Hatice Mehtap Kutlu

Promising anti-growth effects of palladium(II) saccharinate complex of terpyridine by inducing apoptosis on transformed fibroblasts in vitro.

Fibrosarcoma is one of the fatal cancer types and there is still not satisfactory success in its treatment despite new drugs. Therefore, the search for a new compound has been going on. It is currently known that some palladium-based anti-cancer compounds seem to have powerful apoptosis-inducing effects in cancer cells. For this purpose, a palladium(II)-saccharinate complex containing terpyridine which was synthesized by our research group was investigated in terms of its anti-tumor effects against mouse embryonic fibroblast NIH/3T3 (normal cell line) and rat embryonic fibroblast 5RP7 (H-ras transformed cell line) in vitro. The MTT and ATP viability assays were used to determine anti-growth/cytotoxic effects. Cytotoxic activity was confirmed by real time cytotoxicity analysis system. Flow cytometry analysis was further used to determine the mode of cell death (apoptosis/necrosis). Apoptosis was confirmed by triple-staining the cells with Hoechst 33342/PI/Calcein-AM triple and evaluated with fluorescence microscopy. It was found that the compound showed significant anti-growth activity by inducing apoptosis in a dose dependent manner. In conclusion, taking into account the cytotoxic activity of the compound at even relatively lower doses, in vivo experiments to elucidate its potential use for the treatment of fibrosarcoma are warranted.

Isolation and identification of selenite reducing archaea from Tuz (salt) Lake In Turkey

In this study, Tuz lake brine samples were investigated for isolation and identification of selenite resistant halophilic prokaryotes. Among the 20 strains of extremely halophilic Bacteria and Archaea, a Gram negative rod designated as strain 106, showed high capacity in the resistance to selenite (25 mM) under aerobic conditions. Phenotypic characterizations and phylogenetic analyses based on 16S rDNA sequence comparison indicated that strain 106 was Halorubrum xinjiangense. The ability of strain 106 to deposite selenium‐containing particles were investigated by Transmission Electron Microscopy (TEM). Electron micrographs shows intact cells after selenite reduction and large amounts of selenium‐containing particles are present in the culture medium indicating that strain 106 is able to efficiently transport elemental selenium out of the cell.

Examining impacts of ceranib-2 on the proliferation, morphology and ultrastructure of human breast cancer cells

Acid ceramidases are enzymes with a vital role in metabolizing ceramide to sphingosine-1-phosphate that is an antiproliferative metabolite in the ceramide pathway. Inhibition of exogenous ceramides with ceramidase inhibitors lead to augmented ceramide levels in cells and in turn lead to cell cycle arrest and apoptosis. Our study aimed at targeting ceramide metabolic pathway to induce apoptosis in human breast cancer cell line (MCF7) and we examined the antiproliferative and apoptotic activities of ceranib-2, an inhibitor of human ceramidase, on this cell line as well ultrastructural and mophological changes. Methods used for our examinations in this study were the colorimetric MTT assay, Annexin V/Propidium iodide and JC-1 staining, transmission electron microscopy and confocal microscopy. Ceranib-2 effectively inhibited the viability of MCF7 cells in 24 h in a dose dependent manner leading to apoptosis via the mitochondrial pathway by reducing the potential of mitochondrial membrane. Additionally, significant changes on cell morphology and ultrastructure were observed on MCF7 cells exposed to ceranib-2 indicating apoptotic cell death. Collectively, our data demonstrate that ceranib-2 exerts a great potential to be an antineoplastic compound and that the mechanism of its action rely on its apoptosis inducing ability.

Acrylamide-derived cytotoxic, anti-proliferative, and apoptotic effects on A549 cells

Background: Acrylamide is a very common compound even reaching up to our daily foods. It has been studied in a wealth of cell lines on which it proved to have various toxic effects. Among these cell lines, human lung adenocarcinoma cell line (A549) is one of that on which acrylamide’s toxicity has not been studied well yet. Aim: We intended to determine the half maximal inhibitory concentration (IC50) dose of acrylamide and to investigate its cytotoxic, anti-proliferative and apoptotic effects on A549 cells. Methods: We determined the IC50 dose by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Then, the mode of cell death was evaluated by flow cytometry using Annexin-V fluorescein isothiocyanate (FITC)/propidium iodide (PI) staining. Next, we performed transmission electron microscopy (TEM) and confocal microscopy analyses for morphological alterations and apoptotic indices. Results: According to the MTT assay results, A549 cell viability decreases proportionally with increasing acrylamide concentrations and IC50 for A549 was 4.6 mM for 24 h. Annexin-V FITC/PI assay results indicated that acrylamide induces apoptosis in 64% of the A549 cells. TEM and confocal microscopy analyses showed nuclear condensations, fragmentations, cytoskeleton laceration, and membrane blebbing, which are morphological characteristics of apoptosis. Conclusion: Our research suggests that acrylamide causes cytotoxic, anti-proliferative, and apoptotic effects on A549 cells at 4.6 mM IC50 dose in 24 h.

