Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0006142 (breast cancer)
160,383 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Enantiomerically pure 1, 2-diamino-1-(4-fluorophenyl)butanes were synthesized by stereoselective procedures. The enantiomeric purity was determined by (1)H NMR spectroscopy after derivatization with (1R)-myrtenal. For the coordination to platinum, the diamines were reacted with K(2)PtI(4). Reaction with Ag(2)SO(4) yielded the respective sulfatoplatinum(II) complexes, which were converted into the dichloroplatinum(II) complexes by treatment with 2 N HCl. The influence of the configuration and the kind of leaving group on the antitumor activity was studied on the MCF-7 and MDA-MB 231 breast cancer cell lines, as well as on the LnCaP/FGC prostate cancer cell line. It was demonstrated that the dichloroplatinum(II) complexes were more active than the respective diiodoplatinum(II) derivatives. Conversion into the sulfatoplatinum(II) complexes further enhanced the antiproliferative effects. The configuration determined the antitumor effects, dependent on the cell line used: MCF-7: (R, R) > (S, S) > (R, S) > (S, R); MDA-MB 231: (S, S) > (R, R) > (R, S) = (S, R); LnCaP/FGC: (S, S) > (R, R) > (R, S) > (S, R).
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PMID:Enantiomerically pure [1, 2-diamino-1-(4-fluorophenyl)butane]platinum(II) complexes: synthesis and antitumor activity against MCF-7 and MDA-MB 231 breast cancer and LnCaP/FGC prostate cancer cell lines. 1559 99

Nomegestrol acetate (NOMAC), a 17alpha-hydroxy-nor-progesterone derivative (17alpha-acetoxy-6-methyl-19-nor-4,6-pregnadiene-3,20-dione, the active substance in Lutenyl), is a potent and useful clinical synthetic progestin for the treatment of menopausal complaints and is under current development for oral contraception. Previous studies in this laboratory demonstrated that NOMAC can block sulfatase and 17beta-hydroxysteroid dehydrogenase, the enzymes involved in the biosynthesis and transformation of estradiol (E2) in hormone-dependent MCF-7 and T-47D breast cancer cells. In the present study, the effect of NOMAC on sulfatase activity using total breast cancer tissue, compared to the effect in normal breast tissue, was explored. Slices of tumoral or normal breast tissues (45-65 mg) were incubated in buffer (20 mM Tris-HCl, pH 7.2) with physiological concentrations of [3H]-estrone sulfate (5x10(-9) M), alone or in the presence of nomegestrol acetate (5x10(-5) - 5x10(-7) - 5x10(-9) M), for 4 h at 37 degrees C. Estrone sulfate (E1S), estrone (E1) and E2 were characterized by thin layer chromatography and quantified using the corresponding standard. It was observed that [3H]- E1S was only converted to [3H]- E1 and not to [3H]- E2, in normal or cancerous breast tissues, which suggests a low or no 17beta-HSD activity under these experimental conditions. The sulfatase activity was more intense with breast cancer tissue than normal tissue, since the concentrations of E1 were 42.5 +/- 3.4 and 27.2 +/- 2.5 pg/mg tissue, respectively. NOMAC, at the concentration of 5x10(-5) M, inhibited this conversion by 49.2% and 40.8% in cancerous and normal breast tissues, respectively. The sulfatase inhibition at low concentration (5x10(-7) M) was 32.5% and 22.8%, respectively. It is concluded that sulfatase activity is almost twice as potent in cancerous breast tissues than in normal tissues. Nomegestrol acetate is a strong anti-sulfatase agent, in particular with cancerous breast tissues. The inhibition of estrone sulfatase activity by NOMAC in total normal or cancerous breast tissues can open attractive perspectives for future clinical trials.
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PMID:Control of sulfatase activity by nomegestrol acetate in normal and cancerous human breast tissues. 1608 May 33

