Bisphenol A effects on gene expression in adipocytes from children: association with metabolic disorders.

Bisphenol A (BPA) is a xenobiotic endocrine-disrupting chemical. In vitro and in vivo studies have indicated that BPA alters endocrine-metabolic pathways in adipose tissue, which increases the risk of metabolic disorders and obesity. BPA can affect adipose tissue and increase fat cell numbers or sizes by regulating the expression of the genes that are directly involved in metabolic homeostasis and obesity. Several studies performed in animal models have accounted for an obesogen role of BPA, but its effects on human adipocytes - especially in children - have been poorly investigated. The aim of this study is to understand the molecular mechanisms by which environmentally relevant doses of BPA can interfere with the canonical endocrine function that regulates metabolism in mature human adipocytes from prepubertal, non-obese children. BPA can act as an estrogen agonist or antagonist depending on the physiological context. To identify the molecular signatures associated with metabolism, transcriptional modifications of mature adipocytes from prepubertal children exposed to estrogen were evaluated by means of microarray analysis. The analysis of deregulated genes associated with metabolic disorders allowed us to identify a small group of genes that are expressed in an opposite manner from that of adipocytes treated with BPA. In particular, we found that BPA increases the expression of pro-inflammatory cytokines and the expression of FABP4 and CD36, two genes involved in lipid metabolism. In addition, BPA decreases the expression of PCSK1, a gene involved in insulin production. These results indicate that exposure to BPA may be an important risk factor for developing metabolic disorders that are involved in childhood metabolism dysregulation.

Curcumin loaded PLGA-poloxamer blend nanoparticles induce cell cycle arrest in mesothelioma cells.

The pharmacological potential of curcumin (CURC) is severely restricted because of its low water solubility/absorption, short half-life and poor bioavailability. To overcome these issues, CURC-loaded nanoparticles (NPs) were produced by a double emulsion technique. In particular, NPs were made up of an amphiphilic blend of poloxamers and PLGA to confer stealth properties to the NPs to take advantage of the enhanced permeability and retention (EPR) effect. Different surface properties of NPs made up of bare PLGA and PLGA/poloxamer blend were confirmed by the different interactions of these NPs with serum proteins and also by their ability to be internalized by mesothelioma cell line. The uptake of PLGA/poloxamer NPs induces a persistent block in G0/G1 phase of the cell cycle up to 72 h, thus overcoming the drug tolerance phenomenon, normally evidenced with free CURC.

Combined anticancer therapies: an overview of the latest applications.

Tumor resistance and low drug efficacy prompt to investigate new therapeutic strategies that have high efficacy and low toxicity, especially for cancers with poor prognosis. This goal has been recently achieved using particular pharmaceutical combination or nanotechnologies to specifically deliver drugs at the tumor site. Novel combined treatments employ either naturally active ingredients or drugs already intended for other uses, with the aim to increase cell sensitivity to therapy and reduce drug toxicity. Combined treatments usually improve the overall therapeutic efficacy of the single drug. Drug-drug interactions allow synergistic effects. Several evidences indicate that synergy can be affected by drug-drug ratio and drug administration order. Therapeutic efficacy can be enhanced through drug entrapment in nanocarriers that allow a site-specific targeting, resulting in a build-up of the drug in the tumor with a significant toxicity reduction. Several studies investigated combined entrapment of two or more drugs each one characterized by different mechanisms of action. These nanosystems improve synergistic efficacy and could be a device to resolve toxicity and multi-drug resistance. Nano-encapsulation of anticancer agents by targeting specific tumor tissues significantly optimizes drug bioavailability, biocompatibility and therapeutic efficacy. The efficacy of these formulations results from receptor-mediated endocytosis and prolonged circulation time. Drug encapsulation also allows using limited final concentration while avoiding its activity within the blood circulation. In this review we report recent findings about novel combined treatment focusing on synergistic effects and mechanisms of action. We will also overview the latest drug delivery system and their therapeutic benefits in cancer treatment.

Efficacy of piroxicam plus cisplatin-loaded PLGA nanoparticles in inducing apoptosis in mesothelioma cells.

PURPOSE: Combined treatment based on cisplatin-loaded Poly(D,L-lactic-co-glicolic)acid (PLGA) nanoparticles (NP-C) plus the NSAID piroxicam was used as novel treatment for mesothelioma to reduce side effects related to cisplatin toxicity. METHODS: PLGA nanoparticles were prepared by double emulsion solvent evaporation method. Particle size, drug release profile and in vitro cellular uptake were characterized by TEM, DLS, LC/MS and fluorescence microscopy. MSTO-211H cell line was used to analyse NP-C biological efficacy by FACS and protein analysis. RESULTS: Cisplatin was encapsulated in 197 nm PLGA nanoparticles with 8.2% drug loading efficiency and 47% encapsulation efficiency. Cisplatin delivery from nanoparticles reaches 80% of total encapsulated drug in 14 days following a triphasic trend. PLGA nanoparticles in MSTO-211H cells were localized in the perinuclear space NP-C in combination with piroxicam induced apoptosis using a final cisplatin concentration 1.75 fold less than free drug. Delivered cisplatin cooperated with piroxicam in modulating cell cycle regulators as caspase-3, p53 and p21. CONCLUSIONS: Cisplatin loaded PLGA nanoparticles plus piroxicam showed a good efficacy in exerting cytotoxic activity and inducing the same molecular apoptotic effects of the free drugs. Sustained cisplatin release allowed to use less amount of drug, decreasing toxic side effects. This novel approach could represent a new strategy for mesothelioma treatment.

