Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Proliferation of endocrine cells was found to occur during early, i.e., first 12 weeks, exocrine pancreatic carcinogenesis after 6 weekly treatments of Syrian hamsters with the pancreatic carcinogen N-nitrosobis(2-oxopropyl)amine (BOP). Cells containing insulin (Ins), glucagon (Glu), and somatostatin (Som) were noted in all stages of tumor development and were present in adenocarcinomas and in metastases to the liver. Some of the cancer cells were of amphicrine (hybrid) type, i.e., produced both mucin and endocrine substances. Measurement of these hormones revealed a significant decrease in plasma Ins during early stages of carcinogenesis with concomitant increase of Ins level in pancreatic juice at 12 weeks after 6 weekly BOP treatments. Plasma Glu and Som were not changed. The changes noted, particularly in relation to Ins, suggest that proliferation of endocrine cells in pancreatic carcinogenesis may be associated with alterations in hormone secretion.
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PMID:Alteration of pancreatic endocrine cell patterns and their secretion during pancreatic carcinogenesis in the hamster model. 257 21

int-2 is a proto-oncogene that is partially homologous to angiogenesis-inducing fibroblast growth factor and is believed to play a role in mouse mammary carcinogenesis. Recent evidence has suggested that this proto-oncogene may also play a role in human breast cancer. In the present study, we used Southern hybridization analysis to examine DNA from 79 primary and 11 recurrent human breast cancers for evidence of activation of int-2 through either gene rearrangement or amplification. A similar analysis was performed for two other proto-oncogenes, c-erbB-2 and c-myc, also suspected of playing a role in the development of human breast cancer. Proto-oncogene status was correlated with estrogen (ER) and progesterone (PR) receptor status, patient age, and lymph node (LN) status at the time of surgery. Gene rearrangement was not a frequent occurrence with any of the proto-oncogenes. However, amplification of int-2 occurred at a significantly higher frequency in recurrent breast cancers than in primary cancers and in patients with primary cancers who were less than or equal to 50 years of age versus greater than 50 years of age at surgery. Although amplification of all three proto-oncogenes occurred at a greater frequency in primary tumors from patients with lymph node metastases than from those without lymph node metastases, a significant difference was noted only in the case of c-myc amplification. These findings confirm and extend earlier results of studies of int-2, c-erbB-2 and c-myc amplification in human breast cancers and point to a role for int-2 activation in certain cases of recurrent breast malignant neoplasia.
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PMID:Amplification of the proto-oncogenes int-2, c-erb B-2 and c-myc in human breast cancer. 261 95

Recent studies have demonstrated that epidermal growth factor receptor (EGF-R) shows great homology with the v-erbB transforming protein and the amplified expression of EGF-R accompanies the malignant transformation of squamous epithelium of the uterine cervix. In this study, the tissue localization of EGF-R in the oncogenesis of uterine cervical cancer was examined by the avidin/biotin immunoperoxidase technique using anti-EGF-R monoclonal antibody. Normal squamous and columnar epithelium was almost negative for EGF-R. The positive rate of EGF-R increased in the precancerous lesions, whereas it decreased in invasive and metastatic cancer (mild dysplasia: 36%, moderate dysplasia: 57%, severe dysplasia: 77%, carcinoma in situ: 82%, microinvasive carcinoma: 80%, squamous cell carcinoma: 24%, glandular dysplasia: 67%, adenocarcinoma in situ: 75%, adenocarcinoma: 8%, adenosquamous carcinoma: 33%, metastatic carcinoma of the pelvic lymph node: 21%). The positive rate of dysplasia in follow up cases was high in the progressive group (regressive group: 0%, persistent group: 62%, progressive group: 80%). These results suggest that EGF-R may play an important role in the early stage of carcinogenesis of uterine cervical cancer, and it will be used as one of the markers in the prognosis of precancerous lesions of the uterine cervix.
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PMID:[Immunohistochemical studies on epidermal growth factor receptor in oncogenesis of uterine cervical cancer]. 268 40

