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Objectives: Candida albicans is a commensal organism and opportunistic pathogen associated both with superficial (mucosal and cutaneous) and systemic infections. Extensive use of antifungal agents has led to reduced susceptibility to the few existing drugs, which has encouraged the search for novel antifungal agents. Therefore, the present study investigated the antifungal activity of 2,6-bis[(E)-(4-pyridyl)methylidene]cyclohexanone (PMC) against C. albicans., Methods: The in vitro activity of PMC was evaluated against C. albicans. Additionally, an invertebrate infection model in Caenorhabditis elegans as well as two infected murine models of oral and systemic candidiasis were used to determine the antifungal efficacy of PMC in vivo., Results: Minimum inhibitory concentrations (MICs) of PMC ranged from 4-32μg/mL against nine clinical and two reference C. albicans isolates. Interestingly, PMC inhibited filamentation in vitro at subinhibitory concentrations similar to fluconazole. PMC also showed low toxicity against murine macrophages and human erythrocytes. In the invertebrate infection model, PMC was efficient in prolonging survival of C. elegans infected with C. albicans SC5314. Treatment with PMC was efficient both in murine models of systemic and oral candidiasis and was similar to that observed with conventional drug treatments (nystatin and fluconazole)., Conclusions: The results of this study indicate the therapeutic potential of PMC as it was able to inhibit filamentation of C. albicans in vitro. These alterations to the fungi by PMC resulted in a reduction of oral and systemic infection in mice. In conclusion, we present promising evidence of the anticandidal activity of PMC in vitro and in vivo., (Copyright © 2018. Published by Elsevier Ltd.)

Triazoles are interesting templates for novel chemotherapeutic drugs. We synthesized here 17 1,3,4-substituted-1,2,3-triazoles that differed in their 1'-substituent (variable alkyl chain lengths C3-C12), the 3'-substituent (no substituent, -methyl or -propyl) or the salt form obtained. Several of the compounds were cytotoxic (μM range) for tumor cells (HL-60, Jurkat, MCF-7, HCT-116), and when the effect was compared to non-transformed cells (Vero), selectivity ratios of up to 23-fold were obtained. To estimate the liability of these potential drug candidates for triggering neurotoxicity, we used the LUHMES cell-based NeuriTox assay. This test quantifies damage to the neurites of human neurons. The four most potent tumoricidal compounds were found to be neurotoxic in a concentration range similar to the one showing tumor cell toxicity. As the neurites of the LUHMES neurons were affected at >4-fold lower concentrations than the overall cell viability, the novel triazoles were classified as specific neurotoxicants. The structure-activity relationship (SAR) for neurotoxicity was sharply defined and correlated with the one for anti-neoplastic activity. Based on this SAR, two non-neurotoxic compounds were predicted, and testing in the NeuriTox assay confirmed this prediction. In summary, the panel of novel triazoles generated and characterized here, allowed to define structural features associated with cytotoxicity and neurotoxicity. Moreover, the study shows that potential neurotoxic side effects may be predicted early in drug development if highly sensitive test methods for neurite integrity are applied., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In seeking substitutions for the current Chagas disease treatment, which has several relevant side effects, new therapeutic candidates have been extensively investigated. In this context, a balanced interaction between mediators of the host immune response seems to be a key element for therapeutic success, as a proinflammatory microenvironment modulated by interleukin-10 (IL-10) is shown to be relevant to potentiate anti- Trypanosoma cruzi drug activity. This study aimed to identify the potential immunomodulatory activities of the anti- T. cruzi K777, pyronaridine (PYR), and furazolidone (FUR) compounds in peripheral blood mononuclear cells (PBMC) from noninfected (NI) subjects and chronic Chagas disease (CD) patients. Our results showed low cytotoxicity to PBMC populations, with 50% cytotoxic concentrations (CC 50 ) of 71.0 μM (K777), 9.0 μM (PYR), and greater than 20 μM (FUR). In addition, K777 showed no impact on the exposure index (EI) of phytohemagglutinin-stimulated leukocytes (PHA), while PYR and FUR treatments induced increased EI of monocytes and T lymphocytes at late stages of apoptosis in NI subjects. Moreover, K777 induced a more prominent proinflammatory response (tumor necrosis factor alpha-positive [TNF-α + ] CD8 + /CD4 + , gamma interferon-positive [IFN-γ + ] CD4 + /CD8 + modulated by interleukin-10-positive [IL-10 + ] CD4 + T/CD8 + T) than did PYR (TNF-α + CD8 + , IL-10 + CD8 + ) and FUR (TNF-α + CD8 + , IL-10 + CD8 + ). Signature analysis of intracytoplasmic cytokines corroborated the proinflammatory/modulated (K777) and proinflammatory (PYR and FUR) profiles previously found. In conclusion, the lead compound K777 may induce beneficial changes in the immunological profile of patients presenting the chronic phase of Chagas disease and may contribute to a more effective therapy against the disease., (Copyright © 2018 American Society for Microbiology.)

N-(2-butanoyloxyethyl)-4-(chloromethyl)-3-nitrobenzamide (NBCN) is a nitroaromatic bioreducible compound with cytotoxic effects in cancer cell lines. The aim of this work was to investigate the molecular mechanisms involved in cell death promoted by NBCN in HL60 cells. We observed that NBCN treatment increased intracellular ROS and reduced mitochondria membrane potential (ΔΨm). NBCN treatment also induced morphological changes, phosphatidylserine exposure, cell cycle arrest in G2/M-phase, DNA condensation and fragmentation, but it did not show cytotoxic effects on normal human peripheral blood mononuclear cells (PBMCs). NBCN-induced caspase 3- and 9-dependent DNA fragmentation, which was blocked by pretreatment with the broad-spectrum caspase inhibitor, z-VAD-fmk. Flow cytometry analysis demonstrated that NBCN also increased of the number of autophagic vesicles in HL60 cells, which was not observed when cells were pre-treated with bafilomycin A1. Taken together, these results indicate that NBCN triggered the mitochondrial apoptotic pathway and led to the onset of autophagic cell death, which contributed to its cytotoxic effects., (Copyright © 2017 Elsevier B.V. All rights reserved.)

BACKGROUND In a screen of extracts from plants and fungi to detect antileishmanial activity, we found that the ethyl acetate extract of the fungus Nectria pseudotrichia, isolated from the tree Caesalpinia echinata (Brazilwood), is a promising source of bioactive compounds. OBJECTIVES The aims of this study were to isolate and determine the chemical structures of the compounds responsible for the antileishmanial activity of the organic extract from N. pseudotrichia. METHODS Compounds were isolated by chromatographic fractionation using semi-preparative high-performance liquid chromatography, and their chemical structures were determined by analytical and spectral data and by comparison with published data. The antileishmanial activity of the isolated compounds was evaluated in intracellular amastigote forms of Leishmania (Viannia) braziliensis expressing firefly luciferase as reporter gene, and cytotoxicity was determined in Vero and THP-1 mammalian cell lines by MTT assay. FINDINGS Fractionation of the extract yielded seven compounds: 10-acetyl trichoderonic acid A (1), 6'-acetoxy-piliformic acid (2), 5',6'-dehydropiliformic acid (3), piliformic acid (4), hydroheptelidic acid (5), xylaric acid D (6), and cytochalasin D (7). Compounds 1, 2 and 3 are reported here for the first time. Compounds 1, 2, and 5 were more active, with IC50 values of 21.4, 28.3, and 24.8 µM, respectively, and showed low toxicity to Vero and THP-1 cells. MAIN CONCLUSIONS N. pseudotrichia produces secondary metabolites that are more toxic to intracellular amastigote forms of L. (V.) braziliensis than to mammalian cells.