Hormone-sensitive tumours are among the most common cancers in women. Specific inhibition of the estrogen receptor by selective estrogen receptor downregulators or selective estrogen receptor modulators (SERMs) is effective for the treatment of breast and endometrial cancers and may be used for the prevention of breast cancer. Due to differential recruitment of co-activators and corepressors, SERMs are tissue specific and may have antiestrogenic effects in some tissues, with estrogen agonist activity in others. The ideal SERM would have antiestrogenic effects on the breast and endometrium, but pro-estrogenic effects on bone and lipids. The SERM, arzoxifene (LY-353381.HCl) meets all of these criteria. This review summarises the development, preclinical studies and the clinical outcome of arzoxifene and places it in context with other modalities in the treatment of hormone receptor-positive tumours.
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PMID:Arzoxifene: the development and clinical outcome of an ideal SERM. 1650 67

Epidermal growth factor (EGF)-conjugated copolymer micelles were prepared from a mixture of diblock copolymers of methoxy poly(ethylene glycol)-block-poly(delta-valerolactone) (MePEG-b-PVL) and EGF-PEG-b-PVL for targeted delivery to EGF receptor (EGFR)-overexpressing cancers. The block copolymers and functionalized block copolymers were synthesized using PEG as the macroinitiator and HCl-diethyl ether as the catalyst. The MePEG-b-PVL and the carboxyl-terminated PEG-b-PVL (HOOC-PEG-b-PVL) copolymers were found to have molecular weights of 5940 and 5900, respectively, as determined by gel permeation chromatography (GPC) analyses. The HOOC-PEG-b-PVL copolymers were then activated by N-hydroxysuccinimide and subsequently reacted with EGF to form the EGF-PEG-b-PVL copolymers. The efficiency for the conjugation of EGF to the copolymer was found to be 60.9%. A hydrophobic fluorescent probe, CM-DiI, was loaded into both the nontargeted MePEG-b-PVL micelles and the targeted EGF-conjugated PEG-b-PVL micelles. The effective mean diameters of the CMDiI-loaded nontargeted and the CMDiI-loaded targeted micelles were found to be 32 +/- 1 nm and 45 +/- 2 nm, respectively, as determined by dynamic light scattering (DLS). The zeta potentials for the nontargeted micelles (no CM-DiI-loaded), CM-DiI-loaded nontargeted micelles, and CM-DiI-loaded targeted micelles were found to be -6.5, -8.7, and - 13.5 mV, respectively. Evaluation of the in vitro release of CM-DiI from the MePEG-b-PVL micelles in phosphate buffer saline (0.01 M, pH = 7.4) containing 10% (v/v) fetal bovine serum at 37 degrees C revealed that approximately 20% of the probe was released within the first 2 h. Confocal laser scanning microscopy (CLSM) analysis revealed that the targeted micelles containing CM-DiI accumulated intracellularly in EGFR-overexpressing MDA-MB-468 breast cancer cells following a 2 h incubation period, while no detectable cell uptake was observed for the nontargeted micelles. Results obtained from the confocal images were confirmed in an independent study by measuring the intracellular CM-DiI fluorescence in cell lysate. In addition, the presence of free EGF was found to decrease the extent of uptake of the targeted micelles. Nuclear staining of the cells with Hoechst 33258 indicated that the targeted micelles mainly localized in the perinuclear region and some of the micelles were localized in the nucleus. These results demonstrate that the EGF-conjugated copolymer micelles developed in this study have potential as vehicles for targeting hydrophobic drugs to EGFR-overexpressing cancers.
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PMID:Epidermal growth factor-conjugated poly(ethylene glycol)-block- poly(delta-valerolactone) copolymer micelles for targeted delivery of chemotherapeutics. 1653 72

