Cancer biochemistry biophysics最新文献_第5页

Effects of detergents on P-glycoprotein atpase activity: differences in perturbations of basal and verapamil-dependent activities. 洗涤剂对p -糖蛋白atp酶活性的影响:基础和维拉帕米依赖性活性扰动的差异。

Cancer biochemistry biophysics Pub Date : 1998-06-01

S Orlowski, M A Selosse, C Boudon, C Micoud, L M Mir, J Belehradek, M Garrigos

{"title":"Effects of detergents on P-glycoprotein atpase activity: differences in perturbations of basal and verapamil-dependent activities.","authors":"S Orlowski, M A Selosse, C Boudon, C Micoud, L M Mir, J Belehradek, M Garrigos","doi":"","DOIUrl":"","url":null,"abstract":"P-glycoprotein (P-gp), a plasma membrane glycoprotein associated with the multidrug resistance phenotype, is responsible for the ATP-dependent efflux of various amphiphilic drugs. Using membrane vesicles prepared from the multidrug resistant cell line DC-3F/ADX, we studied the perturbation of the basal (i.e. in the absence of drug) and verapamil-dependent P-gp ATPase activities induced by various detergents, at non-solubilizing, as well as at solubilizing, concentrations. The progressive membrane solubilization with increasing detergent concentration was monitored by light scattering and centrifugation experiments. For non-solubilizing detergent concentrations, all tested detergents except DOC induced a partial inhibition of P-gp ATPase activity, which was not correlated with the amount of the various tested detergents incorporated in the membranes. Analysis of the verapamil-induced P-gp activation reveals that P-gp ATPase activity is differently modulated by the various detergents at non-solubilizing concentrations. Thus, specific interactions between P-gp and detergents are more likely to occur rather than a global membrane perturbation. After solubilization by the various tested detergents, the basal P-gp ATPase activity was virtually completely inhibited, except in the presence of CHAPS which was able to preserve this activity at a level comparable to that measured in native membranes. However, the verapamil-induced P-gp ATPase activation was lost during P-gp solubilization by CHAPS, but recovered after dilution of CHAPS below its critical micellar concentration. These observations indicate specific interactions between P-gp and CHAPS molecules within the mixed micelles. On the whole, our data evidencing specific interactions P-gp/detergents are consistent with the location of the drug transport sites on P-gp transmembrane domains.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"16 1-2","pages":"85-110"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20828591","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

Plasma and erythrocyte total antioxidant status in patients with benign and malign breast disease. 良性和恶性乳腺疾病患者血浆和红细胞总抗氧化水平。

Cancer biochemistry biophysics Pub Date : 1998-06-01

L Afrasyap, G Güvenen, S Türkmen

引用次数: 0

Evolution towards hormone independence of the MXT mouse mammary tumor is associated with a gradual change in its estrogen receptor molecular polymorphism. MXT小鼠乳腺肿瘤向激素独立的进化与其雌激素受体分子多态性的逐渐改变有关。

Cancer biochemistry biophysics Pub Date : 1998-06-01

M J Piccart, S Trivedi, Y Maaroufi, A Debbaudt, S Veenstra, G Leclercq

{"title":"Evolution towards hormone independence of the MXT mouse mammary tumor is associated with a gradual change in its estrogen receptor molecular polymorphism.","authors":"M J Piccart, S Trivedi, Y Maaroufi, A Debbaudt, S Veenstra, G Leclercq","doi":"","DOIUrl":"","url":null,"abstract":"Using a method based on [3H]tamoxifenaziridine ([3H]TAZ) labeling, sequential immunoadsorption with anti-ER monoclonal antibodies, sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE) and fluorography, we observed a striking change inthe estrogen receptor (ER) electrophoresis pattern of the transplantable MXT mouse mammary tumor. Early, ER \"rich\" tumors (approximately 100 fmol/mg prot) displayed classical cytosolic 67 and 50 KDa bands. These bands disappeared in favor of a \"cytosolic\" 35 KDa band during progression towards undifferentiated ER \"poor\" tumors (approximately 25 fmol/mg prot). Although we can not rule out that this 35 KDa peptide results from in vivo ER proteolysis, it seems unique in view of the following: 1. It is immunoadsorbed not only by an anti-ER monoclonal antibody (H-222) directed to the hormone-binding domain, but also by an anti-ER monoclonal antibody (H-226) which interacts with an epitope in the A/B region close to the DNA-binding domain and is mainly exposed under activation conditions. 2. It does not bind [3H]estradiol([3H]E2) and a tentative to restore its [3H]E2 binding capacity with calmodulin and ATP was unsuccessful. The observation of similar approximately 35 KDa ERs in the nuclear fraction of early tumor transplants and in control uterus suggests that this peptide is already in an activated form. Structural alterations of ER and/or associated \"anchorage\" nuclear proteins may beat the origin of its cytosolic localization. Moreover, the fact that the addition of calmodulin and ATP to late MXT transplants cytosols fails to increase their [3H]E2 binding capacity indicates that the low ER content of these tumors does not result from a deficiency in the phosphorylation status of the receptor.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"16 1-2","pages":"169-82"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20829836","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 vitamin C on androgen independent prostate cancer cells (PC3 and Mat-Ly-Lu) in vitro: involvement of reactive oxygen species-effect on cell number, viability and DNA synthesis. 维生素C对体外雄激素非依赖性前列腺癌细胞(PC3和Mat-Ly-Lu)的影响:活性氧对细胞数量、活力和DNA合成的影响