The bioassay-guided fractionation of the ethyl acetate extract of the fungus Cochliobolus sp. highlighted leishmanicidal activity and allowed for anhydrocochlioquinone A (ANDC-A) isolation. MS, 1D and 2D NMR spectra of this compound were in agreement with those published in the literature. ANDC-A exhibited leishmanicidal activity with EC 50 value of 22.4 microgram/mL (44 mu M) and, when submitted to the microdilution assay against Gram-ositive and Gram-negative bacteria, showed a minimal inhibitory concentration against Staphylococcus aureus ATCC 25295 of 128 microgram/mL (248.7 mu M). It was also active against five human cancer cell lines, showing IC 50 values from 5.4 to 20.3 mu M. ANDC-A demonstrated a differential selectivity for HL-60 (SI 5.5) and THP-1 (SI 4.3) cell lines in comparison with Vero cells and was more selective than cisplatin and doxorubicin against MCF-7 cell line in comparison with human peripheral blood mononuclear cells. ANDC-A was able to eradicate clonogenic tumour cells at concentrations of 20 and 50 mu M and induced apoptosis in all tumour cell lines at 20 mu M. These results suggest that ANDC-A might be used as a biochemical tool in the study of tumour cells biochemistry as well as an anticancer agent with durable effects on tumours.

In the present work we describe the synthesis and antiproliferative evaluation of a focused library of 30 novel oxazolidines designed by modification of N-substituent, by ring variation, by alkyl variation or by extension of the structure. It was noted that carbamate and N,O-aminal groups were essential for activity. In general, replacement of the phenyl ring with pyridinyl was not tolerated. However, the introduction of a second phenyl ring with an appropriate spacer at the 3- or 4-position of the first phenyl ring generally enhanced the cytotoxic profile. Among all the prepared compounds, 24 was the most potent compound found in this class, being active on four of five cancer cell lines and it was 5-fold and 10-fold more potent than the lead compounds against HL60 and JURKAT cells, respectively. In addition, it showed relevant activity against MCF-7 and HCT-116 cells, which were resistant to lead. Moreover, 24 showed little antiproliferative activity against VERO, indicating low toxicity to normal cells. Thus, this compound has the potential to be developed as an anticancer agent., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Although overexpression of the brain and acute leukemia, cytoplasmic ( BAALC ) gene is associated with primary resistant disease and shorter relapse-free, disease-free, and overall survival in different subsets of acute myeloid leukemia (AML), little is known about its clinical impact in acute promyelocytic leukemia (APL). Using real-time reverse transcriptase polymerase chain reaction, we showed that BAALC expression is significantly lower in APL compared with other subsets of AML ( P < .001). We also demonstrated that BAALC overexpression was associated with shorter disease-free survival (DFS) (hazard ratio [HR], 4.43; 95% confidence interval [CI], 1.29-15.2; P = .018) in 221 consecutive patients (median age, 35 years; range, 18-82 years) with newly diagnosed APL homogeneously treated with all- trans retinoic acid and anthracycline-based chemotherapy. Cox proportional hazard modeling showed that BAALC overexpression was independently associated with shorter DFS in the total cohort (HR, 5.26; 95% CI, 1.52-18.2; P = .009) and in patients with high-risk disease (ie, those with initial leukocyte counts >10 × 10 9 /L) (HR, 5.3; 95% CI, 1.14-24.5; P = .033). We conclude that BAALC expression could be useful for refining risk stratification in APL, although this needs to be confirmed in independent cohorts., Competing Interests: Conflict-of-interest disclosure: The authors declare no competing financial interests.

Background: Current results regarding treatment outcomes in acute myeloid leukemia (AML) point to significant differences between low- and middle-income countries (LMIC) and high-income countries (HIC). Excluding well-known socioeconomic issues, genetic markers important for prognosis have not been properly incorporated into the clinical practice so far and their usefulness outside of well-controlled clinical trials remain unknown., Methods: Here, we assessed the clinical significance of the European LeukemiaNet (ELN) recommendations in 196 consecutive patients with AML in a real-life setting. All patients were younger than 60 years of age (49% male) and treated with conventional chemotherapy for induction and consolidation in three Brazilian Institutions that well represent Brazilian geographic and socioeconomic diversity., Findings: Multivariable analysis showed that ELN recommendations had a slight association with complete remission achievement (odds ratio: 0.74, 95% confidence interval, CI: 0.53-1.01; P=0.06), but were independently associated with poor overall survival (OS) (hazard ratio, HR: 1.3, 95% CI: 1.1-1.54; P=0.002), disease-free survival (DFS) (HR: 1.42, 95% CI: 1.03-1.95; P=0.028) and event-free survival (EFS) (HR: 1.24, 95% CI: 1.06-1.47; P=0.007), considering initial leukocyte counts and age as confounders. ELN recommendations had no impact on cumulative incidence of relapse (P=0.09)., Interpretation: Our results suggest that within the context of LMIC, the prognostic markers recommended by ELN may be useful to predict patient's clinical outcomes; however, the OS, DFS and EFS were shorter than the reported in Europe and US for the respective risk groups., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Luehea species are found in almost all Central and South American countries. The present work describes the phytochemical study, isolation, and structural characterisation of friedelin, β-friedelinol, lupeol, pseudotaraxasterol, β-sitosterol, betulinic acid, taraxasterol, (-)-epicatechin, β-sitosterol-3-O-β-d-glucopyranoside, and (+)-epicatechin-(4β→8)-epicatechin from stem barks of Luehea ochrophylla Mart. The structural identification of the isolated compounds was mainly performed by NMR analyses and comparison with the data from literature. These compounds were isolated for the first time in the genus Luehea, except β-sitosterol glucopyranoside, (-)-epicatechin, and lupeol. Hexane extract (HE) and dichloromethane (DF) and ethyl acetate (AF) fractions exhibited antiparasitic activity against amastigote (intracellular) and trypomastigote culture forms of Trypanosoma cruzi. The ethanol extract (EE), DF, and ethanol fraction (EF) exhibited considerable antifungal activity against Candida albicans. Moreover, extracts and fractions exhibited significant percentage of capture free radicals of 2,2-diphenyl-picrylhydrazyl (DPPH) when compared to the standard of ascorbic acid.

Paracoccidioidomycosis is the most prevalent systemic mycosis in Latin America, yet few therapeutic options exist. Our aim was to search for new compounds with high efficacy, low toxicity, shorter treatment time and affordable cost. We studied two synthetic 6-quinolinyl chalcones, 3b and 3e, to determine their effects on VERO cells, antifungal activity, survival curve, interaction with other drugs and phenotypic effects against several isolates of Paracoccidioides spp. In this study, we verified that the compounds were not toxic, exhibited superior in vitro activity compared with that shown by trimethoprim-sulfamethoxazole, and after 5 days of treatment, decreased the fungal cell viability by approximately 70%. Additionally, no interactions were observed between the tested compounds and other drugs. We also found that these compounds induced morphological changes, such as shriveling of cells, fragmentation of the plasma membrane and cytoplasmic disorganization in vitro. The changes observed by microscopy assays corroborate the observation made with propidium iodide, where the number of cells stained with the compounds was higher than that observed after amphotericin B treatment. We observed an increase in the efflux of K + and a loss of intracellular contents in cells treated with 3b and 3e, confirming their effects on fungal membranes. However, damage to the membrane was not associated with a decrease in membrane ergosterol levels. The experimental evidences showed no direct indications of cellular wall damage caused by these compounds. Thus, these results confirm the antifungal potential of 3b and 3e against Paracoccidioides spp. with possible action on the membrane.

