MicroRNA-Mediated Antiproliferative Effects of M1 Macrophage-Derived Extracellular Vesicles on Melanoma Cells.

INTRODUCTION: Research in tumor treatment has shown promising results using extracellular vesicles (EVs) derived from immune cells. EVs derived from M1 macrophages (proinflammatory), known as M1-EVs, have properties that suppress tumor growth, making them a promising treatment tool for immune susceptible tumors such as melanoma. Here, small unaltered M1-EVs (M1-sEVs) were employed in a 3D mouse melanoma model (melanospheres) to evaluate such activity. METHODS: Macrophages were polarized and EVs were isolated by ultracentrifugation. The EVs obtained were characterized based on size, with measurements performed by dynamic light scattering and electron microscopy, and the expression profiles of microRNAs were analyzed by microarray and PCR. Melanospheres were used to evaluate the cytotoxicity of M1-sEVs. Pondering a possible future transposition from the animal model to the human, human melanoma cells were transfected with a specific miRNA, and the impact on cell proliferation was evaluated. RESULTS: The isolated EVs showed a size distribution between 50-400 nm in diameter, but preeminently in a range of 70-90 nm. M1-sEVs demonstrated a remarkable ability to reduce cell proliferation and viability in the melanospheres, leading to a decrease in their volume. M1-sEVs contained unique miRNAs, including miR-29a-3p, which exhibited significant antitumor activities according to bioinformatics analysis. Validation of the antitumor effects of miR-29a-3p was obtained by a functional evaluation, i.e., by inducing miRNA overexpression in human melanoma cells (SK-MEL-28). CONCLUSION: Although further research would be advisable, the study provides evidence supporting the potential of M1-sEVs and their miRNA load as a possible targeted immune therapy for melanoma.

MicroRNAs as serum biomarker for Senecio brasiliensis poisoning in cattle.

Senecio spp. is one of the most frequent plant-related poisonings in cattle. Its ingestion generates the disease seneciosis, characterized by hepatic damages. Liver biopsies and serum markers dosage are tools used in diagnosis; however, many breeding cattle are undiagnosed. MicroRNAs are non-coding RNA, stable in biological fluids. Their difference in expression levels may indicate the presence of the poisoning. We analyzed the miRNA profiling to identify potential diagnostic biomarkers for Senecio brasiliensis poisoning. The expression of miR-21, miR-885, miR-122, miR-181b, miR-30a, miR-378, and let-7 f were evaluated in the serum of exposed cattle. At least one histological change was found in liver and lower quantity of albumin and high AST and ALP were also detected. MiRNAs miR-30a, miR-378, miR-21, miR-885, and miR-122 presented significantly higher expression in intoxicated animals than in healthy animals. Furthermore, miR-122, miR-885, and, especially, miR-21 signatures demonstrated high sensitivity and specificity, with potential application for detecting poisoning.

MicroRNAs: Potential biomarkers for reproduction, diagnosis, prognosis, and therapeutic in domestic animals.

MicroRNA (miRNAs) are small non-coding RNA molecules involved in a wide range of biological processes through the post-transcriptional regulation of gene expression. Most studies evaluated microRNA expression in human, and despite fewer studies in veterinary medicine, this topic is one of the most exciting areas of modern veterinary medicine. miRNAs showed to be part of the pathogenesis of diseases and reproduction physiology in animals, making them biomarkers candidates. This review provides an overview of the current knowledge regarding miRNAs' role in reproduction and animal diseases, diagnostic and therapy.

Bioactive compounds, antioxidant capacity and antitumoral activity of ethanolic extracts from fruits and seeds of Eugenia involucrata DC.

