Antagonism between curcumin and the topoisomerase II inhibitor etoposide: a study of DNA damage, cell cycle regulation and death pathways

New Insights into Dose-Dependent Effects of Curcumin on ARPE-19 Cells

Opposing dose-dependent effects of curcumin (Cur) have been documented in Retinal Pigment Epithelium (RPE); therefore, to shed the light on the mechanisms of action is crucial for ophthalmic applications. On this basis we explored new insights about the dose-dependent mechanisms triggered by Cur in human retinal pigment epithelial cells (ARPE-19). Three concentrations (0.01 mM; 0.05 mM; 0.1 mM) of Cur were tested, followed by morphological, molecular, and functional analysis of the cells. Cur 0.01 mM promotes a significant increase in cell proliferation, not affecting cell cycle progression and apoptosis; by contrast, Cur 0.05 mM and 0.1 mM block cellular proliferation and trigger S-phase cell cycle arrest without inducing apoptosis. The observation of neuronal-like morphological changes in Cur 0.05 mM and 0.1 mM were not associated with neuronal differentiation, as observed by the quantification of Neurofilament-200 and by the analysis of voltage-dependent currents by patch clamp. Evaluation of autophagic markers LC3BII and p62 revealed significant modulations, suggesting an important activation of autophagy in ARPE-19 cells treated with Cur 0.05 mM and Cur 0.1 mM; conversely, Cur 0.01 mM did not affect autophagy. Altogether, our findings show new dose-dependent mechanisms of action of Cur that suggest a wide therapeutic application in ocular diseases with different pathogenesis (i.e., proliferative vitreoretinopathy or Age-Related Macular Degeneration).

Study on the multitarget mechanism of alliin activating autophagy based on network pharmacology and molecular docking

Due to the rapid development of bioinformatics, network pharmacology and molecular docking approaches have been successfully applied in the investigation of mechanisms of action. Here, we combined network pharmacology and molecular docking to predict the targets and reveal the molecular mechanism responsible for regulating autophagy by alliin. Based on the influence of alliin on autophagy, the targets of alliin were screened on the basis of different rules such as structural similarity by Pharmmapper, and genes associated with autophagy were collected from the GeneCards database. We focused on clarifying the biological processes and signalling pathways related to autophagy. Through the cytoHubba plug-in and a series of integrated bioinformatics analyses, the top nine hub nodes with higher degrees were obtained. And finally, through the LibDock included in Discovery Studio 2019, molecular docking method was adopted to declare the reliability of the interaction between alliin and hub targets. The results suggest that alliin-activated autophagy was possibly associated with pathways in cancer and the PI3K-AKT signalling pathway. Furthermore, the potential targets (AKT1, MAPK14, MAPK, HSPA8, EGFR, HSP90AA1, SRC HSPA1A and HSP90AB1) were swimmingly screened on the basis of this practical strategy. Molecular docking analysis indicates that alliin can bind with AKT1 and EGFR with good binding scores. This network pharmacology could be an invaluable strategy for the investigation of action mechanisms of alliin-activated autophagy. This study not only provides new and systematic insights into the underlying mechanism of alliin on autophagy, but also provides novel ideas for network approaches for autophagy-related research.

Silica nanoparticles cause spermatogenesis dysfunction in mice via inducing cell cycle arrest and apoptosis

The widespread use of silica nanoparticles (SiNPs) has increased the risk of human exposure, which raised concerns about their adverse effects on human health, especially the reproductive system. Previous studies have shown that SiNPs could cause damage to reproductive organs, but the specific mechanism is still unclear. In this study, to investigate the underlying mechanism of male reproductive toxicity induced by SiNPs, 40 male mice at the age of 8 weeks were divided into two groups and then intraperitoneally injected with vehicle control or 10 mg/kg SiNPs per day for one week. The results showed that SiNPs could damage testicular structure, perturb spermatogenesis and reduce serum testosterone levels, leading to a decrease in sperm quality and quantity. In addition, the ROS level in the testis of exposed mice was significantly increased, followed by imbalance of the oxidative redox status. Further study revealed that exposure to SiNPs led to cell cycle arrest and apoptosis, as shown by downregulation of the expression of positive cell cycle regulators and the activation of TNF-α/TNFR Ⅰ-mediated apoptotic pathway. The results demonstrated that SiNPs could cause testicles injure via inducing oxidative stress and DNA damage which led to cell cycle arrest and apoptosis, and thereby resulting in spermatogenic dysfunction.

