Antioxidative and antiproliferative evaluation of 2-(phenylselenomethyl)tetrahydrofuran and 2-(phenylselenomethyl)tetrahydropyran.

PURPOSE: To determine the antioxidant and antiproliferative influence of 2-(phenylselenomethyl)tetrahydrofuran (1a) and 2-(phenylselenomethyl)tetrahydropyran (2a) on colon cancer cell line HCT-116 and breast cancer cell line MDA-MB-231. METHODS: Cell viability was monitored in a dose-dependent manner using MTT assay. The concentration of superoxide anion radical (O2 •(-)) was determined spectrophotometrically. Spectrophotometric determination of nitrites (NO2 -) was performed by using the Griess method. Determination of total glutathione (GSH) was also performed spectrophotometrically. RESULTS: HCT-116 cell line was more sensitive to the effects of the investigated substances than MDA-MB-231 cell line. Also, it was noticed that 1a produced greater effect compared to 2a. Moreover, both investigated compounds decreased to a certain degree the oxidative stress by decreasing the O2•(-) and thus the peroxynitrite concentration. At the same time, 1a and 2a acted more efficiently in promoting the endogenous antioxidative capacities (increased GSH concentration) providing better self-defence capabilities for cells. CONCLUSION: Our findings showed that the investigated selenium compounds play an important role in reducing the levels of reactive oxygen species (ROS); therefore, we believe that, as antioxidants, they could prevent the processes arising as a consequence of oxidative stress, including cancer.

Potential of Orlistat to induce apoptotic and antiangiogenic effects as well as inhibition of fatty acid synthesis in breast cancer cells.

Breast cancer as most often women's cancer is the second cause of mortality worldwide. Research interest increased in testing non-standard drugs to suppress breast cancer progression and become significant supplements in anticancer therapy. The anti-obesity drug Orlistat showed significant ability for modulation of cancer cell metabolism via antiproliferative, proapoptotic, antiangiogenic, antimetastatic, and hypolipidemic effects. The anticancer potential of Orlistat was evaluated by cytotoxicity (MTT assay), type of cell death (AO/EB double staining), determination of redox status parameters (superoxide, hydrogen peroxide, lipid peroxidation, reduced glutathione), and total lipid levels with colorimetric methods, as well on angiogenesis-related (VEGF, MMP-9, CXCR4/CXCL12) and fatty acid synthesis-related (ACLY, ACC, FASN) parameters on gene and protein levels (immunocytochemistry and qPCR). Based on obtained results Orlistat induces significant cytotoxic, proapoptotic, and anti-angiogenic effects in MDA-MB-231, MDA-MB-468 and MCF-7 breast cancer cells, without significant cytotoxic effects on normal MRC-5 cells. It decreased total lipid levels and changed redox status parameters and cancer cell metabolism via suppression of genes and proteins involved and fatty acid synthesis. Based on showed, Orlistat may be an important supplement in antiangiogenic therapy against breast cancer with no side effects on normal cells, making it a good candidate for future clinical trials.

Antiproliferative and proapoptotic activities of methanolic extracts from Ligustrum vulgare L. as an individual treatment and in combination with palladium complex.

The aim of this study is to examine the growth inhibitory effects of methanolic leaf and fruit extracts of L. vulgare on HCT-116 cells over different time periods and their synergistic effect with a Pd(apox) complex. The antiproliferative activity of plant extracts alone or in combination with the Pd(apox) complex was determined using MTT cell viability assay, where the IC(50) value was used as a parameter of cytotoxicity. Results show that antiproliferative effects of L. vulgare extracts increase with extension of exposure time, with decreasing IC(50) values, except for 72 h where the IC(50) values for methanolic leaf extract were lower than for the fruit extract. The Pd(apox) complex alone had a weak antiproliferative effect, but combination with L. vulgare extracts caused stronger effects with lower IC(50) values than with L. vulgare extracts alone. The type of cell death was explored by fluorescence microscopy using the acridin orange/ethidium bromide method. Treatments with plant extracts caused typical apoptotic morphological changes in HCT-116 cells and co-treatments with Pd(apox) complex caused higher levels of apoptotic cells than treatment with plant extracts alone. The results indicate that L. vulgare is a considerable source of natural bioactive substances with antiproliferative activity on HCT-116 cells and which have a substantial synergistic effect with the Pd(apox) complex.

L-amino acid oxidase from snake venom: Biotransformation and induction of apoptosis in human colon cancer cells.

This study evaluated the potential of antitumor activity of snake venom from Vipera ammodytes and L-amino acid oxidase from Crotalus adamanteus on different colorectal cancer cell lines through determination of cytotoxic activity by MTT assay, pro-apoptotic activity by acridine orange/ethidium bromide staining, and concentrations of redox status parameters (superoxide, reduced glutathione, lipid peroxidation) by colorimetric methods. The expression of genes involved in the biotransformation process and metabolite efflux was determined by qPCR method, while protein expression of glutathione synthetase and P-glycoprotein were analysed by immunocytochemistry. The analysis of cell death shows that snake venom dominantly leads cells to necrosis. Induction of apoptosis by L-amino acid oxidase was in correlation with oxidative disbalance in cancer cells. Gene expression profile of membrane transporters and CYP genes were different in each cell line and in correlation with their sensitivity of treatment. Our results show that L-amino acid oxidase from snake venom is a potent cytotoxic substance with pronounced pro-apoptotic activity. The inhibition of P-glycoprotein suggests that L-amino acid oxidase is a good substance for furter research of antitumor effect, with unexpressed potential for occurrence of drug resistance in vitro.

