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)

Tyrosine aminotransferase (TAT) induction by glucagon and dexamethasone in the liver of tumor-bearing chickens was studied and compared with induction in healthy animals. The transplantable tumor was caused by inoculation of cells from a cell line induced by MC29 avian leukosis virus. TAT was hardly detectable in tumor tissue of control and dexamethasone-treated chickens, but it was induced by glucagon to levels which were significant although very low when compared to those in host liver or the liver of non-tumor-bearing controls after glucagon treatment. Dexamethasone failed to induce TAT in host liver at 8 A.M. while it significantly indiced TAT in the normal liver at the same time of the day. Similar failure of TAT induction was not detectable when glucagon was used instead of dexamethasone. Furthermore, it was found that diurnal variations in basal and dexamethasone or glucagon-induced TAT levels are considerably mitigated in host liver as compared to those observed in the liver of healthy animals. The possible reasons for these findings are discussed.
Int J Cancer 1975 Dec 15
PMID:Tyrosine aminotransferase induction in normal and tumor-bearing chickens. 0 Mar 37

The weakly acidic fraction (WAF) of cigarette smoke particulate matter was fractioned by silica get chromatography. We assayed the various primary subfractions for potential tumor-promoting activity by measuring the incorporation of tritiated thymidine into mouse epidermal DNA as induced by these subfractions. Based on these results and on chemical composition, the primary subfractions, were then combined into four major subfractions and tested on initiated mouse skin for tumor-promoting activity by long-term application. Two of these subfractions (40% of WAF) were inactive, whereas the other two (18 and 35% of WAF) showed tumor-promoting activity. The two active portions were then further chromatographed and tested by the short-term bioassay. Some major components of the resulting active fractions included alkyl-2-cyclopenten-2-ol-1-ones, catechols, hydroquinone, fatty acids, and 3-hydroxypyridines. Among these components, catechol, hydroquinone, 3-hydroxypyridine, 6-methyl-3-hydroxypyridine, linolenic acid, and linoleic acid were inactive as tumor promoters in the experimental animal. The activity of the alkyl-2-cyclopenten-2-ol-1-ones is unknown. Other components remain to be identified.
J Natl Cancer Inst 1975 Dec
PMID:A study of tobacco carcinogenesis. XIII. Tumor-promoting subfractions of the weakly acidic fraction. 0 47

Transplantable mammary adenocarcinomas and livers of C3H mice fed a stock diet or a linoleate rich diet (15% corn oil) contain similar amounts of oleate (ca 3 mg/gm tissue). On feeding either a high carbohydrate, fat free or a high carbohydrate, saturated fat-containing (15% hydrogenated coconut or cottonseed oil) diet for 6 weeks, oleate levels increased 2-fold in tumor and 5-fold in liver. The specific activity of stearoyl-CoA desaturase in liver microsomes was similar to that in the corresponding fractions of mammary glands of lactating mice. In liver, this activity was enhanced 2- to 3-fold by feeding a high carbohydrate, fat free or a high carbohydrate, saturated fat diet. The desaturase activity in mammary tumor microsomes, while only 10% of that in hepatic microsomes, remained unaltered regardless of the type of diet fed. These observations suggest that (a) a major portion of the oleate in the mammary tumor is not produced within the tissue, (b) dietary adaptation is not a general characteristic of stearoyl-CoA desaturase in neoplastic tissues, and (c) enhanced desaturase activity in liver is directly related to the absence of linoleate or oleate, or to a large decrease in oleate in the diet.
Lipids 1975 Dec
PMID:Stearoyl-CoA desaturase activity in mammary adenocarcinomas carried by C3H mice. 0 24

Adrenal-like lipoid-rich Leydig cells, which could be found in a cryptorchid testis, were investigated by light and electronmicroscopy. There were nodular and diffuse proliferation of these adrenal-like cells in the interstitium of the testis. Electronmicroscopically these cells are fasciculated and characterized by large liposomes, many tubulovesicular mitochondria, and a large smooth endoplasmatic reticulum. But the presence of crystals of Reinke in these cells underlined their relationship to Leydig cells. The clinical history of this case is characterised by an extreme adipositas (167 kg) and high urinary estrogenexcretion. This excretion could be suppressed with dexamethasone and stimulated with HCG. After orchiectomy estrogen excretion decreased for 4 months and then increased again, after ACTH stimulation performed by reason of adrenal insufficiency. At this time there is no evidence of adrenal tumor; in the contralateral, scrotal testis, spermiogenesis and Leydig cells are without pathologic changes as revealed by biopsy.
Virchows Arch B Cell Pathol 1975 Dec 19
PMID:[Adrenal-like Leydig cells (author's transl)]. 0 95

