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)

Genomic DNA was extracted from archival pathology specimens comprising 10 squamous and 14 adenocarcinomas, including 7 with Barrett's epithelium adjacent to tumor, and corresponding normal esophagus from the resection margin. The polymerase chain reaction was used to amplify selected exons of p53 which were analyzed for mutations using single-strand conformation polymorphism analysis. Mutations were localized to exon 8 for 1 adenocarcinoma and to exon 5 for 1 squamous tumor and 4 of 7 Barrett's specimens. Sequencing confirmed mutations at codons 273 (CGT----CAT; adenocarcinoma) and 176 (TGC----TTC; squamous) and in Barrett's epithelium at codons 152 (CCG----CTG), 155 (ACC----GCC) and 175 (CGC----CAC). Specimens of Barrett's epithelium from separate sites had identical p53 mutations suggesting a clonal origin. Cancers arising in mutant epithelium did not have mutations corresponding to those found in the Barrett's specimens suggesting that other events are required for tumorigenesis.
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PMID:p53 gene mutations in Barrett's epithelium and esophageal cancer. 186 73

Two human ovarian tumor cell lines (SK-OV-3 and TR175), established from patients previously treated with alkylating agents, but not with cisplatin, expressed greater than 23-fold differences in cisplatin sensitivities in vitro. Cisplatin resistance in SK-OV-3 cells appeared to be associated with increased levels of glutathione and activities of glutathione reductase and glutathione peroxidase, with reduced catalase activity. No significant modification of drug uptake was noted and there was only marginally lower (16%) total platination of DNA, measured immunochemically, in these cells compared with the more sensitive TR175 cell line. SK-OV-3 cells, however, showed a significantly lower overall ability to remove drug-induced DNA damage, with an apparent inability to remove either the major DNA-DNA intrastrand cross-links in the sequence pGpG or the adducts cis-Pt(NH3)2d(GMP)2, although by alkaline elution repair of DNA-DNA interstrand cross-links was demonstrated. Significantly more of these interstrand cross-links were induced in these resistant cells. These data provide evidence for the involvement of altered glutathione metabolism and increased tolerance of certain types of drug-induced DNA damage as factors associated with the resistance phenotype of SK-OV-3 cells. Paradoxically, however, although the highly cisplatin-sensitive TR175 cells had lower glutathione levels this was not reflected in significantly higher total platination of DNA, and these cells appeared to be proficient in removing all the major platinum-DNA adducts quantitated in this study. Mechanisms responsible for this relative sensitivity to cisplatin remain to be identified.
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PMID:Anomalous relationship between cisplatin sensitivity and the formation and removal of platinum-DNA adducts in two human ovarian carcinoma cell lines in vitro. 187

The role of superoxide and lipid peroxidation for anti-tumor effect of intra-arterial injection with degradable starch microspheres (DSM) was investigated in rabbits. The anti-tumor effect of intra-arterial injection with DSM was studied in rabbits with VX2 carcinoma of the hind leg. The tumor growth in rabbit treated with DSM 5 times was completely suppressed, and thiobarbituric acid (TBA)-reactive substances in the tumor tissue treated with DSM were significantly increased. But the anti-tumor effect of DSM and the increase in TBA reactive substances in the tumor tissue treated with DSM were significantly inhibited by treatment with superoxide dismutase combined with catalase. These results suggest that the anti-tumor effect of intra-arterial injection with DSM may be due to ischemia-reperfusion injury and that active oxygen species and lipid peroxidation may play an important role in the anti-tumor effect of intra-arterial injection with DSM.
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PMID:[Role of oxygen species and lipid peroxidation for anti-tumor effect of intra-arterial injection with degradable starch microspheres]. 187 37

The authors reviewed 260 cases of bone tumors localized in the foot and treated at the Tumor Center of the Rizzoli Orthopaedic Institute: 191 were benign and 58 malignant and 11 metastasis. There was predilection for the hindfoot (57%), followed by the forefoot (33%) (prevalently the metatarsals). Localizations in the midfoot were rare (10%). Osteoid osteoma was observed in 26% of all of the tumors of the foot and in 35% of the benign forms. Among malignant neoplasms Ewing's sarcoma (27.5%) was the most frequent. Conservative surgery, which was always carried out in benign tumors, was also performed in some of the malignant ones, having an early diagnosis and a correct preoperative study. The indications and the limits of the different imaging techniques available are reported (bone scan, arteriography, CAT, MRI), and the role of biopsy in the definitive diagnosis of these neoplasms in discussed.
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PMID:Bone tumors of the foot: epidemiology and diagnosis. 189 86

Glucose oxidase (GO) catalyzes the conversion of beta-D-glucose and molecular oxygen to D-glucono-delta-lactone and H2O2. H2O2 produced by GO was effective in preventing tumor growth in mice bearing not only ascites tumor but also solid tumor. The effect of GO was enhanced by the combined administration of catalase inhibitors such as 3-aminotriazole, hydroxylamine and sodium azide or the GSH synthesis inhibitor buthionine-(S,R)-sulfoximine in vivo. The cytolytic activity of GO against T-24 cultured cells in vitro was also enhanced by addition of these inhibitors together with GO. In the peritoneal cavity of mice the antitumor effect of GO seemed to be dependent on the amount of oxygen released from oxygenated fluorocarbon-43 (FC-O2), an oxygen-supplying substance. Furthermore, the combined administration of H2O2-decomposing enzyme inhibitors and FC-O2 synergistically enhanced the antitumor effect of GO. These results suggest that GO is suitable for antitumor chemotherapy and that the use of inhibitors of H2O2-decomposing enzymes and FC-O2 potentiated the GO therapy.
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PMID:Enhancement of the antitumor effect of glucose oxidase by combined administration of hydrogen peroxide decomposition inhibitors together with an oxygenated fluorocarbon. 191 30

