A mechanistic insight into the anti-metastatic role of the prostate specific antigen

AimSince its discovery Prostate Specific Antigen (PSA), also referred to as kallikrein-3 (KLK3), has been used as standard circulating biomarker for prostate cancer (PCa). However, its specificity remains not adequate and its mechanism of action still elusive. Therefore, deciphering PSA role throughout PCa-pathobiology would be relevant in improving both cancer diagnosis and outcome prediction. We investigated the possible role played by PSA on/in the tumor microenvironment and over the first steps of cancer invasion.MethodsFresh PCa-specimens and cell lines were used for ex-vivo/in-vitro invasion assays and assessment of prostate tissue-PSA (tPSA), type 1 collagen (COL1A1) and ß1-integrin expression. Tissue Cancer Genome Atlas (TCGA) and Decipher® datasets were considered to estimate tPSA clinical relevance.ResultsA more precise, inverse, correspondence between tPSA and clinical/pathological parameters was found than for circulating PSA. KLK3 combined with Gleason grade and pathologic stage, better predicted cancer-related mortality. Consistently, we demonstrated that PSA inhibits prostate extracellular-matrix (ECM) invasion by PCa cells. As for the mechanism of action, we provided novel information that PSA is able to cleave COL1A1, a main component of the ECM. Finally, ß1-integrin, a crucial COL1A1 transducing-receptor involved in tumor adhesion/invasion, resulted to be downregulated in PCa specimens with higher levels of tPSA.ConclusionsBy interfering with type 1 collagen and its downstream targets, PSA may hamper adhesion and path of the cancer cells through ECM and their migration ability, thus explaining the inverse correlation highlighted between prostate tPSA levels and clinically significant disease.     

Dithiocarbamate prodrugs activated by prostate specific antigen to target prostate cancer

Disulfiram in conjunction with copper has been shown to be a potent anticancer agent. However, disulfiram’s therapeutic potential in prostate cancer is hindered by off-target effects due to its reactive and nucleophilic thiol-containing component, diethyldithiocarbamate (DTC). To minimize undesirable reactivity, we have strategically blocked the thiol moiety in DTC with a cleavable p-aminobenzyl (pAB) group linked to peptide substrates recognized by prostate specific antigen (PSA). Here we report the synthesis and evaluation in cancer cell models of two PSA-activatable prodrugs: HPD (Ac-HSSKLQL-pAB-DTC and RPD (RSSYYSL-pAB-DTC). In vitro exposure to PSA was found to trigger activation of HPD and RPD to release diethyldithiocarbamate, and both prodrugs were found to induce toxicity in prostate cancer cells, with HPD showing the most promising selectivity. With copper supplementation, the IC₅₀ of HPD was 1.4 µM in PSA-expressing LNCaP cells, and 11 µM in PC3 cells that do not express PSA. These studies demonstrate the utility of using peptide recognition handles to direct the activity of dithiocarbamate prodrugs for selective cytotoxicity of cancer cells.     

Piper crocatum Ruiz & Pav. ameliorates wound healing through p53, E-cadherin and SOD1 pathways on wounded hyperglycemia fibroblasts

IntroductionPiper crocatum Ruiz & Pav (P. crocatum) has been reported to accelerate the diabetic wound healing process empirically. Some studies showed the benefits of P. crocatum in treating various diseases but its mechanisms in diabetic wound healing have never been reported. In the present study we investigated the diabetic wound healing activity of the active fraction of P. crocatum on wounded hyperglycemia fibroblasts (wHFs).MethodsBioassay-guided fractionation was performed to get the most active fraction. The selected active fraction was applied to wHFs within 72 h incubation. Mimicking a diabetic condition was done using basal glucose media containing an additional 17 mMol/L D-glucose. A wound was simulated via the scratch assay. The collagen deposition was measured using Picro-Sirius Red and wound closure was measured using scratch wound assay. Underlying mechanisms through p53, αSMA, SOD1 and E-cadherin were measured using western blotting.ResultsWe reported that F_IV is the most active fraction of P. crocatum. We confirmed that F_IV\(7.81 µg/ml, 15.62 µg/ml, 31.25 µg/ml, 62.5 µg/ml, and 125 µg/ml) induced the collagen deposition and wound closure of wHFs. Furthermore, F_IV treatment (7.81 µg/ml, 15.62 µg/ml, 31.25 µg/ml) down-regulated the protein expression level of p53 and up-regulated the protein expression levels of αSMA, E-cadherin, and SOD1.Discussion/conclusionsOur findings suggest that ameliorating collagen deposition and wound closure through protein regulation of p53, αSMA, E-cadherin, and SOD1 are some of the mechanisms by which F_IV of P. crocatum is involved in diabetic wound healing therapy.     