Is Curcumin the Answer to Future Chemotherapy Cocktail?

The rise in cancer cases in recent years is an alarming situation worldwide. Despite the tremendous research and invention of new cancer therapies, the clinical outcomes are not always reassuring. Cancer cells could develop several evasive mechanisms for their survivability and render therapeutic failure. The continuous use of conventional cancer therapies leads to chemoresistance, and a higher dose of treatment results in even greater toxicities among cancer patients. Therefore, the search for an alternative treatment modality is crucial to break this viscous cycle. This paper explores the suitability of curcumin combination treatment with other cancer therapies to curb cancer growth. We provide a critical insight to the mechanisms of action of curcumin, its role in combination therapy in various cancers, along with the molecular targets involved. Curcumin combination treatments were found to enhance anticancer effects, mediated by the multitargeting of several signalling pathways by curcumin and the co-administered cancer therapies. The preclinical and clinical evidence in curcumin combination therapy is critically analysed, and the future research direction of curcumin combination therapy is discussed.

Natural Polyphenols as Modulators of Etoposide Anti-Cancer Activity

Polyphenols are naturally occurring compounds found in abundance in fruits and vegetables. Their health-promoting properties and their use in the prevention and treatment of many human diseases, including cancer, have been known for years. Many anti-cancer drugs are derived from these natural compounds. Etoposide, which is a semi-synthetic derivative of podophyllotoxin, a non-alkaloid lignan isolated from the dried roots and rhizomes of Podophyllum peltatum or Podophyllum emodi (Berberidaceae), is an example of such a compound. In this review, we present data on the effects of polyphenols on the anti-cancer activity of etoposide in in vitro and in vivo studies.

Curcumin sensitizes Epstein-Barr-immortalized lymphoblastoid cell lines to inorganic arsenic toxicity

Chronic exposure to inorganic arsenic (iAs) through contaminated drinking water is an important health problem in certain countries. The use of phytochemicals such as curcumin has recently emerged as an alternative strategy for preventing cellular damage caused by iAs. The Epstein-Barr virus (EBV) affects ~90% of the population and experimental evidence suggested that curcumin mediates cytotoxicity against EBV-infected cells. Due to the potential for an interaction of these factors, the aim of the present study was to evaluate the effect of this phytochemical on iAs-related toxicity in EBV-infected cells. Two independent EBV-immortalized human lymphoblastoid cell lines (LCLs) were used as the model. The cell lines were first incubated with increasing concentrations of curcumin or iAs for 24 and 15 h, respectively, to determine the individual effects of each exposure on cell death. In the next experiment, cell cultures were pre-incubated with 5 µM curcumin for 9 h prior to treatment with 10 µM iAs for 15 h, followed by evaluation of cell death and the cell cycle profile via flow cytometry. The results indicated that individual treatment with either curcumin or iAs induced cell death in a concentration-dependent manner. Furthermore, curcumin pre-treatment enhanced iAs-induced cell death and promoted cell cycle arrest in G1 phase. Taken together, these results suggested that curcumin sensitizes EBV-positive LCLs to the cytotoxic effects of iAs.

Discovery of novel class of histone deacetylase inhibitors as potential anticancer agents