Eugenia involucrata DC. (Myrtaceae) is a native tree species from Brazil that has been scarcely studied. We investigated the phenolic composition, the antioxidant capacity and the antitumoral activity of ethanolic extracts from fruits (FE) and seeds (SE) of E. involucrata. Six anthocyanins were identified by UPLC-PDA/MS/MS in FE, being four derived from cyanidin, and the other ones derived from delphinidin and pelargonidin. Using HPLC-PDA, FE presented a larger number of phenolic compounds (epicatechin, catechin, rutin, ellagic acid, myricetin and quercetin) than SE, which did not show myricetin and quercetin. However, SE showed higher total phenolic content and generally stronger in vitro antioxidant capacity than FE, except that only FE exhibited superoxide radical scavenging activity, which may be attributed to the anthocyanins present in fruits. Additionally, only SE exhibited antitumoral activity in a pancreatic cancer cell line (PANC-1). The antitumoral mechanisms involved imbalance of antioxidant status, alteration of mitochondrial membrane potential, cytoskeleton disassembly and induction of cell death by apoptosis and necrosis. Compared to the standard antitumoral drug gemcitabine, SE exhibited higher antitumoral efficacy and selectivity index. The highest concentration of total phenolics and of specific phenolic compounds bearing antitumoral properties may be related to the antitumoral activity of SE. Our results corroborate previous data of E. involucrata as an important source of bioactive compounds and provide, for the first time, evidences of in vitro antitumoral potential of its seeds on pancreatic cancer cell line.

MicroRNA profiles in serum samples from Acute-On-Chronic Liver Failure patients and miR-25-3p as a potential biomarker for survival prediction.

Acute-on-chronic liver failure (ACLF) is a condition characterized by acute decompensation of cirrhosis, associated with organ failure(s), and high short-term mortality. The microRNAs or miRNAs are small non-coding RNA molecules, stable in circulating samples such as biological fluids, and the difference in expression levels may indicate the presence, absence and/or stage of the disease. We analyzed here the miRNA profiling to identify potential diagnostic or prognostic biomarkers for ACLF. The major miRNAs discovered were validated in a cohort of patients with acute decompensation of cirrhosis grouped in no ACLF or ACLF according to EASL-CLIF definition. Relationship between serum miRNAs and variables associated with liver-damage and survival outcomes were verified to identify possible prognostic markers. Our results showed twenty altered miRNAs between no ACLF and ACLF patients, and twenty-seven in patients who died in 30 days compared with who survived. In validation phase, miR-223-3p and miR-25-3p were significantly altered in ACLF patients and in those who died in 30 days. miR-223-3p and miR-25-3p expression were associated with the lowest survival in 30 days. The decrease in miR-223-3p and miR-25-3p expression was associated with the presence of ACLF and poor prognosis. Of these, miR-25-3p was independently related to ACLF and 30-day mortality.

Tacrine derivatives stimulate human glioma SF295 cell death and alter important proteins related to disease development: An old drug for new targets.

Glioblastoma is the most common and aggressive glioma, characterized by brain invasion capability. Being very resistant to the current therapies, since even under treatment, surgery, and chemotherapy with temozolomide (TMZ), patients achieve a median survival of one year. In the search for more effective therapies, new molecules have been designed. For nervous system cancers, molecules able to cross the blood-brain barrier are handled with priority. Accordingly, tacrine was chosen for this study and the inclusion of spiro-heterocyclic rings was done in its structure resulting in new compounds. Cytotoxic activity of tacrine derivatives was assayed using glioblastoma cell line (SF295) as well as analyzing cell death mechanism. Increased caspases activities were observed, confirming apoptosis as cell death type. Some derivatives also increased reactive oxygen species formation and decreased the mitochondrial membrane potential. Moreover, compounds acted on several glioblastoma-related proteins including p53, HLA-DR, beta-catenin, Iba-1, MAP2c, Olig-2, and IDH1. Therefore, tacrine derivatives presented promising results for the development of new glioblastoma therapy, particularly to treat those patients resistant to TMZ.

Solid lipid nanoparticles improve octyl gallate antimetastatic activity and ameliorate its renal and hepatic toxic effects.

