MCF-7 Human Cells Research Articles

The Impact of Insulin on Low-dose Metronomic Vinorelbine and Mafosfamide in Breast Cancer Cells.

Breast cancer (BC) may be affected by diabetes and anti-diabetic medication, as well as its therapeutic agents. Low-dose metronomic chemotherapy (LDMC) is an available treatment option in BC. We investigated the impact of insulin on low-dose metronomic vinorelbine and mafosfamide in BC cell lines. Human BC cell lines T-47D, MCF-7, MDA-MB-231, BT-549 and non-tumorigenic breast cell line MCF-10A were exposed to 0.01 μg/ml and 10 μg/ml insulin in combination with low-dose metronomic vinorelbine or mafosfamide. The cell viability was determined after 24-72 hours using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Insulin, especially at a concentration of 10 μg/ml, seemed to increase viability of vinorelbine-treated hormone receptor-positive BC cells, whereas low-dose mafosfamide treatment tended to be potentiated by insulin in triple-negative cells. Our findings suggest that insulin may influence the cytotoxic activity of LDMC depending on insulin concentration, type of cytotoxic drug used and BC cell line.

A new biflavonoids from Aster tataricus induced non-apoptotic cell death in A549 cells

A new biflavonoids, (2R,2''R)-7-O-methyl-2,3,2'',3''-tetrahydrorobustaflavone (1), along with five known flavonoids (2-6) were isolated from the MeOH extract of Aster tataricus. Among them, compounds 1-2 were the C-3'-C-6'' type biflavonoids obtained from the genus Aster for the first time. The structures and absolute configurations of compound 1 was confirmed based on extensive spectroscopic and circular dichroism analyses. Compound 1 exhibited moderate cytotoxicity against seven human cancer A549, HepG2, PC3, DU145, MCF-7, LOVO and NCI-H1975 cell lines. Compound 1 remarkably inhibited the proliferation of A549 cancer cells with IC50 value of 5.4 μM. Further preliminary pharmacological study, 1 induces A549 cell death by non-apoptotic forms through flow cytometry and cell scratch assay data.

Chlamydial clinical isolates show subtle differences in persistence phenotypes and growth in vitro.

Urogenital Chlamydia trachomatis infection is the most common sexually transmitted bacterial infection throughout the world. While progress has been made to better understand how type strains develop and respond to environmental stress in vitro, very few studies have examined how clinical isolates behave under similar conditions. Here, we examined the development and persistence phenotypes of several clinical isolates, to determine how similar they are to each other, and the type strain C. trachomatis D/UW-3/Cx. The type strain was shown to produce infectious progeny at a higher magnitude than each of the clinical isolates, in each of the six tested cell lines. All chlamydial strains produced the highest number of infectious progeny at 44 h post-infection in the McCoy B murine fibroblast cell line, yet showed higher levels of infectivity in the MCF-7 human epithelial cell line. The clinical isolates were shown to be more susceptible than the type strain to the effects of penicillin and iron deprivation persistence models in the MCF-7 cell line. While subtle differences between clinical isolates were observed throughout the experiments conducted, no significant differences were identified. This study reinforces the importance of examining clinical isolates when trying to relate in vitro data to clinical outcomes, as well as the importance of considering the adaptations many type strains have to being cultured in vitro.

Proteolytic Targeting Chimeras with Specificity for Plasma Membrane and Intracellular Estrogen Receptors.