Complexes [In(2Ac4oClPh)Cl 2 (MeOH)] (1), [In(2Ac4pFPh)Cl 2 (MeOH)] (2), [In(2Ac4pClPh)Cl 2 (MeOH)] (3) and [In(2Ac4pIPh)Cl 2 (MeOH)] (4) were obtained with N(4)-ortho-chlorophenyl-2-acetylpyridine thiosemicarbazone (H2Ac4oClPh), N(4)-para-fluorophenyl-2-acetylpyridine thiosemicarbazone (H2Ac4pFPh), N(4)-para-chlorophenyl-2-acetylpyridine thiosemicarbazone (H2Ac4pClPh) and N(4)-para-iodophenyl-2-acetylpyridine thiosemicarbazone (H2Ac4pIPh). Theoretical studies suggested that the coordinated methanol molecule can be easily replaced by DMSO used in the preparation of stock solutions, with the formation of [In(L)Cl 2 (DMSO)] (HL = thiosemicarbazonate ligand), and that the replacement of DMSO by water is unfavorable. However, for all complexes the displacement of one or two chloride ligands by water in aqueous solution is extremely favorable. The cytotoxic activity of the compounds was evaluated against HL-60, Jurkat and THP-1 leukemia and against MDA-MB-231 and HCT-116 solid tumor cell lines, as well as against Vero non-malignant cells. The cytotoxicity and selectivity indexes (SI) increased in several cases for the indium(iii) complexes in comparison with the free thiosemicarbazones. The antimicrobial activity of the compounds was investigated against Candida albicans, Candida dubliniensis, Candida lusitaniae and Candida parapsilosis. In many cases complexation resulted in a substantial increase of the antifungal activity. Complexes (1-4) were revealed to be very active against C. lusitaniae and C. dubliniensis. Structure-activity relationship (SAR) studies were carried out to identify the physico-chemical properties that might be involved in the antifungal action, as well as in the cytotoxic effect of the compounds against HL-60 cells. In both cases, correlations between the bioactivity and physico-chemical properties did not appreciably change when the chloride ligands in [In(L)Cl 2 (DMSO)] were replaced by water molecules, suggesting [In(L)Cl(H 2 O)(DMSO)] + or [In(L)(H 2 O) 2 (DMSO)] 2+ to be the species that interact with the biological media.

This study aimed to further investigate the cytotoxicity against tumor cell lines and several bacterial strains of Annona squamosa and its mode of action. Methanol extracts of A. squamosa leaves (ASL) and seeds (ASS) were used. ASL showed significant antibacterial activity against S. aureus, K. pneumoniae and E. faecalis with MIC values of 78, 78 and 39 µg/mL respectively. Moreover, ASL exhibited significant biofilm disruption, rapid time dependent kinetics of bacterial killing, increased membrane permeability and significantly reduced the cell numbers and viability. Regarding the cytotoxicity against tumor cell lines, ASS was more active against Jurkat and MCF-7 cells, with CI50 1.1 and 2.1 µg/mL, respectively. ASL showed promising activity against Jurkat and HL60, with CI50 4.2 and 6.4 µg/mL, respectively. Both extracts showed lower activity against VERO cells and reduced the clonogenic survival at higher concentrations (IC90) to MCF-7 and HCT-116 lineages. The alkaloids anonaine, asimilobine, corypalmine, liriodenine nornuciferine and reticuline were identified in extracts by UPLC-ESI-MS/MS analysis. This study reinforced that A. squamosa presents a remarkable phytomedicinal potential and revealed that its antimicrobial mechanism of action is related to bacterial membrane destabilization.

Ethnopharmacological Relevance: The leaves of Pereskia aculeata Miller (Cactaceae), known as Barbados gooseberry, are used as emollients and to treat skin wounds and inflammatory process in Brazilian traditional medicine., Aim of the Study: This study investigated the topical wound healing activity of gels containing the methanol extract (ME) and hexane fraction (HF) of the leaves of this plant in a model of excisional wound healing in mice., Material and Methods: Mice were anesthetized and excisional skin wounds were performed using a circular metal punch of 5mm diameter. Next, the animals were treated with 30µL of topical gel formulations containing the gel base (vehicle), HF 5% or ME 5%. The treatments were applied immediately after the injury and every 48h during 14 days. To verify the wound closure kinetics, a digital caliper was used throughout this period. Laser Doppler perfusion image (LDPI) was applied to evaluate the blood flow rate at the injury site. Microscopic examination of the skin tissues was performed by histopathological analysis with hematoxylin and eosin and Gomori trichrome staining. Picrosirius-red staining was also used for morphometric analysis for collagen quantification., Results: Both HF and ME markedly accelerated the closeness of the skin wounds; however the HF activity was more evident, as this fraction induced the increase of blood flow rate and collagen deposition when statistically compared to the vehicle. The mice skin treated with HF and ME also showed less fibroplasia, blood vessels and inflammatory cells on the last day of experiment, which indicated a more advanced wound healing process., Conclusions: As the wound healing process was considerably accelerated, especially by HF gel formulation, the results of this study not only contributed to better understand the ethnopharmacological application of P. acuelata leaves, but also encouraged further investigations on how to explore the potential uses of this plant in skin therapies., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Pseudomonas aeruginosa is an important pathogen in opportunistic infections in humans. The increased incidence of antimicrobial-resistant P. aeruginosa isolates has highlighted the need for novel and more potent therapies against this microorganism. Annona glabra is known for presenting different compounds with diverse biological activities, such as anti-tumor and immunomodulatory activities. Although other species of the family display antimicrobial actions, this has not yet been reported for A. glabra . Here, we investigated the antimicrobial activity of the ethyl acetate fraction (EAF) obtained from the leaf hydroalcoholic extract of A. glabra . EAF was bactericidal against different strains of P. aeruginosa . EAF also presented with a time- and concentration-dependent effect on P. aeruginosa viability. Testing of different EAF sub-fractions showed that the sub-fraction 32-33 (SF32-33) was the most effective against P. aeruginosa . Analysis of the chemical constituents of SF32-33 demonstrated a high content of flavonoids. Incubation of this active sub-fraction with P. aeruginosa ATCC 27983 triggered an endothermic reaction, which was accompanied by an increased electric charge, suggesting a high binding of SF32-33 compounds to bacterial cell walls. Collectively, our results suggest that A. glabra -derived compounds, especially flavonoids, may be useful for treating infections caused by P. aeruginosa .