Selective inhibition of histone deacetylases (HDACs) is an important strategy in the field of anticancer drug discovery. However, lack of inhibitors that possess high selectivity toward certain HDACs isozymes is associated with adverse side effects that limits their clinical applications. We have initiated a collaborative initiatives between multi-institutions aimed at the discovery of novel and selective HDACs inhibitors. To this end, a phenotypic screening of an in-house pilot library of about 70 small molecules against various HDAC isozymes led to the discovery of five compounds that displayed varying degrees of HDAC isozyme selectivity. The anticancer activities of these molecules were validated using various biological assays including transcriptomic studies. Compounds 15, 14, and 19 possessed selective inhibitory activity against HDAC5, while 28 displayed selective inhibition of HDAC1 and HDAC2. Compound 22 was found to be a selective inhibitor for HDAC3 and HDAC9. Importantly, we discovered a none-hydroxamate based HDAC inhibitor, compound 28, representing a distinct chemical probe of HDAC inhibitors. It contains a trifluoromethyloxadiazolyl moiety (TFMO) as a non-chelating metal-binding group. The new compounds showed potent anti-proliferative activity when tested against MCF7 breast cancer cell line, as well as increased acetylation of histones and induce cells apoptosis. The new compounds apoptotic effects were validated through the upregulation of proapoptotic proteins caspases3 and 7 and downregulation of the antiapoptotic biomarkers C-MYC, BCL2, BCL3 and NFĸB genes. Furthermore, the new compounds arrested cell cycle at different phases, which was confirmed through downregulation of the CDK1, 2, 4, 6, E2F1 and RB1 proteins. Taken together, our findings provide the foundation for the development of new chemical probes as potential lead drug candidates for the treatment of cancer.

Kaempferol and Its Glycoside Derivatives as Modulators of Etoposide Activity in HL-60 Cells

Kaempferol is a polyphenol found in a variety of plants. Kaempferol exerts antitumor properties by affecting proliferation and apoptosis of cancer cells. We investigated whether kaempferol and its glycoside derivatives-kaempferol 3-O-[(6-O-E-caffeoyl)-β-D-glucopyranosyl-(1→2)]-β-D-galactopyranoside-7-O-β-D-glucuropyranoside (P2), kaempferol 3-O-[(6-O-E-p-coumaroyl)-β-D-glucopyranosyl-(1→2)]-β-D-galactopyranoside-7-O-β-D-glucuropyranoside (P5) and kaempferol 3-O-[(6-O-E-feruloyl)-β-D-glucopyranosyl-(1→2)]-β-D-galactopyranoside-7-O-β-D-glucuropyranoside (P7), isolated from aerial parts of Lens culinaris Medik.-affect the antitumor activity of etoposide in human promyelocytic leukemia (HL-60) cells. We analyzed the effect of kaempferol and its derivatives on cytotoxicity, DNA damage, apoptosis, cell cycle progression and free radicals induced by etoposide. We demonstrated that kaempferol increases the sensitivity of HL-60 cells to etoposide but does not affect apoptosis induced by this drug. Kaempferol also reduces the level of free radicals generated by etoposide. Unlike kaempferol, some of its derivatives reduce the apoptosis of HL-60 cells (P2 and P7) and increase the level of free radicals (P2 and P5) induced by etoposide. Our results indicate that kaempferol and its glycoside derivatives can modulate the activity of etoposide in HL-60 cells and affect its antitumor efficacy in this way. Kaempferol derivatives may have the opposite effect on the action of etoposide in HL-60 cells compared to kaempferol.

Predicting and Quantifying Antagonistic Effects of Natural Compounds Given with Chemotherapeutic Agents: Applications for High-Throughput Screening

Natural products have been used for centuries to treat various human ailments. In recent decades, multi-drug combinations that utilize natural products to synergistically enhance the therapeutic effects of cancer drugs have been identified and have shown success in improving treatment outcomes. While drug synergy research is a burgeoning field, there are disagreements on the definitions and mathematical parameters that prevent the standardization and proper usage of the terms synergy, antagonism, and additivity. This contributes to the relatively small amount of data on the antagonistic effects of natural products on cancer drugs that can diminish their therapeutic efficacy and prevent cancer regression. The ability of natural products to potentially degrade or reverse the molecular activity of cancer therapeutics represents an important but highly under-emphasized area of research that is often overlooked in both pre-clinical and clinical studies. This review aims to evaluate the body of work surrounding the antagonistic interactions between natural products and cancer therapeutics and highlight applications for high-throughput screening (HTS) and deep learning techniques for the identification of natural products that antagonize cancer drug efficacy.