A series of leaving group derivatives of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes were synthesized and tested for cytotoxicity. The enantiomeric purity was determined by 1H NMR spectroscopy on the final diamines after derivation with (1R)-myrtenal. For coordination to platinum, the diamines were reacted with K2PtI4. The treatment of diiodoplatinum(II) complexes (4F-Ph/iProp-PtI2) with Ag2SO4 resulted in the sulfatoplatinum(II) complexes (4F-Ph/iProp-PtSO4), which can be easily transformed to dichloroplatinum(II) complexes (4F-Ph/iProp-PtCl2) with 2 n HCl. The importance of the leaving groups and the configuration at the diamine ligand on the antiproliferative effects was evaluated on the hormone-dependent MCF-7 and the hormone-independent MDA-MB 231 breast cancer cell lines as well as the LNCaP/FGC prostate cancer cell line. (R,R)-4F-Ph/iProp-PtCl2 was identified as the most active platinum(II) complex. The 3-methyl group increased antiproliferative effects relative to the [1,2-diamino-1-(4-fluorophenyl)butane]platinum(II) complexes described in an earlier study.
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PMID:Synthesis and cytotoxicity of enantiomerically pure [1,2-diamino-1-(4-fluorophenyl)-3-methylbutane]platinum(II) complexes. 1689 5

It is well accepted that estradiol (E2) plays an important role in the genesis and evolution of breast cancer. Quantitative evaluation indicates that in human breast tumor, estrone sulfate (E1S) 'via sulfatase' is a much more likely precursor for E2 than is androstenedione 'via aromatase'. In previous studies, it was demonstrated that in isolated MCF-7 and T-47D breast cancer cell lines, estradiol can block estrone sulfatase activity. In the present study, the effect of E2 was explored using total normal and cancerous breast tissues. This study was carried out with post-menopausal patients with breast cancer. None of the patients had a history of endocrine, metabolic or hepatic diseases or had received treatment in the previous 2 months. Each patient received local anaesthetic (lidocaine 1%) and two regions of the mammary tissue were selected: (A) the tumoral tissue and (B) the distant zone (glandular tissue) which was considered as normal. Samples were placed in liquid nitrogen and stored at -80 degrees C until enzyme activity analysis. Breast cancer histotypes were ductal and post-menopausal stages were T2. Homogenates of tumoral or normal breast tissues (45-75 mg) were incubated in 20 mM Tris-HCl, pH 7.2 with physiological concentrations of [3H]-E1S (5 x 10(-9)M) alone or in the presence of E2 (5 x 10(-5) to 5 x 10(-7) M) during 30 min or 3 h. E1S, E1 and E2 were characterized by thin layer chromatography and quantified using the corresponding standard. The sulfatase activity is significantly more intense with the breast cancer tissue than normal tissue, since the concentration of E1 was 3.20 +/- 0.15 and 0.42 +/- 0.07 pmol/mg protein, respectively after 30 min incubation. The values were 27.8 +/- 1.8 and 3.5 +/- 0.21 pmol/mg protein, respectively after 3 h incubation. Estradiol at the concentration of 5 x 10(-7) M inhibits this conversion by 33% and 31% in cancerous and normal breast tissues, respectively and by 53% and 88% at the concentration of 5 x 10(-5) M after 30 min incubation. The values were 24% and 18% for 5 x 10(-7) M and 49% and 42% for 5 x 10(-5) M, respectively after 3h incubation. It was observed that [3H]-E1S is only converted to [3H]-E1 and not to [3H]-E2 in normal or cancerous breast tissues, which suggests a low or no 17beta-hydroxysteroid dehydrogenase (17beta-HSD) Type 1 reductive activity in these experimental conditions. In conclusion, estradiol is a strong anti-sulfatase agent in cancerous and normal breast tissues. This data can open attractive perspectives in clinical trials using this hormone.
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PMID:Estradiol inhibits the estrone sulfatase activity in normal and cancerous human breast tissues. 1748 87