Decisions regarding the assignment of hormonal therapy for breast cancer are based solely upon the presence of nuclear estrogen receptors (ERs) in biopsied tumor tissue. This is despite the fact that the G-protein-coupled estrogen receptor (GPER) is linked to advanced breast cancer and is required for breast cancer stem cell survival, an observation that suggests that effective endocrine therapy should also target this receptor. Here, two ER/GPER-targeting proteolytic chimeras (UI-EP001 and UI-EP002) are described that effectively degrade ERα, ERβ, and GPER. These chimeras form high-affinity interactions with GPER and ER with binding dissociation constants of ∼30 nM and 10-20 nM, respectively. Plasma membrane and intracellular GPER and nuclear ER were degraded by UI-EP001 and UI-EP002, but not by a partial proteolytic targeting chimera (PROTAC) lacking its estrogen-targeting domain. Pretreatment of cells with the proteasomal inhibitor, MG132, blocked UI-EP001 and UI-EP002 proteolysis, while the lysosomotrophic inhibitor, chloroquine, had no effect. The off-target activity was not observed against recombinant β1-adrenergic receptor or CXCR4. Target specificity was further demonstrated in human MCF-7 cells where both drugs effectively degraded ERα, ERβ, and GPER, sparing the progesterone receptor (PR). UI-EP001 and UI-EP002 induced cytotoxicity and G2/M cell cycle arrest in MCF-7 breast cancer and human SKBR3 (ERα-ERβ-GPER+) breast cancer cells but not human MDA-MB-231 breast cancer cells that do not express functional GPER/ER. These results suggest that it is possible to develop a receptor-based strategy of antiestrogen treatment for breast cancer that targets both plasma membrane and intracellular estrogen receptors.

Synthesis of Bioactive Diarylheptanoids from Alpinia officinarum and Their Mechanism of Action for Anticancer Properties in Breast Cancer Cells.

An efficient synthesis of the Alpinia officinarum-derived diarylheptanoids, viz., enantiomers of a β-hydroxyketone (1) and an α,β-unsaturated ketone (2) was developed starting from commercially available eugenol. Among these, compound 2 showed a superior antiproliferative effect against human breast adenocarcinoma MCF-7 cells. Besides reducing clonogenic cell survival, compound 2 dose-dependently increased the sub G1 cell population and arrested the G2-phase of the cell cycle, as revealed by flow cytometry. Mechanistically, compound 2 acts as an intracellular pro-oxidant by generating copious amounts of reactive oxygen species. Compound 2 also induced both loss of mitochondrial membrane potential (MMP) as well as lysosomal membrane permeabilization (LMP) in the MCF-7 cells. The impaired mitochondrial and lysosomal functions due to reactive oxygen species (ROS)-generation by compound 2 may contribute to its apoptotic property.

Design, synthesis, crystal structure, molecular docking studies of some diorganotin(IV) complexes derived from the piperonylic hydrazide Schiff base ligands as cytotoxic agents

Inspired by the role of organotin(IV) complexes in inhibition of cancer cell growth and interaction with different target proteins, we have synthesized a series of new organotin(IV) complexes of Schiff base ligands of benzylidene benzohydrazide analogues. The structural elucidation of compounds was done by spectroscopic studies showing tridentate nature (NOO) of Schiff base ligands having pentacoordinated geometry around the central tin metal. The X-ray crystallographic study of complex 9 (Me2SnL2) revealed the distorted trigonal bipyramidal geometry (SnO2NC2). The cytotoxic activity of compounds was tested against human cancer cell lines A549, Hela, MCF7 and normal cell line L6 using MTT assay. Compound 12 (Ph2SnL2), 14 (Et2SnL3), 19 (Bu2SnL4) was found most active against tested cell lines having IC50 value 22.909–32.303 μM. Further, molecular docking study was performed for the active compounds 12, 14 and 20 at 3D space of enzymes Tyrosine kinase and EGFR kinase domain.

Towards understanding antimicrobial activity, cytotoxicity and the mode of action of dichapetalins A and M using in silico and in vitro studies