In Vitro Assessment of Homeopathic Potencies of Hydrastis canadensis on Hormone-Dependent and Independent Breast Cancer

BACKGROUND

Breast cancer is the second leading cause of cancer-related deaths in women. Conventional treatment such as chemotherapy, hormonal therapy and radiotherapy has decreased the mortality rate among cancer patients but has also revealed long-term side effects. Drug resistance and toxicity to normal cells compound the problems associated with the use of modern medicines. Hence, complementary or alternative treatment options are being explored. The current study, using different homeopathic potencies of Hydrastis canadensis, was conducted to distinguish between any effects they might have on hormone-dependent and independent breast cancer.

MATERIALS AND METHODS

The cytotoxic effect of homeopathic medicine Hydrastis on hormone-dependent (MCF 7) and hormone-independent (MDA-MB-468) breast cancer cells was assessed using viability and colony-forming assays after 48 or 72 hours of treatment. Flow cytometry-based Annexin V-PI (propidium iodide), caspase 3 and cell cycle analysis was performed following treatment of cells with mother tincture or various potencies of Hydrastis (1C, 2C, 30C, 200C).

RESULTS

Different potencies of Hydrastis displayed selective cytotoxic effects against MCF 7 cells, but only marginal effects against MDA-MB-468. The maximum cytotoxicity was established in the case of 1C following 72 hours of treatment. Treatment of breast cancer cells revealed an increase in the G0/G1 cell population, along with an increase in the caspase 3 levels and induction of apoptosis.

CONCLUSION

Hydrastis may have a selective cytotoxic effect against hormone-dependent breast cancer MCF 7 cells, leading to cell cycle arrest in the G0/G1 phase, which could be the plausible reason for the induction of apoptosis. The results need to be validated in vivo.

Safety and efficacy of turmeric extract, turmeric oil, turmeric oleoresin and turmeric tincture from Curcuma longa L. rhizome when used as sensory additives in feed for all animal species

Following a request from the European Commission, the EFSA Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of turmeric extract, turmeric oil, turmeric oleoresin and turmeric tincture from Curcuma longa L. rhizome when used as sensory additives in feed and in water for drinking for all animal species. The FEEDAP Panel concludes that the additives under consideration are safe at the maximum proposed use levels: (i) turmeric extract at 15 mg/kg complete feed (or in water for drinking at comparable exposure) for all animal species; (ii) turmeric essential oil at 80 mg/kg feed for veal calves (milk replacer) and 20 mg/kg complete feed (or 20 mg/L) for all other species; (iii) turmeric oleoresin at 30 mg/kg complete feed (or 30 mg/L) for chickens for fattening and laying hens and 5 mg/kg complete feed (or 5 mg/L) for pigs, veal calves, cattle for fattening and dairy cows, sheep, goats, horses, rabbits and fish; (iv) turmeric tincture at 0.8 mL/L water for drinking for poultry, 6 mL per head and day for horses and 0.05 mL tincture/kg complete feed for dogs. No concerns for consumers were identified following the use of the additives at the proposed use level in animal nutrition. Turmeric extract, turmeric oil, turmeric oleoresin and turmeric tincture should be considered as irritants to skin and eyes and the respiratory tract and as skin sensitisers. The use of the additives in feed is not expected to pose a risk for the environment. Since turmeric and its preparations are recognised to flavour food and their function in feed would be essentially the same as that in food, no further demonstration of efficacy is considered necessary.

Interplay between Epigenetics, Expression of Estrogen Receptor- α, HER2/ERBB2 and Sensitivity of Triple Negative Breast Cancer Cells to Hormonal Therapy

Triple negative breast cancer (TNBC) cells are resistant to hormonal/targeted therapies. This study aims to investigate epigenetic differences between TNBC and other types of breast cancer and the effect of epigenetic modulation on the response of TNBC cells to hormonal therapy. Thus, we investigated (i) the expression of different epigenetic markers, (ii) the effect of epigenetic modifying agents on the expression of ERα and HER2/ERBB2 and (iii) the effect on the response to tamoxifen in four breast cancer cell lines with different hormonal receptor status. Our results revealed a differential expression patterns of epigenetic markers in the four breast cancer cells. In TNBC cells, histone deacetylases (HDAC) 1 and 2 were less expressed, whereas HDACs 4 and 6 were overexpressed. Interestingly, treatment with epigenetic modifiers resulted in (i) a pronounced increase in the expression of ERα and HER2/ERBB2 along with (ii) an increase in the sensitivity of TNBC cells to tamoxifen. Collectively, this study indicates a different epigenetic background for TNBC cells, which represses the expression of ERα and HER2/ERBB2. Furthermore, we provide here the rationale for the use of epigenetic modifiers to enhance the response of TNBC to hormonal therapy through upregulation of ERα.

