Cancer biochemistry biophysics最新文献_第8页

Effect of selenium on lipids and some lipid metabolising enzymes in DMBA induced mammary tumor rats. 硒对DMBA诱导乳腺肿瘤大鼠脂质及脂质代谢酶的影响。

Cancer biochemistry biophysics Pub Date : 1995-06-01

N Chidambaram, A Baradarajan

{"title":"Effect of selenium on lipids and some lipid metabolising enzymes in DMBA induced mammary tumor rats.","authors":"N Chidambaram, A Baradarajan","doi":"","DOIUrl":"","url":null,"abstract":"Current evidences clearly point out that an increase in lipid peroxidation influences lipid metabolism in cancer patients. Several investigations recognize selenium as a potent antioxidant, as well as an anticarcinogen, in both animal and human systems. Selenium was administered to Wistar rats bearing mammary tumor induced by 7,12-dimethylbenz(a)anthracene (DMBA) to study alterations in the concentration of lipid profiles and in the activities of some lipid metabolising enzymes. Control and tumor-bearing rats administered with selenium, were fed 5 mg sodium selenite/kg diet from the day of tumor induction. Plasma total lipids, total cholesterol, free fatty acids, triglycerides, phospholipids, VLDL and LDL cholesterol were significantly lower in selenium-treated rats bearing tumors, whereas, plasma ester cholesterol and HDL cholesterol were significantly greater due to selenium administration in DMBA induced-tumor rats. Total lipase and lecithin: cholesterol acyltransferase registered greater activities in plasma of selenium administered rats with tumor, while the activity of preheparin lipoprotein lipases in plasma of rats bearing tumors was lower due to selenium administration. These observations clearly indicate the effect of selenium in correcting the abnormalities of lipid metabolism in tumor-induced rats.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"15 1","pages":"41-7"},"PeriodicalIF":0.0,"publicationDate":"1995-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19516456","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Disposition of the plasmacytomagenic alkane pristane (2,6,10,14-tetramethylpentadecane) in mice. 浆细胞原烷(2,6,10,14-四甲基戊烷)在小鼠体内的分布。

Cancer biochemistry biophysics Pub Date : 1995-06-01

S Janz, E Shacter

引用次数: 0

Growth inhibitory action of brefeldin A with taxol and tiazofurin in human breast carcinoma cells. brefeldin A与紫杉醇和噻唑呋喃对人乳腺癌细胞生长的抑制作用。

Cancer biochemistry biophysics Pub Date : 1995-06-01

Y A Yeh, G Weber

{"title":"Growth inhibitory action of brefeldin A with taxol and tiazofurin in human breast carcinoma cells.","authors":"Y A Yeh, G Weber","doi":"","DOIUrl":"","url":null,"abstract":"Brefeldin A (NSC 89671), a macrocyclic lactone, blocks cellular protein transport by disturbing the association and dissociation of the Golgi apparatus with a 110-kD protein which is regulated by GTP. Brefeldin also induces retrograde transport from the Golgi membrane to the endoplasmic reticulum, which is mediated by microtubules which also require GTP for their biosynthesis. The anti-cancer action of taxol is exerted by enhancing tubulin polymerization in microtubule assembly; tiazofurin (2-beta-D-ribofuranosylthiazole-4-carboxamide, NSC 28693) acts through decreasing cellular GTP concentrations. Therefore, we tested the hypothesis that taxol (paclitaxel, NSC 125975) or tiazofurin might provide synergism with brefeldin. In human breast carcinoma MDA-MB-435 cells in the growth inhibition assays for brefeldin, taxol and tiazofurin, the IC50s were 41 nM, 6 nM and 13 microM, respectively. When brefeldin and taxol were given simultaneously, addition (brefeldin 10 nM with taxol 2 to 8 nM) or synergism (brefeldin 30 nM with taxol 2 to 8 nM) was observed. When brefeldin and tiazofurin were given simultaneously, or tiazofurin was followed 12 h later by brefeldin, addition was observed. The protocols yielding synergism and addition should be of value in the design of clinical trials for breast carcinoma.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"15 1","pages":"11-7"},"PeriodicalIF":0.0,"publicationDate":"1995-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19518672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Erythrocytes from Yoshida ascites sarcoma-bearing rats have reduced surface charge: the effect of tumor products. 吉田腹水肉瘤大鼠红细胞表面电荷减少:肿瘤产物的作用。

Cancer biochemistry biophysics Pub Date : 1995-06-01

V K Pestonjamasp, N G Mehta

引用次数: 0

Plasma fibronectin and sialic acid levels in various types of human brain tumors. 血浆纤维连接蛋白和唾液酸水平在不同类型的人类脑肿瘤。

Cancer biochemistry biophysics Pub Date : 1995-06-01

E Kökoğlu, S Süer, E Ozyurt, A Siyahhan, H Sönmez

引用次数: 0

Seventeenth Annual Interdisciplinary Cancer Research Workshop. 第十七届跨学科癌症研究研讨会。

Cancer biochemistry biophysics Pub Date : 1995-06-01

C Párkányi, P Politzer

引用次数: 0

Glycosyltransferase activities in human meningiomas. Preliminary results. 人脑膜瘤中糖基转移酶的活性。初步结果。

