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)

P-glycoprotein (P-gp) is thought to transport anti-cancer drugs and to be responsible for the multidrug-resistant (MDR) phenotype. Immunohistochemistry reveals that P-gp is also expressed in normal human tissues, such as the adrenal gland, kidney, liver, and the capillary endothelium of the brain and testis. However, little is known about the structural and functional variations of P-gp in these tissues. With immunoblotting and photoaffinity labeling, we found that the molecular mass of P-gp in these tissues varied between 130-140 kDa. To clarify the post-translational modification of P-gp, we studied the biosynthesis of P-gp in a human multidrug-resistant cell line (KB-C2). We found that P-gp was produced in KB-C2 cells as a 125 kDa precursor and was slowly processed (t1/2 = 45-60 min) to the mature form of 140 kDa. In the presence of tunicamycin, a 120 kDa form of P-gp was synthesized and this form was no longer processed. Treating the 125 kDa precursor form with endo-beta-N-acetylglucosaminidase H (Endo H) and the 140 kDa mature form with N-glycanase diminished the molecular size of P-gp to that of the tunicamycin-treated form. N-Glycanase almost completely removed [3H]glucosamine labeling from P-gp. These data indicate that the major modification of P-gp is N-linked glycosylation. P-gps from KB-C2 cells, kidney and adrenal gland had a different lectin-binding capacity. There seems to be a variety of N-linked glycosylations in tissue and tumor P-gps.
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PMID:Glycosylation of P-glycoprotein in a multidrug-resistant KB cell line, and in the human tissues. 167 8

We report that all-trans and 13-cis-retinoic acid as well as the synthetic compound CH-55 enhance tissue transglutaminase activity as they increase NIH-3T3 cell adhesiveness. The 4-hydroxyphenylretinamide (4-HPR) with low activity in inducing attachment, lectin binding and growth inhibition also fails to induce transglutaminase. Thyroxine (Thy), a compound with a response element common to RA, is inactive. The tumor promoter 12-tetradecanoyl-phorbol-13-acetate (TPA), which increases adhesiveness with different kinetics than RA, failed to enhance tranglutaminase. We conclude that retinoids with biological activity in inducing adhesion, inhibition of growth and increase of lectin binding, are also active in inducing transglutaminase activity.
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PMID:Retinoids induce tissue transglutaminase in NIH-3T3 cells. 167 38

Six granular cell tumors (GCT) of the neurohypophysis were studied by immunohistochemical techniques. They were all labeled by peanut lectin (Arachis hypogaea) and three showed reactivity for S-100 protein. Unlike extracranial GCT, neuron specific enolase (NSE), myelin basic protein (MBP) and vimentin were not detected in the tumor cells. Glial fibrillary acidic protein (GFAP), keratin and desmin were also not observed. On the other hand, some showed reactivity for alpha-1-antitrypsin (AAT), alpha-1-antichymotrypsin (AAC) and cathepsin B. These results suggest that neurohypophysial GCT have some features different from extracranial GCT and that they may not be derived from Schwann cells.
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PMID:Immunohistochemical study of granular cell tumors of the neurohypophysis. 168 58

Using Ulex europaeus I lectin (UEA1) to demonstrate endothelial cells, we have previously shown that frequency of capillary invasion correlates closely with maximum tumor thickness in primary cutaneous melanoma. UEA1 demonstrates both vascular and lymphatic capillaries; however, only vascular capillaries possess basement membranes. In order to ascertain whether these capillaries were lymphatic or vascular, we employed a double staining technique, using UEA1 in conjunction with a monoclonal anti-type IV collagen antibody. We studied 21 primary cutaneous melanomas. Seven of the 21 included lymphatic capillaries, while 14 did not. These lymphatic capillaries were very sparse and appeared to be residual dermal lymphatics rather than a result of lymphangiogenesis. Lymphatic permeation by melanoma was not seen in any of the tumors studied. There was no apparent association among tumor thickness, level of invasion, growth phase, necrosis, regression or mitotic index, and presence of lymphatics within the melanomas. Although scanty lymphatics are present in some primary cutaneous melanomas, this study does not suggest that lymphatic permeation plays a major role in the spread of melanoma to locoregional lymph nodes.
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PMID:Lymphatics in primary cutaneous melanoma. 169 Sep 53

