Human Ovarian Carcinoma SKOV3 Cells Research Articles

Melatonin enhances cell death and suppresses the metastatic capacity of ovarian cancer cells by attenuating the signaling of multiple kinases

BackgroundOvarian cancer is a highly aggressive disease that is frequently diagnosed in advanced stages. Melatonin, with its numerous antitumor properties, holds great promise in cancer treatment. Herein, we investigated the effects of melatonin on apoptosis, cell migration, and kinase levels in human ovarian carcinoma SKOV-3 cells and determined whether these effects are mediated by the activation of the MT1 receptor. MethodsSKOV-3 cells were exposed to different concentrations of melatonin based on the presence of MT1 receptor, and we also performed specific silencing of the melatonin receptor gene MTNR1A. ResultsOur findings revealed that melatonin reduced cell viability as shown by the MTT assay, and flow cytometry analysis showed increased rates of apoptosis and necrosis in all melatonin-treated cells. Melatonin significantly decreased the migratory and invasive capacities of the cells. Propidium iodide labeling indicated that melatonin induced cell cycle arrest by reducing DNA content in the S and G2/M phases in SKOV-3 cells. Additionally, the levels of AKT, ERK1/2, JNK, CREB, p70S6K, STAT3/5, and p38 MAP kinase involved in cell survival, proliferation, motility, and stress responses were depressed by melatonin and further reduced after MT1 knockdown. These molecules were found to be associated with lower overall survival in ovarian cancer patients. ConclusionsMelatonin had obvious oncostatic actions on ovarian cancer cells, and MT1 receptor knockdown intensified its antitumor effect. The inhibition of the MT1 receptor resulted in a substantial reduction in the migratory and invasive capacities of the cells, suggesting its potential as a therapeutic target for the treatment of ovarian cancer.

Catechin, rutin and quercetin in Quercus mongolica Fisch leaves exert inhibitory effects on multiple cancer cells.

We aimed to identify anti-tumor agents in Quercus mongolica Fisch (QMF). Bioactive compounds in QMF leaves, which were extracted using ethanol as a co-solvent. Five point zero six grams of flavonoids were obtained from 100 g of QMF leaves. Catechin (18.4%), rutin (6.3%), ellagic acid (34.9%), quercetin (5.1%) and kaempferol (20.6%) are the main ingredients of the extracts and were further purified by HPLC. CCK-8 cell proliferation assay showed that catechin and ellagic acid exerted strong inhibitory effects on the proliferation of all cancer cells with lower IC50 values against MCF-7 human breast cancer cell lines, SMMC-7721 human hepatocellular carcinoma cells, HeLa human cervical carcinoma cell lines and SKOV3 human ovarian carcinoma cell lines (p < .05). Catechin, rutin and quercetin induced a higher rate of apoptosis and inhibited all cancer cell proliferation by inducing the G0/G1 phase and G2/M phase arrest (p < .05). However, ellagic acid induced tumor cell death, not through apoptosis and there may be other molecular mechanisms. High levels of catechin and ellagic acid in QMF can be developed as potential drugs to treat different types of cancer cells. PRACTICAL APPLICATIONS: Quercus species have been widely studied because of their antioxidant, anti-inflammatory, antimicrobial, and anti-tumor properties. Bioactive compounds in the leaves of Quercus mongolica Fisch have high levels of catechin and ellagic acid, which exert significant inhibitory properties on the proliferation of various types of cancer cells. Therefore, the bioactive compounds may be potential natural drugs in the prevention of cancer development and progression.

Cytotoxic Properties of C17 Polyacetylenes from the Fresh Roots of Panax ginseng on Human Epithelial Ovarian Cancer Cells.