Safranal induces DNA double-strand breakage and ER-stress-mediated cell death in hepatocellular carcinoma cells

Poor prognoses remain the most challenging aspect of hepatocellular carcinoma (HCC) therapy. Consequently, alternative therapeutics are essential to control HCC. This study investigated the anticancer effects of safranal against HCC using in vitro, in silico, and network analyses. Cell cycle and immunoblot analyses of key regulators of cell cycle, DNA damage repair and apoptosis demonstrated unique safranal-mediated cell cycle arrest at G2/M phase at 6 and 12 h, and at S-phase at 24 h, and a pronounced effect on DNA damage machinery. Safranal also showed pro-apoptotic effect through activation of both intrinsic and extrinsic initiator caspases; indicating ER stress-mediated apoptosis. Gene set enrichment analysis provided consistent findings where UPR is among the top terms of up-regulated genes in response to safranal treatment. Thus, proteins involved in ER stress were regulated through safranal treatment to induce UPR in HepG2 cells.

Inhibition of SHP2 by new compounds induces differential effects on RAS/RAF/ERK and PI3K/AKT pathways in different cancer cell types

Kinases and phosphatases are important players in growth signaling and are involved in cancer development. For development of targeted cancer therapy, attention is given to kinases rather than phosphatases inhibitors. Src homology region 2 domain-containing protein tyrosine phosphatase2 (SHP2) is overexpressed in different types of cancers. We investigated the SHP2-inhibitory effects of two new 5-aminosalicylate-4-thiazolinones in human cervical (HeLa) and breast (MCF-7 & MDA-MB-231) cancer cells. In-silico molecular docking showed preferential affinity of the two compounds towards the catalytic over the allosteric site of SHP2. An enzymatic assay confirmed the docking results whereby 0.01 μM of both compounds reduced SHP2 activity to 50%. On cellular level, the two compounds significantly reduced the expression of SHP2, KRAS, p-ERK and p-STAT3 in HeLa but not in the other two cell lines. Phosphorylation of AKT and JNK was enhanced in HeLa and MCF7. Both compounds exhibited anti-proliferative/anti-migratory effects on HeLa and MCF7 but not in MDA-MB-231 cells. These results indicate that inhibition of SHP2 and its downstream pathways by the two compounds might be a promising strategy for cancer therapy in some but not all cancer types.

Molecular characterization of the grape seeds extract's effect against chemically induced liver cancer: In vivo and in vitro analyses

The purpose of this study was to investigate the anti-cancer property of grape seed extract (GSE) during early stages of developing liver cancer using a two-stage carcinogenic model combining diethylnitrosamine (DEN) and 2-Acetyl Aminofluorene (2-AAF). Administration of GSE at doses 25, 50 and 100 mg/kg per day started at the beginning of promotion periods and continued for 14 weeks. GSE dramatically inhibited pre-neoplastic foci formation as well as significantly decreased the number and the area of placental glutathione-S-transferase in livers of DEN-2AAF-treated rats by approximately 4 & 10 fold deductions, respectively. GSE's effects were associated with induced apoptosis, reduced cell proliferation, decreased oxidative stress and down regulation of histone deacetylase activity and inflammation makers, such as cyclooxygenase 2, inducible nitric oxide synthase, nuclear factor-kappa B-p65 and p- phosphorylated tumor necrosis factor receptor expressions in liver. GSE treatment also decreased the viability of HepG2 cells and induced early and late apoptosis through activating caspase-3 and Bax. Furthermore, GSE induced G2/M and G1/S cell cycle arrest. The present study provides evidence that the GSE's anticancer effect is mediated through the inhibition of cell proliferation, induction of apoptosis, modulating oxidative damage and suppressing inflammatory response.