Metastasis is the main cause of cancer-related death and requires the development of effective treatments with reduced toxicity and effective anticancer activity. Gallic acid derivatives have shown significant biological properties including antitumoral activity as shown in a previous study with octyl gallate (G8) in vitro. Thus, the aim of this work was to evaluate the antimetastatic effect of free and solid lipid nanoparticle-loaded G8 in mice in a lung metastasis model. Animals inoculated with melanoma cells presented metastasis in lungs, which was significantly inhibited by treatment with G8 and solid lipid nanoparticle-loaded G8, named G8-NVM. However, G8-treated mice showed an increase in several toxicological parameters, which were almost completely circumvented by G8-NVM treatment. This study supports the need for pharmacological studies on new potential medicinal plants to treat cancer and can provide new perspectives on using nanotechnology to improve biological activities while decreasing the chemotherapy toxicological effects of anticancer drugs.

Ficus umbellata Vahl. (Moraceae) Stem Bark Extracts Exert Antitumor Activities In Vitro and In Vivo.

A Ficus umbellata is used to treat cancer. The present work was therefore designed to assess antitumor potentials of F. umbellata extracts in nine different cell lines. Cell cycle, apoptosis, cell migration/invasion, levels of reactive oxygen species (ROS), mitochondrial membrane potential (MMP), caspases activities as well as Bcl-2 and Bcl-xL protein content were assessed in MDA-MB-231 cells. The 7,12-dimethylbenz(a)anthracene (DMBA)-induced carcinogenesis in rats were also used to investigate antitumor potential of F. umbellata extracts. The F. umbellata methanol extract exhibited a CC50 of 180 µg/mL in MDA-MB-231 cells after 24 h. It induced apoptosis in MCF-7 and MDA-MB-231 cells, while it did not alter their cell cycle phases. Further, it induced a decrease in MMP, an increase in ROS levels and caspases activities as well as a downregulation in Bcl-2 and Bcl-xL protein contents in MDA-MB-231 cells. In vivo, F. umbellata aqueous (200 mg/kg) and methanol (50 mg/kg) extracts significantly (p < 0.001) reduced ovarian tumor incidence (10%), total tumor burden (58% and 46%, respectively), average tumor weight (57.8% and 45.6%, respectively) as compared to DMBA control group. These results suggest antitumor potential of F. umbellata constituents possibly due to apoptosis induction mediated through ROS-dependent mitochondrial pathway.

Gallic Acid and Dodecyl Gallate Prevents Carbon Tetrachloride-Induced Acute and Chronic Hepatotoxicity by Enhancing Hepatic Antioxidant Status and Increasing p53 Expression.

Gallic acid (3,4,5-trihydroxybenzoic acid, GA), a natural phenolic acid has been reported as a strong antioxidant. Therefore the present study was designed to evaluate the effects of GA and dodecyl gallate (DGA) against acute and chronic carbon tetrachloride (CCl4)-induced hepatotoxicity. For acute model, rats were orally treated with GA and DGA for 7 d prior to CCl4 by intraperitoneally (i.p.) injection. For the chronic model, rats were orally treated with GA or DGA and CCl4 i.p. twice a week for four weeks. In both acute and chronic models, the CCl4-treated groups showed significantly increase in serum hepatic enzyme activities and histopathologic alterations, as well as a disruption in antioxidative status. In contrast, the treatment with GA and DGA restored serum hepatic enzymes activities, improved histopathologic alterations, increased glutathione (GSH) and decreased lipid peroxidation levels. The activities of liver antioxidant enzymes were increased by GA and DGA only in acute model. The expression of p53 gene increased about 3.5 times after GA and DGA treatments, which could result in cell death of damaged hepatocytes preventing of a lifelong liver failure. Thus, these results suggest that GA and DGA has the potential to prevent liver damages as the case of fibrosis condition.

Knockdown of antiapoptotic genes in breast cancer cells by siRNA loaded into hybrid nanoparticles.