Although C17 polyacetylenes from Panax ginseng exhibit cytotoxic properties against various tumor cells, there have been few experiments on epithelial ovarian carcinoma cells. This study aimed to investigate the cytotoxic effects of C17 polyacetylenes from P. ginseng against ovarian cancer cell lines. Four unreported (1–4) and fifteen known (5–19) C17 polyacetylenes were obtained from the roots of P. ginseng using repeated chromatography (open column, MPLC, and preparative HPLC). The chemical structures of all the compounds were determined by analyzing their spectroscopic data (NMR, IR, and optical rotation) and HR-MS. The structures of new polyacetylenes were elucidated as (3S,8S,9R,10R)-(-)-heptadeca-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (1), (3S,8S,9R,10R)-(−)-heptadeca-1-en-9,10-epoxy-4,6-diyne-3,8-diyl diacetate (2), (−)-haptadeca-9,10-epoxy-8-methoxy-4,6-diyne-3,11-diol (3), and (3R,9R,10R)-(+)-3-acetoxy-9,10-dihydroxyheptadeca-1-en-4,6-diyne (4), named ginsenoynes O, P, and Q, and 3-acetyl panaxytriol, respectively. Subsequently, in vitro experiments on A2780 and SKOV3 human epithelial ovarian carcinoma cells were performed to assess the cytotoxic properties of the isolates. Among the isolates, panaquinquecol 4 (15) exhibited the most remarkable cytotoxic effects on both human ovarian cancer cells A2780 (IC50 value of 7.60 μM) and SKOV3 (IC50 value of 27.53 μM). Therefore, C17 polyacetylenes derived from P. ginseng may warrant further investigation for their therapeutic potential in epithelial ovarian cancer.

Combination of melatonin with paclitaxel reduces the TLR4-mediated inflammatory pathway, PD-L1 levels, and survival of ovarian carcinoma cells

Ovarian cancer (OC) has a high mortality rate. Although most patients respond to the conventional chemotherapy [e.g., paclitaxel (PTX)], some also develop drug resistance to make the treatment less effective. Since melatonin exhibits antioxidant, antitumor, and immunomodulatory functions in a variety of solid tumors, in this study the effects of a combination of PTX and melatonin on SKOV-3 human ovarian carcinoma cells were investigated and the focus was given to the Toll-like receptor (TLR)-mediated inflammatory pathway and cell signaling-related molecules. Flow cytometry showed that this combination significantly boosted the apoptosis/necrosis responses of the cancer cells. Cell migration was attenuated by melatonin alone, and the combination led to a reduced number of migrating and invasive cells. Melatonin alone and its combination also reduced the levels of TLR4, MyD88, TRIF, and PD-L1, but not TLR2. In addition, the combination significantly lowered the levels of NF-kB p65, PI3K, p-AKT, p38, ERK 1/2, JNK, CREB, p70s6K, and STAT5. The results suggested that this combination was effective in reducing the viability and the invasive capacity of SKOV-3 cells while increasing their apoptosis and necrosis rates. The potential mechanism of this combination is to attenuate the downstream molecules of the TLR4-mediated inflammatory pathway and cell signaling-related proteins in the cancer cells. Thus, melatonin improved the chemosensitivity of the cancer cells to PTX, serving as an effective adjuvant therapy against OC.

Nickel Nanoparticles Originated from Cressa Leaf Extract in the Preparation of a Novel Melem@Ni-HPA Photocatalyst for the Synthesis of Some Chromenes and a Preliminary MTT Assay on the Anticancer Activity of the Nanocomposite

Organic photochemical synthesis with visible-light has attracted much attention in recent years by academia and industrial societies due to green features of this strategy. The present study mainly focuses on the preparation of Melem@Ni-HPA nanocomposite and application of this magnetic material as an efficient photocatalyst in the fabrication of different chromenes under simple and practical conditions. The target cromenes are prepared via condensation of coumarin, aromatic aldehyde and dimedone in an open-air condition by the help of a commercial green laser in acetonitrile. Then, the structural and morphological characteristics of this new nanophotocatalyst was evaluated by routine techniques such as X-Ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), dynamic light scattering (DRS), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and vibrating-sample magnetometry (VSM). Notable advantages of this new methodology include short reaction time, cost-effectiveness, facile separation of the catalyst by a magnet, excellent performance, and acceptable atom economy. A number of contributing experimental variables are also fully attended to unravel the broadness and generality of this method. In addition, progression of the reaction seems to proceed through a radical mechanism and suggest that reactive species like •O2 – and OH• along with h+ are implicated in the photocatalytic mechanism. Reusability and stability experiments also confirmed acceptable reproducibility of the nanophotocatalyst in at least five runs. Finally, the in-vitro cellular cytotoxicity of melem@Ni-HPA nanocomposite was tested against SKOV3 human ovarian carcinoma cell line via a preliminary MTT assay. The reduction in cell viability confirmed cytotoxicity of this nanomaterial on the selected cancer cell line.