Dichapetalum madagascariense Poir (Dichapetalaceae) is traditionally used to treat bacterial infections, jaundice, urethritis and viral hepatitis in Africa. Its root contains a broad spectrum of biologically active dichapetalins. To evaluate the plant's effect on human MCF-7 cells and its' antibacterial and antiparasitic potentials, we isolated and identified the known dichapetalins A and M from the roots. Both dichapetalins were tested on six bacterial strains (Shigella flexneri, Bacillus cereus, Salmonella paratyphi B, Listeria monocytogenes, Escherichia coli, Staphylococcus aureus) and two parasite strains; Trypanosoma brucei brucei, and Leishmania donovani using the Alamar Blue assay system. Dichapetalins A and M were more potent against B. cereus with IC50 values of 11.15 and 3.15 μg/ml, respectively, compared to the positive control ampicillin (IC50 = 19.50 μg/ml). Dichapetalins A (IC50 = 74.22 μg/ml) and M (IC50 = 72.34 μg/ml) were less active against T. b. brucei, compared to the standard Suramin (IC50 = 4.96 μg/ml). Dichapetalin M showed moderate activity against L. donovani (Amphotericin B: IC50 = 0.21 μg/ml) with an IC50 of 16.80 μg/ml. In human MCF-7 cells expressing the NR1I2 receptor, the activity of dichapetalin M was higher (IC50 = 4.71 μM and 3.95 μM) for 48 and 72 h of treatment, respectively compared to Curcumin with IC50 of 17.49 μM and 12.53 μM for 48 and 72 h of treatment, respectively. Results from in vitro expression studies with qPCR confirmed an antagonistic effect of dichapetalin M on PXR (NR1I2) signaling; supporting the PXR signaling pathway as a possible mode of action of dichapetalin M as predicted by in silico results. These findings confirm previous studies that D. madagascariense can be a source of potential lead compounds for development of novel antibiotic, antiparasitic and anticancer medicines, and provide further insights into the mechanism of action of the dichapetalins.

New C21-steroidal aglycones from the roots of Cynanchum otophyllum and their anticancer activity

Naturally occurring C21-steroidal aglycones from Cynanchum exhibit significant antitumor effects. To expand the chemical diversity and get large scale C21-steroidal aglycones, the extracts of the roots of Cynanchum otophyllum were treated with 5% HCl in aqueous and the resulting hydrolysate was investigated. Nine new C21-steroidal aglycones (1–9) namely cynotogenins A-I, along with seventeen known analogous (10–26), were isolated from the hydrolysate. The structures of compounds 1–9 were elucidated by spectroscopic analysis (IR, HR-ESI-MS, 1D and 2D NMR) and comparison of observed spectroscopic data with those of reported in the literature. Aglycones 2–5 with rare cis-cinnamoyl group as well as 8 and 9 with 5β,6β-epoxy group were found from the genus of Cynanchum for the first time. The cytotoxicities of compounds 1–26 toward human cancer HeLa, H1299, HepG2, and MCF-7 cells were evaluated and preliminary structure-activity relationship (SAR) was discussed. Moreover, compound 20 inhibits HepG2 cell apoptosis and induces of G0/G1 phase arrest in a dose dependent manner.

Anti-Proliferative Activity of Glucagon-Like Peptide-1 Receptor Agonist on Obesity-Associated Breast Cancer: The Impact on Modulating Adipokines' Expression in Adipocytes and Cancer Cells.

Obesity is associated with high risk and poor prognosis of breast cancer (BC). Obesity promotes BC cells proliferation via modulating the production of adipokines, including adiponectin (anti-neoplastic adipokine), leptin (carcinogenic adipokine) and inflammatory mediators. In the present study we investigated the anti-proliferative effects of liraglutide (LG; anti-diabetic and weight reducing drug) on MCF-7 human BC cells cultured in obese adipose tissue-derived stem cells-conditioned medium (ADSCs-CM) and whether this effect is mediated via modulating the adipokines in ADSCs and cancer cells. Proliferation was investigated using AlamarBlue viability test, colony forming assay and cell cycle analysis. Levels and expression of adipokines and their receptors were assayed using ELISA and RT-PCR. LG caused 48% inhibition of MCF-7 proliferation in obese ADSCs-CM, reduced the colony formation and induced G0/G1 phase arrest. LG also decreased the levels of inflammatory mediators, suppressed the expression of leptin, while increased mRNA levels of adiponectin and their receptors in obese ADSCs and cancer cells cultured in obese ADCSs-CM. In conclusion, LG could mitigate BC cell growth in obese subjects; therefore it could be used for clinical prevention and/or treatment of BC in obese subjects. It may assist to improve treatment outcomes and, reduce the mortality rate in obese patients with BC.