Tumorigenesis is related to an imbalance in controlling mechanisms of apoptosis. Expression of the genes BCL-2 and BCL-xL results in the promotion of cell survival by inhibiting apoptosis. Thus, a novel approach to suppress antiapoptotic genes is the use of small interfering RNA (siRNA) in cancer cells. However, there are some limitations for the application of siRNA such as the need for vectors to pass the cell membrane and deliver the nucleic acid. In this study CaP-siRNA-PEG-polyanion hybrid nanoparticles were developed to promote siRNA delivery to cultured human breast cancer cells (MCF-7) in order to evaluate whether the silencing of antiapoptotic genes BCL-2 and BCL-xL by siRNA would increase cancer cell death. After 48 h of incubation the expression of BCL-2 and BCL-xL genes decreased to 49% and 23%, respectively. The siRNA sequence used induced cancer cell death at a concentration of 200 nM siRNA after 72 h of incubation. As the targeted proteins are related to the resistance to chemotherapeutic drugs, the nanocarriers systems were also tested in the presence of doxorubicin (DOX). The results showed a significant reduction in the CC50 of the DOX, after silencing the antiapoptotic genes. In addition, an increase in apoptotic cell counts for both incubations conditions was observed as well. In conclusion, silencing antiapoptotic genes such as BCL-2 and BCL-xL through the use of siRNA carried by hybrid nanoparticles showed to be effective in vitro, and presents a promising strategy for pre-clinical analysis, especially when combined with DOX against breast cancer.

Estrogenic and cytotoxic potentials of compounds isolated from Millettia macrophylla Benth (Fabaceae): towards a better understanding of its underlying mechanisms.

BACKGROUND: Millettia macrophylla was previously reported to have estrogenic effects and to prevent postmenopausal osteoporosis in Wistar rats. So, the study deals with the identification of its secondary metabolites and the evaluation of their estrogenicity and cytotoxicity toward tumoural cells. Thus, 13 known compounds were obtained from successive chromatographic columns and identified by NMR data compared to those previously reported. METHODS: In vitro estrogenicity of the isolates and the phenolic fraction (PF) of M. macrophylla were performed by E-screen and reporter gene assays, while their cytotoxicity was evaluated by Alamar Blue (resazurin) assay. A 3-days uterotrophic assay and the ability of PF to alleviate hot flushes in ovariectomized adult rats were tested in vivo. RESULTS: Seven of the 13 secondary metabolites turned to be estrogenic. Only two exhibited cytotoxic effects on MCF-7 and MDA-MB-231 with CC50 values of 110 µM and 160 µM, respectively. PF induced a significant (p < 0.01) MCF-7 cells proliferation and transactivated both ERα and ERß in the reported gene assay at 10-2 µg/mL. In vivo, PF acted more efficiently than the methanol crude extract, resulting to a significant (p < 0.01) increase in the uterine wet weight, uterine protein level, uterine and vaginal epithelial height at the dose of 10 mg/kg BW. In addition, PF reduced the average duration and frequency of hot flushes induced in rat. CONCLUSION: These aforementioned results indicate that PF is a good candidate for the preparation of an improved traditional medicine able to alleviate some menopausal complaints such as vaginal dryness and hot flushes. Estrogenic and cytotoxic potentials of compounds isolated from Millettia macrophylla Benth. (Fabaceae): towards a better understanding of its underlying mechanism.

N-phenylmaleimides affect adipogenesis and present antitumor activity through reduction of FASN expression.

In light of the evidence that in contrast to most healthy tissues, several neoplasms overexpress fatty acid synthase (FASN) upon their dependence on increased lipogenesis; targeting of this protein is being considered as a valuable strategy in anticancer drug development. This can be particularly relevant for aggressive tumors such as melanoma in which FASN overexpression has been associated with increased depth of invasion and worse prognosis. We have previously shown that a sub-class of cyclic imides, the N-phenylmaleimides, presented antitumor activity against L1210 leukemia and B16F10 melanoma with evidences of interference in the energetic metabolism. Here, we aimed to investigate if some selected N-phenylmaleimides (M1 and M5) interfere with fatty acids metabolism and its relation with cancer. For that, a model of pre-adipocytes differentiation (3T3-L1 cells) and also human melanoma cells (SK-Mel-147) were used. As results, when 3T3-L1 cells were exposed to non-cytotoxic concentrations of M1 and M5 in the presence of an adipogenic cocktail, intracellular lipid content decreased by 26-36%, marking the inhibition of adipocyte differentiation. High selectivity indexes were obtained for both compounds for tumoral cells. Cell cycle phases analysis revealed a remarkable proportion of cells with DNA fragmentation after their exposure to M1 and M5. This was correlated to both apoptosis and necrosis, showed by Annexin-V/PI assay. Furthermore, M1 and M5 reduced FASN expression by 19-39%, respectively. In conclusion, M1 and M5 presented antiadipogenic and antitumoral activities. The antitumoral activity that was associated to apoptosis and necrosis is a possible consequence of the FASN reduction, which in turn, might result in a fuel decrease to cell proliferation. As it happens with antiangiogenic activity, reduction of fatty acid synthesis might be a potential target for cancer treatment in a strategy of hunger-strike, which valorizes these N-phenylmaleimides as candidates for drug development.