Protein kinase C (PKC) is composed of a family of isozymes that transduce signals of certain hormones, growth factors, lectins, and neurotransmitters. This review addresses the role of PKC in the regulation of cellular proliferation and its disorders. PKC is directly activated in vivo by the second messenger diacylglycerol, a lipid produced by phospholipase C-catalyzed hydrolysis of phosphatidylinositol and polyphosphoinositides. Diacylglycerol activates PKC by reducing the enzyme's requirement for Ca2+. Phorbol ester tumor promoters and related agents potently activate PKC by a mechanism analogous to that of diacylglycerol, providing evidence that PKC activation is a critical event in tumor promotion. However, the role of PKC activation in tumor promotion is not entirely clear. For example, bryostatin is a potent PKC activator that antagonizes phorbol ester-mediated tumor promotion, and mezerein is a second-stage tumor promoter that potently activates PKC. In addition to studies concerned with tumor promotion, studies of oncogene action also indicate a role for PKC in carcinogenesis. A number of plasma membrane-associated oncogene products and related proteins are PKC substrates, and PKC activation leads to induction of the expression of oncogenes that code for nuclear proteins. PKC is implicated in human breast and colon carcinogenesis. Tumor-promoting bile acids activate PKC, and PKC expression studies in rat colonic epithelial cells and human breast cancer cells indicate a positive role for PKC in the proliferation of the cells. Altered expression of PKC in human colon and breast tumors indicates that PKC isozymes may be useful markers for these diseases.
Cancer Metastasis Rev 1989 Dec
PMID:Biology of the protein kinase C family. 269 70

Serum thyroxine was significantly higher in 59 patients with hepatocellular carcinoma than in normal subjects, patients with uncomplicated cirrhosis (48), or other primary tumours with or without hepatic metastases (50). Elevated thyroxine levels appeared attributable to high levels of thyroxine binding globulin which showed a positive linear correlation with serum thyroxine in all groups studied. Despite this hyperthyroxinaemia all patients appeared clinically euthyroid and, consistent with this, T3 was elevated in only one patient and the free thyroxine index was normal in all. Amongst a group of 25 cirrhotic patients who were followed-up for between 12 and 72 months, there was a striking dissociation between the TBG values of those destined to develop HCC and those who did not. In the former group TBG rose steadily with time whereas in the latter group levels remained stable, or, more often, fell. The rises in TBG occurred prior to any clinical signs of tumour development and may be one of the earliest serological changes to occur during carcinogenesis in the cirrhotic liver.
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PMID:Hyperthyroxinaemia in hepatocellular carcinoma: relation to thyroid binding globulin in the clinical and preclinical stages of the disease. 283 1

Transglutaminase activity and subcellular distribution have been examined in both normal and tumour tissue. Subcellular fractionation of rat liver demonstrated a bimodial distribution for transglutaminase between the particulate (approximately 40%) and cytosol (approximately 60%) fractions. Isolation of enriched plasma membrane fractions indicated the presence of membrane associated transglutaminase activity which co-distributed with that of 5'-nucleotidase and Na+/K+-ATPase. Induction of hepatocellular carcinomas in rats by treatment with either diethylnitrosamine or 6-p-dimethylaminophenylazobenzothiazole resulted in a reduction in transglutaminase activity which was accompanied by redistribution of the enzyme to the particulate fraction of the cell. The tumour bearing liver appeared to represent an intermediate stage between the hepatocellular carcinoma and control liver when assayed for content and distribution of transglutaminase activity. The transglutaminase activity of four transplantable rat sarcomas (P7, P8, MC3 and CC5) was found to be greatly reduced when compared with the normal tissues of rat liver, lung and spleen. A further reduction in this activity occurred in the primary growths of the sarcomas P7 and P8 following detection of metastases. Our data suggest that such changes in the distribution and content of transglutaminase may be a feature of tumour tissue and may be of value in both monitoring and investigating the carcinogenic process.
Carcinogenesis 1985 Mar
PMID:Alterations in the distribution and activity of transglutaminase during tumour growth and metastasis. 285 74

