A novel nanoformulation of parthenolide coated with polydopamine shows selective cytotoxicity and induces apoptosis in gastric cancer cells.

An anticancer agent derived from a natural product, parthenolide (PN), was studied to formulate PN into poly(lactic-co-glycolic acid) (PLGA). Polydopamine (PDA) was employed to modify the surface of PN-PLGA. Following characterization, the PN-PLGA-PDA was evaluated for its in vitro release, cytotoxicity, and ability to induce apoptosis using flow cytometry and real-time quantitative PCR. According to the present study, PN-PLGA-PDA had a size of 195.5 nm which is acceptable for efficient enhanced permeation and retention (EPR) performance. The SEM results confirmed the size and spherical shape of the nanoparticles. The percentage of encapsulation efficiency was 96.9%. The zeta potential of PN-PLGA-PDA was - 31.8 mV which was suitable for its stability. FTIR spectra of the PN-PLGA-PDA indicated the chemical stability of the PN due to intermolecular hydrogen bonds between polymer and drug. The release of PN from PN-PLGA-PDA in PBS (pH 7.4) was only 20% during the first 48 h and less than 40% during 144 h. PN-PLGA-PDA exhibited anticancer properties in a dose-dependent manner that was more cytotoxic against cancer cells than normal cells. Moreover, real-time qPCR results indicated that the formulation activated apoptosis genes to exert its cytotoxic effect and activate the NF-kB pathway. Based on our findings, PN-PLGA-PDA could serve as a potential treatment for cancer.

Inhibition of Autophagy Promotes Hemistepsin A-Induced Apoptosis via Reactive Oxygen Species-Mediated AMPK-Dependent Signaling in Human Prostate Cancer Cells.

Chemotherapy is an essential strategy for cancer treatment. On the other hand, consistent exposure to chemotherapeutic drugs induces chemo-resistance in cancer cells through a variety of mechanisms. Therefore, it is important to develop a new drug inhibiting chemo-resistance. Although hemistepsin A (HsA) is known to have anti-tumor effects, the molecular mechanisms of HsA-mediated cell death are unclear. Accordingly, this study examined whether HsA could induce apoptosis in aggressive prostate cancer cells, along with its underlying mechanism. Using HsA on two prostate cancer cell lines, PC-3 and LNCaP cells, the cell analysis and in vivo xenograft model were assayed. In this study, HsA induced apoptosis and autophagy in PC-3 cells. HsA-mediated ROS production attenuated HsA-induced apoptosis and autophagy after treatment with N-acetyl-L-cysteine (NAC), a ROS scavenger. Moreover, autophagy inhibition by 3-MA or CQ is involved in accelerating the apoptosis induced by HsA. Furthermore, we showed the anti-tumor effects of HsA in mice, as assessed by the reduced growth of the xenografted tumors. In conclusion, HsA induced apoptosis and ROS generation, which were blocked by protective autophagy signaling.

Patchouli alcohol ameliorates skeletal muscle insulin resistance and NAFLD via AMPK/SIRT1-mediated suppression of inflammation.

Obesity-induced chronic low-grade inflammation and thus causes various metabolic diseases, such as insulin resistance and non-alcoholic fatty liver disease (NAFLD). Patchouli alcohol (PA), an active component extracted from patchouli, displayed anti-inflammatory effects on different cell types. However, the impact of PA on skeletal muscle insulin signaling and hepatic lipid metabolism remains unclear. This study aimed to investigate whether PA would affect insulin signaling impairment in myocytes and lipid metabolism in hepatocytes. Treatment with PA ameliorated palmitate-induced inflammation and aggravation of insulin signaling in C2C12 myocytes and lipid accumulation in HepG2 hepatocytes. Treatment of C2C12 myocytes and HepG2 cells with PA augmented AMP-activated protein kinase (AMPK) phosphorylation and Sirtuin 1 (SIRT1) expression in a dose-dependent manner. siRNA-mediated suppression of AMPK or SIRT1 mitigated the effects of PA on palmitate-induced inflammation and insulin resistance in C2C12 myocytes and lipid accumulation in HepG2 cells. Animal experiments demonstrated that PA administration increased AMPK phosphorylation and SIRT1 expression, and ameliorated inflammation, thereby attenuating skeletal muscle insulin resistance and hepatic steatosis in high-fat diet-fed mice. These results denote that PA alleviates skeletal muscle insulin resistance and hepatic steatosis through AMPK/SIRT1-dependent signaling. This study might provide a novel therapeutic approach for treating obesity-related insulin resistance and NAFLD.