The human topoisomerase IB inhibition and the antiproliferative activity of 3-(4-bromophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone HPyCT4BrPh alone and its copper(II) complex [Cu(PyCT4BrPh)Cl] was investigated. [Cu(PyCT4BrPh)Cl] inhibits both the DNA cleavage and religation step of the enzyme, whilst the ligand alone does not display any effect. In addition we show that coordination to copper(II) improves the cytotoxicity of HPyCT4BrPh against THP-1 leukemia and MCF-7 breast cancer cells. The data indicate that the copper(II) thiosemicarbazone complex may hit human topoisomerase IB and that metal coordination can be useful to improve cytotoxicity of this versatile class of compounds., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Complexes [Bi(2AcPh)Cl2]·0.5H2O (1), [Bi(2AcpClPh)Cl2] (2), [Bi(2AcpNO2Ph)Cl2] (3), [Bi(2AcpOHPh)Cl2]·2H2O (4), [Bi(H2BzPh)Cl3]·2H2O (5), [Bi(H2BzpClPh)Cl3] (6), [Bi(2BzpNO2Ph)Cl2]·2H2O (7) and [Bi(H2BzpOHPh)Cl3]·2H2O (8) were obtained with 2-acetylpyridine phenylhydrazone (H2AcPh), its -para-chloro-phenyl- (H2AcpClPh), -para-nitro-phenyl (H2AcpNO2Ph) and -para-hydroxy-phenyl (H2AcpOHPh) derivatives, as well as with the 2-benzoylpyridine phenylhydrazone analogues (H2BzPh, H2BzpClPh, H2BzpNO2Ph, H2BzpOHPh). Upon coordination to bismuth(III) antibacterial activity against Gram-positive and Gram-negative bacterial strains significantly improved except for complex (4). The cytotoxic effects of the compounds under study were evaluated on HL-60, Jurkat and THP-1 leukemia, and on MCF-7 and HCT-116 solid tumor cells, as well as on non-malignant Vero cells. In general, 2-acetylpyridine-derived hydrazones proved to be more potent and more selective as cytotoxic agents than the corresponding 2-benzoylpyridine-derived counterparts. Exposure of HCT-116 cells to H2AcpClPh, H2AcpNO2Ph and complex (3) led to 99% decrease of the clonogenic survival. The IC50 values of these compounds were three-fold smaller when cells were cultured in soft-agar (3D) than when cells were cultured in monolayer (2D), suggesting that they constitute interesting scaffolds, which should be considered in further studies aiming to develop new drug candidates for the treatment of colon cancer., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Complexes [Au(PyCT4BrPh)Cl]Cl (1), [Pt(PyCT4BrPh)Cl]0.5KCl (2), and [Pd(PyCT4BrPh)Cl]KCl (3) were obtained with 3-(4-bromophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4BrPh). Although complexes (2) and (3) did not exhibit potent cytotoxic activity, HPyCT4BrPh and its gold(III) complex (1) proved to be highly cytotoxic against HL-60 (human promyelocytic leukemia) and THP-1 (human monocytic leukemia) cells, and against MDA-MB 231 and MCF-7 (human breast adenocarcinoma) solid tumor cells. Except for HL-60 cells, upon coordination to gold(III) a 2- to 3-fold increase in the cytotoxic effect was observed. An investigation on the possible biological targets of the gold(III) complex was carried out. Complex (1) but not the free thiosemicarbazone inhibits the enzymatic activity of thioredoxin reductase (TrxR). The affinity of 1 for TrxR suggests metal binding to a selenol residue in the active site of the enzyme. While HPyCT4BrPh was inactive, 1 was able to inhibit topoisomerase IB (Topo IB) activity. Hence, inhibition of TrxR and Topo IB could contribute to the mechanism of cytotoxic action of complex (1).

Background: Chronic Chagas disease presents different clinical manifestations ranging from asymptomatic (namely indeterminate) to severe cardiac and/or digestive. Previous results have shown that the immune response plays an important role, although no all mechanisms are understood. Immunoregulatory mechanisms such as apoptosis are important for the control of Chagas disease, possibly affecting the morbidity in chronic clinical forms. Apoptosis has been suggested to be an important mechanism of cellular response during T. cruzi infection. We aimed to further understand the putative role of apoptosis in Chagas disease and its relation to the clinical forms of the disease., Methods: Apoptosis of lymphocytes, under antigenic stimuli (soluble T. cruzi antigens - TcAg) where compared to that of non-stimulated cells. Apoptosis was evaluated using the expression of annexin and caspase 3(+) by T cells and the percentage of cells positive evaluated by flow cytometry. In addition activation and T cell markers were used for the identification of TCD4(+) and TCD8(+) subpopulations. The presence of intracellular and plasma cytokines were also evaluated. Analysis of the activation status of the peripheral blood cells showed that patients with Chagas disease presented higher levels of activation determined by the expression of activation markers, after TcAg stimulation. PCR array were used to evaluate the contribution of this mechanism in specific cell populations from patients with different clinical forms of human Chagas disease., Results: Our results showed a reduced proliferative response associated a high expression of T CD4(+)CD62L(-) cells in CARD patients when compared with IND group and NI individuals. We also observed that both groups of patients presented a significant increase of CD4(+) and CD8(+) T cell subsets in undergoing apoptosis after in vitro stimulation with T. cruzi antigens. In CARD patients, both CD4(+) and CD8(+) T cells expressing TNF-α were highly susceptible to undergo apoptosis after in vitro stimulation. Interestingly, the in vitro TcAg stimulation increased considerably the expression of cell death TNF/TNFR superfamily and Caspase family receptors genes in CARD patients., Conclusions: Taken together, our results suggest that apoptosis may be an important mechanism for the control of morbidity in T. cruzi infection by modulating the expression of apoptosis genes, the cytokine environment and/or killing of effector cells.

Replication protein A (RPA) is an essential single-stranded DNA (ssDNA)-binding protein that initiates the DNA damage response pathway through protein-protein interactions (PPIs) mediated by its 70N domain. The identification and use of chemical probes that can specifically disrupt these interactions is important for validating RPA as a cancer target. A high-throughput screen (HTS) to identify new chemical entities was conducted, and 90 hit compounds were identified. From these initial hits, an anthranilic acid based series was optimized by using a structure-guided iterative medicinal chemistry approach to yield a cell-penetrant compound that binds to RPA70N with an affinity of 812 nm. This compound, 2-(3- (N-(3,4-dichlorophenyl)sulfamoyl)-4-methylbenzamido)benzoic acid (20 c), is capable of inhibiting PPIs mediated by this domain., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Fungi of the genus Paracoccidioides are responsible for paracoccidioidomycosis. The occurrence of drug toxicity and relapse in this disease justify the development of new antifungal agents. Compounds extracted from fungal extract have showing antifungal activity. Extracts of 78 fungi isolated from rocks of the Atacama Desert were tested in a microdilution assay against Paracoccidioides brasiliensis Pb18. Approximately 18% (5) of the extracts showed minimum inhibitory concentration (MIC) values ≤ 125.0 µg/mL. Among these, extract from the fungus UFMGCB 8030 demonstrated the best results, with an MIC of 15.6 µg/mL. This isolate was identified as Aspergillus felis (by macro and micromorphologies, and internal transcribed spacer, β-tubulin, and ribosomal polymerase II gene analyses) and was grown in five different culture media and extracted with various solvents to optimise its antifungal activity. Potato dextrose agar culture and dichloromethane extraction resulted in an MIC of 1.9 µg/mL against P. brasiliensis and did not show cytotoxicity at the concentrations tested in normal mammalian cell (Vero). This extract was subjected to bioassay-guided fractionation using analytical C18RP-high-performance liquid chromatography (HPLC) and an antifungal assay using P. brasiliensis. Analysis of the active fractions by HPLC-high resolution mass spectrometry allowed us to identify the antifungal agents present in the A. felis extracts cytochalasins. These results reveal the potential of A. felis as a producer of bioactive compounds with antifungal activity.