Methoxy and bromo scans on N-(5-methoxyphenyl) methoxybenzenesulphonamides reveal potent cytotoxic compounds, especially against the human breast adenocarcinoma MCF7 cell line

Thirty seven N-(5-methoxyphenyl)-4-methoxybenzenesulphonamide with methoxy or/and bromo substitutions (series 1-4) and with different substituents on the sulphonamide nitrogen have been synthesised. 21 showed sub-micromolar cytotoxicity against HeLa and HT-29 human tumour cell lines, and were particularly effective against MCF7. The most potent series has 2,5-dimethoxyanilines, especially the 4-brominated compounds 23–25. The active compounds inhibit microtubular protein polymerisation at micromolar concentrations, thus pointing at tubulin as the target. Co-treatment with the MDR inhibitor verapamil suggests that they are not MDR substrates. Compound 25 showed nanomolar antiproliferative potency. It severely disrupts the microtubule network in cells and arrests cells at the G2/M cell-cycle phase, thus confirming tubulin targeting. 25 triggered apoptotic cell death, and induced autophagy. Docking studies suggest binding in a distinct way to the colchicine site. These compounds are promising new antitumor agents acting on tubulin.

Effect of Lutein-Rich Extract on Human Cancer cells

Background: Lutein and its isomerzeaxanthin are safe natural compounds. They are able to reduce the development of tumor and other chronic diseases. The objectives of the current study was to examine the cytotoxicity of lutein isolated and purified from alfalfa, safe and low-cost plant, on five different human cancer cell lines, namely (MCF-7), (HepG2), (A549), (PC3), and (HCT116), as well as normal (HFB4) cells. Method: We examined the cytotoxicity of lutein purified from Medicago sativa L and evaluate its activity against human liver HepG2, breast MCF-7, lung A549, prostate PC3, and colon HCT116 cancer cell lines using SRB assay in comparison with doxorubicin as a reference drug. Results: Results revealed that the tested extract could be a more promising anticancer agent in the case of MCF-7 (IC50, 3.10±0.47 μg/ml) compared with standard drug doxorubicin (IC50, 2.90±0.30 μg/ml). Moreover, the extract showed a moderate effect on HepG2 (IC50, 6.11±0.84 μg/ml) versus doxorubicin (IC50, 2.90±0.30 μg/ml); meanwhile, the extract showed no activity against A549, PC3, and HCT116 cells. The results further revealed that the extract had no toxicity against the growth of normal HFB4 cells versus doxorubicin. Conclusion: Lutein-rich extract from alfalfa had a major antiproliferative role in breast MCF-7 and liver HepG2 compared to doxorubicin.

Gene regulation gravitates toward either addition or multiplication when combining the effects of two signals.

Two different cell signals often affect transcription of the same gene. In such cases, it is natural to ask how the combined transcriptional response compares to the individual responses. The most commonly used mechanistic models predict additive or multiplicative combined responses, but a systematic genome-wide evaluation of these predictions is not available. Here, we analyzed the transcriptional response of human MCF-7 cells to retinoic acid and TGF-β, applied individually and in combination. The combined transcriptional responses of induced genes exhibited a range of behaviors, but clearly favored both additive and multiplicative outcomes. We performed paired chromatin accessibility measurements and found that increases in accessibility were largely additive. There was some association between super-additivity of accessibility and multiplicative or super-multiplicative combined transcriptional responses, while sub-additivity of accessibility associated with additive transcriptional responses. Our findings suggest that mechanistic models of combined transcriptional regulation must be able to reproduce a range of behaviors.