Antiparasitic effects of Elettaria cardamomum L. essential oil and its main compounds, 1-8 Cineole alone and in combination with albendazole against Echinococcus granulosus protoscoleces

BackgroundThe present investigation aims to determine the chemical structure and protoscolicidal effects of Elettaria cardamomum L. essential oil (ECEO) and its main compounds 1–8 cineole alone and along with albendazole (ALZ) against Echinococcus granulosus protoscoleces in vitro and ex vivo. We also decided to evaluate some cellular mechanisms such as the apoptotic activity and the permeability of plasma membrane of protoscoleces treated with ECEO and 1–8 cineole.MethodsHydatid cyst protoscoleces were divided into seven groups including protoscoleces treated with ECEO 50 µl/mL (T1), protoscoleces treated with ECEO 100 µl/mL (T2), protoscoleces treated with ECEO 200 µl/mL (T3), protoscoleces treated with 1–8 cineole 100 µg/mL (T4), protoscoleces treated with 1–8 cineole 200 µg/mL (T5), protoscoleces treated with 1–8 cineole 100 µg/mL + albendazole 50 µg/mL (T6), and protoscoleces treated with 1–8 cineole 200 µg/mL + albendazole ALZ-50 µg/mL (T7). The viability of protoscoleces were recorded by eosin staining examination. Moreover, the induction of apoptosis and the plasma membrane permeability of the protoscoleces treated with ECEO and 1–8 cineole were evaluated.ResultsThe highest protoscolicidal effect of ECEO was observed at the dose of 200 µl/ml (T3). 1,8-Cineole alone and combined with ALZ, particularly at the dose of 200 µg/ml (T5 and T7), destroyed the 100% protoscolices after 10 min incubation. The ECEO (T1-T3) and 1–8 cineole alone (T4 and T5) and in combination with ALZ (T6 and T7) took longer to display their protoscolicidal effect ex vivo. The obtained results of relative fuorescent items exhibited that the protoscoleces incubated with ECEO and 1,8-Cineole, alter the permeability of plasma membrane by Sytox Green with increasing the concentration. The findings revealed exhibited that ECEO and 1,8-Cineole increasingly and dose-dependently induced activation of caspase-3 enzyme ranging from 6.8 to 23.3%.ConclusionOur obtained results revealed that ECEO and its main compound, 1,8-Cineole exhibited the potent protoscolicidal in vitro and ex vivo; and if more research is done on their efficacy and toxicity in animal models and even clinical setting, it can be suggested as a protoscolicidal agent to use during hydatid cyst surgery.     

Cytotoxicity of a naturally occurring furoquinoline alkaloid and four acridone alkaloids towards multi-factorial drug-resistant cancer cells

IntroductionChemotherapy is one of the preferred mode of treatment of malignancies, but is complicated by the expression of diverse resistance mechanisms of cancer cells.MethodsIn the present study, we investigated the cytotoxicity of five alkaloids including a furoquinoline montrofoline (1) and four acridones namely 1-hydroxy-4-methoxy-10-methylacridone (2), norevoxanthine (3), evoxanthine (4), 1,3-dimethoxy-10-methylacridone (5) against 9 drug-sensitive and multidrug-resistant (MDR) cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species (ROS) were all analyzed via flow cytometry.ResultsFuroquinoline 1 as well as the acridone alkaloids 2–5 displayed cytotoxic effects with IC₅₀ values below 138 µM on all the 9 tested cancer cell lines. The IC₅₀ values ranged from 41.56 µM (towards hepatocarinoma HepG2 cells) to 90.66 µM [towards colon carcinoma HCT116 (p53^−/−) cells] for 1, from 6.78 µM [towards HCT116 (p53^−/−) cells) to 106.47 µM [towards breast adenocarcinoma MDA-MB-231-pcDNA cells] for 2, from 5.72 µM (towards gliobastoma U87MG.ΔEGFR cells) to 137.62 µM (towards leukemia CCRF-CEM cells] for 3, from 6.11 µM [towards HCT116 (p53^+/+) cells] to 80.99 µM (towards HepG2 cells] for 4, from 3.38 µM (towards MDA-MB-231-BCRP cells) to 58.10 µM (towards leukemia CEM/ADR5000 cells] for 5 and from 0.20 µM (against CCRF-CEM cells) to 195.12 µM (against CEM/ADR5000 cells) for doxorubicin. Acridone alkaloid 5 induced apoptosis in CCRF-CEM leukemia cells, mediated by increased ROS production.ConclusionsThe five tested alkaloids and mostly acridone 5 are potential cytotoxic natural products that deserve more investigations to develop novel cytotoxic compounds against multifactorial drug-resistant cancers.     