Engineering the Synthesis of Luminescent Carbon Dots With Ultra High-Quantum Yield Using Experimental Design Approach in Order to Develop Sensing Applications

Carbon dots have been employed in a series of exciting fields such as bioimaging, drug delivery, fluorescent probing and analysis, photo-catalysis. Improving fluorescence performance of carbon dots could result in broadening their applications, especially, in sensing and bioimaging systems. The purpose of this study is to fabricate carbon dots by means of the hydrothermal method and designing an experiment in order to reach the highest quantum yield so as to develop their sensing and bioimaging applications. An experimental program was designed by taking into account factors effects on the quantum yield of carbon dots. The influencing variables to synthesize carbon dots in this project are citric acid concentration (F1), reaction temperature (F2), ethylenediamine concentration (F3) and reaction time (F4). By applying the experiment the quantum yield of carbon dots presents the maximum result of 85.69% at the optimal conditions of citric acid: 0.2 g, reaction temperature: 175°C, Ethylenediamine: $480~\mu \text{L}$ and reaction time: 4:43 h, which was the highest quantum yield from such carbon dots. These carbon dots have been applied as a fluorescence probe for Fe3+ ions determination with a perfect detection limit of 0.32 ppm. They were put to use for bioimaging of human ovarian carcinoma SKOV3 cells, which proved to be of outstanding biocompatibility.

Polysaccharides from Pyracantha fortuneana and its biological activity

This study used response surface methodology to determine the optimal conditions for extraction of polysaccharides from Pyracantha. fortuneana (PSPF), and studied the mechanism of PSPF-inducing apoptosis in human ovarian carcinoma Skov3 cells. Response surface methodology (RSM) were adopted to extract PSPF. The maximum value of polysaccharide yield was obtained under these optimal conditions. PSPF had good potential as an antioxidant. Exposure of cells to PSPF resulted in cytotoxicity through the induction of apoptosis, and the reactive oxygen species were increased, mitochondrial membrane potential decreased, DNA damage (detected as γ- H2AX and RAD51 foci) was observed in Skov3 cells. In addition, PSPF could induce apoptosis of cancer cells. Therefore, PSPF should be explored as novel potential antioxidants and an anti-tumor drug in a clinical setting.

Astaxanthin Combine with Human Serum Albumin to Abrogate Cell Proliferation, Migration, and Drug-resistant in Human Ovarian Carcinoma SKOV3 Cells.

Astaxanthin (AST) shows a large range of beneficial effects together with anti-cancer and antioxidation properties. Human Serum Albumin (HSA) is the most abundant protein in blood plasma which plays the role of a depot and transport protein for many exogenous compounds. However, whether HSA could enhance AST-induced cytotoxic effects in human ovarian cancer cells has not been examined to date. This study aims to explore the anticancer effect and the molecular mechanism of AST combine with HSA induced cytotoxicity in ovarian cancer SKOV3 cells. The ovarian cancer SKOV3 cells were treated by AST combined with HSA to study the effects of cell proliferation, cell morphology, cell cycle arrest, related protein expression, nuclear transfer, cell migration, and drug-resistant. Our data confirmed that AST+HSA treatment enhanced the anticancer effects of AST, arrested G1 phase cell cycle and induced apoptosis in SKOV3 cells. AST+HSA induced apoptosis via mitochondrial apoptotic pathways was related to the increased ratio of Bcl-2/Bax and activation of caspase-3. Besides, exposure of cells to AST+HSA triggered the inactivation of NF-κB and activation p53 and MAPKs signaling pathways. Furthermore, AST+HSA significantly overcome the drug-resistant and inhibited the migration of SKOV3 cells. AST combined treatment with HSA considerably inhibited NF-κB expression and translocation to nucleus, thereby improving the AST-induced cytotoxic effect on SKOV3 cells. These findings may provide rationale to combine AST with HSA for the treatment of ovarian cancer.

Expression profile and prognostic value of SFN in human ovarian cancer.