Potential of Teucrium chamaedrys L. to modulate apoptosis and biotransformation in colorectal carcinoma cells.

ETHNOPHARMACOLOGICAL RELEVANCE: Teucrum chamaedrys L. is one of the known medicinal plants, useful for treatment of various health problems, especially digestive. In this study, we investigated methanol, ethyl-acetate and acetone extracts of T. chamaedrys in respect to their anticancer properties in SW480 colorectal cancer cells. MATERIALS AND METHODS: Cytotoxicity and proapoptotic potential were assessed by MTT cell viability assay and AO/EB double staining. Molecular mechanisms of induced apoptosis were determined by monitoring Fas receptor protein expression through immunofluorescence, Caspase 8 and 9 activity, as well as concentrations of O2.- spectrophotometrically. Additionally, mRNA expression of biotransformation enzymes (CYP1A1, CYP1B1, GSTP1) and membrane transporters (MRP1 and MRP2) involved in drug resistance were investigated by qPCR method. Qualitative analysis of individual phenolic compounds was performed by reversed phase HPLC-MS analysis. RESULTS: Methanol extract shows the best cytotoxicity and selectivity compared to ethyl-acetate and acetone extracts, mainly causing apoptosis of SW480 cells, without affecting normal HaCaT keratinocytes. The increased expression of Fas receptor protein and caspase 8 activity indicate that the death receptor-mediated pathway plays a crucial role in the observed apoptosis. The increased caspase 9 activity and O2.- concentration suggest that mitochondria are also involved in the apoptosis. T. chamaedrys methanol extract inhibits mRNA expression of CYP1A1, CYP1B1, GSTP1, MRP1 and MRP2 in SW480 cells. CONCLUSIONS: Induction of apoptosis and inhibition of CYP1A1, CYP1B1, GSTP1, MRP1 and MRP2 mRNA expression implies that T. chamaedrys can serve as a valuable source of bioactive compounds as dietary supplements or selective anticancer agents, with the ability to induce apoptosis and modulate drug resistance in colorectal cancer cells.

Real-time monitoring of cytotoxic effects of electroporation on breast and colon cancer cell lines.

PURPOSE: To study the effects of electroporation on different cell lines. MATERIAL: The effects of electroporation on human breast cancer (MDA-MB-231), human colon cancer (SW-480 and HCT-116), human fibroblast cell line (MRC-5), primary human aortic smooth muscle cells (hAoSMC) and human umbilical vein endothelial cells (HUVEC) were studied. Real-time technology was used for cell viability monitoring. Acridine orange/ethidium bromide assay was applied for cell death type determination. A numerical model of electroporation has been proposed. RESULTS: Electroporation induced inhibition of cell viability on dose (voltage) dependent way. The electroporation treatment 375-437.5Vcm-1 caused irreversible electroporation of cancer cells and reversible electroporation of healthy cells. The application of lower voltage rating (250Vcm-1) led to apoptosis as the predominant type of cell death, whereas the use of higher voltage (500Vcm-1) mainly caused necrosis. CONCLUSION: Electroporation represents a promising method in cancer treatment. Different cancer cell lines had different response to the identical electroporation treatment. Electroporation 375-437.5Vcm-1 selectively caused permanent damage of cancer cells (SW-480), while healthy cells (MRC-5, hAoSM and HUVEC) recovered after 72h. The type of cell death is dependent of electroporation conditions. The proposed numerical model is useful for the analysis of phenomena related to electroporation treatment.

Effects of acute in vivo cisplatin and selenium treatment on hematological and oxidative stress parameters in red blood cells of rats.

Although cisplatin (cisPt) is one of the most often used cytotoxic drugs in the treatment of cancer, its clinical application is associated with nephrotoxicity and a cumulative anemia. In this study, we evaluated posible protective effects of selenium (Se) on hematological and oxidative stress parameters in rats, acutely treated with cisPt. Four groups of Wistar albino rats included control rats, cisPt-treated (7.5 mg/kg of body weight of cisPt, i.p.), Se-treated (6 mg/kg of body weight of Na(2)SeO(4), i.p.), and Se and cisPt co-treated rats. The rats were killed 72 h after treatment; hematological and oxidative stress parameters were followed in red blood cells. The results showed depletion in platelet number induced by high acute doses of cisPt and strong utilization of reduced glutathione, resulting in elevation of GSSG/2 GSH ratio. Se treatment was followed by stimulated erythropoiesis, increased lipid peroxidation, and GSH depletion. Se and cisPt co-treatment were followed by stimulated erythropoiesis and significant recovery of reduced glutathione status when compared with cisPt-treated rats. In conclusion, acute doses of Se and cisPt primarily act as pro-oxidants. CisPt influenced antioxidative properties of exogenous Se and their synergistic effects may partially participate in protection against cisPt-induced toxicity.