Dietary supplementation with nerolidol improves the antioxidant capacity and muscle fatty acid profile of Brycon amazonicus exposed to acute heat stress.

An increase in water temperature in the Amazon River has elicited concerns about commercially important fish species associated with food security, such as matrinxã (Brycon amazonicus). Studies have demonstrated the positive effects of diets supplemented with plant-based products that combat heat stress-induced oxidative damage. The aim of this study was to determine whether dietary supplementation with nerolidol prevents or reduces muscle oxidative damage and impairment of the fillet fatty acid profile of matrinxã exposed to heat stress. Plasma and muscle reactive oxygen species (ROS) and lipid peroxidation (LPO) levels were significantly higher in fish exposed to heat stress compared to fish not exposed to heat stress, while plasma superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity was significantly lower. The total content of saturated fatty acids (SFA) in fillets was significantly higher in fish exposed to heat stress compared to fish not exposed to heat stress, while he total content of polyunsaturated fatty acids (PUFA) was significantly lower. Nerolidol prevented the increase of muscle LPO and plasma ROS and LPO levels in fish exposed to heat stress, and partially prevented the increase in muscle ROS levels. Diets containing nerolidol prevented the inhibition of muscle GPx activity in fish exposed to heat stress, and partially prevented the decrease of plasma GPx activity. The nerolidol-supplemented diet prevented the increase of fillet SFA in fish exposed to heat stress, while partially preventing the decrease of PUFA. We conclude that acute heat stress at 34 °C for 72 h causes plasma and muscular oxidative damage, and that homeoviscous adaptation to maintain membrane fluidity can represent a negative impact for fish consumers. A nerolidol diet can be considered a strategy to prevent heat stress-induced oxidative damage and impairment of muscle fatty acid profiles.

Cytotoxic furanosesquiterpenoids and steroids from Ircinia mutans sponges.

CONTEXT: Ircinia mutans Wilson (Irciniidae) is a sponge with antimicrobial and cytotoxic constituents. OBJECTIVE: Our objective was to characterise the cytotoxic constituents of two seasonal collections of I. mutans. MATERIALS AND METHODS: The sponges were extracted in methanol-dichloromethane and their constituents were purified and characterised using column chromatography, GC-MS, 1 D and 2 D NMR. Anti-proliferative activities of the compounds, were evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) colorimetric assay (0.25-100 µg/mL, 72 h) against leukaemia (MOLT-4), breast (MCF-7) and colon cancer (HT-29) human cells. RESULTS: Three furanosesquiterpoids; furodysin (1), ent-furodysinin (2) and furoircin (3) and ten sterols were characterised in I. mutans, for the first time. Cholesterol (4), cholesta-5, 7-dien-3ß-ol (5) and ergosterol (6) were determined in the sponge from the winter collections, while cholesta-5, 22-dien-3ß-ol (7), 24-methyldesmosterol (8), campesterol (9), stigmasterol (10), γ-ergostenol (11), chondrillasterol (12) and γ-sitosterol (13) were detected in the summer samples. The steroids from the winter collection exhibited cytotoxic activity with IC50 values of 13.0 ± 0.9, 11.1 ± 1.7 and 1.1 ± 0.4 µg/mL, against the mentioned cancer cell lines, respectively, while those from the summer sample, showed greater activity, IC50 = 1.1 ± 0.2 µg/mL against MOLT-4. The purified steroids showed potent MOLT-4 cytotoxic activity, IC50 values = 2.3-7.8 µg/mL. DISCUSSION AND CONCLUSION: The present study suggests that I. mutans is a rich source of cytotoxic steroids, and introduces 3 as new natural product. Considering the high cytotoxic activity of the steroids, these structures could be candidates for anticancer drug development in future research.

NF-κB Blockade with Oral Administration of Dimethylaminoparthenolide (DMAPT), Delays Prostate Cancer Resistance to Androgen Receptor (AR) Inhibition and Inhibits AR Variants.