Ovarian cancer is a highly lethal cancer in females. Therefore, it is necessary to explore effective biomarkers for the diagnosis and prognosis of the disease. Stratifin (SFN) is a cell cycle checkpoint protein that has been reported to be involved in oncogenesis. Our studies detected the expression of SFN in ovarian cancer by Oncomine, Human Protein Atlas database and ULCAN database. Meanwhile, we found its coexpression gene by cBioPortal online tool and validated their expression in different ovarian cancer cells by western blot and reverse transcription quantitative PCR. Then, we also investigated their prognostic values via the Kaplan–Meier plotter database in different subtypes of ovarian cancer patients. The results demonstrated that SFN was found to be increased in ten various ovarian cancer datasets, compared with healthy tissues. Additionally, up-regulation of SFN expression is associated with age and cancer grades. The higher expression of SFN in all patients with ovarian cancers is significantly correlated with worse postprogression survival. In addition, high SFN expression is associated with significantly worse overall survival in patients who received chemotherapy contains gemcitabine, taxol, taxol+platin, paclitaxel and avastin. In human ovarian carcinoma SKOV3 and A2780 cells, the expression of SFN and its coexpression gene MICB were also increased at protein and mRNA levels compared with the normal ovarian epithelial cells. Based on above results, overexpression of SFN was correlated with the prognosis in ovarian cancer. The present study might be useful for better understanding the clinical significance of SFN mRNA.

Enhanced anti-proliferative and pro-apoptotic effects of metformin encapsulated PLGA-PEG nanoparticles on SKOV3 human ovarian carcinoma cells

Metformin (MET) has received considerable attention in recent years for its anticancer potential activities. However, short half-life and weak bioavailability of MET limited its use as a chemotherapeutic agent. The present study is intended to evaluate the efficiency of PLGA-PEG as a nano-carrier for MET to increase anticancer effects on SKOV3 ovarian carcinoma cells. MET-loaded PLGA-PEG nanoparticles (NPs) were characterized through Dynamic Light Scattering (DLS), Fourier-transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FE-SEM). Anti-proliferative and apoptotic effects of nanoformulated MET were evaluated using MTT and flow-cytometric assays, respectively. Also, real-time polymerase chain reaction (Real-Time PCR) was used to determine the gene expression levels of apoptotic genes, p53 and hTERT. Evaluation of cytotoxicity showed that MET-NPs had more cytotoxicity than free MET in a time-and dose-dependent manner. The nuclei fragmentation and the percentage of apoptotic cells induced by MET-NPs were significantly higher than free MET. Also, it was found that MET-NPs triggered more cell cycle arrest at sub-G1 checkpoint than free MET. Compared to MET treated cells, the mRNA expression levels of apoptotic genes, as well as p53 and hTERT were significantly altered in MET-NPs treated cells. In conclusion, it is supposed that nano-encapsulation of MET into polymeric PLGA-PEG NPs may be a convenient drug delivery system to enhance its anticancer effects for ovarian cancer therapy.

Induction of autophagic cell death in human ovarian carcinoma cells by Antrodia salmonea through increased reactive oxygen species generation.

We reported in our previously executed studies that the fermented culture broth of Antrodia salmonea (AS), a mushroom used in Taiwanese folk medicine induced reactive oxygen species (ROS)-mediated apoptosis in human ovarian carcinoma cells. In this study, we studied the anticancer efficacies of AS (0-240 μg/ml) by examining the key molecular events implicated in cell death associated with autophagy in SKOV-3 and A2780 human ovarian carcinoma cells and clarified the fundamental molecular mechanisms. Treatment of ovarian carcinoma cells with AS-induced autophagic cell death mediated by increased microtubule-associated protein LC3-II, GFP-LC3 puncta, and acidic vesicular organelle (AVO) formation. These events are linked with the activation of p62/SQSTM1, the inhibition of ATG4B, the expression of ATG7, and the dysregulation of Beclin-1/Bcl-2 (i.e., B-cell lymphoma 2). N-acetylcysteine inhibited AS-induced ROS generation, which in turn constricted AS-induced LC3 conversion, AVO formation, and ATG4B inhibition, indicating ROS-mediated autophagy cell death. In addition, the 3-methyladenine (3-MA) or chloroquine (CQ)-induced autophagy inhibition decreased AS-induced apoptosis. Additionally, apoptosis inhibition by Z-VAD-FMK, a pan-caspase inhibitor, substantially suppressed AS-induced autophagy. Furthermore, AS-inhibited HER-2/ neu and PI3K/AKT signaling pathways which were reversed by autophagy inhibitors 3-MA and CQ. Thus, A. salmonea is a potential chemopreventive agent that is capable of activating ROS-mediated autophagic cell death in ovarian carcinoma cells.