Anticancer Effect of a Novel Octahydropyrazino[2,1-a:5,4-a']diisoquinoline Derivative and Its Synergistic Action with Nigella sativa in Human Gastric Cancer Cells

Many studies have shown that naturally occurring compounds may support prevention and treatment of various diseases, including cancer. Pharmacological investigations revealed a wide spectrum of Nigella sativa biological activities. Combining natural compounds together with synthetic drugs may increase the anticancer activity and limit severe side effects of such a treatment and may be an alternative to monotherapy. The aim of the study was to evaluate the cytotoxic and proapoptotic effects of a novel octahydropyrazino[2,1-a:5,4-a']diisoquinoline derivative and its effect in combination with Nigella sativa seed oil or extract in human gastric cancer cells (AGS). Etoposide was used as a reference. Our studies proved that combination strategy based on novel octahydropyrazino[2,1-a:5,4-a']diisoquinoline derivative (OM-90) with Nigella sativa seed oil or extract represents the strongest efficacy in AGS cancer cells as compared to monotherapy and combined treatment with Nigella sativa seed oil or extract together with etoposide. Such a combination also leads to the activation of mitochondrial pathway, which plays a significant role in molecular mechanism of induction of apoptosis by these compounds.

Complementary and alternative medicine use among cancer patients in Palestine with special reference to safety-related concerns

ETHNOPHARMACOLOGICAL RELEVANCE

The use of CAM including herbal medicine as the most preferred CAM modality, among cancer patients who are taking prescription medications has shown to be highly prevalent worldwide as well as in several Middle Eastern countries, with a high percentage of the patients do not disclose their CAM use to treating physician.

AIM OF THE STUDY

The current study aimed to evaluate the patterns of CAM use among two cohorts of cancer patients in Palestine over a three-year period, and to identify socio-demographic factors that are associated with CAM use.

MATERIALS AND METHODS

Across-sectional survey of patients attending outpatient cancer clinics. The method was based on a semi-structured questionnaire. In order to identify safety-related concerns associated with the products listed, a literature search was conducted using different databases (PubMed, Micromedex, AltMedDex, and the Natural Medicine Comprehensive Database).

RESULTS

In 472 cancer patients including 372 of the 2011 cohort; and 100 of the 2014 cohort, the overall prevalence of CAM use was 69.5%. CAM users were more likely to be ≤65 years old, village resident, being in the midst of chemotherapy, to have high interest spiritual quest, and to have no other chronic diseases. A significant number of CAM users reported using herbal preparations (98.3%, and 89.6% in the two study cohorts, respectively). In the current study, a total of 40 plant taxa belonging to 23 botanical families were reported by ≥3 cancer patients in the two cohort groups. The top most commonly used plant in the 2011 cohort group was Arum palaestinum (43.5%), while Ephedra foeminea emerged as the top most commonly utilized plant (from 0.0% in 2011 to 55.2% in the 2014 cohort), mainly due to a recent publicizing and portraying of the plant in the local media as an effective cancer herbal remedy. Safety-related concerns were associated with 33 (82.5%) herbs, including herb-drug interactions with altered pharmacokinetics (8, 20% herbs), direct toxic effects (16, 40% herbs), and increased in vitro response of cancer cells to chemotherapy (30, 75% herbs).

CONCLUSIONS

CAM use, especially herbal medicine in cancer is highly prevalent in Palestine. This study has demonstrated the role of the media on the emergence of new CAM herbal therapies among cancer patients in Palestine, and discussed its potential implications on patients and for oncologists who are treating them. Some of the most widely used herbal medicines by cancer patients in the present work are known to interact with conventional anticancer drugs. Hence, the disclosure of the use of herbal remedies by patients to health professionals with sufficient training in CAM use is important for the later in order to assess whether there are any possible herbal drug interactions and/or harmful drug reactions.