A highly sensitive technique for isoferritin detection using 125I-labeled monospecific anti-human liver ferritin antibody for the identification of isoferritins after the analysis of small quantities of ferritin by isoelectric focusing in polyacryl-amide gels was applied to the study of renal, pancreatic, and colonic carcinomas. In all tumors studied, the isoferritin composition differed from that of the corresponding normal tissue; major isoferritins with pl more basic than those of the normal tissues were consistently detected. Composition of purified ferritin from metastases closely resembled the isoferritin composition of the primary tumors. Examination of the serum isoferritin profiles of four patients with cancers did not reveal the presence of any tumor-specific changes in isoferritins. It is suggested that the abnormality in tissue ferritins in the three human cancers studied is the synthesis of major isoferritins in the more basic range, rather than the appearance of tumor-specific isoferritins in the more acidic range.
Cancer Res 1976 Dec
PMID:Isoferritin composition of tissues and serum in human cancers. 1 86

The synthesis of acetylcholine, as well as catecholamines, was studied by assaying the activities of choline acetyltransferase (ChA) and tyrosine hydroxylase (TH) in the tumor tissues and the culture cells of human neuroblastoma. In the majority of 20 neuroblastomas of sympathetic origin, both ChA and TH activities were detected at a significantly high level. In the culture cells of five cell lines of human neuroblastoma, ChA activity was high, but TH was negative in four of the lines. However, it was observed that these enzyme activities changed significantly while in the long-term culture. ChA assay is a useful diagnostic test for neuroblastomas that synthesize acetylcholine. Future studies of neuroblastoma should consider cholinergic activity.
J Pediatr Surg 1976 Dec
PMID:Acetylcholine synthesis in sympathetic human neuroblastoma. 1 56

Whereas glucocorticoids induce TAT, TRP, GPT in liver and only TAT in HTC cells, no hormonal effect on the synthesis of these enzymes was found in Zajdela hepatoma cells grown in vivo as an ascitic tumor, or in vitro as layer cultures. Although these cells remain uninducible, the hormone penetrates normally, but a strong decrease of the specific binding of cytosol and nuclear proteins with the hormone was observed. The impairment at the level of the hormone receptors could account for the non-inducibility of enzyme synthesis in ZHC cells.
Cell Differ 1976 Dec
PMID:Impairment of enzyme induction by glucocorticoids in Zajdela hepatoma cells. 1 35

The local graft-vs-host reaction (GVHR) test was used to assess the cellular immune competence of lymphocytes obtained from 29 patients with malignant tumors of the gastrointestinal tract before and after removal of the tumor. Prior to removal most patients showed impairment of cellular immune competence; 10 to 14 days after surgery there was an improvement in a considerable number of patients. However, when tested four months later, the GVHR was again negative in some patients. The possible factors leading to deficiency in cellular immune competence and the value of the local GVHR test in the long-term follow-up of patients who have had malignant disease are discussed.
Isr J Med Sci 1976 Dec
PMID:Cellular immune competence in patients with malignant tumors of the gastrointestinal tract. 1 89

Mechanically or enzymatically dissociated cells from three human medullary thyroid carcinomas (MTC) were grown in monolayer culture for periods up to seven months. Cultures of each tumor contained clusters of small epithelial-like cells which were readily identified by phase contrast microscopy. Immunocytochemical studies and electron microscopy showed that these cells contained abundant calcitonin and numerous secretory granules. Amine-storing mechanisms were also demonstrable in these cells by formaldehyde-induced fluorescence. Homogeneous cultures of epithelial-like cells showed no evidence of transitions into fibroblast-like cells. Addition of thyroxin to the tissue culture medium appeared to promote survival of epithelial-like cells in cultures of one tumor. The ability to morphologically recognize cultured cells with endocrine activity should facilitate establishment of human MTC lines for biochemical and physiological studies.
Cancer 1977 Dec
PMID:Medullary carcinoma of the human thyroid in monolayer culture: morphological and cytochemical correlations. 2 97

This report concerns a 49 year old asymptomatic male who had a mediastinal mass demonstrated on routine radiography. A large encapsulated tumour composed of small regular cells arranged in clumps and acini with fine vascular stroma was removed. The differential diagnosis on routine H&E section included parathyroid tumor, medullary carcinoma arising in ectopic thyroid tissue, epithelial thymoma or carcinoid tumor of the thymus. The presence of compressed thymic tissue around the tumor, and of argentaffin granules together with the electron microscopic appearance characteristic of the "enterochromaffin" or "APUD" group of cells allowed the diagnosis of carcinoid tumor of the thymus to be made. Electron microscopy showed that the cell cytoplasm contained electron dense membrane bound granules, together with bundles of microfilaments. Vesicles of smooth surfaced reticulum were present but rough surfaced reticulum was inconspicuous. No desmosomes were demonstrated. Special stains for amyloid and glycogen were negative.
Virchows Arch A Pathol Anat Histol 1977 Dec 29
PMID:Carcinoid tumour of the thymus. A case report including discussion of the morphological diagnosis and the cell of origin. 2 95


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