Oncobox Bioinformatical Platform for Selecting Potentially Effective Combinations of Target Cancer Drugs Using High-Throughput Gene Expression Data.

Sequential courses of anticancer target therapy lead to selection of drug-resistant cells, which results in continuous decrease of clinical response. Here we present a new approach for predicting effective combinations of target drugs, which act in a synergistic manner. Synergistic combinations of drugs may prevent or postpone acquired resistance, thus increasing treatment efficiency. We cultured human ovarian carcinoma SKOV-3 and neuroblastoma NGP-127 cancer cell lines in the presence of Tyrosine Kinase Inhibitors (Pazopanib, Sorafenib, and Sunitinib) and Rapalogues (Temsirolimus and Everolimus) for four months and obtained cell lines demonstrating increased drug resistance. We investigated gene expression profiles of intact and resistant cells by microarrays and analyzed alterations in 378 cancer-related signaling pathways using the bioinformatical platform Oncobox. This revealed numerous pathways linked with development of drug resistant phenotypes. Our approach is based on targeting proteins involved in as many as possible signaling pathways upregulated in resistant cells. We tested 13 combinations of drugs and/or selective inhibitors predicted by Oncobox and 10 random combinations. Synergy scores for Oncobox predictions were significantly higher than for randomly selected drug combinations. Thus, the proposed approach significantly outperforms random selection of drugs and can be adopted to enhance discovery of new synergistic combinations of anticancer target drugs.

Preparation of Folic Acid-Targeted Temperature-Sensitive Magnetoliposomes and their Antitumor Effects In Vitro and In Vivo.

Ovarian cancer is a common gynecologic malignancy with poor prognosis, requiring innovative new therapeutic strategies. Temperature-controlled drug delivery to cancer cells represents a novel, promising, targeted treatment approach. We prepared folate receptor-targeted thermosensitive liposomes wrapped with the HSP90 inhibitor 17-AAG and superparamagnetic material (17-AAG/MTSLs-FA), and tested the efficacy of these targeted magnetoliposomes in vitro and in vivo. Magnetic thermosensitive liposomes wrapped with 17-AAG were coprecipitated with Fe3O4 magnetic nanoparticles and prepared by a rotary evaporation method. Experiments were conducted with SKOV3 human ovarian cancer cells and MCF7 human breast carcinoma cells to evaluate the anti-tumor effects. 17-AAG/MTSLs-FA prepared in this study met the basic requirements for therapeutic application. The preparation method is relatively simple and the raw materials are readily available. The product exhibited strong magnetism, high encapsulation efficiencies, and satisfactory performance. The liposomes combined with hyperthermia significantly inhibited the proliferation of SKOV3 cells and induced apoptosis. Experiments using a mouse subcutaneous model as well as an ascites tumor xenograft model indicated that 17-AAG/MTSLs-FA was stable in vivo and effectively targeted tumor tissues expressing the folate receptor. Folic acid-conjugated 17-AAG magnetic thermosensitive liposomes in combination with an alternating magnetic field for heating can achieve a synergistic anti-tumor effect of chemotherapy and heat treatment, potentially offering a new method for ovarian cancer treatment.

1,2,3-Triazole Tagged 3H-Pyrano[2,3-d]pyrimidine-6-carboxylate Derivatives: Synthesis, in Vitro Cytotoxicity, Molecular Docking and DNA Interaction Studies.