NF-κB activation has been linked to prostate cancer progression and is commonly observed in castrate-resistant disease. It has been suggested that NF-κB-driven resistance to androgen-deprivation therapy (ADT) in prostate cancer cells may be mediated by aberrant androgen receptor (AR) activation and AR splice variant production. Preventing resistance to ADT may therefore be achieved by using NF-κB inhibitors. However, low oral bioavailability and high toxicity of NF-κB inhibitors is a major challenge for clinical translation. Dimethylaminoparthenolide (DMAPT) is an oral NF-κB inhibitor in clinical development and has already shown favorable pharmacokinetic and pharmacodyanamic data in patients with heme malignancies, including decrease of NF-κB in circulating leuchemic blasts. Here, we report that activation of NF-κB/p65 by castration in mouse and human prostate cancer models resulted in a significant increase in AR variant-7 (AR-V7) expression and modest upregulation of AR. In vivo castration of VCaP-CR tumors resulted in significant upregulation of phosphorylated-p65 and AR-V7, which was attenuated by combination with DMAPT and DMAPT increased the efficacy of AR inhibition. We further demonstrate that the effects of DMAPT-sensitizing prostate cancer cells to castration were dependent on the ability of DMAPT to inhibit phosphorylated-p65 function. IMPLICATIONS: Our study shows that DMAPT, an oral NF-κB inhibitor in clinical development, inhibits phosphorylated-p65 upregulation of AR-V7 and delays prostate cancer castration resistance. This provides rationale for the development of DMAPT as a novel therapeutic strategy to increase durable response in patients receiving AR-targeted therapy.

DMAPT­D6 induces death­receptor­mediated apoptosis to inhibit glioblastoma cell oncogenesis via induction of DNA damage through accumulation of intracellular ROS.

Glioblastoma (GBM) is an aggressive malignancy with a high rate of tumor recurrence after treatment with conventional therapies. Parthenolide (PTL), a sesquiterpene lactone extracted from the herb Tanacetum parthenium or feverfew, possesses anticancer properties against a wide variety of solid tumors. In the present study, a series of PTL derivatives were synthesized and screened. An inhibitor, dimethylaminoparthenolide (DMAPT)­D6, a derivative of the PTL prodrug DMAPT in which the hydrogen of the dimethylamino group is substituted for the isotope deuterium, induced significant cytotoxicity in GBM cells in vitro and induced cell cycle arrest at the S­phase in a dose­dependent manner. Furthermore, mechanistic investigation indicated that through increasing the levels of intracellular accumulation of reactive oxygen species (ROS), DMAPT­D6 triggered DNA damage and finally death receptor­mediated extrinsic apoptosis in GBM cells, suggesting that DNA damage induced by DMAPT­D6 initiated caspase­dependent apoptosis to remove damaged GBM cells. Taken together, these data suggested that ROS accumulation following treatment with DMAPT­D6 results in DNA damage, and thus, death­receptor­mediated apoptosis, highlighting the potential of DMAPT­D6 as a novel therapeutic agent for the treatment of GBM.

Cytotoxicity and molecular docking analysis of racemolactone I, a new sesquiterpene lactone isolated from Inula racemosa.

CONTEXT: Traditionally, Inula racemosa Hook. f. (Asteraceae) has been reported to be effective in cancer treatment which motivated the authors to explore the plant for novel anticancer compounds. OBJECTIVE: To isolate and characterize new cytotoxic phytoconstituents from I. racemosa roots. MATERIALS AND METHODS: The column chromatography of I. racemosa ethyl acetate extract furnished a novel sesquiterpene lactone whose structure was established by NMR (1D/2D), ES-MS and its cytotoxic properties were assessed on HeLa, MDAMB-231, and A549 cell lines using MTT and LDH (lactate dehydrogenase) assays. Further, morphological changes were analyzed by flow cytometry, mitochondrial membrane potential, AO-EtBr dual staining, and comet assay. Molecular docking and simulation were performed using Glide and Desmond softwares, respectively, to validate the mechanism of action. RESULTS: The isolated compound was identified as racemolactone I (compound 1). Amongst the cell lines tested, considerable changes were observed in HeLa cells. Compound 1 (IC50 = 0.9 µg/mL) significantly decreased cell viability (82%) concomitantly with high LDH release (76%) at 15 µg/mL. Diverse morphological alterations along with significant increase (9.23%) in apoptotic cells and decrease in viable cells were observed. AO-EtBr dual staining also confirmed the presence of 20% apoptotic cells. A gradual decrease in mitochondrial membrane potential was observed. HeLa cells showed significantly increased comet tail length (48.4 µm), indicating broken DNA strands. In silico studies exhibited that compound 1 binds to the active site of Polo-like kinase-1 and forms a stable complex. CONCLUSIONS: Racemolactone I was identified as potential anticancer agent, which can further be confirmed by in vivo investigations.

