Ayşe Tansu Koparal

Assessment of anti-angiogenic and anti-tumoral potentials of Origanum onites L. essential oil

Medicinal plants and culinary herbs with anti-angiogenic and little toxicity properties have gained importance. Non-toxic anti-angiogenic phytochemicals are useful in combating cancer by preventing the formation of new blood vessels to support the tumor growth. We have investigated the essential oil of Origanum onites L. (OOEO), for a possible anti-angiogenic activity. OOEO was analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). The anti-proliferative activities (by MTT assay, 3-(4,5-dimethyl-2-thiazol)-2,5-diphenyl-2H-tetrazolium bromide), anti-angiogenic activities (by tube formation assay), cell migration inhibiting capability (migration assay) and apoptotic potential (DAPI staining) of OOEO were evaluated on rat adipose tissue endothelial cells (RATECs) and 5RP7 (c-H-ras transformed rat embryonic fibroblasts) cells. Our results revealed that OOEO could markedly inhibit cell viability and induced apoptosis of 5RP7 cells and also could block in vitro tube formation and migration of RATEC. These results imply that OOEO having anti-angiogenic activity might be useful in preventing angiogenesis-related diseases and in combating cancer.

Novel ferrocenyl-containing N-acetyl-2-pyrazolines inhibit in vitro angiogenesis and human lung cancer growth by interfering with F-actin stress fiber polimeryzation

Abstract Cancer is a significant worldwide health problem generally because of lack of widespread and comprehensive early detection methods. Lung cancer is the leading cause of cancer deaths in men worldwide and the second leading cause of cancer deaths in women. To date, the available treatment regimens are not successful. For this reason, new targets for prevention and new agents for therapy need to be identified. The biological activities of some synthesized ferrocene-containing N-acetylated-2-pyrazoline compounds were studied for this article. Their cytotoxicity (by methyl thiazol tetrazolium assay), as well as apoptotic (by 4′6-diamidino-phenylindole and F-actin staining), antitumoral (colony-forming ability assay) and antiangiogenic activities (by tube formation), were evaluated for the first time on a human non-small-cell lung cancer (A549) cell line and a human umbilicial vein endothelial cell line. All compounds were cytotoxic, antitumoral and apoptotic against tumor cells in a dose-dependent manner. Compounds 2 and 3, which were noncytotoxic, could inhibit capillary vessel formation. Especially, N-acetyl-5-ferrocenyl-3-(2-thienyl)-2-pyrazoline (2) may be used in the development of therapeutic agents for angiogenic diseases and cancer.

Cryptic fragment α4 LG4-5 derived from laminin α4 chain inhibits de novo adipogenesis by modulating the effect of fibroblast growth factor-2

Cleavage of the extracellular matrix (ECM) by proteolysis unmasks cryptic sites and generates novel fragments with biological activities functionally distinct from those of the intact ECM molecule. The laminin G‐like (LG)4‐5 fragment has been shown to be excised from the laminin α4 chain in various tissues. However, the functional role of this fragment has remained unknown to date. To investigate this, we prepared α4 LG1‐3 and α4 LG4‐5 fragments by elastase digestion of recombinant α4 LG1‐5, and examined their effects on de novo adipogenesis in mice at the site of injection of basement membrane extract (Matrigel) and fibroblast growth factor (FGF)‐2. Although the addition of whole α4 LG1‐5 suppressed adipogenesis to some extent, the α4 LG4‐5 fragment could strongly suppress adipogenesis at a concentration of less than 20 nm. Addition of the α4 LG4 module, which contains a heparin‐binding region, had a suppressive effect, but this was lost in mutants with reduced heparin‐binding activity. In addition, antibodies against the extracellular domain of syndecan‐2 and ‐4, which are known receptors for the α4 LG4 module, suppressed adipogenesis. Thus, these results suggest that the cryptic α4 LG4‐5 fragment derived from the laminin α4 chain inhibits de novo adipogenesis by modulating the effect of FGF‐2 through syndecans.

Induction of apoptosis and inhibition of cell proliferation by the cyclooxgenase enzyme blocker nimesulide in the Ishikawa endometrial cancer cell line

OBJECTIVES Endometrial cancer remains a leading cause of death in women and therefore the development of new therapies is essential. The present study evaluated the effects of nimesulide alone, cisplatin alone, and combination of cisplatin and nimesulide on an Ishikawa cell line with respect to cytotoxicity and induction of apoptosis in vitro. STUDY DESIGN Ishikawa cells were treated with increasing doses of nimesulide alone, cisplatin alone, and a combination of cisplatin and nimesulide. Subsequently their effects on cytotoxicity were investigated by MTT assay, while apoptosis was investigated by DAPI and JC-1 staining and caspase-3 colorimetric assays. RESULTS 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that nimesulide alone and combination of cisplatin and nimesulide have growth inhibitory effect on Ishikawa cells. Nimesulide alone and the combination of cisplatin and nimesulide induced apoptosis. Apoptosis induced by nimesulide might be related to caspase-3 activation. CONCLUSIONS These results suggest that nimesulide treatment is as effective as cisplatin treatment in Ishikawa cells. The combination of cisplatin and nimesulide treatment is more effective than cisplatin alone in Ishikawa cells.