All-trans retinoic acid, a hydrophobic drug, has become one of the most successful examples of differentiation agents used for treatment of acute promyelocytic leukemia. On the other hand, histone deacetylase inhibitors, such as cholesteryl butyrate, present differentiating activity and.can potentiate action of drugs such as all-trans retinoic acid. Solid lipid nanoparticles represent a promising alternative for administration of hydrophobic drugs such as ATRA. This study aimed to develop, characterize, and evaluate the cytotoxicity of all-trans retinoic acid-loaded solid lipid nanoparticles for leukemia treatment. The influence of in situ formation of an ion pairing between all-trans retinoic acid and lipophilic amines on the characteristics of the particles (size, zeta potential, encapsulation efficiency) was evaluated. Cholesteryl butyrate, a butyric acid donor, was used as a component of the lipid matrix. In vitro activity on cell viability and distribution of cell cycle phases were evaluated for HL-60, Jurkat, and THP-1 cell lines. The encapsulation efficiency of all-trans retinoic acid in cholesteryl butyrate-solid lipid nanoparticles was significantly increased by the presence of the amine. Inhibition of cell viability by all-trans retinoic acid-loaded solid lipid nanoparticles was more pronounced than the free drug. Analysis of the distribution of cell cycle phases also showed increased activity for all-trans retinoic acid-loaded cholesteryl butyrate-solid lipid nanoparticles, with a clear increase in subdiploid DNA content. The ion pair formation in SLN containing cholesteryl butyrate can be explored as a simple and inexpensive strategy to improve the efficacy and bioavail-ability of ATRA in the treatment of the cancer and metabolic diseases in which this retinoid plays an important role.

Human cryptococcosis can occur as a primary or opportunistic infection and develop as an acute, subacute, or chronic, systemic infection involving different host organs. We evaluated the antifungal activity of thirteen compounds against Cryptococcus gattii and Cryptococcus neoformans in vitro, by assessing the toxicity of the compounds showing the greatest antifungal activity in VERO cells and murine macrophages. From these results, four compounds were considered promising for further studies because they displayed low cytotoxicity and significant antifungal activity. The heterocyclic compounds 1b, 1c, 1d, and 1m have antifungal activity levels between that of amphotericin B and fluconazole in vitro. The death curve of Cryptococcus spp. treated with these four compounds was similar to the curve obtained for amphotericin B, in that we observed a significant reduction in cell viability within the first 24 h of treatment. Additionally, we found that there was no effect when these compounds were combined with amphotericin and fluconazole, except for 1c, which antagonized the effect of amphotericin B against C. gattii, also reflected in the reduction of the post-antifungal effect (PAFE); however, this interaction did not alter the ergosterol content. The results shown in this paper reveal the discovery of novel thiazole compounds, which are easy to synthesize, and with potentially exhibit antifungal activity, and display low cytotoxicity in normal mammalian cells. These compounds can be used as prototypes for the design of new antifungal drugs against C. gattii and C. neoformans., (Copyright © 2015 Elsevier Masson SAS. All rights reserved.)

Front-line treatment of acute promyelocytic leukaemia (APL) consists of all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy. In this setting, a comparison of idarubicin and daunorubicin has never been carried out. Two similar clinical trials using ATRA and chemotherapy for newly diagnosed APL were compared using matched-pair analysis. One was conducted by the PETHEMA/HOVON group with idarubicin and the other by the International Consortium on APL (IC-APL) using daunorubicin. Three hundred and fifty patients from the PETHEMA/HOVON cohort were matched with 175 patients in the IC-APL cohort, adjusting for the significantly unbalanced presenting features of the two entire cohorts. Complete remission (CR) rate was significantly higher in the PETHEMA/HOVON (94 %) than in the IC-APL cohort (85 %) (P = 0.002). The distribution of causes of induction failure and the time to achieve CR were similar in both cohorts. Patients who achieved CR had comparable cumulative incidence of relapse and disease-free survival rates, but lower overall and event-free survivals were observed in the IC-APL cohort, which was mainly due to a higher death rate during induction therapy. A higher death rate during consolidation therapy was also observed in the IC-APL. These results show that daunorubicin and idarubicin have similar antileukaemic efficacy in terms of primary resistance, molecular persistence, as well as molecular and haematological relapse rates when combined with ATRA in treatment of APL. However, a higher toxic death rate during induction and consolidation therapy was observed in the IC-APL cohort. This trial was registered at www.clinicaltrials.gov as #NCT00408278 [ClinicalTrials.gov].

New methods for evaluating the canine immune system are necessary, not only to monitor immunological disorders, but also to provide insights for vaccine evaluations and therapeutic interventions, reducing the costs of assays using dog models, and provide a more rational way for analyzing the canine immune response. The present study intended to establish an in vitro toll to assess the parasitological/immunological status of dogs, applicable in pre-clinical trials of vaccinology, prognosis follow-up and therapeutics analysis of canine visceral leishmaniasis. We have evaluated the performance of co-culture systems of canine Leishmania chagasi-infected macrophages with different cell ratios of total lymphocytes or purified CD4(+) and CD8(+) T-cells. Peripheral blood mononuclear cells from uninfected dogs were used for the system set up. Employing the co-culture systems of L. chagasi-infected macrophages and purified CD4(+) or CD8(+) T-cell subsets we observed a microenvironment compatible with the expected status of the analyzed dogs. In this context, it was clearly demonstrated that, at this selected T-cell:target ratio, the adaptive immune response of uninfected dogs, composed by L. chagasi-unprimed T-cells was not able to perform the in vitro killing of L. chagasi-infected macrophages. Our data demonstrated that the co-culture system with T-cells from uninfected dogs at 1:5 and 1:2 ratio did not control the infection, yielding to patent in vitro parasitism (≥ 80%), low NO production (≤ 5 μM) and IL-10 modulated (IFN-γ/IL-10 ≤ 2) immunological profile in vitro. CD4(+) or CD8(+) T-cells at 1:5 or 1:2 ratio to L. chagasi-infected macrophages seems to be ideal for in vitro assays. This co-culture system may have great potential as a canine immunological analysis method, as well as in vaccine evaluations, prognosis follow-up and therapeutic interventions., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Ethnopharmacological Relevance: Arrabidaea chica (Bignoniacea) has been used in popular medicine in Brazil to treat inflammation, skin diseases and leukemia. This work aimed to investigate the anti-inflammatory and antitumoral activities of the A. chica aqueous (AE) and ethanol (EE) extracts., Materials and Methods: The murine sponge model was used to evaluate the anti-inflammatory and antiangiogenic activities of AE and EE. Accumulation of neutrophil and macrophage in the implants were determined by assaying myeloperoxidase and N-acetyl-glucosaminidase activities and the neovascularization evaluated by the amount of hemoglobin present in the implant using the Drabkin method. The antitumoral activity was evaluated using the MTT colorimetric method against Jurkat, HL60 and MCF-7 cells. Semi-purified fractions F1-F4 from the EE extract were obtained by a liquid-liquid solvent extraction method and their in vitro anti-proliferative effects were also investigated., Results: Ethanol and aqueous extracts of A. chica decreased neutrophil accumulation and hemoglobin content in the sponge implants without altering the level of cytokines (IL-2, IL- 4, IL-5, IFN-γ, TNF-α and VEGF) and the albumin/globulin ratio in the serum of treated animals. There was no sign of toxicity (clinical, laboratory or histopathology). The ethanol extract presented antiproliferative activity (IC50 21.5-36.3 µg/mL) against HL60 and Jurkat cell lineages and proapoptotic activity at 50 µg/mL in HL60 cells. The fraction F1 also demonstrated significant antiproliferative activity (IC50 38.5 µg/mL) and proapoptotic activity against HL60 cells in a dose dependent manner., Conclusions: Aqueous and ethanol extracts of A. chica attenuate the inflammatory and angiogenic components of the subcutaneous fibrovascular tissue induced by the synthetic matrix in mice. In addition, the ethanol extract from Arrabidaea chica and its fraction F1 presented in vitro antiproliferative activity and could be useful for developing potential chemopreventive substances., (Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.)