The impact of PSA and digital rectal examination on the risk of prostate cancer specific mortality in men with a PSA level <2.5 ng/ml

IntroductionIt is unknown whether a normal range, diagnostic serum prostate specific antigen (PSA) level's influence on prostate cancer specific mortality (PCSM) is dependent upon digital rectal examination (DRE) findings.MethodsBetween 2004 and 2007, 9081 men diagnosed with non-palpable (T1c, N = 1710) or palpable (T2–T4, N = 7371) and non-metastatic prostate cancer (PC) were identified from surveillance, epidemiology, and end results data, selected based on pre-treatment PSA < 2.5 ng/ml. A multivariable competing risks regression model evaluated whether DRE findings interacted with PSA level in predicting risk of PCSM.ResultsAfter median follow-up of 2.83 years, 118 of 548 deaths (21.5%) were due to PC. Increasing diagnostic PSA was associated with increased risk of PCSM (AHR = 3.52; 95% CI: 1.25–9.89; P = .017) in men with T1c, Gleason score 7–10 PC, but decreased PCSM risk (AHR = 0.66; 95% CI: 0.52–0.83; P < .001) for men with T2–T4 PC and any Gleason score.DiscussionFor men with diagnostic PSA level <2.5 ng/ml and palpable PC, risk of early PCSM increases by 34% for a 1 point decrease in PSA from 2. This suggests the existence of clinically detectable, low PSA secreting disease with an elevated risk of early PCSM, highlighting the importance of the DRE in men with PC and normal range, diagnostic PSA.     

五苓胶囊对前列腺癌循环miRNA-141表达的影响

目的:采用荧光定量PCR法检测前列腺癌循环miRNA-141表达,并研究五苓胶囊对其影响。方法:选取我院泌尿外科收治的前列腺癌患者20例,随机分为A、B两组,各10例;A组给予常规治疗,B组在常规治疗基础上给予加用五苓胶囊治疗。选取同期住院前列腺增生患者20例,正常对照组为同时期体检健康者20例。采用荧光定量PCR法检测正常对照组、前列腺增生组以及前列腺癌组血清miRNA-141的表达情况,以及前列腺癌组治疗前TPSA(前列腺特异性抗原)含量。结果:前列腺癌组的血清miRNA-141的表达水平为正常对照组的(11.22±8.19)倍,明显高于前列腺增生组(1.65±1.73)和正常对照组,差异有统计学意义(P0.05);前列腺增生组和正常对照组比较无明显差异(P0.05);前列腺癌组血清miRNA-141的表达水平与TPSA水平呈正相关关系,相关系数r=0.753,有统计学意义(P0.05)。治疗后,前列腺癌A组与B组的血清miRNA-141的表达水平均有所改善,与A组(5.82±4.51)相比较,B组的miRNA-141的表达水平(1.93±0.67)明显降低,差异有统计学意义(P0.05)。结论:前列腺癌患者血清中miRNA-141表达水平明显升高,且与TPSA水平呈正相关关系,五苓胶囊能够降低miRNA-141表达。     

Results of combined radiotherapy and hormonal treatment of prostate cancer patients with initial PSA value >40 ng/ml

AimTo evaluate the outcome of prostate cancer patients with initial PSA value >40 ng/ml.BackgroundThe outcome of prostate cancer patients with very high initial PSA value is not known and patients are frequently treated with palliative intent. We analyzed the outcome of radical combined hormonal treatment and radiotherapy in prostate cancer patients with initial PSA value >40 ng/ml.MethodsBetween January 2003 and December 2007 we treated, with curative intent, 56 patients with non-metastatic prostate cancer and initial PSA value >40 ng/ml. The treatment consisted of two months of neoadjuvant hormonal treatment (LHRH analog), radical radiotherapy (68–78 Gy, conformal technique) and an optional two-year adjuvant hormonal treatment.ResultsThe median time of follow up was 61 months. 5-Year overall survival was 90%. 5-Year biochemical disease free survival was 62%. T stage, Gleason score, PSA value, and radiotherapy dose did not significantly influence the outcome. Late genitourinal and gastrointestinal toxicity was acceptable.ConclusionRadical treatment in combination with hormonal treatment and radiotherapy can be recommended for this subgroup of prostate cancer patients with good performance status and life expectancy.     