Cancer biochemistry biophysics Pub Date : 1998-06-01

M Menon, C Maramag, R K Malhotra, L Seethalakshmi

{"title":"Effect of vitamin C on androgen independent prostate cancer cells (PC3 and Mat-Ly-Lu) in vitro: involvement of reactive oxygen species-effect on cell number, viability and DNA synthesis.","authors":"M Menon, C Maramag, R K Malhotra, L Seethalakshmi","doi":"","DOIUrl":"","url":null,"abstract":"Studies have described the protective role of vitamin C (ascorbic acid) in certain types of cancer. In this study, we report the effects of vitamin C treatment of two androgen independent prostate cancer cell lines from human (PC3) and rat (Mat-Ly-Lu or MLL) sources. In vitro treatment of PC3 and MLL with sodium ascorbate acid (0-10 mM) resulted in a decrease in cell viability and thymidine incorporation into DNA. These effects of vit. C were dose and time dependent. Ascorbate induced these changes through the production of hydrogen peroxide since addition of catalase (100-300 units/ml), an enzyme that degrades hydrogen peroxide, inhibited the effects of ascorbate on these cell lines. In contrast, superoxide dismutase, an enzyme that dismutates superoxide and generates hydrogen peroxide did not prevent ascorbate-induced changes emphasizing the involvement of reactive oxygen species (ROS) in cellular damage. That singlet oxygen scavengers such as sodium azide and hydroquinone, hydroxyl radical scavengers such as D-mannitol and DL-alpha-tocopherol did not counteract the effects of ascorbate on thymidine incorporation suggests that these free radicals are not involved in cellular damage. In conclusion, these results suggest that vitamin C inhibits tumor growth by virtue of producing reactive oxygen species. These results suggest that ascorbate is a potent anticancer agent for prostate cancer cells.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"16 1-2","pages":"17-30"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20830020","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

Biochemical characterization of in vivo alkylating agent resistance of a murine EMT-6 mammary carcinoma. Implication for systemic involvement in the resistance phenotype. 小鼠EMT-6乳腺癌体内烷基化剂耐药性的生化表征。对抗性表型的系统性参与的暗示。

Cancer biochemistry biophysics Pub Date : 1998-06-01

G Chen, B A Teicher, E Frei

{"title":"Biochemical characterization of in vivo alkylating agent resistance of a murine EMT-6 mammary carcinoma. Implication for systemic involvement in the resistance phenotype.","authors":"G Chen, B A Teicher, E Frei","doi":"","DOIUrl":"","url":null,"abstract":"While cancer drug resistance has been extensively studied in cell culture, little is known about more clinically relevant in vivo resistance. The in vivo resistance of a murine mammary carcinoma EMT-6 to alkylating agents was demonstrated in the present study to be associated with multiple biochemical changes. These included an up to 1.5-fold increase in activity of phase II drug metabolizing enzymes (DMEs), such as glutathione (GSH), glutathione reductase (GR), glutathione S-transferase (GST), glutathione peroxidase (GPX) and aldehyde dehydrogenase (ALDH), and an up to 88% decrease of phase I DME activity [7-ethoxycumarin O-deethylase (ECOD), P450 reductase (PR)] in the resistant tumors compared with the parental tumor. Transplant of either parental or resistant tumors to mice was accompanied by a decrease of both phase I and phase II DME activity in the livers of female Balb/C mice compared with the non-tumor mice. Moreover, at the protein level, while cytochrome P450 (CYP) IIB1/2 in the liver of mouse bearing both the sensitive and the resistant tumor was significantly diminished compared to that in the liver of non-tumor control mouse in Western analysis, there was actually an increase of this protein in the liver of the host bearing either of the two resistant tumors compared to that of the sensitive tumor-bearing animal. Although this in vivo resistance phenotype is not expressed in cell culture, the profile of most of the enzyme changes in the resistant tumors remained similar in in vitro culture of the isolated tumor cells. Collectively, these results demonstrate that this in vivo alkylating agent resistance is associated with multiple changes of both phase I and phase II DMEs in the resistant tumors, and some of these, such as CYP IIB1/2 protein are further altered in the resistant tumor-bearing mouse liver, suggesting a potential role of systemic factors in this resistance phenotype.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"16 1-2","pages":"139-55"},"PeriodicalIF":0.0,"publicationDate":"1998-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20829834","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

A short synthetic peptide (DTRPAP) induces anti-mucin (MUC-1) antibody, which is reactive with human ovarian and breast cancer cells. 短合成肽(DTRPAP)诱导抗粘蛋白(MUC-1)抗体，与人卵巢癌和乳腺癌细胞反应。