Lectin histochemistry and electron microscopy were used to study a series of 13 solid or microacinar medullary carcinomas of the thyroid (MCTs) and compare them with four follicular MCTs and other forms of thyroid cancer. Lectin histochemistry was not found to be of diagnostic value, since the MCT did not display any distinct lectin-binding pattern. This approach demonstrated that all MCTs, irrespective of their histologic appearance, consist of polarized cells, arranged into microfollicles that can be demonstrated readily by electron microscopy. We conclude that all MCTs form follicles, some visible by light microscopy, while others are submicroscopic and apparent only on histochemical staining. Because of the histochemical and ultrastructural similarities between solid MCTs and tumors with a follicular pattern, the latter should not be considered a distinct variant of C-cell neoplasia.
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PMID:Lectin histochemistry and ultrastructure of medullary carcinoma of the thyroid gland. 169 Sep 76

The murine IgG2a monoclonal antibody (MoAb) 6-19 binds to the surface of human nonhematopoietic cells but not to hematopoietic cells. As previously described, it can be used with complement to selectively kill nonhematopoietic cells prior to culture of human bone marrow. It is now shown that the 6-19 MoAb recognizes a specific antigenic determinant of apparent molecular mass 80 kd, detected by western blotting on nonhematopoietic tumor cell lines, endothelial cells, and bone marrow stromal cells. Mouse L cells were transfected with human DNA, and the 6-19 monoclonal antibody selected cells that expressed an antigen with similar characteristics. The antigenic determinant is absent in hematopoietic tumor cell lines, peripheral blood cells, and bone marrow hematopoietic cells. Investigation of the biochemical nature of the antigen, using various enzymes, lectin-binding studies, and western blotting suggests that the 6-19 epitope is at least partially carbohydrate and that the protein has N-linked sugars but not O-linked. The affinity (Ka approximately 10(9) M-1) of MoAb 6-19 binding is similar in tumor cells and normal fibroblasts and endothelial cells. The identification of a specific antigenic determinant of 80 kd may help to discriminate between hematopoietic and nonhematopoietic cells in human bone marrow.
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PMID:An 80,000-kd glycoprotein cell surface antigen found only on nonhematopoietic cells in human bone marrow. 169 35

Serum alpha-fetoprotein from 146 patients with hepatocellular carcinoma, other malignancies, and benign liver diseases, was fractionated by lectin-affinity electrophoresis coupled with our sensitive detection method of antibody-affinity blotting. Compared with chronic hepatitis and liver cirrhosis, hepatocellular carcinoma was characterized by the increase in proportions of lentil lectin A-reactive alpha-fetoprotein-L3 and erythroagglutinating phytohemagglutinin-reactive alpha-fetoprotein-P4; the yolk sac tumor was characterized by the increase of concanavalin A-nonreactive alpha-fetoprotein-C1, lentil lectin-A-weakly reactive alpha-fetoprotein-L2, erythroagglutinating phytohemagglutinin-strongly reactive alpha-fetoprotein-P5, and Allomyrina dichotoma lectin-nonreactive, slow-migrating alpha-fetoprotein-Als; and gastrointestinal tumors were characterized by alpha-fetoprotein-C1, alpha-fetoprotein-L2, alpha-fetoprotein-L3, alpha-fetoprotein-P5 and Allomyrina dichotoma-nonreactive alpha-fetoprotein-A1. By combined evaluation of alpha-fetoprotein-L3 and alpha-fetoprotein-P4, hepatocellular carcinoma was discriminated from chronic hepatitis and liver cirrhosis with a sensitivity of 97% at a specificity of 99.7%. Because the alpha-fetoprotein level of the studied cases ranged from 60-1,500,000 ng/mL (60-1,500,000 micrograms/L), mostly greater than 200 ng/mL (200 micrograms/L), additional patients with lower levels of alpha-fetoprotein [16-177 ng/mL (16-177 micrograms/L) for 16 cases of hepatocellular carcinoma with liver cirrhosis and 28-185 ng/mL (28-185 micrograms/L) for 17 cases of liver cirrhosis alone] were analyzed for alpha-fetoprotein-L3 and alpha-fetoprotein-P4. The resulting sensitivity for combined evaluation was still as high as 88% at the same high specificity of 99.7%, indicating that the simultaneous analysis of alpha-fetoprotein-L3 and alpha-fetoprotein-P4 is effective in monitoring the evolution of hepatocellular carcinoma in cirrhotic patients.
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PMID:Lectin-reactive profiles of alpha-fetoprotein characterizing hepatocellular carcinoma and related conditions. 169 5