Insecticidal and acetylcholinesterase inhibitory activities of Achillea biebersteinii essential oil and its nanoemulsion and major monoterpenes against Tribolium castaneum

Essential oil (EO) was hydrodistilled from Achillea biebersteinii and analyzed using gas chromatography–flame ionization detection (GC–FID) and (GC–MS). Three monoterpenes, α-terpinene, p-cymene, and camphor were isolated as the main terpenes in the EO. Oil-in-water nanoemulsion (particle size 52.7 ± 4.4 nm) was prepared and characterized from EO through a hydrothermal approach. The EO products caused insecticidal effects and altered F₁ progeny of the red flour beetle, Tribolium castaneum (Herbst) in a dose and exposure time-dependent manner. The nanoemulsion was superior in bioactivity, followed EO. At 12.5 µl/cm², nanoemulsion and EO caused 100% mortality of the second larvae after 4 days of exposure with reduction of F₁ progeny of 100.0 and 89.2%, respectively. At 50.0 µl/cm², percentage mortality and reduction in progeny of EO products ranged between (61.4–100%) and (53.0–100%), respectively. Upon fumigation, nanoemulsion at 10 µl/L air caused 100% mortality of the second larvae after 4 days of exposure. At 20 µl/L air and 4 days after treatment, percentage mortality with the remainder botanicals ranging between 64.7 and 100. LC₅₀′s of products after 48 h exposure ranging between 6.7 and 58.1 µg/cm² in insecticidal bioassay, and between 3.6 and 26.3 µl/L upon fumigation. Botanicals caused a remarkable inhibition of acetylcholinesterase activity (AChE), where nanoemulsion (IC₅₀ = 14.22 mM), EO (IC₅₀ = 35.12 mM) and camphor (IC₅₀ = 23.93 mM) were superior as AChE inhibitors. There is a potential for using of A. biebersteinii EO, its nanoemulsion and monoterpenes as natural grain protectants after the required toxicological investigations.     

Toxic copper level increases erythrocyte glycolytic rate,glutathione production and alters electrolyte balance in male Wistar rats

BackgroundCopper is a micronutrient vital to several cellular energy metabolic processes and drives erythropoiesis. However, it disrupts cellular biological activities and causes oxidative damage when in excess of cellular needs. This study investigated the effects of copper toxicity on erythrocyte energy metabolism in male Wistar rats.MethodsTen Wistar rats (150–170 g) were randomly divided into 2 groups: control (given 0.1 ml distilled water) and copper toxic (given 100 mg/kg copper sulphate). Rats were orally treated for 30 days. Blood, collected retro-orbitally after sodium thiopentone anaesthesia (50 mg/kg i.p.) into fluoride oxalate and EDTA bottles, was subjected to blood lactate assay and extraction of red blood cell respectively. Red blood cell nitric oxide (RBC NO), glutathione (RBC GSH), adenosine triphosphate (RBC ATP) levels, RBC hexokinase, glucose-6-phosphate (RBC G6P), glucose-6-phosphate dehydrogenase (RBC G6PDH), and lactate dehydrogenase (RBC LDH) activity was estimated spectrophotometrically. Values (Mean±SEM, n = 5) were compared by Student’s unpaired T-test at p < 0.05.Results and conclusionCopper toxicity significantly increased RBC hexokinase (23.41 ± 2.80 µM), G6P (0.48 ± 0.03 µM), G6PDH (71.03 ± 4.76nmol/min/ml) activities, ATP (624.70 ± 57.36 µmol/gHb) and GSH (3.08 ± 0.37 µM) level compared to control (15.28 ± 1.37 µM, 0.35 ± 0.02 µM, 330.30 ± 49.58 µmol/gHb, 54.41 ± 3.01nmol/min/ml and 2.05 ± 0.14 µM respectively, p < 0.05). Also, RBC LDH activity (145.00 ± 19.88mU/ml), NO (3.45 ± 0.25 µM) and blood lactate (31.64 ± 0.91 mg/dl) level were lowered significantly compared to control (467.90 ± 94.23mU/ml, 4.48 ± 0.18 µM and 36.12 ± 1.06 mg/dl respectively). This study shows that copper toxicity increases erythrocyte glycolytic rate and glutathione production. This increase could be connected to a compensatory mechanism for cellular hypoxia and increased free radical generation.     