Cancer biochemistry biophysics Pub Date : 1998-06-01

D Avichezer, J Taylor-Papadimitriou, R Arnon

引用次数: 0

Cytotoxicity to tumors by alpha, beta-dihydric long-chain fatty alcohols isolated from esterolysates of uncytotoxic sheep cutaneous wax: the dependence on the molecular hydrophobicity balance of N- or iso-alkyl moiety bulkiness and two hydroxyl groups. 从无细胞毒性羊皮蜡酯水解物中分离的α、β -二氢长链脂肪醇对肿瘤的细胞毒性:依赖于N-或异烷基部分的体积和两个羟基的分子疏水性平衡。

Cancer biochemistry biophysics Pub Date : 1997-06-01

N Miwa, S Nakamura, N Nagao, S Naruse, Y Sato, K Kageyama

{"title":"Cytotoxicity to tumors by alpha, beta-dihydric long-chain fatty alcohols isolated from esterolysates of uncytotoxic sheep cutaneous wax: the dependence on the molecular hydrophobicity balance of N- or iso-alkyl moiety bulkiness and two hydroxyl groups.","authors":"N Miwa, S Nakamura, N Nagao, S Naruse, Y Sato, K Kageyama","doi":"","DOIUrl":"","url":null,"abstract":"Wool fatty alcohols (WF-Alc; C10-C33), separated by esterolysis of wool grease secreted from sheep sebaceous gland, inhibited growth of mouse Ehrlich ascites carcinoma (EAC) cells in contrast to no inhibition by unesterolysed wool grease. WF-Alc was fractionated by molecular distillation and subsequent octadecylsilica (ODS) gel liquid chromatography, showing that most of the growth-inhibitory activity was found in the most hydrophilic fraction with the lowest boiling-point (MW 200-300; C12-C20), ODS-HPLC of the fraction showed that most of the activity resided in two homogeneous fractions identified by GC-MS and 13C-/1H-NMR as alpha, beta-dihydric saturated fatty alcohols such as 1,2-hexadecanediol (n-C16(OH)2) and 16-methyl-1,2-heptadecanediol (iso-C18(OH)2), respectively. EAC cells implanted into mice were inhibited markedly by n-C16(OH)2 possessing a cytolysing ability and slightly by iso-C18(OH)2, but hardly by other alkyl-alpha, beta-diols (C12-C24) contained in WF-Alc. Thus, the antitumor activity of WF-Alc was exhibited only after saponification of uncytotoxic wool grease, showing necessity of unesterified hydroxyl groups, and was dependent upon the molecular hydrophobicity balance attributed to both hydroxyl groups and n- or iso-alkyl moiety bulkiness specified out of diverse species of fatty alcohols contained in WF-Alc.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"15 4","pages":"221-33"},"PeriodicalIF":0.0,"publicationDate":"1997-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20167901","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

RNA-RNA interaction and gene splicing. RNA-RNA相互作用和基因剪接。

Cancer biochemistry biophysics Pub Date : 1997-06-01

M Verma, R N Kurl, C Blass, E A Davidson

{"title":"RNA-RNA interaction and gene splicing.","authors":"M Verma, R N Kurl, C Blass, E A Davidson","doi":"","DOIUrl":"","url":null,"abstract":"The precise excision of intervening sequences during RNA splicing is an interesting example of the high degree of specificity involved in biosynthesis processes. Self-splicing RNA precursors achieve this specificity primarily through intramolecular interactions whereas all other types of RNA splicing requires interaction between cellular factors and specific recognition signals in the RNA precursor. About twelve years ago, the in vitro splicing system was developed and a general scheme of the pre-mRNA was proposed (Hernandez and Keller, 1983; Krainer et al., 1984; Lin et al., 1985; Padgett et al., 1984; Ruskin et al., 1984). A fundamental question in the splicing field is how the 5' and 3' splice sites are recognized and paired during the splicing reaction. Recent work in the splicing field has established that a network of RNA interactions may form the structural foundation of the spliceosomes. Possible solutions to many unsolved puzzles are getting attention. RNA-RNA interactions now appear to underlie many aspects of substrate recognition, reaction partner juxtaposition and catalysis. In this article we have presented the latest mechanisms involved in the pre-mRNA splicing and their implication in applied research including cancer.","PeriodicalId":9552,"journal":{"name":"Cancer biochemistry biophysics","volume":"15 4","pages":"211-20"},"PeriodicalIF":0.0,"publicationDate":"1997-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"20167900","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

Inhibition of the proliferation of Ehrlich ascites tumor cells by hydrostatic pressure. 静水压力对埃利希腹水肿瘤细胞增殖的抑制作用。

Cancer biochemistry biophysics Pub Date : 1997-06-01

T Yamaguchi, K Kuranoshita, M Fujii, Y Yokokawa, E Kimoto

引用次数: 0

Mitochondrial and cytosolic rhodanese from liver of DAB-treated mice. III. Inhibition kinetic studies. daba处理小鼠肝脏线粒体和细胞质罗丹斯。3抑制动力学研究。

Cancer biochemistry biophysics Pub Date : 1997-06-01

E Vazquez, S Gazzaniga, C Polo, A Batlle

引用次数: 0