New, highly potent and non-toxic, chromone inhibitors of the human breast cancer resistance protein ABCG2.

Breast cancer resistance protein (BCRP/ABCG2) is one of the major transporters involved in the efflux of anticancer compounds, contributing to multidrug resistance (MDR). Inhibition of ABCG2-mediated transport is then considered a promising strategy for overcoming MDR in tumors. We recently identified a chromone derivative, namely MBL-II-141 as a selective ABCG2 inhibitor, with relevant in vivo activity. Here, we report the pharmacomodulation of MBL-II-141, with the aim of identifying key pharmacophoric elements to design more potent selective and non-toxic inhibitors. Through rational structural modifications of MBL-II-141, using simple and affordable chemistry, we obtained highly active and easily-made inhibitors of ABCG2. Among the investigated compounds, derivative 4a, was found to be 3-fold more potent than MBL-II-141. It was similarly efficient as the reference inhibitor Ko143 but with the advantage of a lower intrinsic cytotoxicity, and therefore constitutes the best ABCG2 inhibitor ever reported displaying a very high therapeutic ratio.

Application of Response Surface Methodology for the Technological Improvement of Solid Lipid Nanoparticles.

Solid lipid nanoparticles (SLN) are colloidal particles consisting of a matrix composed of solid (at room and body temperatures) lipids dispersed in aqueous emulsifier solution. During manufacture, their physicochemical properties may be affected by several formulation parameters, such as type and concentration of lipid, proportion of emulsifiers and amount of solvent. Thus, the aim of this work was to study the influence of these variables on the preparation of SLN. A D-optimal Response Surface Methodology design was used to establish a mathematical model for the optimization of SLN. A total of 30 SLN formulations were prepared using the ultrasound method, and then characterized on the basis of their physicochemical properties, including particle size, polydispersity index (PI) and Zeta Potential (s). Particle sizes ranged between 107 and 240 nm. All SLN formulations showed negative sigma and PI values below 0.28. Prediction of the optimal conditions was performed using the desirability function targeting the reduction of all responses. The optimized SLN formulation showed similar theoretical and experimental values, confirming the sturdiness and predictive ability of the mathematical model for SLN optimization.

Development and Evaluation of Lipid Nanoparticles for Drug Delivery: Study of Toxicity In, Vitro and In Vivo.

Lipid nanoparticles have received considerable attention in the field of drug delivery, due their ability to incorporate lipophilic drugs and to allow controlled drug release. Solid lipid nanoparticles (SLN), nanostructured lipid carriers (NLC), and nanoemulsion (NE) are three different lipid nanostructured systems presenting intrinsically physical properties, which have been widely studied in recent years. Despite the extensive applicability of lipid nanoparticles, the toxicity of these systems has not been sufficiently investigated thus far. It is generally believed that lipids are biocompatible. However, it is known that materials structured in nanoscale might have their intrinsic physicochemical properties modified. Thus, the aim of this study was to evaluate the cytotoxicity of these three nanoparticle systems. To this end, in vitro and in vivo toxicity studies were carried out. Our results indicate that nanoparticles containing the solid lipid GMS (SLN and NLC) induced an important cytotoxicity in vitro, but showed minimal toxicity in vivo--evidenced by the body weight analysis. The NE did not induce in vitro toxicity and did not induce body weight alteration. On the contrary, the SLN and NLC possibly induce an inflammatory process in vivo. All nanoparticle systems induced lipid peroxidation in the animals' livers, but only SLN and NLC induced a decrease of antioxidant defences indicating that the main mechanism of toxicity is the induction of oxidative stress in liver. The higher toxicity induced by SLN and NLC indicates that the solid lipid GMS could be the responsible for this effect. Nevertheless, this study provides important insights for toxicological studies of different lipid nanoparticles systems.

