Search

The present study is designed to find out if sesquiterpenes, α-humulene (HUM), valencene (VAL), β-caryphyllene-oxide (CAO) and trans-nerolidol (NER), are able to improve the antiproliferative effect of classical cytostatic drugs, 5-fluorouracil (FU) and oxaliplatin (1,2-diaminocyclohexaneoxalato-platinum, OxPt), in colon cancer cell lines Caco-2 and SW-620. In addition, the possible mechanisms of sesquiterpene action are studied. The results show significant ability of HUM and especially of CAO to enhance the anti-proliferative effects of FU and OxPt in cancer cell lines Caco-2 and SW-620. On the other hand, VAL and NER are ineffective. The action of CAO could be partly based on its ability to disrupt the mitochondrial membrane potential and to activate initiator caspases, but other mechanisms are probably also involved. Based on these results, CAO seems to have the potential for combination therapy of colon cancers and deserves further study.

Graphene and its derivatives are popular nanomaterials used worldwide in many technical fields and biomedical applications. Due to such massive use, their anticipated accumulation in the environment is inevitable, with a largely unknown chronic influence on living organisms. Although repeatedly tested in chronic in vivo studies, long-term cell culture experiments that explain the biological response to these nanomaterials are still scarce. In this study, we sought to evaluate the biological responses of established model A549 tumor cells exposed to a non-toxic dose of pristine graphene for eight weeks. Our results demonstrate that the viability of the A549 cells exposed to the tested graphene did not change as well as the rate of their growth and proliferation despite nanoplatelet accumulation inside the cells. In addition, while the enzymatic activity of mitochondrial dehydrogenases moderately increased in exposed cells, their overall mitochondrial damage along with energy production changes was also not detected. Conversely, chronic accumulation of graphene nanoplates in exposed cells was detected, as evidenced by electron microscopy associated with impaired cellular motility.

Background: Given the increasing request for natural pharmacological molecules, this study assessed the antimicrobial capacity of Pistacia lentiscus L. essential oil (PLL-EO) obtained from the leaves of wild plants growing in North Sardinia (Italy) toward a wide range of periodontal bacteria and Candida, including laboratory and clinical isolates sp., together with its anti-inflammatory activity and safety., Methods: PLL-EO was screened by gas chromatography/mass spectrometry. The minimal inhibitory concentration (MIC) was determined. The anti-inflammatory activity was measured by cyclooxygenase (COX-1/2) and lipoxygenase (LOX) inhibition, while the antioxidant capacity was determined electro-chemically and by the MTT assay. The WST-1 assay was used to ascertain cytotoxicity toward four lines of oral cells., Results: According to the concentrations of terpens, PLL-EO is a pharmacologically-active phytocomplex. MICs against periodontal bacteria ranged between 3.13 and 12.5 µg/ml, while against Candida sp. they were between 6.25 and 12.5 µg/mL. Oxidation by COX-1/2 and LOX was inhibited by 80% and 20% µg/mL of the oil, respectively. Antioxidant activity seemed negligible, and no cytotoxicity arose., Conclusions: PLL-EO exhibits a broad-spectrum activity against periodontal bacteria and Candida , with an interesting dual inhibitory capacity toward COX-2 and LOX inflammatory enzymes, and without side effects against oral cells.

Flubendazole (FLU), an anthelmintic drug of benzimidazole type, is now considered a promising anti-cancer agent due to its tubulin binding ability and low system toxicity. The present study was aimed at determining more information about FLU reduction in human liver, because this information has been insufficient until now. Subcellular fractions from the liver of 12 human patients (6 male and 6 female patients) were used to study the stereospecificity, cellular localization, coenzyme preference, enzyme kinetics, and possible inter-individual or sex differences in FLU reduction. In addition, the risk of FLU interaction with other drugs was evaluated. Our study showed that FLU is predominantly reduced in cytosol, and the reduced nicotinamide adenine dinucleotide phosphate (NADPH) coenzyme is preferred. The strict stereospecificity of FLU carbonyl reduction was proven, and carbonyl reductase 1 was identified as the main enzyme of FLU reduction in the human liver. A higher reduction of FLU and a higher level of carbonyl reductase 1 protein were found in male patients than in female patients, but overall inter-individual variability was relatively low. Hepatic intrinsic clearance of FLU is very low, and FLU had no effect on doxorubicin carbonyl reduction in the liver and in cancer cells. All these results fill the gaps in the knowledge of FLU metabolism in human.