Relationship of Prostate -Specific Antigen to Age and Testosterone in Men With Type 2 Diabetes Mellitus

ObjectiveTo determine whether prostate-specific antigen (PSA) concentrations in type 2 diabetic men with hypogonadotrophic hypogonadism are lower than those in eugonadal men with type 2 diabetes and whether PSA concentrations are related to plasma testosterone concentrations.MethodsIn this cross-sectional study, we measured serum total testosterone, sex hormone–binding globulin, free testosterone, PSA, hematocrit, and hemoglobin A_1c in consecutive type 2 diabetic men who presented to 2 endocrinology referral centers between January 2006 and January 2007. We collected other clinical and demographic data including age, height, weight, and ethnicity.ResultsOf 400 eligible patients, 280 men met inclusion criteria. Plasma PSA concentrations were lower in type 2 diabetic men with low free testosterone concentrations than in those with normal free testosterone concentrations (25.65 ± 2.02 ng/dL vs 31.70 ± 2.31 ng/dL, P = .011). PSA concentrations were positively related to age (r = 0.34, P < .001), total testosterone (r = 0.29, P < .001), free testosterone (r = 0.17, P = .02), and sex hormone– binding globulin (r = 0.22, P < .001) and negatively related to body mass index (r = –0.28, P < .001). In stepwise backward regression analysis, PSA concentration was predicted by age (P < .001) and free testosterone (P < .001), but not by body mass index or sex hormone–binding globulin.ConclusionsPlasma PSA concentrations are lower in type 2 diabetic men with hypogonadism than in eugonadal men with type 2 diabetes, and plasma PSA is related to age, plasma total testosterone concentrations, and free testosterone concentrations in patients with type 2 diabetes. (Endocr Pract. 2008;14:1000-1005)     

The cajanine derivative LJ101019C regulates the proliferation and enhances the activity of NK cells via Kv1.3 channel-driven activation of the AKT/mTOR pathway

BackgroundNatural killer (NK) cells play important roles in immune responses and have been wildly used in immunotherapy. Nevertheless, some limitations remain. It is urgent to explore novel and safe strategies to enhance NK cell activity.PurposeThe aim of this study was to investigate the immuno-stimulatory effects and to reveal the molecular mechanism of LJ101019C, a derivative of a natural small-molecule compounds cajanine, on NK cells.MethodsCell proliferation was examined by CCK8 assay, then we used the cytotoxicity detection kit to detect the cytotoxicity of NK cells. The change of cell cycle, intracellular reactive oxygen species (ROS) level and mitochondrial mass were evaluated by FACS and Operetta high-content image analysis, respectively. Furthermore, the IFN-γ secretion of NK cells were measured by ELISA. The Kv1.3 protein expression and function were detected by western blot and patch-clamp technique, respectively. The role of Kv1.3 in AKT/mTOR pathway activation was determined by western blot.ResultsThe results showed that LJ101019C at relatively low concentrations (0.05–0.1 µM) significantly increased the proliferation of NK cells. And 1 µM LJ101019C could elevate the proportion of NK cells in the S-phase of the cell cycle (*p < 0.1). Furthermore, the cytotoxic effects of NK cells targeting MIA PaCa-2 cells were significantly enhanced by 0.1 and 1 µM LJ101019C, and were associated with the enhanced secretion of IFN-γ by NK cells (*p < 0.1; **p < 0.05). 0.1 and 1 µM LJ101019C increased intracellular levels of ROS (**p < 0.05), and 0.1 µM LJ101019C elevated mitochondrial mass (*p < 0.1). Electrophysiological recordings indicated that LJ101019C led to a remarkably increase the Kv1.3 current density. Moreover, western blot results indicated that LJ101019C elevated Kv1.3 protein expression and activated AKT/mTOR signaling via increasing the expression of Kv1.3 in NK cells.ConclusionLJ101019C increases the proliferation and the cytotoxicity of NK cells at relatively low concentrations. The mechanism is the activation of AKT/mTOR signaling pathway driven by up-regulation of Kv1.3 in NK cells. These suggest LJ101019C is a promising candidate for improving the efficacy of NK cell-based immunotherapies.     

Cytotoxicity of compounds from Xylopia aethiopica towards multi-factorial drug-resistant cancer cells

IntroductionMultidrug resistance (MDR) in cancer represent a major hurdle in chemotherapy. Previously, the methanol extract of the medicinal spice Xylopia aethiopica displayed considerable cytotoxicity against multidrug resistant (MDR) cancer cell lines.MethodsThe present study was designed to assess the cytotoxicity of compounds, 16α-hydroxy-ent-kauran-19-oic acid (2), 3,4′,5-trihydroxy-6″,6″-dimethylpyrano[2,3-g]flavone (3), isotetrandrine (5) and trans-tiliroside (6) derived from the methanol crude extract of Xylopia aethiopica against 9 drug-sensitive and -resistant cancer cell lines. The resazurin reduction assay was used to evaluate the cytotoxicity of these compounds, whilst caspase-Glo assay was used to detect caspase activation. Cell cycle, mitochondrial membrane potential (MMP) and levels of reactive oxygen species (ROS) were all analyzed via flow cytometry.ResultsFlavonoid 3 and alkaloid 5 also displayed IC₅₀ values ranging from 2.61 µM (towards leukemia CCRF-CEM cells) to 18.60 µM (towards gliobastoma multiforme U87MG.ΔEGFR cells) and from 1.45 µM (towards HepG2 cells) to 7.28 µM (towards MDA-MB-231-pcDNA cells), respectively. IC₅₀ values ranged from 0.20 µM (against CCRF-CEM cells) to 195.12 µM (against CEM/ADR5000 cells) for doxorubicin. Compound 3 induced apoptosis in leukemia CCRF-CEM cells mediated by the disruption of the MMP, whilst 5 induced apoptosis mediated by ROS production.ConclusionsCompounds 2 and 5 represent potential cytotoxic phytochemicals that deserve more investigations to develop novel antineoplastic drugs against multifactorial drug-resistant cancers.     