A protein exhibiting an N-terminal amino acid sequence with some similarity to imidazoleglycerol phosphate synthase was purified from fresh Capparis spinosa melon seeds. The purification protocol entailed anion exchange chromatography on DEAE-cellulose, cation exchange chromatography on SP-Sepharose, and finally gel filtration by fast protein liquid chromatography on Superdex 75. The protein was adsorbed using 20 mM Tris-HCl buffer (pH 7.4) and desorbed using 1 M NaCl in the starting buffer from the DEAE-cellulose column and SP-Sepharose column. The protein demonstrated a molecular mass of 38 kDa in gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, indicating that it was monomeric. The protein inhibited proliferation of hepatoma HepG2 cells, colon cancer HT29 cells and breast cancer MCF-7 cells with an IC(50) of about 1, 40 and 60 microM, respectively. It inhibited HIV-1 reverse transcriptase with IC(50) of 0.23 microM. It inhibited mycelial growth in the fungus, Valsa mali. It did not exhibit hemagglutinating, ribonuclease, mitogenic or protease inhibitory activities.
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PMID:A protein with antiproliferative, antifungal and HIV-1 reverse transcriptase inhibitory activities from caper (Capparis spinosa) seeds. 1901 43

A short description selected from the presentations which had been awarded prizes in the 4th International Meeting of Nuclear Medicine, of the Hellenic Society of Nuclear Medicine, in Thessaloniki, Greece, is as follows: Professor L.G. Strauss from Heidelberg received the first prize for his original paper under the title: "Modulation of FDG kinetics in tumors by gene expression". He studied 25 patients with colorectal tumors with dynamic PET-FDG within 2 days prior to surgery and he finally came to the conclusion that angiogenesis has a significant impact primarily on the kinetic data (k1, k3), but also on the global FDG uptake. A detailed analysis of the FDG kinetics can help to classify the grade of angiogenesis in primary colorectal tumors. The cell cycle associated genes have a comparable impact on the FDG kinetics as compared to the angiogenesis related genes. Furthermore, hypoxia was associated with the FDG parameters. Enhanced expression of HIF-1a was primarily associated with an enhanced influx of FDG. The results demonstrated the impact of dedicated groups of genes on the FDG kinetics. Furthermore, if the FDG kinetics are quantitatively analyzed, the expression of certain genes may be predicted from these data. Dr. P. Bouziotis et al. received the second prize for their original paper under the title: "Labeling of bevacizumab, an anti-VEGF monoclonal antibody, with technetium-99m and rhenium-188". The authors were from Athens and Oxford and studied the reduction of the endogenous disulphide bonds of bevacizumab by treatment with 2-mercaptoethanol and TCEP-HCl. The number of generated-SH groups was estimated before each labelling experiment. The results of the present study show that VEGF expression in tumors can be detected and visualized specifically with the anti-VEGF monoclonal antibody bevacizumab, labelled with gamma-emitting radioisotopes. The third prize went to Dr C. H. Tsopelas et al. from Adelaide who presented an original paper under the title: "Evaluation of visceral sensitivity after transient inflammation-An experimental model". Their aim was to characterise the inflammatory response to the transient chemically-induced colitis after instillation of trinitrobenzenesulfonic acid. Inflammation was tested by (99m)Tc-Sn-colloid-leucocytes. They concluded that the Group of Lewis rats compared to Fisher rats, developed a prolonged visceral hyperalgesia and more severe inflammation following colorectal instillation of TNBS/ethanol doses, possibly involving the systemic immune response. The Lewis rat species appears to be a good model of transient colitis, because of its heightened sensitivity to the chemical stimulus, and due to detectable visceral changes long after administration of the above stimulus. Professor A.M. Peters from England, received the fourth prize with his original paper: "New quantitative techniques for investigating and predicting lymphoedema resulting from breast cancer treatment". In lymphoedema from breast cancer treatment he investigated local uptake via putative peripheral lympho-venous communications (LVCs), using intradermally injected labelled red cells. He concluded that his results suggest that protective mechanisms could include i) interstitial proteolysis, ii) increased peripheral trans-endothelial protein transport or iii) development of peripheral LVCs. Other prizes were awarded to: Professor G.P. Bandopadhyaya et al. from New-Delhi for their original paper: "Molecular targetting of infective bacterial maltose binding protein for infection imaging using Tc-99m hydroxypropyl cyclodextrin in patients with knee joint replacement and other prostheses", to Dr P.J. Marsouvanidis et al. from Demokritos Athens and Patras for their original paper: "Synthesis, radiochemistry and preclinical comparison of [(111)In-DOTA(0)]SS-14 and [(111)In-DOTA(0),(D)Trp(8)]SS-14 in AR4-2J cells and Swiss albino mice", to Professor B. Singh et al. from Chandigarh and New Delhi for their original paper: "Efficacy of indigenously developed single vial kit preparation of (99m)Tc-ciprofloxacin in the detection of bacterial infection-An Indian experience" and to Dr. A. Bantis et al. from Alexandroupolis for their original paper: "The prognostic value of serum chromogranin A in patients with advanced prostate cancer".
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PMID:Highlights and prizes of an international meeting. 1908 55

