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The development of new treatments for malignant melanoma, which has the worst prognosis among skin neoplasms, remains a challenge. The tumor microenvironment aids tumor cells to grow and resist to chemotherapeutic treatment. One way to mimic and study the tumor microenvironment is by using three-dimensional (3D) co-culture models (spheroids). In this study, a melanoma heterospheroid model composed of cancer cells, fibroblasts, and macrophages was produced by liquid-overlay technique using the agarose gel. The size, growth, viability, morphology, cancer stem-like cells population and inflammatory profile of tumor heterospheroids and monospheroids were analyzed to evaluate the influence of stromal cells on these parameters. Furthermore, dacarbazine cytotoxicity was evaluated using spheroids and two-dimensional (2D) melanoma model. After finishing the experiments, it was observed the M2 macrophages induced an anti-inflammatory microenvironment in heterospheroids; fibroblasts cells support the formation of the extracellular matrix, and a higher percentage of melanoma CD271 was observed in this model. Additionally, melanoma spheroids responded differently to the dacarbazine than the 2D melanoma culture as a result of their cellular heterogeneity and 3D structure. The 3D model was shown to be a fast and reliable tool for drug screening, which can mimic the in vivo tumor microenvironment regarding interactions and complexity. GRAPHIC ABSTRACT: [Image: see text]

Neglected tropical diseases (NTDs) are endemic to tropical and subtropical regions in Latin America, Africa and parts of Asia, representing a global public health problem. Despite affecting more than one billion people worldwide, the treatments for these diseases are highly toxic or even nonexistent, and it is usually necessary to treat the symptoms individually, which increases the burden to the healthcare systems. The development of nanomedicines against NTDs could provide effective solutions for managing the side effects and toxicities by minimizing the drug levels in healthy tissues while increasing the levels of drugs at the site of action. Thus, through the rational design of nano-scaled carriers incorporating drugs against neglected diseases, it is possible to promote selectivity, to minimize non-specific cellular toxicity and to reduce dosage, thereby, increasing the efficiency of the treatments. Here, we present the basic concepts, the main barriers for drug delivery in NTDs and the nanomedicine approaches in development to overcome them.

In this study, blended films of simvastatin (SIM) and resveratrol (RESV) were developed to improve the release of both poorly soluble drugs, aiming for the topical treatment of melanoma. RESV films containing different plasticizer content (polysorbate 80) exhibited residual crystals in the polymeric matrix of Eudragit®RL. The addition of the second drug (SIM) to blended films improved miscibility/solubility of RESV in the polymeric matrix, avoiding recrystallization of both drugs, as well as affecting intermolecular interactions of film components. Release investigations showed that RESVSIM-blended films provide higher drug release than RESV films and crystalline drugs in acidic buffer, but similar release to crystalline drugs in the same buffer at physiological pH. Cell culture studies revealed a cytotoxic synergistic effect of RESV and SIM in melanoma cell lines. The blended film RESVSIM3 and a blank film showed greater viability reduction in melanoma cell lines compared to a non-tumoral melanocyte cell line.

Silencing important genes related to tumorigenesis by RNA interference has emerged as promising alternative to cancer therapy. Targeted delivery of short interfering RNA (siRNA) to tumors is necessary, given the nucleic acid vulnerability in circulation. Here we used purified hybrid nanoparticles based on calcium phosphate for siRNA delivery against BCL-2 gene in murine breast tumors. Although biodistribution studies suggested that siRNA molecules carried by nanoparticles were found in heart, kidney and tumor, reduction in tumor volume and BCL-2 knockdown were observed. The results suggest that silencing antiapoptotic genes using siRNA-loaded hybrid nanoparticles is a powerful tool for cancer therapy.

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.