Photoprotective Activity of Vulpinic and Gyrophoric Acids Toward Ultraviolet B‐Induced Damage in Human Keratinocytes

Vulpinic and gyrophoric acids are known as ultraviolet filters for natural lichen populations because of their chemical structures. However, to the best of our knowledge, there has been no reference to their cosmetic potential for skin protection against ultraviolet B (UVB)‐induced damage and, consequently, we propose to highlight their photoprotective profiles in human keratinocytes (HaCaT). Therefore, vulpinic acid and gyrophoric acid were isolated from acetone extracts of Letharia vulpina and Xanthoparmelia pokornyi, respectively. Their photoprotective activities on irradiated HaCaT cells and destructive effects on non‐irradiated HaCaT cells were compared through in vitro experimentation: 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide and lactate dehydrogenase assays, 4′,6‐diamino‐2‐phenylindole and tetramethylrhodamine B isothiocyanate‐phalloidin staining protocols. Both of the lichen substances effectively prevented cytotoxic, apoptotic and cytoskeleton alterative activities of 2.5 J/cm2 UVB in a dose‐dependent manner. Moreover, vulpinic and gyrophoric acids showed no toxic, apoptotic or cytoskeleton alterative effects on non‐irradiated HaCaT cells, except at high doses (≥400 μM) of gyrophoric acid. The findings suggest that vulpinic and gyrophoric acids can be promising cosmetic ingredients to photo‐protect human skin cells and should therefore be further investigated by in vitro and in vivo multiple bioassays. Copyright

Studies on the cytotoxic, apoptotic and antitumoral effects of Au(III) and Pt(II) complexes of 1, 10-phenanthroline on V79 379A and A549 cell lines

In the present study, Au(III) and Pt(II) complexes of 1, 10-phenanthroline (phen) were synthesized and used as the test compounds. The structure elucidation of the synthesized compounds was performed by IR, 1H-NMR and MASS spectroscopic data and the results of elemental analyses. The cytotoxic and apoptotic effects of test compounds were elucidated on V79 379A (Chinese hamster lung fibroblast like) and A549 (human lung carcinoma epithelial like) cell lines. Cytotoxicity was measured with MTT assay and antitumoral effect was determined by colony forming ability methods. In addition, nuclear fragmentation and activation of apoptotic enzyme (caspase-3) and DAPI staining were used to detect the apoptotic effect of the compounds. All the test compounds induced time and concentration-dependent cytotoxic and antitumoral effects. Significant increases in the levels of apoptosis were observed with increasing exposure concentration.

Resveratrol reduces IL-6 and VEGF secretion from co-cultured A549 lung cancer cells and adipose-derived mesenchymal stem cells

Stem cell therapies are important treatment methodologies used in many areas of experimental or clinical medicine. In recent studies of cancer models, Mesenchymal stem cells (MSCs) suppressed the growth of cancer cells. However, also in some studies, stem cell treatments have been shown to induce cancer formation, increase tumor volume, induce the formation of new vessels, and lead to cancer invasion. The presence of MSC-secreted cytokines and their effects on cancer cells limits the reliability of MSC-based treatments. Resveratrol (trans-3,5,4′-trihydroxystilbene), an antioxidant found in red wine, has been shown to have therapeutic effects against several cancers. The aim of this study was to co-culture MSCs with A549 cancer cells to suppress the release of cancer-promoting cytokines from MSCs and to increase the applicability and reliability of stem cell therapies with resveratrol. MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) and neutral red cell viability assays were used to find safety dose of resveratrol. The MSCs secreted the cytokines IL-6 and VEGF, and the effect of resveratrol on these cytokines was analyzed by ELISA and western blot analysis of conditioned medium. One μM of resveratrol was found to be the safety dose for the A549 cancer cells and MSCs. We observed the highest release of IL-6 and VEGF from the co-cultured A549 cells and MSCs, and resveratrol was found to significantly decrease the release of these cytokines. Our study suggests that resveratrol exerts a positive effect on the release of cytokines. The safety dose of resveratrol can be administered together with stem cells during stem cell treatment.

Gold(III) compounds-mediated inhibition of lung cancer cell proliferation.