From the dried fruiting bodies of the toxic mushroom Inocybe umbrinella, a novel lectin with a molecular mass of 17 kDa has been isolated with about 160-fold purification. The purification protocol comprised ion exchange chromatography on DEAE-cellulose, and CM-cellulose, and gel filtration on Superdex 75. Among the carbohydrates tested, raffinose, d-melibiose, alpha-lactose and d(+)-galactose could inhibit the hemagglutinating activity of the lectin. The hemagglutinating activity was stable between 10 and 60 degrees C, in 12.5-100mM HCl, and in 50mM NaOH. The hemagglutinating activity was inhibited by Ca(2+), Mn(2+)and Mg(2+) ions, but was unaffected by Fe(3+), Zn(2+) and Al(3+) ions. The lectin inhibited HIV-1 reverse transcriptase with an IC(50) of 4.7+/-0.2 microM. Proliferation of tumor cells including hepatoma HepG2 cells and breast cancer MCF7 cells was inhibited by the lectin with an IC(50) of 3.5+/-0.2 microM and 7.4+/-0.3 micoM, respectively. The lectin has a unique N-terminal amino acid sequence, DGVLATNAVA. It did not exhibit antifungal activity. The present report is the first on an Inocybe lectin and represents one of the very few reports on lectins from toxic mushrooms.
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PMID:Purification and characterization of a novel lectin from the toxic wild mushroom Inocybe umbrinella. 1911 67

We have recently reported that cytostatic concentrations of the microsomal antiestrogen-binding site (AEBS) ligands, such as PBPE (N-pyrrolidino-(phenylmethyphenoxy)-ethanamine,HCl) and tamoxifen, induced differentiation characteristics in breast cancer cells through the accumulation of post-lanosterol intermediates of cholesterol biosynthesis. We show here that exposure of MCF-7 (human breast adenocarcinoma cell line) cells to higher concentrations of AEBS ligands triggered active cell death and macroautophagy. Apoptosis was characterized by Annexin V binding, chromatin condensation, DNA laddering and disruption of the mitochondrial functions. We determined that cell death was sterol- and reactive oxygen species-dependent and was prevented by the antioxidant vitamin E. Macroautophagy was characterized by the accumulation of autophagic vacuoles, an increase in the expression of Beclin-1 and the stimulation of autophagic flux. We established that macroautophagy was sterol- and Beclin-1-dependent and was associated with cell survival rather than with cytotoxicity, as blockage of macroautophagy sensitized cells to AEBS ligands. These results show that the accumulation of sterols by AEBS ligands in MCF-7 cells induces apoptosis and macroautophagy. Collectively, these data support a therapeutic potential for selective AEBS ligands in breast cancer management and shows a mechanism that explains the induction of autophagy in MCF-7 cells by tamoxifen and other selective estrogen receptor modulators.
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PMID:Ligands of the antiestrogen-binding site induce active cell death and autophagy in human breast cancer cells through the modulation of cholesterol metabolism. 1952 24


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