The proteolytic enzymes from V. cundinamarcensis latex, (P1G10), display healing activity in animal models following various types of lesions. P1G10 or the purified isoforms act as mitogens on fibroblast and epithelial cells by stimulating angiogenesis and wound healing in gastric and cutaneous ulcers models. Based on evidence that plant proteinases act as antitumorals, we verified this effect on a murine melanoma model. The antitumoral effect analyzed mice survival and tumor development after subcutaneous administration of P1G10 into C57BL/6J mice bearing B16F1 low metastatic melanoma. Possible factors involved in the antitumoral action were assessed, i.e., cytotoxicity, cell adhesion and apoptosis in vitro, haemoglobin (Hb), vascular endothelial growth factor (VEGF), tumor growth factor-β (TGF-β), tumor necrosis factor-α (TNF-α) content and N-acetyl-glucosaminidase (NAG) activity. We observed that P1G10 inhibited angiogenesis measured by the decline of Hb and VEGF within the tumor, and TGF-β displayed a non-significant increase and TNF-α showed a minor non-significant reduction. On the other hand, there was an increase in NAG activity. In treated B16F1 cells, apoptosis was induced along with decreased cell binding to extracellular matrix components (ECM) and anchorage, without impairing viability.

Objectives: All-trans retinoic acid (ATRA) is one of the most successful examples of differentiation agents and histone deacetylase inhibitors, such as tributyrin (TB), are known for their antitumor activity and potentiating action of drugs, such as ATRA. Nanostructured lipid carriers (NLC) represent a promising alternative to the encapsulation of lipophilic drugs such as ATRA. This study aims to develop, characterize and evaluate the cytotoxicity of ATRA-TB-loaded NLC for cancer treatment., Methods: The influence of in situ formation of an ion pairing between ATRA and a lipophilic amine (benethamine) on the characteristics of NLC (size, zeta potential, encapsulation efficiency) was evaluated. TB, a butyric acid donor, was used as a component of the lipid matrix. In vitro activity on cell viability and distribution of cell cycle phases were evaluated for MCF-7, MDA-MB-231, HL-60 and Jurkat cell lines., Results: The presence of the amine significantly increased the encapsulation efficiency of ATRA in NLC. Inhibition of cell viability by TB-ATRA-loaded NLC was more pronounced than the free drug. Analysis of the distribution of cell cycle phases also showed increased activity for TB-ATRA-loaded NLC, with the clear effect of cell cycle arrest in G0/G1 phase transition. The presence of TB played an important role in the activity of the formulation., Conclusion: Taken together, these findings suggest that TB-ATRA-loaded NLC represents a promising alternative to intravenous administration of ATRA in cancer treatment.

Twenty-seven nitrated and non-nitrated compounds have been synthesized and tested for their growth inhibitory activity on three human cancer cells lines. Fourteen compounds were able to inhibit more than 50% of the growth of at least one of the cancer cell lines and five compounds exhibited high antiproliferative activity on human cancer cell lines (IC50 < 8.5 μM). The cytotoxicity of the compounds on Vero cell line was established in vitro to evaluate the selectivity. All active compounds have a good leaving group (bromide or chloride) at the benzylic position, indicating that the mechanism of action of these compounds is related to their alkylating properties. Two compounds (3 and 24) were selected for further studies in mice with Ehrlich solid tumors and display significant antitumor effects in vivo.

Background: Human T-lymphotropic virus 1 (HTLV-1) has been associated with leukemia/lymphoma (ATL) and myelopathy/tropical spastic paraparesis (HAM/TSP), in addition to other inflammatory diseases as well as infection complications. Therapeutic approaches for HTLV-1-related pathologies are limited. The labdane diterpene myriadenolide (AMY) is a natural product that exhibit biological activities, such as anti-inflammatory and antiviral activity as reported for HIV and herpesvirus., Results: We demonstrated that this natural product was able to inhibit the expression of gag-pol mRNA and substantially reduced the expression of the structural proteins p19 and gp46. Comparison of treated and untreated cells shows that AMY alters both the morphology and the release of viral particles. The Atomic Force Microscopy assay showed that the AMY treatment reduced the number of particles on the cell surface by 47%., Conclusion: We demonstrated that the labdane diterpene myriadenolide reduced the expression of the structural proteins and the budding of viral particles, besides induces altered morphogenesis of HTLV-1, conferring on AMY a new antiviral activity that may be useful for the development of new compounds with specific anti-HTLV-1 activity.

Activating internal tandem duplication (ITD) mutations in the fms-like tyrosine kinase 3 (FLT3) gene (FLT3-ITD) are associated with poor outcome in acute myeloid leukemia, but their prognostic impact in acute promyelocytic leukemia (APL) remains controversial. Here, we screened for FLT3-ITD mutations in 171 APL patients, treated with all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy. We identified FLT3-ITD mutations in 35 patients (20 %). FLT3-ITD mutations were associated with higher white blood cell counts (P < 0.0001), relapse-risk score (P = 0.0007), higher hemoglobin levels (P = 0.0004), higher frequency of the microgranular morphology (M3v) subtype (P = 0.03), and the short PML/RARA (BCR3) isoform (P < 0.0001). After a median follow-up of 38 months, FLT3-ITD(positive) patients had a lower 3-year overall survival rate (62 %) compared with FLT3-ITD(negative) patients (82 %) (P = 0.006). The prognostic impact of FLT3-ITD on survival was retained in multivariable analysis (hazard ratio: 2.39, 95 % confidence interval [CI] 1.17-4.89; P = 0.017). Nevertheless, complete remission (P = 0.07), disease-free survival (P = 0.24), and the cumulative incidence of relapse (P = 0.94) rates were not significantly different between groups. We can conclude that FLT3-ITD mutations are associated with several hematologic features in APL, in particular with high white blood cell counts. In addition, FLT3-ITD may independently predict a shorter survival in patients with APL treated with ATRA and anthracycline-based chemotherapy.

Replication Protein A is the primary eukaryotic ssDNA binding protein that has a central role in initiating the cellular response to DNA damage. RPA recruits multiple proteins to sites of DNA damage via the N-terminal domain of the 70 kDa subunit (RPA70N). Here we describe the optimization of a diphenylpyrazole carboxylic acid series of inhibitors of these RPA-protein interactions. We evaluated substituents on the aromatic rings as well as the type and geometry of the linkers used to combine fragments, ultimately leading to submicromolar inhibitors of RPA70N protein-protein interactions.