Titanium dioxide nanoparticles (TiO2 NP) are present in several daily use products, and the risks associated with their bioaccumulation must be stablished. Thus, an evaluation of several toxicological-related effects was conducted after intraperitoneal injection of TiO2 NPs in mice. Mice were divided into two groups, which received 2 mg kg−1 day−1 of TiO2 NPs or vehicle saline. Assessments of body and organ weight as well as biochemical, hematological, and histopathological analyses were performed in order to evaluate adverse effects. The results showed that treatment resulted in an increased visceral and abdominal fat deposition, as well as a mononuclear inflammatory infiltrates in the abdominal fat tissue. The TiO2 NPs induced significant decrease in the weight gain and splenomegaly. Additionally, TiO2 NP-treated mice showed altered hematological parameters and significant liver injuries, which were characterized by histopathological and biochemical changes. Our results also indicated that TiO2 NPs were absorbed and significantly accumulated in the spleen, liver, and kidney. These results showed the ability of TiO2 NPs to infiltrate different organs and to induce inflammation and liver and spleen damage with visceral fat accumulation. The data obtained are useful for the governmental authorities to legislate and implement regulations concerning the use and the production of this kind of material that might be hazardous to the living beings, as well as to the environment.

In this work in vivo experiments were conducted in order to characterize the biocompatibility of polyurethane nanoparticles (PU-NPs) after intraperitoneal (i.p.) and oral administration. Additionally, ex vivo assays were performed to assess human blood compatibility as well as in vitro assays to assess protein binding. Our results indicated that administration of three different concentrations of PU-NPs induced a significant increase in visceral fat accumulation after oral dosing. In addition, fat tissue of mice intraperitoneally treated with the highest concentration of nanoparticles showed diffuse mononuclear inflammatory infiltrate in the fat tissue. Histopathological assessment showed inflammatory infiltrate and hepatocyte vacuolization in the liver, inflammatory infiltration and vascular congestion in the lung and glomerular necrosis in the kidney. Hepatic enzymes related with liver function were significantly increased in both groups of mice treated with PU-NPs. The PU-NPs did not affect the human blood cells number as well as coagulation time but showed a susceptibility to bind in proteins commonly found in the blood stream. In addition, increased amounts of pro inflammatory cytokines in vivo, as well as ex vivo in human cells were observed. Further studies to establish the consequences of long-term exposure to PU-NPs are warranted.

In a previous study, we described a series of 28 aryl- and alkyl-substituted isothiouronium salts with antitumor activity and selectivity toward a leukemia cell line. Among the synthesized compounds, methyl (Z)-2-(isothioureidomethyl)-2-pentenoate hydrobromide (IS-MF08) showed conspicuous activity. In the present study, we investigated the mechanism of action of IS-MF08. Our results showed that its mechanism most likely is related with the membrane receptor Fas and subsequent activation of the extrinsic cell death pathway, triggered by a decrease in the levels of the anti-apoptotic protein Bcl-2 and caspase-8 and -3 cascade activation, causing DNA damage and mitotic arrest. IS-MF08 also caused an increase in intracellular ROS, endoplasmic reticulum (ER) stress, and mitochondrial membrane permeabilization, resulting in organelle degradation as an attempt to reestablish cell homeostasis. Furthermore, cells exposed to IS-MF08 combined to an autophagy inhibitor were less susceptible to compound's cytotoxicity, suggesting that autophagy makes part of its mechanism of action. These data support the hypothesis that IS-MF08 acts by the apoptosis extrinsic pathway and possibly by autophagy as mechanisms of cell death.

Nine types of solid lipid nanoparticle (SLN) formulations were produced using tripalmitin (TPM), glyceryl monostearate (GM) or stearic acid (SA), stabilized with lecithin S75 and polysorbate 80. Formulations were prepared presenting PI values within 0.25 to 0.30, and the physicochemical properties, stability upon storage and biocompatibility were evaluated. The average particle size ranged from 116 to 306 nm, with a negative surface charge around −11 mV. SLN presented good stability up to 60 days. The SLN manufactured using SA could not be measured by DLS due to the reflective feature of this formulation. However, TEM images revealed that SA nanoparticles presented square/rod shapes with an approximate size of 100 nm. Regarding biocompatibility aspects, SA nanoparticles showed toxicity in fibroblasts, causing cell death, and produced high hemolytic rates, indicating toxicity to red blood cells. This finding might be related to lipid type, as well as, the shape of the nanoparticles. No morphological alterations and hemolytic effects were observed in cells incubated with SLN containing TPM and GM. The SLN containing TPM and GM showed long-term stability, suggesting good shelf-life. The results indicate high toxicity of SLN prepared with SA, and strongly suggest that the components of the formulation should be analyzed in combination rather than separately to avoid misinterpretation of the results.