Apoptosis in Response to Anti-estrogens in MCF-7 Human Mammary Adenocarcinoma Cells

Programmed Cell Death (PCD) is a highly regulated but not yet fully understood process by which selective gene expression leads to cell demise. The term apoptosis refers to the typical morphological changes observed with PCD. In the present study, we investigated the potential role of apoptosis as a mechanism by which anti-estrogens mediate tumor regression. Estrogen receptor-positive MCF-7 human mammary adenocarcinoma cells were treated with three different estrogen antagonists: RU 58668, ICI 182,780, and 4OH-Tam, in order of increasing potency. At selected time intervals, for up to seven days of culture, the degree of apoptosis induced by the anti-estrogens was assessed. Apoptotic cells were scored on the basis of specific morphological criteria disernable by fluorescence microscopy. It was hypothesised that the more potent the anti-estrogen, the greater the number of apoptotic cells we would observe. However, only minimal apoptosis was noted even at the highest concentration of anti-estrogen assayed (10-5 M). This is in contrast to some, but not all, previous reports. Possible confounding factors are discussed and include the presence of exogenous estrogen in the culture media, as well as a genetic drift in the clonal lineage of MCF-7 cells such that a resistance to induced apoptosis had been acquired.

Arbolodinines A−C, biologically-active aspidofractinine-aspidofractinine, aspidofractinine-strychnan, and kopsine-strychnan bisindole alkaloids from Kopsia arborea

Three new bisindole alkaloids, arbolodinines A−C, comprising aspidofractinine-aspidofractinine, aspidofractinine-strychnan, and kopsine-strychnan alkaloids, respectively, were isolated from the stem bark extract of the Malayan Kopsia arborea . The structures of the alkaloids were elucidated based on analysis of the spectroscopic data while the absolute configurations were established based on experimental and calculated ECD data. Arbolodinine A is characterized by the union of two aspidofractinine halves with rare and unusual branching from C-5′ of an iminium/carboxylate zwitterion of one aspidofractinine half to the olefinic C-14 of the other aspidofractinine half, while arbolodinines B and C represent first examples of aspidofractinine-strychnan and kopsine-strychnan bisindoles, respectively. Arbolodinine B displayed pronounced cytotoxic effects against an array of human cancer cell lines, including KB, vincristine-resistant KB, PC-3, HCT 116, HT-29, MDA-MB-231, MCF7 and A549 cells with IC 50 values ranging from 1.3 to 9.6 μM. • Three new bisindole alkaloids, arbolodinines A−C were isolated from Kopsia arborea. • Arbolodinine A is an aspidofractinine-aspidofractinine type bisindole. • Arbolodinine B is an aspidofractinine-strychnan type bisindole. • Arbolodinine C is a kopsine-strychnan type bisindole. • Arbolodinine B showed strong cytotoxicity against an array of human cancer cells.

New 3,4-seco-diterpene and coumarin derivative from the leaves of Trigonostemon flavidus Gagnep

Two new compounds named trigoflavidus A (1) and trigoflavidus B (2), and eight known compounds, trigoflavidone (3), heterophypene (4), howpene C (5), 3,4-seco-sonderianol (6), trigonochinene C (7), fraxidin (8), isofraxidin (9), and isofraxetin (10) were isolated from the leaves of Trigonostemon flavidus Gagnep. by various chromatographic methods. Their chemical structures were elucidated via UV, IR, HR-ESI-MS and NMR spectroscopic methods and divided into two groups including six 3,4-seco-diterpenes (1, 3-7) and four coumarins (2, 8-10). Absolute configurations at stereocenters of compound 1 were confirmed by comparison of its CD spectra with those of the TD-DFT calculations. At a concentration of 30 µM, compounds 1–10 exhibited weak cytotoxic activity toward LU1, HepG2, MCF7, and SKMel2 human cell lines (cell viability all over 50%).

Furan Derivatives and Polyketides from the Fungus Irpex lacteus

Eight new furan derivatives, irpexins A‒H (1‒8), two new polyketides, irpexins I and J (9 and 10), together with nine known compounds were isolated from the fermentation of Irpex lacteus. The structures and absolute configurations were elucidated on the basis of extensive spectroscopic methods and Mosher ester reaction. All compounds shows no cytotoxicity to human MCF-7 and Hela cancer cell lines at the concentration of 10 μM.Graphic

Tryptanthrin exerts anti-breast cancer effects both in vitro and in vivo through modulating the inflammatory tumor microenvironment.