Transient blockade of TBK1/IKKε allows efficient transduction of primary human natural killer cells with vesicular stomatitis virus G-pseudotyped lentiviral vectors

Background aimsVesicular stomatitis virus G (VSV-G)-pseudotyped lentiviral vectors (LVs) are widely used to reliably generate genetically modified, clinical-grade T-cell products. However, the results of genetically modifying natural killer (NK) cells with VSV-G LVs have been variable. The authors explored whether inhibition of the IKK-related protein kinases TBK1 and IKKε, key signaling molecules of the endosomal TLR4 pathway, which is activated by VSV-G, would enable the reliable transduction of NK cells by VSV-G LVs.MethodsThe authors activated NK cells from peripheral blood mononuclear cells using standard procedures and transduced them with VSV-G LVs encoding a marker gene (yellow fluorescent protein [YFP]) or functional genes (chimeric antigen receptors [CARs], co-stimulatory molecules) in the presence of three TBK1/IKKε inhibitors (MRT67307, BX-795, amlexanox). NK cell transduction was evaluated by flow cytometry and/or western blot and the functionality of expressed CARs was evaluated in vitro.ResultsBlocking TBK1/IKKε during transduction of NK cells enabled their efficient transduction by VSV-G LVs as judged by YFPexpression of 40–50%, with half maximal effective concentrations of 1.1 µM (MRT67307), 5 µM (BX-795) and 24.8 µM (amlexanox). Focusing on MRT67307, the authors successfully generated NK cells expressing CD19-CARs or HER2-CARs with an inducible co-stimulatory molecule. CAR NK cells exhibited increased cytolytic activity and ability to produce cytokines in comparison to untreated controls, confirming CAR functionality.ConclusionsThe authors demonstrate that inhibition of TBK1/IKKε enables the reliable generation of genetically modified NK cells using VSV-G LVs. The authors’ protocol can be readily adapted to generate clinical-grade NK cells and thus has the potential to facilitate the clinical evaluation of genetically modified NK cell-based therapeutics in the future.     

Monte Carlo study of the influence of energy spectra,mesh size,high Z element on dose and PVDR based on 1-D and 3-D heterogeneous mouse head phantom for Microbeam Radiation Therapy

PurposeTo evaluate the influence of energy spectra, mesh sizes, high Z element on dose and PVDR in Microbeam Radiation Therapy (MRT) based on 1-D analogy-mouse-head-model (1-D MHM) and 3-D voxel-mouse-head-phantom (3-D VMHP) by Monte Carlo simulation.MethodsA Microbeam-Array-Source-Model was implemented into EGSnrc/DOSXYZnrc. The microbeam size is assumed to be 25 μm, 50 μm or 75 μm in thickness and fixed 1 mm in height with 200 μm c-t-c. The influence of the energy spectra of ID17@ESRF and BMIT@CLS were investigated. The mesh size was optimized. PVDR in 1-D MHM and 3-D VMHP was compared with the homogeneous water phantom. The arc influence of 3-D VMHP filled with water (3-D VMHWP) was compared with the rectangle phantom.ResultsPVDR of the lower BMIT@CLS spectrum is 2.4 times that of ID17@ESRF for lower valley dose. The optimized mesh is 5 µm for 25 µm, and 10 µm for 50 µm and 75 µm microbeams with 200 µm c-t-c. A 500 μm skull layer could make PVDR difference up to 62.5% for 1-D MHM. However this influence is limited (<5%) for the farther homogeneous media (e.g. 600 µm). The peak dose uniformity of 3-D VMHP at the same depth could be up to 8% for 1.85 mm × 1 mm irradiation field, whereas that of 3-D VMHWP is <1%. The high Z element makes the dose uniformity enhance in target. The surface arc could affect the superficial PVDR (from 44% to 21% in 0.2 mm depth), whereas this influence is limited for the more depth (<1%).ConclusionAn accurate MRT dose calculation algorithm should include the influence of 3-D heterogeneous media.     