Superparamagnetic iron oxide nanoparticles (SPIONs) have been identified as a promising material for biomedical applications. These include as contrast agents for medical imaging, drug delivery and/or cancer cell treatment. The nanotoxicological profile of SPIONs has been investigated in different studies and the distribution of SPIONs in the human body has not been fully characterized. The aim of this study was to develop a physiologically-based pharmacokinetic (PBPK) model to predict the pharmacokinetics of SPIONs. The distribution and accumulation of SPIONs in organs were simulated taking into consideration their penetration through capillary walls and their active uptake by specialized macrophages in the liver, spleen and lungs. To estimate the kinetics of SPION uptake, a novel experimental approach using primary macrophages was developed. The murine PBPK model was validated against in vivo pharmacokinetic data, and accurately described accumulation in liver, spleen and lungs. After validation of the murine model, a similar PBPK approach was developed to simulate the distribution of SPIONs in humans. These data demonstrate the utility of PBPK modeling for estimating biodistribution of inorganic nanoparticles and represents an initial platform to provide computational prediction of nanoparticle pharmacokinetics. Fil: Henrique Silva, Adny. Universidade Federal de Santa Catarina; Brasil Fil: Lima, Enio Junior. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Vasquez Mansilla, Marcelo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Zysler, Roberto Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Mojica Pisciotti, Mary Luz. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Comisión Nacional de Energía Atómica. Centro Atómico Bariloche; Argentina Fil: Locatelli, Claudriana. Universidade do Alto Vale do Rio do Peixe; Brasil. Universidade do Oeste de Santa Catarina; Brasil Fil: Kumar Reddy Rajoli, Rajith. University of Liverpool; Reino Unido Fil: Owen, Andrew. University of Liverpool; Reino Unido Fil: Creczynski Pasa, Tânia Beatriz. Universidade Federal de Santa Catarina; Brasil Fil: Siccardi, Marco. University of Liverpool; Reino Unido

MicroRNA-21 (miR-21) has been described as upregulated in tissue and serum samples from patients with tumor diseases such as hepatocellular carcinoma. In addition, circulating miR-21 has been reported as a marker of necroinflammatory activity in patients with hepatitis C virus (HCV) and HCV-induced hepatocellular carcinoma (HCC). Thus, the expression of miR-21 by reverse transcription quantitative real-time PCR (RT-qPCR) in serum samples (n = 216) from patients with hepatic cirrhosis (n = 187) compared with control group (n = 29) was evaluated. Initially, peripheral blood was collected in tubes containing separating gel and clot activator and centrifuged at 820 × g for 10 min at room temperature. Then, the supernatants were transferred to new microtubes and the samples were centrifuged at 16,000 × g for 10 min to precipitate cell debris. Next, total serum RNA was isolated from 500 μL of serum from each sample and eluted in 50 μL of RNase-free water using a mirVanaTM PARISTM kit (AM1556, Ambion, Carlsbad, CA), according to the manufacturer's instructions. After that, total RNA quality obtained was evaluated by NanoVueTM Plus spectrophotometer (GE Healthcare, Buckinghamshire, UK) and the RT-qPCR was done using Taqman microRNA assays (Applied Biosystems, Foster City, CA). In the present work, the expression of miR-16 was not differentially expressed between healthy (Cq = 24.7 ± 3.0) and cirrhosis groups (Cq = 25.3 ± 3.0; P = 0.2741). Therefore, miR-16 was used as internal control to evaluate the expression of miR-21. The relative expression of miR-21 found was not statistically significant considering the control (1.0 ± 0.6) and cirrhosis groups (2.0 ± 3.5; P = 0.1478). The low expression of miR-21 indicates the patients did not yet develop a malignant disease or necroinflammatory activity. To better evaluate hepatic function, miR-34a, miR-122, and miR-885-5p were also analyzed, because these miRNAs have already been described as potential biomarkers for detection and assessment of liver diseases. The relative expressions found were significantly different for miR-34a (1.0 ± 1.5 vs 3.5 ± 8.1, P = 0.0077), miR-122 (1.0 ± 10.1 vs 1.2 ± 33.6, P < 0.0001) and miR-885-5p (1.0 ± 4.8 vs 1.9 ± 12.8, P = 0.0001). These miRNAs were found to be upregulated with fold-change for miR-34a, miR-122, and miR-885-5p of 4.1, 7.1, and 3.2, respectively. Due to the fact that these miRNAs were previously studied separately in independent studies, we applied a logistic regression model to obtain a miRNA panel not yet described. The logit model, logit(p = Cirrhosis) = 0.59 + 1.57 x miR-34a + 0.50 x miR-122 - 0.14 x miR-885-5p, was used to construct the ROC curve and, thus, to evaluate the diagnostic accuracy for the established miRNA panel. The area under the ROC curve (AUC) for the miRNA panel was 0.859 (95% confidence interval, 0.792-0.912; sensitivity: 84.8%; specificity: 73.7%; P < 0.0001), providing the high diagnostic accuracy for cirrhosis. A serum microRNA panel having considerable clinical value in cirrhosis diagnosis, chronic hepatitis viral, and hepatocellular carcinoma was found, thus allowing patients not to lose the window of treatment being benefited with a more appropriate therapy. Citation Format: Alex Evangelista Amaral, Júlia Cisilotto, Michele Patrícia Rode, Evelyn Winter, Adny Henrique Silva, Jelver Sierra-Restrepo, Leonardo de Lucca Schiavon, Tânia Beatriz Creczynski-Pasa. Serum microRNA panel to diagnose important liver diseases [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B78.