Chronic oral administration of lead acetate and/or N-nitrosodiethylamine to rats produces three different types of renal cell tumors composed of basophilic, chromophobic or oncocytic cells. The most frequent tumor, often visible macroscopically, is made up of basophilic cells and forms tubular, cystic, pseudo-papillary or solid structures; it may show considerable cellular atypia but does not metastasize or invade the surrounding parenchyma. Chromophobic and oncocytic tumors are rare and can only be detected with the microscope; they usually form cystic or solid structures. Basophilic and chromophobic tumors arise from specific segments of the proximal tubules, characteristic for each carcinogen: P2, P3C and P3M for lead acetate; P2 and P3C for N-nitrosodiethylamine. Karyomegalia in proximal tubule cells appears to be irrelevant in renal carcinogenesis. However, the appearance of basophilic and chromophobic cells in P2, P3C and P3M segments is considered to be an early change in tumor development. Oncocytic microadenomas originate from collecting ducts showing focal oncocytic transformation. Synergistic or inhibitory effects are not observed after chronic simultaneous administration of lead acetate and N-nitrosodiethylamine, although both carcinogens act in common on P2 and P3C proximal tubule segments.
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PMID:Rat renal carcinogenesis after chronic simultaneous exposure to lead acetate and N-nitrosodiethylamine. 289 Dec 21

Characteristics of malignant tumors, including anaerobic metabolism and metastases to lung, liver, bone and brain, may permit the enhanced survival of edited parts of the genome during periods of rapid environmental change. Carcinogenesis may be partially analogous to fossilization.
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PMID:Malignancy may contribute to rapid evolution. 292 50

Recent advances in cutaneous immunobiology have led to the realization that skin is an important and unique immunologic organ. Studies on the immunobiology of skin cancers induced by ultraviolet radiation indicate that immune mechanisms can play a crucial role in the development of cutaneous tumors. This paper summarizes the evidence linking skin and the immune system and discusses current hypotheses concerning the mechanisms by which UV radiation interferes with cutaneous immunity. The significance of these findings for cutaneous carcinogenesis is discussed.
Cancer Metastasis Rev 1986
PMID:Advances in the immunobiology of the skin. Implications for cutaneous malignancies. 295 Oct 33

Expression of the ras oncogene product p21 (ras p21) in benign and malignant human colonic tissues was studied using the monoclonal antibody RAP-5 and the avidin-biotin-peroxidase technique. Histologically normal colonic mucosa and hyperplastic mucosa adjacent to carcinomas (transitional mucosa) were found, in most cases, to be negative for reactivity with the antibody or showed weak staining of a few epithelial cells. Similar findings were observed in hyperplastic and juvenile polyps. Of the 145 adenomas studied, 47 (32.4%) showed detectable levels of ras p21 expression. RAP-5 immunohistochemical staining was significantly associated with the degree of epithelial dysplasia (P less than 0.01) and the size of adenoma (P less than 0.05), but not with the histological type. Fifty-four of 70 primary adenocarcinomas (77.1%) were reactive with RAP-5 and usually demonstrated a higher percentage of stained cells and more intense cytoplasmic staining than that observed in adenomas. Although metastases often displayed a similar or even higher levels of ras p21 expression compared with the primary carcinomas, in 10 cases one or more metastatic lesions showed lower levels of ras p21. These results suggest that enhanced ras p21 expression may, at times, occur in the early stages of human colon carcinogenesis but are probably not associated with metastatic tumour progression.
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PMID:ras p21 oncoprotein expression in human colonic neoplasia--an immunohistochemical study with monoclonal antibody RAP-5. 304 43


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