A series of novel ethyl 2,7-dimethyl-4-oxo-3-[(1-phenyl-1H-1,2,3-triazol-4-yl)methyl]-4,5-dihydro-3H-pyrano[2,3-d]pyrimidine-6-carboxylate derivatives 7a - 7m were efficiently synthesized employing click chemistry approach and evaluated for in vitro cytotoxic activity against four tumor cell lines: A549 (human lung adenocarcinoma cell line), HepG2 (human hematoma), MCF-7 (human breast adenocarcinoma), and SKOV3 (human ovarian carcinoma cell line). Among the compounds tested, the compounds 7a, 7b, 7f, 7l, and 7m have shown potential and selective activity against human lung adenocarcinoma cell line (A549) with IC50 ranging from 0.69 to 6.74 μm. Molecular docking studies revealed that the compounds 7a, 7b, 7f, 7l, and 7m are potent inhibitors of human DNA topoisomerase-II and also showed compliance with stranded parameters of drug likeness. The calculated binding constants, kb , from UV/VIS absorptional binding studies of 7a and 7l with CT-DNA were 10.77 × 104 , 6.48 × 104 , respectively. Viscosity measurements revealed that the binding could be surface binding mainly due to groove binding. DNA cleavage study showed that 7a and 7l have the potential to cleave pBR322 plasmid DNA without any external agents.

P-17 - Expression of genes encoding NΑΔΗ−oxidase 5 and key antioxidant enzymes under formation of cancer cell resistance to cisplatin

The important role in the maintenance of redox homeostasis is played by the ratio of ROS generation and catabolism catalyzed by enzymes whose imbalance can lead to an increase in the intracellular level of ROS and the development of some pathologies including cancer. Here we studied expression of genes, which involve in the control of the cellular redox state, under the development of resistance of human ovarian carcinoma SKOV-3 cell to cisplatin; its cytostatic effect is associated in a great part with prooxidant effect. It was found that the formation of cancer cell resistance was accompanied by an increase in the expression of genes encoding key antioxidant enzymes (SOD2, CAT, GPX1, HO-1) in parallel with a significant decrease in expression of the NOX5 gene, which controls one of major sources of ROS. The coordinated character of changes in the expression of genes can be promoted by enhanced expression of transcription factor Nrf2 in addition with the growth of GSH/GSSG ratio. The obtained results testify to the redox-dependent development of the adaptive antioxidant response as an important process in the mechanism of formation of cancer cell resistance to cisplatin. Acknowledgements: The publication was prepared with the support of the “RUDN University Program 5–100”.

P-304 - Glutathione in redox regulation of the development of cancer cell resistance

The ratio of reduced glutathione to its oxidized form (GSH/GSSG) is essential for cell viability including its role in redox-dependent regulation of gene expression. The aim of our study was to estimate GSH/GSSG ratio and expression of redox-dependent genes (glutaredoxin, thioredoxin, peroxiredoxin) under development of cancer cell resistance to cisplatin (CDDP) possessed pro-oxidant action. Under development of resistance of human erythroleukemia K562 and ovarian carcinoma SKOV-3 cells to CDDP co-ordinative enhanced expression of genes encoding glutathione synthetase (GS), subunits of γ-glutamylcysteine synthetase (γ-GCSH, γ-GCSL) was found. In addition, the growth of GSH/GSSG, enhanced expression of glutaredoxin (GLRX1, GLRX2), thioredoxin (TRX2), peroxiredoxin (PRDX6) genes as well as elevated level of transcription factor Nrf2 were observed in both types of resistant cells. We suggest that mechanism of development of cancer cell resistance to CDDP can include activation of GSH synthesis de novo, redox-dependent increase in expression of GLRX1, GLRX2, TRX2, PRDX6 genes which are co-ordinative regulated by redox-dependent transcription factor Nrf2 and elevated level of GSH/GSSG. The publication was prepared with the support of the “RUDN University Program 5–100”.

Two new β-carboline alkaloids from the stems of Picrasma quassioides.

Two new β-carboline alkaloids, 1-acetyl-4-methoxy-8-hydroxy-β-carboline (1) and 1-acetyl-4,8-dimethoxy-β-carboline (2), together with 10 known compounds; seven β-carboline alkaloids (3-9), two canthin-6-one alkaloids (10 and 11), and one quassinoid (12) were isolated from the stems of Picrasma quassioides. The structure of the new compounds 1 and 2 were determined by spectroscopic analyses including 1D- and 2D-NMR and HRMS interpretation. All the isolates (1-12) were evaluated for their cytotoxicity against human ovarian carcinoma A2780 and SKOV3 cell lines using MTT assays. Of the isolates, compounds 5-7 exhibited the most potent cytotoxicity on both A2780 and SKOV3 cell lines in vitro.