Functional and pharmacodynamic evaluation of metronomic cyclophosphamide and docetaxel regimen in castration-resistant prostate cancer.

AIM: The aim of our study was to investigate the association of docetaxel and metronomic cyclophosphamide (CYC) in castration-resistant prostate cancer (CRPC). MATERIALS & METHODS: CRPC xenografts were established with PC3 cells. Mice were treated with a combination of CYC (50 mg/kg/day) and docetaxel (10-30 mg/kg/week) or with docetaxel alone. Docetaxel plasma levels were analyzed in patients receiving the drug alone or combined with CYC. RESULTS: Metronomic CYC is an effective adjuvant in blocking tumor growth in vivo, with comparable efficacy and less toxic effects compared with docetaxel treatment. CYC acts by downregulating cell proliferation and inducing apoptosis thorough upregulation of p21 and inhibition of angiogenesis. Finally, CYC increases docetaxel plasma levels in patients. CONCLUSION: Metronomic CYC exerts anti-tumoral effects in an in vivo model of prostate cancer and in patients with CRPC, and also increases the bioavailability of docetaxel. These results explain the favorable toxicity and activity profiles observed in patients treated with this regimen.

Transcriptional profiling of endometriosis tissues identifies genes related to organogenesis defects.

Endometriosis is a common benign pathology, characterised by the presence of endometrial tissue outside the endometrial cavity with a prevalence of 10-15% in reproductive-aged women. The pathogenesis is not completely understood, and several theories have been proposed to explain the aetiology. Our group has recently described the presence of ectopic endometrium in a consistent number of human female foetuses analysed by autopsy, reinforcing the hypothesis that endometriosis may be generated by defects during the organogenesis of the female reproductive trait. Herein, in order to identify, at molecular level, changes involved in the disease, we compared the transcriptional profiling of ectopic endometrium with the corresponding eutopic one. Statistical analyses lead us to identify some genes specifically deregulated in the ectopic endometrium, that are involved in gonad developmental process or in wound healing process. Among them, we identified BMP4 and GREM1. BMP4 was never associated before to endometriosis and is involved in the mesoderm-Müllerian duct differentiation. GREM1 is needed for the initial step of the ureter growth and perhaps could possibly be involved in Müller ducts differentiation. These molecules might be related to the endometriosis aetiology since we showed that their expression is not related to the menstrual cycle phase both at RNA and at protein levels. These data support the theory that embryological defects could be responsible of the endometriosis generation.

In vitro model of stromal and epithelial immortalized endometriotic cells.

Endometriosis is a relatively common chronic gynecologic disorder that usually presents with chronic pelvic pain or infertility. It results from implantation of endometrial tissue outside the uterine cavity. Despite its frequency and its impact on quality of life, the understanding of pathogenesis of endometriosis remains incomplete and its treatment remains controversial. In this work, we established a suitable in vitro model system of immortalized human endometriotic cell line taking advantage of the human telomerase reverse transcriptase. The results demonstrate that these cells retain the natural characteristics of endometrial cells in term of phenotype and of functional expression of estrogen and progesterone receptors, without chromosomal abnormalities. In conclusion, these cells are potentially useful as an experimental model to investigate endometriosis biology.

Apoptosis induced by piroxicam plus cisplatin combined treatment is triggered by p21 in mesothelioma.

BACKGROUND: Malignant mesothelioma (MM) is a rare, highly aggressive tumor, associated to asbestos exposure. To date no chemotherapy regimen for MM has proven to be definitively curative, and new therapies for MM treatment need to be developed. We have previously shown in vivo that piroxicam/cisplatin combined treatment in MM, specifically acts on cell cycle regulation triggering apoptosis, with survival increase. METHODOLOGY/PRINCIPAL FINDINGS: We analyzed, at molecular level, the apoptotic increase caused by piroxicam/cisplatin treatment in MM cell lines. By means of genome wide analyses, we analyzed transcriptional gene deregulation both after the single piroxicam or cisplatin and the combined treatment. Here we show that apoptotic increase following combined treatment is mediated by p21, since apoptotic increase in piroxicam/cisplatin combined treatment is abolished upon p21 silencing. CONCLUSIONS/SIGNIFICANCE: Piroxicam/cisplatin combined treatment determines an apoptosis increase in MM cells, which is dependent on the p21 expression. The results provided suggest that piroxicam/cisplatin combination might be tested in clinical settings in tumor specimens that express p21.