One of the hallmarks of Alzheimer's disease (AD) in the brain are amyloid-β (Aβ) plaques, and metal ions such as copper(II) and zinc(II) have been shown to play a role in the aggregation and toxicity of the Aβ peptide, the major constituent of these extracellular aggregates. Metal binding agents can promote the disaggregation of Aβ plaques, and have shown promise as AD therapeutics. Herein, we describe the syntheses and characterization of an acetohydrazone (8-H2QH), a thiosemicarbazone (8-H2QT), and a semicarbazone (8-H2QS) derived from 8-hydroxyquinoline. The three compounds are shown to be neutral at pH7.4, and are potent antioxidants as measured by a Trolox Equivalent Antioxidant Capacity (TEAC) assay. The ligands form complexes with Cu(II), 8-H2QT in a 1:1 metal:ligand ratio, and 8-H2QH and 8-H2QS in a 1:2 metal:ligand ratio. A preliminary aggregation inhibition assay using the Aβ1-40 peptide showed that 8-H2QS and 8-H2QH inhibit peptide aggregation in the presence of Cu(II). Native gel electrophoresis/Western blot and TEM images were obtained to give a more detailed picture of the extent and pathways of Aβ aggregation using the more neurotoxic Aβ1-42 in the presence and absence of Cu(II), 8-H2QH, 8-H2QS and the drug candidate PBT2. An increase in the formation of oligomeric species is evident in the presence of Cu(II). However, in the presence of ligands and Cu(II), the results match those for the peptide alone, suggesting that the ligands function by sequestering Cu(II) and limiting oligomer formation in this assay., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Metal complexes with 2-acetylpyridine-N(4)-orthochlorophenylthiosemicarbazone (H2Ac4oClPh) were assayed for their cytotoxicity against MCF-7 breast adenocarcinoma and HT-29 colon carcinoma cells. The thiosemicarbazone and most of the complexes were highly cytotoxic. H2Ac4oClPh and its gallium(III) and tin(IV) complexes did not show any inhibitory activity against thioredoxin reductase (TrxR) and glutathione reductase (GR). The palladium(II), platinum(II) and bismuth(III) complexes inhibited TrxR at micromolar concentrations but not GR. The antimony(III) and gold(III) complexes strongly inhibited TrxR at submicromolar doses with GR inhibition at higher concentrations. The selectivity of these complexes for TrxR suggests metal binding to a selenol residue in the active site of the enzyme. TrxR inhibition is likely a contributing factor to the mode of action of the gold and antimony derivatives., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

The KMT2E (MLL5) gene encodes a histone methyltransferase implicated in the positive control of genes related to haematopoiesis. Its close relationship with retinoic acid-induced granulopoiesis suggests that the deregulated expression of KMT2E might lead acute promyelocytic leukaemia (APL) blasts to become less susceptible to the conventional treatment protocols. Here, we assessed the impact of KMT2E expression on the prognosis of 121 APL patients treated with ATRA and anthracycline-based chemotherapy. Univariate analysis showed that complete remission (P = 0·006), 2-year overall survival (OS) (P = 0·005) and 2-year disease-free survival (DFS) rates (P = 0·037) were significantly lower in patients with low KMT2E expression; additionally, the 2-year cumulative incidence of relapse was higher in patients with low KMT2E expression (P = 0·04). Multivariate analysis revealed that low KMT2E expression was independently associated with lower remission rate (odds ratio [OR]: 7·18, 95% confidence interval [CI]: 1·71-30·1; P = 0·007) and shorter OS (hazard ratio [HR]: 0·27, 95% CI: 0·08-0·87; P = 0·029). Evaluated as a continuous variable, KMT2E expression retained association with poor remission rate (OR: 10·3, 95% CI: 2·49-43·2; P = 0·001) and shorter survival (HR: 0·17, 95% IC: 0·05-0·53; P = 0·002), while the association with DFS was of marginal significance (HR: 1·01; 95% CI: 0·99-1·02; P = 0·06). In summary, low KMT2E expression may predict poor outcome in APL patients., (© 2014 John Wiley & Sons Ltd.)

Stapled helix peptides can serve as useful tools for inhibiting protein-protein interactions but can be difficult to optimize for affinity. Here we describe the discovery and optimization of a stapled helix peptide that binds to the N-terminal domain of the 70 kDa subunit of replication protein A (RPA70N). In addition to applying traditional optimization strategies, we employed a novel approach for efficiently designing peptides containing unnatural amino acids. We discovered hot spots in the target protein using a fragment-based screen, identified the amino acid that binds to the hot spot, and selected an unnatural amino acid to incorporate, based on the structure-activity relationships of small molecules that bind to this site. The resulting stapled helix peptide potently and selectively binds to RPA70N, does not disrupt ssDNA binding, and penetrates cells. This peptide may serve as a probe to explore the therapeutic potential of RPA70N inhibition in cancer.

We have previously reported the discovery of cytotoxic and pro-apoptotic hit compound 1,1-dimethylethyl (S)- 2,2-dimethyl-4-[(3-nitrophenoxy)methyl]-3-oxazolidinecarboxylate 1 against leukemia cells. In the present work we describe the synthesis of 25 derivatives of this hit varying the substituent at ring or stereochemistry of the oxazolidine ring and evaluated them against human cancer cells lines. Six compounds exerted significant activity against HL60 promyelocytic leukemia cells with IC50 in low micromolar range (4-18 μM) and three compounds displayed activity against MDA-MB231 breast cancer cells (25-37 μM). In vitro cytotoxicity on normal cells PBMC (human peripheral blood mononuclear cells) was also evaluated. Compounds 7e (p-NO2, S) and 7m (p-COOCH3, S) showed good antiproliferative activity against HL60 (4 and 5 μM) and MDA-MB231 (37 and 25 μM) without affecting lymphocyte proliferation in PBMC, indicating low toxicity to normal cells. Besides, compound 7e induced DNA fragmentation on about 100% of HL60 cells at 50 μM. In this case, it was more potent than 7m and lead 1. This indicated that compound 7e has a great pro-apoptotic potential.

Species of the genus Lacistema are traditionally used by Brazilian and Peruvian indigenous communities. The present study investigated the in vitro antileishmanial activity against several Leishmania species, cytotoxicity in murine peritoneal macrophages, antiproliferative activity against HL60 and Jurkat cells, and antibacterial activities against seven bacteria strains of the aerial parts of the methanolic crude extract and fractions of Lacistema pubescens. In addition, their chemical profile was also evaluated. Hexane fraction showed the most significant IC50 values against all promastigotes of Leishmania species tested, except for L. chagasi (IC50 = 4.2 µg/mL for L. major and IC50 = 3.5 µg/mL for L. amazonensis). This fraction also exhibited a strong activity against amastigotes of L. amazonensis (IC50 = 6.9 µg/mL). The antiproliferative activity was also observed for methanolic extract and hexane fraction with IC50 = 47.2 µg/mL and IC50 = 39.7 µg/mL for HL60, respectively. Regarding the antimicrobial activity, the overall antibacterial activity was not very significative. Phytol and sitosterol were identified in the methanolic extract. Additionally, previous studies also revealed the presence of those compounds in the hexane fraction. Among other compounds, phytol and sitosterol were probably involved in the antileishmanial and cytotoxicity activities observed in this study.

Hypnophilin (HNP) is a sesquiterpene that is isolated from Lentinus cf. strigosus and has cytotoxic activities. Here, we studied the calcium signaling and cytotoxic effects of HNP in UACC-62 cells, a human skin melanoma cell line. HNP was able to increase the intracellular calcium concentration in UACC-62 cells, which was blocked in cells stimulated in Ca(2+) -free media. HNP treatment with BAPTA-AM, an intracellular Ca(2+) chelator, caused an increase in calcium signals. HNP showed cytotoxicity against UACC-62 cells in which it induced DNA fragmentation and morphological alterations, including changes in the nuclear chromatin profile and increased cytoplasmatic vacuolization, but it had no effect on the plasma membrane integrity. These data suggest that cytotoxicity in UACC-62 cells, after treatment with HNP, is associated with Ca(2+) influx. Together, these findings suggest that HNP is a relevant tool for the further investigation of new anticancer approaches., (© 2013 Wiley Periodicals, Inc.)