Crateva adansonii DC, an African ethnomedicinal plant, exerts cytotoxicity in vitro and prevents experimental mammary tumorigenesis in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Crateva adansonii DC is a plant traditionally used in Cameroon to treat constipation, asthma, snakebites, postmenopausal complaints and cancers. AIM: The anticancer potential of the dichloromethane/methanol extract of C. adansonii stem barks was investigated using human breast cancer cell and 7,12 dimethylbenz(a)anththracene (DMBA)-induced mammary tumorigenesis model in rats. MATERIAL AND METHODS: The cytotoxicity of C. adansonii extract was assessed in vitro towards breast carcinoma (MCF-7 and MDA-MB-231) and non-tumoral cell lines (NIH/3T3 and HUVEC) by Alamar Blue assay. Furthermore, in vivo studies were performed on female Wistar rats treated either with C. adansonii extract at a dose of 75 or 300mg/kg body weight or with tamoxifen (3.3mg/kg body weight), starting 1 week prior DMBA treatment and lasted 12 weeks. The investigation focused on tumour burden, tumour DNA fingerprint, morphological, histological, hematological, and biochemical parameters. RESULTS: CC50 values for the in vitro assays were 289µg/mL against MCF-7 cells and >500µg/mL in others cells, leading to a selectivity index ≥1.73. C. adansonii extract significantly (p<0.001) revealed in vivo the reduction of the cumulative tumour yield (87.23%), total tumour burden (88.64%), average tumour weight (71.11%) and tumour volume (78.07%) at the dose of 75mg/kg as compared to DMBA control group. A weak effect was also observed at 300mg/kg. This extract showed a moderate hyperplasia at the dose of 75mg/kg while at 300mg/kg no significant change was noted as compared to DMBA group. It protected rats from the DNA alteration induced by DMBA and increased antioxydant enzymes activities in mammary gland tissue homogenates. In addition, Ultra-High Performance Liquid Chromatography/ESI-QTOF-Mass Spectrometry analysis of C. adansonii extract detected structure-related of many well-known anticancer agents such as flavane gallate, flavonol, phenylpropanoïds, sesquiterpene derivatives, gallotannins and lignans. The LD50 of C. adansonii was estimated to be greater than 5000mg/kg. CONCLUSIONS: These aforementioned results suggest that the C. adansonii extract may possess antitumor constituents, which could combat breast cancer and prevent chemically-induced breast cancer in rats.

Superparamagnetic iron-oxide nanoparticles mPEG350- and mPEG2000-coated: cell uptake and biocompatibility evaluation.

Superparamagnetic iron oxide nanoparticles (SPIONS) were synthesized by thermal decomposition of an organometallic precursor at high temperature and coated with a bi-layer composed of oleic acid and methoxy-polyethylene glycol-phospholipid. The formulations were named SPION-PEG350 and SPION-PEG2000. Transmission electron microscopy, X-ray diffraction and magnetic measurements show that the SPIONs are near-spherical, well-crystalline, and have high saturation magnetization and susceptibility. FTIR spectroscopy identifies the presence of oleic acid and of the conjugates mPEG for each sample. In vitro biocompatibility of SPIONS was investigated using three cell lines; up to 100µg/ml SPION-PEG350 showed non-toxicity, while SPION-PEG2000 showed no signal of toxicity even up to 200µg/ml. The uptake of SPIONS was detected using magnetization measurement, confocal and atomic force microscopy. SPION-PEG2000 presented the highest internalization capacity, which should be correlated with the mPEG chain size. The in vivo results suggested that SPION-PEG2000 administration in mice triggered liver and kidney injury. FROM THE CLINICAL EDITOR: The potential use of superparamagnetic iron oxide nanoparticles (SPIONS) in the clinical setting have been studied by many researchers. The authors synthesized two types of SPIONS here and investigated the physical properties and biological compatibility. The findings should provide more data on the design of SPIONS for clinical application in the future.