Epigenetics and miRNA as predictive markers and targets for lung cancer chemotherapy

Lung cancer cells show inherent and acquired resistance to chemotherapy. The lack of good predictive markers/novel targets and the incomplete understanding of the mechanisms of resistance limit the success of lung cancer response to chemotherapy. In the present study, we used an isogenic pair of lung adenocarcinoma cell lines; A549 (wild-type) and A549DOX11 (doxorubicin resistant) to study the role of epigenetics and miRNA in resistance/response of non-small cell lung cancer (NSCLC) cells to doxorubicin. Our results demonstrate differential expression of epigenetic markers whereby the level of HDACs 1, 2, 3 and4, DNA methyltransferase, acetylated H2B and acetylated H3 were lower in A549DOX11 compared to A549 cells. Fourteen miRNAs were dys-regulated in A549DOX11 cells compared to A549 cells, of these 14 miRNAs, 4 (has-mir-1973, 494, 4286 and 29b-3p) have shown 2.99 - 4.44 fold increase in their expression. This was associated with reduced apoptosis and higher resistance of A549DOX11cells to doxorubicin and etoposide. Sequential treatment with the epigenetic modifiers trichostatin A or 5-aza-2'-deoxycytidine followed by doxorubicin resulted in: (i) enhanced sensitivity of both cell lines to doxorubicin especially at low concentrations, (ii) enhanced doxorubicin-induced DNA damage in both cell lines, (iii) dysregulation of some miRNAs in A549 cells. In conclusion, A549DOX11 cells resistant to DNA damaging drugs have epigenetic profile and miRNA expression different from the sensitive cells. Moreover, epigenetic modifiers may reverse the resistance of certain NSCLC cells to DNA damaging agents by enhancing induction of DNA damage. This may open the door for using epigenetic profile/miRNA expression of some cancer cells as resistance markers/targets to improve response of resistant cells to doxorubicin and for the use of combination doxorubicin/epigenetic modifiers to reduce doxorubicin toxicity.

Protective effect of curcumin on chemotherapy-induced intestinal dysfunction

OBJECTIVE

Chemotherapy is one of most important treatments for human cancers. However, side effects such as intestine dysfunction significantly impaired its clinical efficacy. This study aimed to investigate the protective effect of Curcumin on chemotherapy-induced intestinal dysfunction in rats.

METHODS

Sixty healthy Wistar rats were randomly divided into control group (normal saline), 5-FU group and 5-FU+Curcumin group. The weight, serum level of endotoxin, DAO and D-lactate were determined. The pathological change of intestinal mucosa structure was studied under light microscopy and electron microscopy. The expression of Bax, Bcl-2 and Caspase-3 were assessed by immunohistochemical staining.

RESULTS

The Curcumin intragastrically administrated obviously reduced 5-FU-induced weight-loss. 5-FU induced dramatic increase of serum endotoxin, D-lactate and D-Amino-Acid Oxidase (DAO) that were significantly reversed by Curcumin treatment. Meanwhile, 5-FU-induced-damage to intestinal mucosa structure was markedly recovered by Curcumin. The expression of Bax and Caspase-3 were dramatically increased after 5-FU treatment (p<0.01) and Curcumin treatment significantly reduced Bax expression (p<0.05) but had only a moderate effect on reducing caspase-3 expression (p>0.05). Interestingly, Bcl-2 expression was low in control group but increased after 5-FU treatment (p>0.05) and Curcumin treatment further stimulated Bcl-2 expression (p<0.05).

CONCLUSIONS

Curcumin can significantly reverse chemotherapy-induced weight-loss, increase of serum endotoxin, D-lactate and DAO and damage to intestinal mucosa structure. Curcumin also reduced the expression of pro-apoptotic Bax but stimulated anti-apoptotic Bcl-2 to attenuate 5-FU-induced apoptosis of intestinal epithelial cells. The clinical administration of Curcumin may improve chemotherapy-induced intestinal dysfunction, thus increasing the clinical efficacy of chemotherapy.

Curcuma Contra Cancer? Curcumin and Hodgkin's Lymphoma

Curcumin, a phytochemical isolated from curcuma plants which are used as coloring ingredient for the preparation of curry powder, has several activities which suggest that it might be an interesting drug for the treatment or prevention of cancer. Curcumin targets different pathways which are involved in the malignant phenotype of tumor cells, including the nuclear factor kappa B (NFKB) pathway. This pathway is deregulated in multiple tumor entities, including Hodgkin’s lymphoma (HL). Indeed, curcumin can inhibit growth of HL cell lines and increases the sensitivity of these cells for cisplatin. In this review we summarize curcumin activities with special focus on possible activities against HL cells.