Inositol hexaphosphate (IP6), also known as phytic acid, has been shown to exhibit anticancer effects in a number of preclinical tumor models. IP6 decreases proliferation by arresting cells in the G0/G1 phase, inhibits iron-mediated oxidative reactions, enhances differentiation and stimulates apoptosis. The present study attempted to characterize the effect of IP6 on the migration and adhesion of colon cancer SW620 cells. IP6 was assessed at concentrations of 0.2 and 1 mM during 12, 24 and 48 h of exposure. Migration ability was measured with the real-time xCELLigence Real-Time Cell Analyzer Dual Purpose system. The expression of mRNA and proteins involved in migration and cancer progression [epithelial cell adhesion molecule, intercellular adhesion molecule-1, β-catenin, N-cadherin, E-cadherin, matrix metalloproteinase (MMP)-2 and MMP-9] was determined by reverse transcription-quantitative polymerase chain reaction and western blot analysis. The changes in the expression and subcellular localization of E-cadherin were determined by indirect immunofluorescence. IP6 induced a decrease in the migration ability of the tested SW620 cell line. IP6-treated cells also showed decreased expression of N-cadherin, increased levels of E-cadherin and decreased expression of MMP-2 and MMP-9. These results indicated that IP6 has potential to modulate the migration ability and expression of markers associated with invasion in SW620 cells; however, further analysis is necessary to obtain a detailed understanding of the mechanism of action.

Flubendazole (FLU), a benzimidazole anthelmintic drug widely used in veterinary medicine, has been approved for the treatment of gut-residing nematodes in humans. In addition, FLU is now considered a promising anti-cancer agent. Despite this, information about biotransformation of this compound in human is lacking. Moreover, there is no information regarding whether cancer cells are able to metabolize FLU in order to deactivate it. For these reasons, the present study was designed to identify all metabolites of Phase I and Phase II of FLU in human liver and in various cancer cells using ultra high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) analysis. Precision-cut human liver slices and 9 cell lines of different origin (breast, colon, oral cavity) were used as in vitro model systems. Our study showed that FLU with a reduced carbonyl group (FLUR) is the only FLU metabolite formed in the human liver. All human cancer cell lines were able to form FLUR. In addition, methylated FLUR was detected in breast cells MCF7 and intestinal SW480 cells. The accumulation of FLU and its reduction to FLUR markedly differed among cells. The extent of FLU reduction was in a good correlation with the detected expression level of carbonyl reductase 1. In most cases, FLU entered in a higher amount and was reduced to a lesser extent in proliferating (metastatic) cells than in differentiated (non-cancerous, non-metastatic) ones. These results support the promising potential of FLU in anti-cancer therapy., (Copyright © 2018 John Wiley & Sons, Ltd.)