Several obstacles are encountered in conventional chemotherapy, such as drug toxicity and poor stability. Nanotechnology is envisioned as a strategy to overcome these effects and to improve anticancer therapy. Nanoemulsions comprise submicron emulsions composed of biocompatible lipids, and present a large surface area revealing interesting physical properties. Chalcones are flavonoid precursors, and have been studied as cytotoxic drugs for leukemia cells that induce cell death by different apoptosis pathways. In this study, we encapsulated chalcones in a nanoemulsion and compared their effect with the respective free compounds in leukemia and in non-tumoral cell lines, as well as in an in vivo model. Free and loaded-nanoemulsion chalcones induced a similar anti-leukemic effect. Free chalcones induced higher toxicity in VERO cells than chalcones-loaded nanoemulsions. Similar results were observed in vivo. Free chalcones induced a reduction in weight gain and liver injuries, evidenced by oxidative stress, as well as an inflammatory response. Considering the high toxicity and the side effects induced generally by all cancer chemotherapies, nanotechnology provides some options for improving patients’ life quality and/or increasing survival rates.

Chalcones, naturally occurring open-chain flavonoids abundant in plants, have demonstrated anticancer activity in multiple tumor cells. In a previous work, the potential anticancer activity of three naphthylchalcones named R7, R13 and R15 was shown. In this study, the mechanism of actions of these chalcones was originally shown. The chalcones presented concentration and time-dependent cytotoxicity. To determine the type of cell death induced by chalcones, we assessed a series of assays including measurements of the caspase-8, -9 and -12 activities, expression of important apoptosis-related genes and proteins, changes in the cell calcium concentration and cytochrome c release. The activities of caspase-8, -9 and -12 increased after the treatment of L1210 cells with the three compounds. Chalcones R7 and R13 induced an increase of pro-apoptotic proteins Bax, Bid and Bak (only chalcone R13), as well as a decrease in anti-apoptotic Bcl-2 expression. These chalcones also induced an increase in Fas and a decrease in p21 and p53 expression. Chalcone R15 seems to act by a different mechanism to promote cell death, as it did not change the mitochondrion-related proteins, nor did it induce the cytochrome c release. All compounds induced an increase in cell calcium concentration and an increase in CHOP expression, which together with an increase in caspase-12 activity, suggest that chalcones could induce an endoplasmic reticulum (ER) stress. Taken together, these results suggest that chalcones induce apoptosis by different pathways, being an interesting strategy to suggest for cancer therapy.