Research on chemotherapeutics for lung cancer is crucial for designing a new therapeutic strategy against malignant lung tumors. Although radiotherapy and chemotherapy, which are not selective for cancer cells and exert toxic effects on healthy cells, have a limited advantage, they are the primary treatment modalities for non-small lung cancer. In addition to cytotoxicity, resistance of chemotherapeutics results in failure of treatment. This is why it is of utmost importance to focus on the creation of new chemotherapeutics without toxicity for the successful treatment and improved survival of cancer patients. New gold(III) and Pt(II) compounds were synthesized with a heterocyclic ligand using 2-phenylimidazo[4,5-f][1,10]phenanthroline as a ligand and bis-1,4-di[([1,10] phenanthroline-5-il)amino]-2-buten as a bridge molecule. The characterization of the compounds was carried out using a variety of spectroscopic methods (1H NMR, IR, MS, and elemental analysis). Their antiproliferative, antitumoral, and apoptotic activities were determined. IR spectra and NMR results confirmed the formation of dinuclear heterocyclic complexes for two metal complexes. Cytotoxicity studies on lung cancer cells (A549) and healthy cells (CHL) showed a marked increase in cytotoxicity with the use of gold(III) complexes, and especially [Au(L)B](PF6)2 showed higher cytotoxic and apoptotic features than cisplatin at lower concentrations in cancer cells. These findings have been supported by results from DAPI staining and colorimetric measurement of the caspase-3 enzyme in both cell lines. Compounds showed selective toxicity on the cancer cells. In the light of the high efficacy of our newly synthesized gold complexes, they might be good and promising anticancer agents compared with cisplatin.

Evaluation of Multifunctional Hybrid Analogs for Stilbenes, Chalcones and Flavanones

AIMS In this study, discovery of novel anticancer agents acting by more than one mechanism was aimed. METHOD For this purpose, eleven previously synthesized simple-stilbene, chalcone, flavanone derivatives and 31 novel stilbene-fused chalcones and stilbene-fused flavanones were tested for their aromatase inhibition, antiangiogenic and anti-proliferative properties in cancer (PC3, MCF-7) and healthy (HUVEC) cell lines. MTT cell viability assay was used to evaluate the anti-proliferative activities of the compounds. CYP19/MFC highthroughput screening kit (BD Biosciences, Oxford, UK) was used to search the aromatase inhibition properties and matrigel tube formation assay was applied to determine the anti-angiogenic activities. RESULTS Results indicate that the simple-chalcone and flavanone derivatives were more cytotoxic than the simple- stilbenes in the both cancer cell lines. In contrast, the simple-stilbene structures were much more effective at aromatase inhibition. The cytotoxicity profiles of stilbene-fused chalcones in cancer cells imply that these molecules mostly mimic the simple chalcone structures. On the other hand, flavanones lose their cytotoxic activities after becoming fused with stilbenes. Additionally, aromatase inhibition assays showed that stilbene-fused chalcones again do mimic the simple-chalcones but not simple-stilbenes and anti-angiogenic profiles of the tested molecules seem to be not related with stilbene fragments. Furthermore, stilbene-fused flavanones may mimic both simple-flavanones and simple-stilbenes depending upon the type and position of the substituent in their respective terminal aromatic rings.

Effects of hexagonal boron nitride nanoparticles on antimicrobial and antibiofilm activities, cell viability

The objective of this work was to investigate the antimicrobial and antibiofilm activities of hBN nanoparticles against Streptococcus mutans 3.3, Staphylococcus pasteuri M3, Candida sp. M25 and S. mutans ATTC 25175. Minimum Inhibitory Concentration (MIC) of hBN nanoparticles were determined against Streptococcus mutans 3.3, Staphylococcus pasteuri M3, Candida sp. M25 growth. In addition, we aimed to evaluate the cytotoxic effects of hBN nanoparticles on human normal skin fibroblast (CCD-1094Sk, ATCC® CRL 2120 ™) and Madin Darby Canine Kidney (MDCK) cells by using various toxicological endpoints. Cell viability was assessed by MTT, SRB and PicoGreen assays. After experimental analyses, it was revealed that hBN nanoparticles show better MIC results. The MIC values were higher for Streptococcus mutans ATTC 25175 and Staphylococcus pasteuri M3 and lower against Streptococcus mutans 3.3, Candida sp. M25. Surprisingly, hBN nanoparticles showed a high antibiofilm activity on preformed biofilm, which inhibited biofilm growth of S. mutans 3.3, S. mutans ATTC 25175 and Candida sp.M25. These results show that hBN nanoparticles may be an option to control oral biofilms. In cell viability tests, the cells were exposed to 0.025-0.4 mg/mL concentrations of hBN nano particle suspension. The exposure time to the hBN nanoparticle suspensions were 24 h and 48 h. The results indicate that there is no cytotoxic effect on CRL 2120 and MDCK cells at the concentration range of 0.025-0.1 mg/mL. However, on both first and second day, hBN caused mild cytotoxicity on CRL-2120 cells at high hBN concentration (0.2-0.4 mg/mL). Considering all the results of this study, in appropriate concentration (0.1 mg/mL) hBN nanoparticles can be considered a potential safe oral care product.