Background: Colon cancer is the most common type of gastrointestinal cancer. Despite advances during the last two decades, the efficacy of colorectal cancer treatment is still insufficient and new anticancer agents are necessary., Methods: In our study, colon cancer cells derived from a primary tumor (SW480) and lymph node metastasis (SW620) from the same patient were used and compared. The effect of flubendazole (FLU) on cell adhesion and migration was monitored using the x-CELLigence Real-Time Cell Analysis system. Expressions of molecules involved in adhesion and migration were analyzed using RT-PCR and western blot. Furthermore, RNA silencing of nuclear factor-κB in SW620 cells was used to determine the involvement of the NF-κB p65 regulation pathway in FLU action., Results: FLU significantly suppressed the adhesion of SW480 cells and reduced the expression of adhesion markers (ICAM-1, αE-catenin; β-catenin; integrin α5 and β1). Moreover, a significant anti-migratory potential of FLU was manifested in the SW620 cells. In addition, FLU suppressed the phosphorylation of NF-κB p65 and potentiated the suppression of several metastatic markers (ICAM-1, EpCAM, integrin α5, β1, α-tubulin) caused by NF-κB p65 silencing., Conclusion: FLU has a significant anti-migratory effect in intestinal cancer cell SW480 and its lymph node metastatic cells SW620. FLU decreases the expression of some proteins involved in metastatic processes and inhibits activation of NF-κB p65., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: One approach to improve effect of chemotherapy is combination of classical cytostatic drugs with natural compounds, e. g. sesquiterpenes. In our previous study, sesquiterpenes β-caryophyllene oxide (CAO) and trans-nerolidol (NER) improved the anti-proliferative effect of doxorubicin (DOX) in intestinal cancer cell lines., Purpose: The present study was designed to evaluate the effect of CAO and NER on DOX efficacy, focusing on cell proliferation, migration, apoptosis and DOX accumulation in breast cancer cells MDA-MB-231 and MCF7 in vitro and in mice bearing solid Ehrlich tumors (EST) in vivo., Methods: The impact of cytotoxic effect was assessed by the neutral red uptake test. The ability to migrate was tested using real-time measurement in x-CELLigence system. Expressions of molecules were examined using western blot analysis. The accumulation of DOX inside the cells using time lapse microscopy was observed. The mice with inoculated EST cells were treated repeatedly with DOX and DOX+CAO or DOX+NER and the growth of tumors were monitored. DOX concentrations in plasma and tumor were assayed using HPLC., Results: In MDA-MB-231, combination of DOX with CAO enhanced anti-proliferative effect and acted strongly synergistic. NER increased accumulation of DOX inside the cells; moreover combination DOX with NER suppressed migration ability in vitro. In vivo, apoptosis was activated especially in group treated with DOX and CAO. However, none of tested sesquiterpenes was able to improve DOX accumulation in tumors and DOX-mediated inhibition of tumor growth., Conclusion: In conclusion, sesquiterpenes CAO and NER increased the efficacy of DOX in breast cancer cells in vitro, but did not improve its effect in vivo, in Ehrlich solid tumor bearing mice., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Objectives: Flubendazole (FLU), a member of benzimidazole family of anthelmintic drugs, is able to inhibit proliferation of various cancer cells. The aim of present study was to elucidate the mechanisms of antiproliferative effect of FLU on colorectal cancer cells in vitro., Methods: The effect of FLU on proliferation, microtubular network, DNA content, caspase activation and senescence induction was studied in SW480 and SW620 cell lines., Key Findings: Flubendazole significantly affected cell proliferation in a pattern typical for mitotic inhibitor. This was accompanied by decrease in cyclin D1 levels, increase in cyclin B1 levels, activation of caspase 2 and caspase 3/7 and PARP cleavage. Morphological observations revealed disruption of microtubular network, irregular mitotic spindles, formation of giant multinucleated cells and increase in nuclear area and DNA content. In SW620 cell line, 37.5% giant multinucleated cells induced by FLU treatment showed positivity for SA-β-galactosidase staining. Cell lines were able to recover from the treatment and this process was faster in SW480 cells., Conclusion: Flubendazole in low concentration temporarily inhibits cell proliferation and induces mitotic catastrophe and premature senescence in human colon cancer cells in vitro., (© 2015 Royal Pharmaceutical Society.)

Essential oil from the leaves of Myrica rubra, a subtropical Asian fruit tree traditionally used in folk medicines, has a significant antiproliferative effect in several intestinal cancer cell lines. Doxorubicin belongs to the most important cytostatics used in cancer therapy. The present study was designed to evaluate the effects of defined essential oil from M. rubra leaves on efficacy, prooxidative effect, and accumulation of doxorubicin in cancer cell lines and in non-cancerous cells. For this purpose, intestinal adenocarcinoma CaCo2 cells were used. Human fibroblasts (periodontal ligament) and a primary culture of rat hepatocytes served as models of non-cancerous cells. The results showed that the sole essential oil from M. rubra has a strong prooxidative effect in cancer cells while it acts as a mild antioxidant in hepatocytes. Combined with doxorubicin, the essential oil enhanced the antiproliferative and prooxidative effects of doxorubicin in cancer cells. At higher concentrations, synergism of doxorubicin and essential oil from M. rubra was proved. In non-cancerous cells, the essential oil did not affect the toxicity of doxorubicin and the doxorubicin-mediated reactive oxygen species formation. The essential oil increased the intracellular concentration of doxorubicin and enhanced selectively the doxorubicin accumulation in nuclei of cancer cells. Taken together, essential oil from M. rubra leaves could be able to improve the doxorubicin efficacy in cancer cells due to an increased reactive oxygen species production, and the doxorubicin accumulation in nuclei of cancer cells., (Georg Thieme Verlag KG Stuttgart · New York.)