The sinusoids of 30 human hepatocellular carcinomas of various types were examined by electron microscopy and histochemically for binding to the Ulex europaeus lectin (UEA1). A population of sinusoidal macrophages was identified with an antibody to lysozyme (muramidase). The UEA1 binding was negative in normal sinusoids but positive in the tumor vessels. Macrophages resembling Kupffer cells were found within the tumor vessels but in smaller numbers than in either normal or cirrhotic liver tissue. Fibrolamellar and sclerosing carcinomas contained the smallest numbers. Ultrastructurally, endothelial cells of tumor vessels were thicker than normal, with fewer fenestrations. They contained bundles of microfilaments and showed basement membrane formation. Subendothelial myoid cells were found. These findings indicate that the sinusoidal vessels of hepatocellular carcinomas show features of true capillaries and precapillary blood vessels. The degree of this difference from normal hepatic sinusoids may reflect the relative immaturity of the cancer cells.
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PMID:An immunohistochemical and ultrastructural study of the sinusoids of hepatocellular carcinoma. 169 42

The gastric and intestinal phenotypic expressions of tumor cells in 18 adenomatous hyperplasias, 33 well-differentiated adenocarcinomas, and 16 undifferentiated adenocarcinomas (4 poorly differentiated adenocarcinomas, 10 signet-ring cell carcinomas and 2 mucinous adenocarcinomas) induced by N-methyl-N'-nitro-N-nitrosoguanidine or 4-nitroquinoline-1-oxide in the rat glandular stomach were studied by histochemical stainings for mucin and immunohistochemical staining for pepsinogen isozyme 1 (Pg 1). By histochemical staining for mucin [by the paradoxical concanavalin A method, the modified method with labeled peanut lectin, the galactose oxidase-Schiff (GOS) reaction, and the sialidase-GOS reaction] and immunohistochemical staining of Pg 1, gastric cancer cells of each histological group could be clearly classified into a gastric type, including mucous neck cell pyloric gland cell, and surface mucous cell subtypes, and an intestinal type, including goblet-cell, and intestinal absorptive cell subtypes. All tumors examined in this work consisted mainly of gastric-type cells but intestinal-type tumor cells were occasionally found among the gastric-type tumor cells. The incidences of intestinal-type cells in adenomatous hyperplasias (11.1%) and small well-differentiated adenocarcinomas (28.6%) were significantly less (P less than 0.05) than that in large well-differentiated adenocarcinomas (68.4%). The incidence of intestinal-type cells in small undifferentiated adenocarcinomas (25.0%) was also less than that in large ones (58.3%). The present results suggest the occurrence of change of phenotypic expression of tumor cells from the gastric type to the intestinal type during growth of tumors.
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PMID:Cellular differentiation and histogenesis of rat glandular stomach cancers. 169 50

For 52 patients with depressed adenomas of the stomach, histopathologic studies were done on 56 tumors and for 43 of them, histochemical and immunohistochemical features were examined. In addition, nondepressed adenomas (n = 57) and the depressed type of early gastric adenocarcinomas of the well-differentiated variety (n = 44) were studied as the controls. Depressed adenomas in the majority (73%) involved the entire thickness of the mucous membrane of the stomach with tubules of atypical epithelium, presenting a severe grade in many of the cases (41%). Paneth's cells were found in cases of a depressed adenoma, in significantly higher percentages (61%) than in those with a nondepressed adenoma (P less than 0.01). The frequency of cases with argyrophil cells was also higher in depressed adenoma (63%) than in nondepressed adenoma (36%) or in cases of early gastric carcinoma (32%). Carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9 were noticed in tumor cells, immunohistochemically in 28% of the cases with depressed adenoma, the frequency being intermediate between cases of a benign nondepressed adenoma (6% for both CEA and CA 19-9) and cases of early gastric carcinoma (71% for CEA and 66% for CA 19-9). No difference was noticed in lectin reactivity and mucin content between depressed and nondepressed adenomas, whereas tumor cells in the early depressed carcinoma had a higher lectin reactivity and less mucin content than those seen in the adenomas. It would thus appear that depressed adenoma is a benign neoplastic lesion; however, the malignant potential of this lesion is somewhat higher than the nondepressed counterpart, as indicated by the immunoreactivity to tumor markers and follow-up results reported by colleagues previously.
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PMID:Depressed adenoma of the stomach, revisited. Histologic, histochemical, and immunohistochemical profiles. 170 40


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