Tryptanthrin is an indole quinazoline alkaloid from the indigo-bearing plants, such as Isatis indigotica Fort. Typically, this natural compound shows a variety of pharmacological activities such as antitumor, antibacterial, anti-inflammatory and antioxidant effects. This study was conducted to assess the antitumor activity of tryptanthrin in breast cancer models both in vitro and in vivo, and to explore the important role of the inflammatory tumor microenvironment (TME) in the antitumor effects of tryptanthrin. Human breast adenocarcinoma MCF-7 cells were used to assess the antitumor effect of tryptanthrin in vitro. MTT assay and colony formation assay were carried out to monitor the antiproliferative effect of tryptanthrin (1.56~50.0 μmol L-1) on inhibiting the proliferation and colony formation of MCF-7 cells, respectively. The migration and invasion of MCF-7 cells were evaluated by wound healing assay and Transwell chamber assay, respectively. Moreover, the 4T1 murine breast cancer model was established to examine the pharmacological activity of tryptanthrin, and three groups with different doses of tryptanthrin (25, 50 and 100 mg kg-1) were set in study. Additionally, tumor volumes and organ coefficients were measured and calculated. After two weeks of tryptanthrin treatment, samples from serum, tumor tissue and different organs from tumor-bearing mice were collected, and the enzyme-linked immunosorbent assay (ELISA) was performed to assess the regulation of inflammatory molecules in mouse serum. Additionally, pathological examinations of tumor tissues and organs from mice were evaluated through hematoxylin and eosin (H&E) staining. The expression of inflammatory proteins in tumor tissues was measured by immunohistochemistry (IHC) and Western blotting. Tryptanthrin inhibited the proliferation, migration and invasion of MCF-7 cells, up-regulated the protein level of E-cadherin, and down-regulated those of MMP-2 and Snail, as suggested by the MCF-7 cell experiment. According to the results from in vivo experiment, tryptanthrin was effective in inhibiting tumor growth, and it showed favorable safety without inducing the fluctuations of body mass and organ coefficient (p > 0.05). In addition, tryptanthrin also suppressed the expression levels of NOS1, COX-2 and NF-κB in mouse tumor tissues, and regulated those of IL-2, IL-10 and TNF-α in the serum of tumor cells-transplanted mice. Tryptanthrin exerted its anti-breast cancer activities through modulating the inflammatory TME both in vitro and in vivo.

Phytochemical Analysis, In vitro Assessment of Antioxidant Properties and Cytotoxic Potential of Ruta chalepensis L. Essential Oil

: Ruta chalepensis L. (Rutaceae) is an aromatic herb used in traditional medicine in Jordan and many countries. The main aims of this study are to isolate and identify the components of the essential oil from the aerial parts of R. chalepensis. Determination of the total phenolic and flavonoid contents, in addition to the in vitro assessment of antioxidant capacity as well as the cytotoxic effect of the essential oil extract on human MCF-7, T47D and Caco-2 cancer cell lines. The oil extract was analyzed using gas chromatography-mass spec- trometry (GC-MS). The major components of the essential oil were 2-cyclohexen-1-one,3-[(2,3,4,9 tetrahydro 1H pyrido[3,4 b]indole-1-yl) methyl]- (45.97 %) and 2-Nonanone (19.45 %). The total phenolic was 5.00 ± 0.005 mg gallic acid equivalent/ g of oil extract, while the total flavonoid content was 34.09 ± 0.140 mg quercetin equivalent/ g oil. The antioxidant properties were screened using DPPH radical scavenging assay (IC50 was 35.27 μg/ml) and the reducing power ability (EC50 was 20110 μg/ml). The cytotoxic activity was assessed using the MTT assay. The cytotoxicity of oil extract in all tested cell lines was in a dose-dependent manner. The calculated IC50 values of the oil extract against MCF-7, T47D and Caco-2 (79.32±0.948 μg/ml, 97.23±0.57 μg/ml, 107.72±1.85 μg/ml), respectively. Furthermore, there was no significant inhibitory effect of the oil extract on the normal human fibro-blast cell line (MRC-5). This study demonstrated that R. chalepensis essential oil possesses antioxidant activity and could be considered as a potential source of the anticancer compound.