The sesquiterpenes β-caryophyllene, β-caryophyllene oxide (CAO), α-humulene (HUM), trans-nerolidol (NER), and valencene (VAL) are substantial components of the essential oil from Myrica rubra leaves which has exhibited significant antiproliferative effects in several intestinal cancer cell lines, with CaCo-2 cells being the most sensitive. The present study was designed to evaluate the effects of these sesquiterpenes on the efficacy and toxicity of the anticancer drug doxorubicin (DOX) in CaCo-2 cancer cells and in primary culture of rat hepatocytes. Our results showed that HUM, NER, VAL and CAO inhibited proliferation of CaCo-2 cancer cells but they did not affect the viability of hepatocytes. CAO, NER and VAL synergistically potentiated the efficacy of DOX in cancer cells killing. All sesquiterpenes exhibited the ability to selectively increase DOX accumulation in cancer cells and did not affect DOX concentration in hepatocytes. Additionally, CAO and VAL were able to increase the pro-oxidative effect of DOX in CaCo-2 cells. Moreover, CAO mildly ameliorated DOX toxicity in hepatocytes. Based on all results, CAO seems to be the most promising compound for further testing.

This study aimed to test the antiproliferative effect of three benzimidazole anthelmintics in intestinal cancer cells and to investigate whether these drugs, which inhibit tubulin polymerization, can potentiate the efficacy of the microtubule-stabilizing drug paclitaxel (PTX). Four intestinal cancer cell lines, SW480, SW620, HCT8, and Caco2, with different origins and growth characteristics were used. The antiproliferative effect of albendazole (ABZ), ricobendazole (RBZ), flubendazole (FLU), and their combinations with PTX was tested using three different end-point viability assays, cell cycle distribution analysis, and the x-CELLigence System for real-time cell analysis. ABZ and FLU inhibited cell proliferation significantly in a concentration-dependent and time-dependent manner through cell arrest in the G2/M phase. RBZ was not effective at any concentration tested. The cell lines differed in sensitivity to FLU and ABZ, with HCT8 being the most sensitive, showing IC₅₀ values for ABZ and FLU that reached 0.3 and 0.9 μmol/l, respectively. Combinations of PTX+ABZ and PTX+FLU decreased cell viability more effectively when compared with treatment with individual drugs alone. The anthelmintic benzimidazole drugs ABZ and FLU show a significant cytostatic effect and potentiate the efficacy of PTX in intestinal cancer cells.

Sodium selenite (Se) is known to induce diverse stress responses in malignant cells which may lead to various types of cell death including apoptosis and/or autophagy. In colon cancer cells, Se activates several signaling pathways whose interactions and ultimate endpoints may vary in individual study models. In our previous work we showed differences in Se-dependent growth inhibition, cell cycle alterations and apoptosis in colon cancer cells with functional (HCT-116) and deleted (HCT-116-p53KO) p53. Moreover, detailed morphological and biochemical analyses revealed the presence of autophagy in Se-treated cells. Thus the aim of this study was to investigate in detail mechanisms, relationship and crosstalk between apoptosis and autophagy in Se-treated HCT-116 cancer cells differing in p53 status since p53 has been shown to play a well-known role in apoptosis but dichotomous role in autophagy. We report that the absence of p53 in malignant colonocytes changes patterns of response to Se-induced stress which include differential activation of MAP kinases (p38 - HCT-116 and JNK - HCT-116 p53KO) including their respective roles in the process of apoptosis and autophagy as well as the involvement of mTOR or PI3K signaling. Our results seem to suggest that deletion of p53 inevitably leads to a higher level of instability and delays in an individual cell decision in the face of stress whether to activate apoptosis or autophagy which may consequently occur simultaneously with mutual dichotomous relationship., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Sodium selenite has been reported to interfere with cell growth and proliferation and to induce cell death. Despite of our current knowledge, details about its effects on growth and behavior of colonocytes with differing p53 status remain unknown. In our study, we evaluated the antiproliferative, cell cycle specific and proapoptotic potential of sodium selenite in HCT-116 colorectal cells with wild type p53 and its isogenic control HCT-116-p53KO cell line. Cell proliferation in selenite-treated cells was followed by computer-enhanced time-lapse videomicroscopy, by measuring protein content (Coomassie Brilliant Blue assay), metabolic activity (WST-1) and DNA synthesis (BrdU). Changes in cell cycle were determined by flow cytometry and Western blotting. Cell death was measured with the nuclear fragmentation assay and caspase-3 immunostaining. We show that sodium selenite inhibits the growth and proliferation of colon cancer cells in a time- and dose-dependent manner, with HCT-116 cells being more sensitive than HCT-116-p53KO cells. Moreover, upon sodium selenite treatment, there was a tendency for cells to accumulate at G2 phase which was accompanied by the increasing expression of cyclin B1, Cdc2 p34, p21 and the sub G1 fraction of the cell cycle. In addition, PARP and nuclear fragmentation and activation of caspase-3 were more profound in HCT-116 cells versus HCT-116-p53KO cells, thus indicating important role of p53 and dependent signaling in selenite-induced toxicity.