Tumor necrosis factor (TNF) activates polymorphonuclear neutrophils (PMN) to suppress tumor cell proliferation. This cytostatic activity could be blocked by the addition of red blood cells (RBC) into the assay. TNF-induced PMN cytostatic activity was mediated by hydrogen peroxide (H2O2). RBC have two major pathways to detoxify H2O2, one by catalase and the other by the glutathione redox cycle. Therefore, the catalase inhibitor 3-amino-1,2,4-triazole (AT) and the glutathione inhibitor N-ethylmaleimide (NE) were used to assess the role of each anti-oxidant in protecting the tumor target cells. RBC, depleted of catalase by AT, no longer protected Raji tumor cells from PMN cytostatic activity. However, depletion of reduced glutathione by NE had no effect on RBC protection of tumor target cells. Thus, RBC can protect tumor cells from cytostatic activity mediated by TNF-activated PMN, and the protection is a function of catalase, but not glutathione.
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PMID:Red cell regulation of tumor necrosis factor-induced human neutrophil cytostatic activity. 191 Oct 44

Forty-nine young males with advanced testicular cancer treated between March 1982 and June 1989 comprised a 49/588 (8%) subgroup with distant metastases to the retroperitoneum, mediastinum and lungs, and required mandatory surgery on basis of the risk for reactivation of "slumbering" malignant components in tumor tissue temporarily inactivated by chemotherapy and/or radiotherapy. Preoperative CAT-scan was carried out with the intention of mapping regional pathology related to the size, number, burden of the tumor tissue, and the occasional and prognostic ominous invasion of the great vessels. Regarding radical surgery, the positive predictive value of CAT-scan was found to be 33/34 (97%). The negative predictive value was 5/15 (33%) and was interpreted as an expression of the radiologist's cautious assessment. 14/49 (29%) died before March 1990. Poor prognosis was related to invasion of major vessels and was found in 14 patients of whom eight died. It seems established that CAT-scan presents an extremely valuable preoperative investigation when it comes to planning of surgical strategy in a patient population with testicular cancer metastases with difficult access.
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PMID:[Residual metastases from testicular cancer. CT as a diagnostic and strategic adjuvant]. 192 1

Twigs-dry leaves smoke condensate (TDS), as a source of clastogenic ROS and carcinogenic PAH, was investigated for its in vitro DNA-damaging effect in calf thymus DNA and human peripheral lymphocytes. An aqueous turmeric component--Aq.T--with an established antioxidant activity, was tested as a DNA protectant. TDS induced 13-fold damage to calf thymus DNA as judged by the emergence of a DNA damage specific, fluorescent product (em: 405 nm). Aq.T at 800 ng/microL extended 69% protection to calf thymus DNA and was comparable to the other protectants such as curcumin, BHA, vitamin E, SOD, and CAT. In human peripheral lymphocytes, TDS induced extensive DNA damage in comparison with the tumor promoter TPA, as judged by FADU. Aq.T at 300 ng/microL extended 90% protection to human lymphocyte DNA against TDS-induced damage, and was more effective than the other protectants--DABCO, D-mannitol, sodium benzoate, vitamin E (ROS quenchers), SOD, CAT (antioxidant enzymes), tannic acid, flufenamic acid, BHA, BHT, n-PG, curcumin and quercetin (antioxidants). Aq.T offered 65% protection to human lymphocyte DNA against TPA-induced damage and was comparable to SOD. The above results indicate that TDS induces substantial DNA damage in calf thymus DNA and human lymphocytes and Aq.T is an efficient protectant.
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PMID:DNA damage by smoke: protection by turmeric and other inhibitors of ROS. 193 45

A case of a tumor of the urinary tract discovered after renal trauma is reported. The clinical and radiolocal observations are presented as well as the interest of this case in forensic medicine. A review of the legal aspects recalls the principles of imputability in cases of cancer and trauma. While malignant tumors discovered after renal trauma are often renal cancers, urinary tract tumors can also be revealed after renal trauma. This unfrequent circumstance of discovery underlines the importance of control urography in cases of renal trauma, of history taking (smoking), and of the requirement for follow-up investigations if intra-luminal urographic abnormalities persist without damage to the renal parenchyma on the CAT scan.
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PMID:[Tumor of the urinary tract discovered after renal trauma. Medico-legal implications of a case]. 194 Apr 29

Although the pathogenesis of asbestos-induced pulmonary damage is still not completely understood, an important role has been attributed to active oxygen species. In the present paper we present results of a study investigating the effect of crocidolite asbestos inhalation on different lung antioxidant enzymes in rats. During the development of pulmonary fibrosis induced by crocidolite asbestos, lung superoxide dismutase, catalase and selenium-dependent glutathione peroxidase activities increased, indicating an adaptive response to increased pulmonary oxidant stress. However, this adaptive response obviously is not sufficient to protect the lung from asbestos-induced pulmonary damage. Considering the role of active oxygen species in both the fibrotic process and tumor promotion, it is hypothesized that antioxidants may also protect the lung from chronic asbestos-induced pulmonary damage such as bronchogenic carcinoma.
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PMID:Increases in endogenous antioxidant enzymes during asbestos inhalation in rats. 196 19


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