Acrylamide exerts its cytotoxicity in NIH/3T3 fibroblast cells by apoptosis

Objective: Acrylamide is a chemical utilized in various industries, and many studies have demonstrated its toxicity. The NIH/3T3 mouse embryonic cell line is the standard cell line of fibroblasts, which have a pivotal role with their versatile functions in the body. However, only two studies have attempted to investigate the effect of acrylamide on these crucial cells. To fill this knowledge gap, we aimed to determine the effects of acrylamide on NIH/3T3 cells. Method: First, we performed the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide assay and calculated the IC50 dose of acrylamide. Then, we treated cells with the IC50 dose of acrylamide for 24 h and determined whether the dominant death mode of NIH/3T3 cells was apoptosis or necrosis by annexin V and caspase 3/7 assays. Finally, we performed confocal microscopy and transmission electron microscope (TEM) analysis for observing the morphological alterations. Results: MTT assay results showed that acrylamide treatment reduced the viability of NIH/3T3 cells dose-dependently and that the IC50 of acrylamide was 6.73 mM. Based on annexin V and caspase 3/7 assays, the dominant death mode of NIH/3T3 cells was determined to be apoptosis. Also, caspase 3/7 activities of the acrylamide-treated NIH/3T3 cells were three times greater than those of the untreated NIH/3T3 cells. Furthermore, we observed membrane blebbing, nuclear chromatin clumping, and cytoplasmic vacuolization in TEM analysis and apparent apoptotic bodies, nuclear fragmentations, and condensations in confocal microscopy. Conclusions: In conclusion, our results suggested that the IC50 of acrylamide against NIH/3T3 cells for 24 h was 6.73 mM and that acrylamide exerted its cytotoxic and anti-proliferative effects on these cells mainly via apoptosis.

The apoptotic and genomic studies on A549 cell line induced by silver nitrate

Lung cancer is the leading cause of male cancer deaths worldwide. Metal-based anticancer drugs have evolved significantly during the past decades. Recently, silver ions have been investigated for their anticancer effects. We aimed to study the time-course cytotoxic effects of silver nitrate on A549 adenocarcinomic human alveolar basal epithelial cells to provide insights into the molecular-level understanding of growth suppression mechanism involved in apoptosis. The influences of silver nitrate were studied via MTT assay, flow cytometry, immunocytochemical, confocal and transmission electron microscopy, and microarray assays. Silver nitrate showed inhibitory effects against A549 cells in a dose- and time-dependent manner for 24, 48, and 72 h and induced apoptosis. The early and late apoptotic cells and depolarized mitochondrial membrane potential were determined by the half-maximal inhibitory concentration (IC50) value of silver nitrate treated for 72 h. But cysteinyl aspartate proteinase-3 was not activated for 72 h. Furthermore, IC50 value of silver nitrate also induced apoptosis according to immunocytochemical assays for 72 h. The downregulated CCNY, HNRNPL, ASF1B, PIAS4, HNRNPH1, EIF2C2, TAF15, FOXC1, LEP, and PCB2 genes administered with silver nitrate IC50 were identified as apoptosis-leading genes. Silver nitrate may be a suitable therapeutic agent against lung cancer.

Antiproliferative and Apoptotic Effects of Vanadyl Sulphate on H-Ras Transformed 5rp7 Cells

Metal based drugs have successfully been used in the detection and treatment of a variety of diseases [1]. Despite the advantages in early diagnostic and treatment of cancer, there is essential to develop new alternative of drugs. A number of in vitro studies have revealed that vanadium shows its antitumor effects on various cell lines [2]. Moreover, it is shown that vanadium compounds may show cytotoxic effects through DNA cleavage and fragmentation, in vitro [3]. According to these studies, here in we aimed to investigate the cytotoxic and antiproliferative effect of vanadyl sulphate in vitro, also to detect the effect of this agent on H-Ras transformed 5RP7 cells ultrastructure.