A number of cytotoxicity assays are currently available, each of them using specific approach to detect different aspects of cell viability, such as cell integrity, proliferation and metabolic functions. In this study we compared the potential of five commonly employed cytotoxicity assays (WST-1, XTT, MTT, Brilliant blue and Neutral red assay) to detect antiproliferative effects of three selenium compounds, sodium selenite, seleno-L-methionine (SeMet) and Se-(Methyl)selenocysteine (SeMCys) on three colorectal cancer cell lines in vitro. Cells were exposed to the selected selenium compounds in the concentration range of 0-256 microM during 48 h. WST-1 and XTT failed to detect cytotoxic effect, with the exception of the highest concentration of selenium compounds tested. Conversely, the metabolic activity of selenium treated cells measured by WST-1 and XTT significantly increased in comparison to untreated controls. MTT, Neutral red and Brilliant blue assays were more sensitive and yielded mutually comparable results, with significant decrease of measured parameters in a concentration-dependent manner. To a smaller extent, the results were affected by the different chemical nature of the selenium compounds tested as well as by the biological properties of individual cell lines.

Colorectal cancer is among the most common cancers worldwide, in terms of overall mortality. Environmental factors have been identified to play the most important roles in the development of this disease, in particular diet and its specific components. Selenium is an important micronutrient engaged in the protection of colonic cells against a wide range of external and internal stressors. In addition, selenium has been reported to actively inhibit growth of malignant colonic cells as well as to induce their demise. Furthermore, besides its promising chemopreventive role in the various stages of colorectal cancer development, selected chemical forms of selenium have shown interesting interaction patterns with some cytostatic chemicals or inducers of apoptosis. The advantages of selected selenium preparations thus might reach beyond chemoprevention since they may be used in conjunction with established antioneoplastic drugs, thereby establishing new treatment modality for colorectal cancer. In addition to summarizing our current knowledge about the mechanisms whereby selenium imparts its chemopreventive potential in colon carcinogenesis, the possibilities of a combined use of selenium with other cytostatics and chemicals are discussed.

The experimental results obtained from a fruit garden at Krajné pointed out a different content of macrobiogenic elements in the leaves of plum trees infected with plum pox virus (PPV) as compared to healthy ones. Mineral nutrition of diseased trees was characteristic by lower relational values of topical levels of macrobiogenic elements especially those of N/P, N/K, (Ca + Mg)/K, and (N/P)/(N/K).

Cytotolerance of several implantative materials has been tested on the in vitro cells. The majority of mentioned materials showed inertion without influencing cells contacting them. They were saphir, "CH" ceramic and bioactive glass-ceramic "BAS". In contrast, the sample 5 of bioglass and partly "M" ceramic sample displayed interaction with cells. On macrocontact observation of cytotolerance, the area has been stated to create around samples in which strongly degenerated and dead were rarely scattered. These substances showed interactions with cells what is confirmed by clinical observation as well.