Synthesis of substituted biphenyl methylene indolinones as apoptosis inducers and tubulin polymerization inhibitors

A new series of biphenyl methylene indolinones has been designed, synthesized and evaluated for their in vitro antiproliferative activity against various cancer cell lines like DU-145 (prostate cancer cell line), 4T1 (mouse breast cancer cell line), MDA-MB-231 (human breast cancer cell line), BT-549 (human breast cancer cell line), T24 (human urinary bladder carcinoma cell line), and HeLa (cervical cancer cell line). Among the series, compound 10e showed potent in vitro cytotoxic activity against HeLa and DU-145 cancer cell lines with IC₅₀ value of 1.74 ± 0.69 µM and 1.68 ± 1.06 µM respectively. To understand the underlying mechanism of most potent cytotoxic compound 10e, various mechanistic studies were carried out on DU-145 cell lines. Cell cycle analysis results revealed that these conjugates affect both G0/G1 and G2/M phase of the cycle, tubulin binding assay resulted that compound 10e interrupting microtubule network formation by inhibiting tubulin polymerization with IC₅₀ value of 4.96 ± 0.05 μM. Moreover, molecular docking of 10e on colchicine binding site of the tubulin explains the interaction of 10e with tubulin. Clonogenic assay indicated inhibition of colony formation by compound 10e in a dose dependent manner. In addition, morphological changes were clearly observed by AO/EB and DAPI staining studies. Moreover, ROS detection using DCFDA, JC-1, and annexin V-FITC assays demonstrated the significant apoptosis induction by 10e.     

Antileishmanial activity and trypanothione reductase effects of terpenes from the Amazonian species Croton cajucara Benth (Euphorbiaceae)

BackgroundLeishmaniasis comprises several infectious diseases caused by protozoa parasites of Leishmania genus. In recent years, there has been a growing interest in the therapeutic use of natural products to treat parasitic diseases. Among them Croton cajucara Benth. (Euphorbiaceae) is a plant found in the Amazonian region with a history of safe use in folk medicine.PurposeThe purpose of this study was to investigate the effects of clerodane diterpenes, trans-dehydrocrotonin (DCTN), trans-crotonin (CTN) and acetylaleuritolic acid (AAA) obtained from powdered bark of C. cajucara against promastigotes, axenic and intracellular amastigotes of Leishmania amazonensis. Furthermore, the effects of DCTN and CTN on the trypanotiona reductase enzyme were also investigated. The extraction of the terpenes was carried out as previously reported (Maciel et al., 1998, Maciel et al., 2003).MethodsThe effect of the isolated compounds (DCTN, CTN and AAA) from the bark of C. cajucara was assessed in vitro against promastigotes, axenic amastigotes and intracellular amastigotes of L. amazonensis by counting of remaining parasites in a Neubauer chamber in comparison to pentamidine used as standard drug. The action of natural products on trypanothione reductase was assessed using soluble protein fraction of promastigotes. The assays were performed by incubation with HEPES, EDTA, NADPH and trypanothione disulfide to quantify the NAPH consumption by TryR.ResultsThe results showed very high efficacy, especially of the diterpene DCTN, against promastigotes (IC₅₀ = 6.30 ± 0.06 µg/ml) and axenic amastigotes (IC₅₀ = 19.98 ± 0.05 µg/ml) of L. amazonenesis. The cytotoxic effect of the best active natural product was evaluated on mouse peritoneal infected macrophages (IC₅₀ = 0.47 ± 0.03 µg/ml in 24 h of culture), and the treatment revealed that DCTN never reaches toxic concentrations while reducing the infection and, most importantly, with no toxicity (>100 µg/ml with 0% of macrophage kill) when compared to pentamidine (37.5 µg/ml with 100% of macrophage kill). Furthermore, all of the natural products assayed on the trypanothione reductase enzyme inhibited the enzyme activity compared to the control.ConclusionClerodane diterpenes from C. cajucara showed promising in vitro antileishmanial effects against L. amazonensis, specially the DCTN with no macrophage toxicity up to the assayed concentration. In addition, the action on trypanothione reductase enzyme revealed a possible mechanism of action.     