Role of Endothelin 1 on Proliferation and Migration of Human MCF-7 Cells.

The aim of this study was to explore the role of endothelin 1 (ET-1) in human breast cancer proliferation and migration and antagonism of endothelin receptor A (ETAR) and endothelin receptor B (ETBR) by using the non-selective dual ETA/ETB receptor antagonist bosentan and determine its anti-proliferative, anti-metastatic, and apoptotic effects demonstrated by nuclear factor kappa B (NF-kB), vascular endothelial growth factor (VEGF), Caspase 3 and Caspase 9 expression on endothelin-induced proliferation of MCF-7 cell line in vitro. A total of 8,000 cells were seeded into e-plates 24 hours after the cells were incubated with or without 10-4 M BOS (1 hour before ET-1 treatment); 10-7, 10-8, and 10-9 M ET-1 for 1-4 days. Whether ET-1 is present or not in the tumor area, bosentan exerts anti-proliferative effect on breast cancer. However, ET-1 and bosentan group showed important inhibitory effect on tumor migration compared to bosentan alone, which can be attributed to increased activity of ET-1 axis in the presence of ET-1. The imbalance among the NF-kB, caspases, and VEGF, which are predictive factors of carcinogenesis significantly improved after bosentan administration. Our study definitely demonstrated ET-1 and its critical role in cancer progression with apoptotic and anti-apoptotic pathways (NF-κB) and VEGF expression, and migration analyses were also performed. The second major finding was that bosentan inhibited ET-1-mediated effects on tumor proliferation and migration.

Deciphering of The Effect of Chemotherapeutic Agents on Human Glutathione S-Transferase Enzyme and MCF-7 Cell Line.

Cancer is the disease that causes the most death after cardiovascular diseases all over the world these days. Breast cancer is the most common type of cancer among women and ranks the second among cancer-related deaths after lung cancer. Chemotherapeutics act by killing cancer cells, preventing their spread and slowing their growth. Recent studies focus on the effects of chemotherapeutics on cancer cells and new chemotherapy approaches that targeting enzymes that catalyze important metabolic reactions in the cell. The aim of this study was to investigate the effects of chemotherapeutic agents, Tamoxifen and 5-FU, on MCF-7 cell line and human erythrocyte GST, an important enzyme of intracellular antioxidant metabolism. In this study, it was investigated that the effect of chemotherapeutic agents, Tamoxifen and 5-FU, on MCF-7 breast cancer cell line and performed ROS analyzes. In addition, it was purified glutathione S-transferase (GST), one of the important enzymes of intracellular antioxidant mechanism, from human erythrocytes by using ammonium sulfate precipitation and glutathione agarose affinity chromatography, and investigated in vitro effects of chemotherapeutic agents, 5 - FU and Tamoxifen, on the activity of this enzyme for the first time. it was determined that Tamoxifen and 5-FU inhibited cellular viability and 5-FU increased intracellular levels of ROS, whereas Tamoxifen reduced intracellular levels of ROS. In addition, human erythrocyte GST enzyme with 16.2 EU/mg specific activity was purified 265.97-fold with a yield of 35% using ammonium sulfate precipitation and glutathione agarose affinity chromatography. The purity of the enzyme was checked by the SDS-PAGE method. In vitro effects of chemotherapeutics, 5-FU and Tamoxifen, on GST activity purified from human erythrocytes were investigated. The results showed that 5-FU increased the activity of GST in the concentration range of 77 to 1155 μM and that Tamoxifen increased the activity of GST in the concentration range of 0.54 to 2.70 μM. In this study, the effects of tamoxifen and 5-FU chemotherapeutic agents on both MCF-7 cell line and human GST enzyme were examined together for the first time. Our study showed that chemotherapeutic agents (5-FU and Tamoxifen) inhibited cellular viability and Tamoxifen reduced intracellular levels of ROS whereas 5-FU increased intracellular levels of ROS. In addition, 5-FU and Tamoxifen were found to increase the activity of GST enzyme purified from the human erythrocyte.