Cancer biochemistry biophysics Pub Date : 1995-06-01

R Gornati, S Basu, G Montorfano, B Berra

{"title":"Glycosyltransferase activities in human meningiomas. Preliminary results.","authors":"R Gornati, S Basu, G Montorfano, B Berra","doi":"","DOIUrl":"","url":null,"abstract":"The biosynthesis of a given glycosphingolipid is under the control of specific glycosyltransferases, while its catabolism is catalyzed by step-wise action of glycosidases. The net amount of glycolipids apparently result from the difference between these two processes. However, other parameters should be taken into consideration, such as intracellular recycling of catabolic products, membrane insertion, and membrane turnover. In order to establish a possible correlation between ganglioside expression in brain tumor and the activities of the enzymes involved in their metabolism, we analyzed the activities of specific sialyltransferases (SAT-1 and SAT-2), galactosyltransferase (GalT-4), N-acetylgalactosaminyltransferase (GalNAcT-1), and N-acetylglucosaminyltransferase (GlcNAcT-1) in 9 human meningiomas whose ganglioside pattern was characterized either by the predominance ganglioside GM3 (4 out of 9) or ganglioside GD3 (5 out of 9). The results indicated a strong correlation between the GM3/GD3 ratio and SAT-2 activity; to the contrary, SAT-1 activity did not show any correlation if compared with the Lc2/GM3 ratio. In all the samples where GM3 was the main ganglioside, little or no activity of GalNAcT-1 and GlcNAcT-1 was detectable.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"15 1","pages":"1-10"},"PeriodicalIF":0.0,"publicationDate":"1995-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"19518671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of virus-transformation and growth factor stimulation on isoprene biosynthesis in human fibroblasts: a correlation to cell growth. 病毒转化和生长因子刺激对人成纤维细胞异戊二烯生物合成的影响:与细胞生长的关系。

Cancer biochemistry biophysics Pub Date : 1995-01-01

O Larsson

{"title":"Effect of virus-transformation and growth factor stimulation on isoprene biosynthesis in human fibroblasts: a correlation to cell growth.","authors":"O Larsson","doi":"","DOIUrl":"","url":null,"abstract":"Serum depletion of exponentially growing normal human fibroblasts resulted in a moderate depression of the activity of HMG-CoA reductase which occurred simultaneously to the onset of growth arrest of the cells. Specific inhibition of HMG-CoA reductase using mevinolin also resulted in growth arrest. PDGF counteracted the suppressive effect of serum depletion on HMG-CoA reductase activity and cell growth. The growth inhibitory effect of serum depletion and mevinolin was correlated to a decreased biosynthesis of dolichols, in particular of dolichol-20. If PDGF was present in the serum-free medium a high rate of dolichol synthesis was maintained. This effect was mediated not only through an increased HMG-CoA reductase activity. PDGF also increased the incorporation of mevalonate into dolichols, once again into dolichol-20 in particular. In contrast to HDF, the growth of virus-transformed human fibroblasts was not decreased following serum depletion. This was correlated to a sustained activity of HMG-CoA reductase and a sustained dolichol-20 synthesis. In order to block growth and dolichol synthesis of the transformed fibroblasts a stronger inhibition of HMG-CoA reductase activity was required than in the normal cells. Conditioned medium isolated from the transformed cells was found to maintain a high growth rate and a high HMG-CoA reductase activity in serum-depleted HDF. In addition, the incorporation of mevalonate into dolichols was increased. The present data raise the possibility that PDGF or related factors, through autocrine loops, may contribute to the maintenance of a high dolichol synthesis in tumor cells.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"14 4","pages":"243-56"},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18768149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effect of tamoxifen on erythrocyte membrane lipids, lipid peroxides, and antioxidative enzymes in breast cancer women. 他莫昔芬对乳腺癌妇女红细胞膜脂质、脂质过氧化物和抗氧化酶的影响。

Cancer biochemistry biophysics Pub Date : 1995-01-01

M Thangaraju, R Ezhilarasi, P Sachdanandam

{"title":"Effect of tamoxifen on erythrocyte membrane lipids, lipid peroxides, and antioxidative enzymes in breast cancer women.","authors":"M Thangaraju, R Ezhilarasi, P Sachdanandam","doi":"","DOIUrl":"","url":null,"abstract":"Fasting blood samples were taken from 64 tamoxifen-treated postmenopausal women with early stage breast cancer. The levels of erythrocyte lipid peroxidation and the status of erythrocyte detoxifying enzymes were analyzed in untreated and treated patients for 3 months and 6 months with tamoxifen. Erythrocyte membrane lipid peroxidation and membrane cholesterol, phospholipid were also determined in all the patients. The 3 months and 6 months tamoxifen-treated patients showed significantly decreased levels of erythrocyte, erythrocyte membrane lipid peroxide with concomitantly increased levels of detoxifying enzymes when compared with baseline values of untreated women. Erythrocyte membrane cholesterol and phospholipid levels were markedly decreased in tamoxifen-treated patients than in untreated women. An interesting finding of this study indicates that the lipid peroxide, as well as, the lipid lowering efficacy of tamoxifen, was increased in patients with greater levels of baseline lipid and lipid peroxides in their erythrocyte membrane. These results indicate that tamoxifen is a potent suppressor of lipid peroxide formation through the favorable effects on membrane lipids and protective enzyme system.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"14 4","pages":"297-302"},"PeriodicalIF":0.0,"publicationDate":"1995-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"18769230","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Cysteine conjugate beta-lyase activity in human renal carcinomas. 半胱氨酸结合β -裂解酶在人肾癌中的活性。

Cancer biochemistry biophysics Pub Date : 1995-01-01

J A Nelson, B F Pan, D A Swanson, A A Elfarra

引用次数: 0