Estrogenic effects of Ficus umbellata Vahl. (Moraceae) extracts and their ability to alleviate some menopausal symptoms induced by ovariectomy in Wistar rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Ficus umbellata Vahl. (Moraceae) is a medicinal plant used in Cameroon to treat amenorrhea as well as other physiological disorders related to menopause. AIM OF STUDY: In order to justify scientifically its traditional use, the estrogen-like properties of the aqueous (AE) and methanol (MeOH) extracts of F. umbellata were investigated. MATERIAL AND METHODS: In vitro, the ability of different extracts of F. umbellata to activate estrogen receptors α (ERα) and ß (ERß) in cell-based reporter gene assays using human embryonic kidney (HEK293T) cells transfected with ERs was tested. In vivo, a 3-day uterotrophic assay and the capacity of the extracts to alleviate hot flushes in ovariectomized adult rats were tested. Using a bioassay-guided fractionation the major compound of F. umbellata was isolated and tested in vitro on HEK293T-ERα and ERß cells. RESULTS: AE and MeOH extracts significantly altered ERα as well as ERß activities. In vivo, both extracts significantly increase the uterine and vaginal epithelium thickness, and uterine total protein levels in a dose dependent manner. Interestingly, both extracts of F. umbellata at the dose of 100 mg/kg BW significantly decreased the total number, average duration as well as frequency of hot flushes in experimental rats compared to age-matched OVX controls. Finally, 7-methylumbelliferone, a coumarin was characterized as the major compound of F. umbellata; however this compound did not transactivate ERα as well ERß in vitro. CONCLUSION: These aforementioned results suggest that F. umbellata extracts as used by the traditional practitioner have estrogen-like effects and may alleviate some menopausal problems such as vaginal dryness and hot flushes.

Flavonoids, Breast Cancer Chemopreventive and/or Chemotherapeutic Agents.

Flavonoids are secondary metabolites abundantly present in commonly consumed fruits and vegetables. They possess diverse properties such as anti-inflammatory, anti-oxidant and anti-cancer. Epidemiologic studies suggest that an enrich flavonoids diet is linked to a decreased risk of breast cancer. These protective properties are due to the alteration of numerous signalling pathways involved in cancer-related phenomena such as inflammation and proliferation. Human clinical trials examining the effect of supplementation of some flavonoids on disease prevention have been conducted. There is no natural flavonoid that has been approved for the treatment of breast cancer. However, natural flavonoids served as lead compounds in the synthesis of cancer chemopreventive and/or therapeutic agents.

Phenolic indeno[1,2-b]indoles as ABCG2-selective potent and non-toxic inhibitors stimulating basal ATPase activity.

Ketonic indeno[1,2-b]indole-9,10-dione derivatives, initially designed as human casein kinase II (CK2) inhibitors, were recently shown to be converted into efficient inhibitors of drug efflux by the breast cancer resistance protein ABCG2 upon suited substitutions including a N (5)-phenethyl on C-ring and hydrophobic groups on D-ring. A series of ten phenolic and seven p-quinonic derivatives were synthesized and screened for inhibition of both CK2 and ABCG2 activities. The best phenolic inhibitors were about threefold more potent against ABCG2 than the corresponding ketonic derivatives, and showed low cytotoxicity. They were selective for ABCG2 over both P-glycoprotein and MRP1 (multidrug resistance protein 1), whereas the ketonic derivatives also interacted with MRP1, and they additionally displayed a lower interaction with CK2. Quite interestingly, they strongly stimulated ABCG2 ATPase activity, in contrast to ketonic derivatives, suggesting distinct binding sites. In contrast, the p-quinonic indenoindoles were cytotoxic and poor ABCG2 inhibitors, whereas a partial inhibition recovery could be reached upon hydrophobic substitutions on D-ring, similarly to the ketonic derivatives.