Folate-decorated and NIR-activated nanoparticles based on platinum(IV) prodrugs for targeted therapy of ovarian cancer

Platinum-based drugs are used to treat a variety of cancers but have many side effects such as nephrotoxicity and neurotoxicity. A folate-decorated nanoparticles system with a good drug payload can selectively deliver drugs into folate receptor (FR)-overexpressing cancer cells to prevent the shortcomings of platinum-based chemotherapy. Here, folate-decorated and near-infrared (NIR) laser-activated nanoparticles (abbreviated as PtIV-FINPs) were prepared via ultrasonic self-assembling of platinum(IV) prodrug c,c,t-Pt(NH3)2Cl2(OOCCH2CH2COOH)2, folic acid (FA)-functionalized lipid DSPE-PEG-FA and NIR fluorescent dye indocyanine green (ICG). The obtained PtIV-FINPs had almost spherical shape with a mean diameter about 100 nm. In vitro cellular uptake, cytotoxicity assays revealed that upon NIR irradiation, PtIV-FINPs further enhanced cellular uptake and generated higher cytotoxicity against human ovarian carcinoma SKOV3 cells than non-targeted or non-NIR activated nanoparticles. Thus, the multifunctional nanoparticles have potential to be developed as an attractive drug delivery system for effective chemotherapy against FR-overexpressing cells.

MicroRNA-340 induces apoptosis by downregulation of BAG3 in ovarian cancer SKOV3 cells.

Aberrant expression of miR-340 has been found in several kinds of cancers including ovarian cancer. Pro-apoptotic and anti-metastasis roles of miR-340 in ovarian cancer have also been reported; however, the underling molecular mechanisms by which miR-340 suppresses ovarian cancer are still unclear. This study focused on the role and molecular mechanism of miR-340 in ovarian cancer. Human ovarian carcinoma SKOV3 cells were used and transfected with miR-340 mimic, miR-340 inhibitor and their correspondingly negative controls (mimic control and inhibitor control). Thereafter, cell viability, apoptosis, and the expressions of apoptosis-associated factors and BAG3 were respectively assessed by MTT assay, flow cytometry, qRT-PCR and Western blotting. SKOV3 cells were then co-transfected with miR-340 inhibitor and BAG3 targeted siRNA, then cell viability, apoptosis and the expression of apoptosis-associated factors were retested. Besides, the expressions of main factors in PI3K/AKT pathway were detected. Overexpression of miR-340 suppressed BAG3 cells viability (P < 0.05), but improved apoptosis (P < 0.001). BAG3 was negatively regulated by miR-340 (P < 0.05 or P < 0.01). BAG3 silence significantly induced cell apoptosis (P < 0.001), and abolished miR-340 suppression-induced increase in cell viability (P < 0.001). Besides, BAG3 silence abolished miR-340 suppression-induced activation of PI3K and AKT. This study revealed the tumor suppressive role of miR-340 in SKOV3 cells by negative regulation of BAG3. PI3K/AKT pathway might be involved in the regulation of miR-340 and BAG3.

P 092 - Coordinated alteration of expression of redox-dependent genes in development of adaptive antioxidant response under formation of drug resistance of cancer cells

Aims Here we studied the expression of isoforms of redox-dependent antioxidant enzymes and a rise of adaptive antioxidant response under development of cancer cells resistance to anticancer agent cisplatin (CDDP) possessed pro-oxidant action. Results Under development of resistance of human erythroleukemia K562 and ovarian carcinoma SKOV-3 cells to CDDP co-ordinative enhanced expression of genes encoding isoforms of superoxide dismutase (SOD1, SOD2), glutathione peroxidase (GPx1, GPx4), glutathione transferase (GSTP1-1, GSTМ1-1), glutaredoxin (GLRX1, GLRX2), thioredoxin (TRX1,TRX2) was found in both types of resistant cells in compare with wild cells. In addition, growth of GSH/GSSG ratio as index of cellular redox state as well as elevated level of transcription factor Nrf2 were observed in resistant K562/DOX and SKVLB cells. Decrease of apoptotic cell death was observed under exposure to hydrogen peroxide in the CDDP-resistant cells possessed elevated antioxidant status, as evidenced by low generation of ROS. It can be concluded that the mechanism of the formation of cancer cells resistance to CDDP involves the development of adaptive antioxidant response as key in stress adaptation.