tissue culture and the original tissue from the virus-induced tumors showed the presence of viruses in large numbers. It also suggested the differentiation of basal membrane to form basal lamina and apical plasma membrane into microvilli. This study strongly suggests the presence of selective cell carcinogenesis in the mammary gland.
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PMID:A proposed selective cell carcinogenesis in mammary tumors. 10 7

The life history and histopathology of UV light-induced skin tumors were studied in NMR rats, outbred female Swiss mice, and Syrian golden hamsters. High intensity UV light of medium wavelengths produced hyperplasia and papillomas, as well as a dysplastic, intermediary solar keratosis-like stage, with distinct cellular atypia leading to several types of squamous cell carcinomas. High doses of UV irradiation of short duration caused scars, which developed into fibromas and fibrosarcomas composed of "light" and "dark" cells. Carcinomas with neoplastic squamous and fibrous components were uncommon; however, collision tumors with two components were occasionally seen. Angiomas and angiosarcomas with a proliferating endothelial structure were observed, but adnexal tumors, with follicular or sebaceous differentiation, and basal cell carcinomas were infrequent. Pigment cell tumors were found only rarely. The number of tumors and tumor-bearing animals at different stages of the experiment were also studied. Tumors were compared with lesions induced by chemical carcinogens in different systems. UV carcinogenesis was characterized by many tumor-bearing animals, but with a low total tumor count and a high mortality, thereby decreasing the number of animals-at-risk. The tumor types, their progression from on type to another, and the distribution of certain biologic characteristics were also analyzed. We concluded that UV irradiation is an effective tumor inducer in animal skin, and the type of tumor, its behavior, and location depend on the experimental conditions.
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PMID:Life history and histopathology of ultraviolet light-induced skin tumors. 11 77

The Growing importance of industrial noxae for carcinogenesis will, in the course of further progressive mechanization and industrialization, suggest an increasing confrontation with this problem. The above mentioned case, a patient working with insulating materials on industrial heating systems, impressevely demonstrates the transformation of chronic laryngitis into a carcinoma in the course of years, brought about by industrial influences and thus proving the exogenous origin of this genesis. Dust as well as strong effects of heat under conditions of variable atmospheric humidily are concerned to be principal damaging factors.
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PMID:[A case of industrial origin of laryngeal carcinoma (author's transl)]. 12 23

The purpose of this study was to find whether gastric resection enhances the incidence of carcinoma in the remaining part of the stomach. 66 male Wistar rats were subjected to stomach resection according to the Billroth I or the Billroth II method. These rats, as well as control animals with intact stomachs, were fed the carcinogen N-Methyl-N'-nitro-N-nitrosoguanidine (NG). -- 25 of 66 animals developed carcinomas in the gastric remnant. Precancerous lesions were seen in 18 rats. The tumours were characterized histologically as adenocarcinomas. They were almost exclusively localized in the region of the gastroenteral anastomosis. The process of tumour formation in the resected stomach was completed within 17-31 weeks on continuous administration of NG in a concentration of 120 mg/l in the drinking water. In contrast to these findings, the development of cancer in the intact stomach required on average 41 weeks under the same conditions of NG administration. However, with regard to the incidence of malignant changes, no significant difference was observed between animals undergoing the Billroth I method and those undergoing the Billroth II method.--The results suggest that the resected stomach of the rat is more susceptible to induction of cancer than the intac one. Exposure of the resected stomach to an oral carcinogen induces carcinogenesis predominantly in the anastomotic region.
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PMID:Susceptibility of the resected stomach to experimental carcinogenesis. 13 24

Until now, carcinoma of the large intestine resected previously for benign disease has not been published. However an increasing number of patients resected for Crohn's disease, diverticulitis or trauma may reach nowadays a high lifespan. On the other hand, it is known that the gastroenteral anastomosis is predisposed to cancer development. In this study, the question of whether the large intestine following colotomy or ileotransversostomy is sensitive to carcinogenesis is examined. Male Wistar rats, subjected to colotomy or resection and ileotransversostomy, were treated weekly by subcutaneous injection of 1,2-dimethylhydrazine (12 mg/kg body weight) for seven weeks. The animals were killed 54 weeks after the first injection. At autopsy, 21 out of 29 operated rats had developed adenocarcinomas of the remaining colon. Intact control animals had the same incidence of malignant degeneration of the large bowel. When the anastomosis is chronically irritated by inflammation or by formation of a diverticulum, development, of carcinoma near the stoma was observed. This was the case in three rats of 28 animals. The results demonstrate that the resected colon of the rat is not more sensitive to experimental carcinogenesis than the intact one.
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PMID:Experimental carcinogenesis in the resected colon of the rat. 14


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