[Cu(HL)Cl2] complexes of chalcone-derived thiosemicarbazones were obtained with 3-phenyl-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCTPh), complex (1), 3-(4-chlorophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4ClPh), complex (2), 3-(4-bromophenyl)-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4BrPh), complex (3), and 3-(4-nitrophenyl-1-pyridin-2-ylprop-2-en-1-one thiosemicarbazone (HPyCT4NO2Ph), complex (4). 1-3 showed interaction with bovine serum albumin (BSA) and deoxyribonucleic acid from calf thymus (CT-DNA). The cytotoxic activities of the thiosemicarbazones and complexes (1-4) were tested against HL60 (wild type human promyelocytic leukemia), Jurkat (human immortalized line of T lymphocyte), MDA-MB 231 (human breast carcinoma) and HCT-116 (human colorectal carcinoma) tumor cell lineages. Upon coordination to copper(II) cytotoxicity significantly increased in Jurkat, MDA-MB 231 and HCT-116 cells. Unlike the free thiosemicarbazones, 1-4 induced DNA fragmentation in solid tumor cells indicating their pro-apoptotic potential., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)

Cecropia pachystachya is widely used in the traditional medicine as anti-inflammatory, antitusive, expectorant, antiasthmatic and hypoglycemic. It is also commercially available to treat skin cancer. To validate some of the popular uses of this species, its methanol leaves extract (CPM) was tested for anti-inflammatory, antinociceptive and cytotoxic effects. The anti-inflammatory activity was evaluated by croton oil-induced ear edema test. When used orally, the anti-inflammatory effect of CPM at 300 mg/kg was similar to that of indomethacin with 53% inhibition of the ear edema. Also, results on topical treatment were similar to that of dexamethasone with 83% inhibition of the edema. To evaluate the antinociceptive activity, acetic acid-induced writhing and formalin-induced pain tests were employed. CPM (100 and 300 mg/kg) reduced the number of writhing by 61% and 67%, respectively. In both doses, the activity was comparable to the reference drug, indomethacin. The oral administration of CPM was ineffective in the first phase of formalin test but exhibited great effects on the second phase decreasing the licking time by 85% at 300 mg/kg. The cytotoxic potential of CPM was also investigated against HL60, HL60.bcl2 and Jurkat tumor cell lines and showed an inhibition of more than 50% of cell proliferation. The flavones orientin and isoorientin were detected in CPM., (Copyright © 2012 John Wiley & Sons, Ltd.)

Lapachol was chemically modified to obtain its thiosemicarbazone and semicarbazone derivatives. These compounds were tested for antimicrobial activity against several bacteria and fungi by the broth microdilution method. The thiosemicarbazone and semicarbazone derivatives of lapachol exhibited antimicrobial activity against the bacteria Enterococcus faecalis and Staphylococcus aureus with minimal inhibitory concentrations (MICs) of 0.05 and 0.10 µmol/mL, respectively. The thiosemicarbazone and semicarbazone derivatives were also active against the pathogenic yeast Cryptococcus gattii (MICs of 0.10 and 0.20 µmol/mL, respectively). In addition, the lapachol thiosemicarbazone derivative was active against 11 clinical isolates of Paracoccidioides brasiliensis, with MICs ranging from 0.01-0.10 µmol/mL. The lapachol-derived thiosemicarbazone was not cytotoxic to normal cells at the concentrations that were active against fungi and bacteria. We synthesised, for the first time, thiosemicarbazone and semicarbazone derivatives of lapachol. The MICs for the lapachol-derived thiosemicarbazone against S. aureus, E. faecalis, C. gattii and several isolates of P. brasiliensis indicated that this compound has the potential to be developed into novel drugs to treat infections caused these microbes.

Thanks to modern treatment with all-trans retinoic acid and chemotherapy, acute promyelocytic leukemia (APL) is now the most curable type of leukemia. However, this progress has not yielded equivalent benefit in developing countries. The International Consortium on Acute Promyelocytic Leukemia (IC-APL) was established to create a network of institutions in developing countries that would exchange experience and data and receive support from well-established US and European cooperative groups. The IC-APL formulated expeditious diagnostic, treatment, and supportive guidelines that were adapted to local circumstances. APL was chosen as a model disease because of the potential impact on improved diagnosis and treatment. The project included 4 national coordinators and reference laboratories, common clinical record forms, 5 subcommittees, and laboratory and data management training programs. In addition, participating institutions held regular virtual and face-to-face meetings. Complete hematological remission was achieved in 153/180 (85%) patients and 27 (15%) died during induction. After a median follow-up of 28 months, the 2-year cumulative incidence of relapse, overall survival (OS), and disease-free survival (DFS) were 4.5%, 80%, and 91%, respectively. The establishment of the IC-APL network resulted in a decrease of almost 50% in early mortality and an improvement in OS of almost 30% compared with historical controls, resulting in OS and DFS similar to those reported in developed countries.

Objectives: Sodium salicylate (NaSal) can disturb cell viability by affecting the activity of multiple cellular molecules. In this work, we investigated the involvement of stress-responsive kinase GCN2 in regulating cell death and expression of stress genes in mouse embryonic fibroblasts (MEFs) upon exposure to NaSal., Methods: Cell viability was assayed using the 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide (MTT) method, and apoptosis was evaluated by annexin V and propidium iodide staining. A polymerase chain reaction (PCR) array approach was used to analyse differential expression of a panel of 84 endoplasmic reticulum (ER) stress-associated genes. Gene reporter assays were carried out to determine activity of ER stress element (ERSE), and the protein levels of activating transcription factor 6 (ATF6) and C/EBP homologous protein (CHOP) were determined by western blot., Key Findings: NaSal treatment resulted in reduction of cellular viability and induction of apoptosis in wild-type but not Gcn2(-/-) cells. Many genes with important functions in protein synthesis/degradation, transcriptional regulation and apoptosis were induced by NaSal and most of these were dependent on GCN2. The activation of ERSE within Ddit3 and the production of CHOP and ATF6 induced by NaSal required GCN2., Conclusions: Our data provide evidence for the involvement of GCN2 in apoptosis and gene expression triggered by NaSal, and contributes to the understanding of molecular events occurring in NaSal-treated cells., (© 2012 The Authors. JPP © 2012. Royal Pharmaceutical Society.)

While several mechanisms of immunoregulation have been demonstrated for hookworm and other neglected tropical infections, the influence of apoptosis in the immunomodulation of hookworm infection is still poorly understood. In this study, we demonstrate the cytotoxic and pro-apoptotic activity of hookworm antigens in Jurkat T cells, mesenteric lymph nodes lymphocytes of healthy and hookworm-infected hamsters and during human natural infection. Our results showed that in vitrostimulation of Jurkat T cells with antigens induces a significant decrease of cell viability leading to a relevant increase of apoptotic cells. Similar results were also observed in experimental conditions, for both healthy and hookworm-infected hamsters` lymphocytes. Flow cytometric analysis demonstrated that hookworm-infected patients presented a significant increase of CD4+, CD8+, and CD19+lymphocytes in early and/or late apoptosis when compared with non-infected individuals. The downmodulation of TNF receptors, as well as the up-regulation of the pro-apoptotic genes belonging to the BCL-2 and P53 families, suggest that hookworm antigens induced apoptosis by an intrinsic mitochondrial pathway, acting as a sophisticated strategy to safeguard parasite long-term survival in their hosts.