Detection of pyrrolizidine alkaloids in German licensed herbal medicinal teas

BackgroundBecause of the hepatotoxic, mutagenic, and cancerogenic effects of pyrrolizidine alkaloids (PAs) the German Federal Institute for Risk Assessment (BfR) recommends not to exceed a daily PA intake of 0.007 µg/kg body weight (0.42 µg/60 kg adult). In a recent study conducted by the BfR, up to 5647 µg PA/kg dried herbal material were detected in tea products marketed as food.PurposeThe present study aimed at elucidating whether medicinal teas licensed or registered as medicinal products contain PAs as well.Study designOne hundred sixty-nine different commercially available medicinal teas, i.e. 19 nettle (Urtica dioica L.), 12 fennel (Foeniculum vulgare Mill.), 14 chamomile (Matricaria recutita L.), 11 melissa (Melissa officinalis L.) and 4 peppermint (Mentha piperita L.) teas as well as 109 tea mixtures were analyzed for the presence of 23 commercially available PAs.MethodLC/MS was used for the determination of the PAsResultsIn general, the total PA contents ranging 0–5668 µg/kg. Thirty percent of the tested single-ingredient tea products and 56.9% of the tested medicinal tea mixtures were found to contain PA concentrations above the limit of quantification (LOQ) of 10 µg/kg. In 11 medicinal teas PA contents >300 µg/kg dry herb were determined thus exceeding the recommended limit for PA intake by BfR. In addition three products of the investigated tea mixtures revealed extremely high PA contents of 4227, 5137, and 5668 µg/kg. Generally, single-ingredient tea products contained much less or even no detectable amounts of PAs when compared to the tea mixtures. PAs in the range between 13 and 1080 µg/kg were also detected in five analyzed aqueous herbal infusions of the medicinal tea mixture products with the highest PA content. Two out of the five investigated herbal infusions exceeded the recommended BfR limit for PA intake.ConclusionThis study demonstrates clearly that also medicinal teas licensed as medicinal products may partly contain high amounts of PAs exceeding current recommendations. For that reason manufacturers are advised to carry out more rigorous quality control tests devoted to the detection of PAs. This is very important to minimize PAs in medicinal teas accounting for possible additional exposure of the consumer to PAs from other food sources (e.g. honey).     

Medicarpin and millepurpan,two flavonoids isolated from Medicago sativa,induce apoptosis and overcome multidrug resistance in leukemia P388 cells

BackgroundHigh consumption of flavonoids has been associated with a decrease risk of cancer. Alfalfa (Medicago sativa) leaves have been widely used in traditional medicine and is currently used as a dietary supplement because of their high nutrient content. We previously reported the cytotoxic activity of alfalfa leaf extracts against several sensitive and multidrug resistant tumor cell lines.Hypothesis/purposeWe aimed to determine whether medicarpin and millepurpan, two isoflavonoids isolated from alfalfa leaves, may have pro-apoptotic effects against drug-sensitive (P388) and multidrug resistant P388 leukemia cells (P388/DOX).Study design/methodsCells were incubated with medicarpin or millepurpan for the appropriate time. Cell viability was assessed by the MTT assay. DNA fragmentation was analyzed by agarose gel electrophoresis. Cell cycle analysis was realized by flow cytometry technics. Caspases 3 and 9 activities were measured using Promega caspACE assay kits. Proteins and genes expression were visualized respectively by western-blot using specific antibodies and RT-PCR assay.ResultsP-glycoprotein-expressing P388/DOX cells did not show resistance to medicarpin (IC₅₀ ≈ 90 µM for P388 and P388/DOX cells) and millepurpan (IC₅₀ = 54 µM and 69 µM for P388 and P388/DOX cells, respectively). Treatment with medicarpin or millepurpan triggered apoptosis in sensitive as well as multidrug resistant P388 cells. These effects were mediated through the mitochondrial pathway by modifying the balance pro/anti-apoptotic proteins. While 3 µM doxorubicin alone could not induce cell death in P388/DOX cells, concomitant treatment with doxorubicin and subtoxic concentration of medicarpin or millepurpan restored the pro-apoptotic cascade. Each compound increased sensitivity of P388/DOX cells to doxorubicin whereas they had no effect in sensitive P388 cells. Vinblastine cytotoxicity was also enhanced in P388/DOX cells (IC₅₀ = 210 nM to 23 and 25 nM with medicarpin and millepurpan, respectively). This improved sensitivity was mediated by an increased uptake of doxorubicin in P388/DOX cells expressing P-gp. P-gp expression was not altered by exposure to medicarpin and millepurpan.ConclusionThese data indicate that medicarpin and millepurpan possess pro-apoptotic properties and potentiate the cytotoxicity of chemotherapy drugs in multidrug resistant P388 leukemia cells by modulating P-gp-mediated efflux of drugs. These flavonoids may be used as chemopreventive agents or as sensitizer to enhance cytotoxicity of chemotherapy drugs in multidrug resistant cancer cells.