In vitro neuroprotective effects of farnesene sesquiterpene on alzheimer's disease model of differentiated neuroblastoma cell line.

OBJECTIVE: To investigate neuroprotective properties of the farnesene sesquiterpene on the experimental Alzheimer's disease model in vitro. METHODS: Human neuroblastoma cell line (SHSY-5Y) was differentiated into neuron-like cells by using retinoic acid to constitute the in vitro Alzheimer's Disease model. ß-amyloid 1-42 protein was applied to the transformed cells for 24 and 48 hours in a wide dose ranges (3.125-200 µM) to establish AD cytotoxicity. Then, farnesene was applied to cell cultures in a wide spectrum dose interval (1.625-100 µg/ml) to investigate neuroprotective effect against ß-amyloid for 24 and 48 hours. 3-(4,5-dimethyl-thiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH) release tests were executed to determine cytotoxicity in the Alzheimer model. Nuclear DNA integrity of cells was examined under the fluorescent microscope using the Hoechst 33258 staining method. Furthermore, acetylcholinesterase (AChE) activity, total antioxidant capacity (TAC) and total oxidative status (TOS) levels were analyzed to understand the protection mechanism of the farnesene application on the cell culture model. Finally, flow cytometry analysis was used to find out the cell death mechanism after beta-amyloid and farnesene application to the cell culture. RESULTS: Cell viability tests revealed significant neuroprotection against ß-amyloid toxicity in both 24 and 48 hours and the Hoechst 33258 fluorescence staining method showed a significant decrease in necrotic deaths after farnesene application in the cell cultures. Finally, flow cytometry analysis put forth that farnesene could decrease necrotic cell death up to 3-fold resulted from beta-amyloid exposure. CONCLUSION: According to the investigations, farnesene can potentially be a safe, anti-necrotic and neuroprotective agents against Alzheimer's disease.

In vitro and in vivo evaluation of cnicin from blessed thistle (Centaurea benedicta) and its inclusion complexes with cyclodextrins against Schistosoma mansoni.

Schistosomiasis, caused by a blood fluke of the genus Schistosoma, afflicts over 230 million people worldwide. Treatment of the disease relies on just one drug, praziquantel. Cnicin (Cn) is the sesquiterpene lactone found in blessed thistle (Centaurea benedicta) that showed antiparasitic activities but has not been evaluated against Schistosoma. However, cnicin has poor water solubility, which may limit its antiparasitic activities. To overcome these restrictions, inclusion complexes with cyclodextrins may be used. In this work, we evaluated the in vitro and in vivo antischistosomal activities of cnicin and its complexes with ß-cyclodextrin (ßCD) and 2-hydroxypropyl-ß-cyclodextrin (HPßCD) against Schistosoma mansoni. Cnicin were isolated from C. benedicta by chromatographic fractionation. Complexes formed by cnicin and ßCD (Cn/ßCD), as well as by cnicin and HPßCD (Cn/HPßCD), were prepared by coprecipitation and characterized. In vitro schistosomicidal assays were used to evaluate the effects of cnicin and its complexes on adult schistosomes, while the in vivo antischistosomal assays were evaluated by oral and intraperitoneal routes. Results showed that cnicin caused mortality and tegumental alterations in adult schistosomes in vitro, also showing in vivo efficacy after intraperitoneal administration. The oral treatment with cnicin or Cn/ßCD showed no significant worm reductions in a mouse model of schistosomiasis. In contrast, Cn/HPßCD complex, when orally or intraperitoneally administered to S. mansoni-infected mice, decreased the total worm load, and markedly reduced the number of eggs, showing high in vivo antischistosomal effectiveness. Permeability studies, using Nile red, indicated that HPßCD complex may reach the tegument of adult schistosomes in vivo. These results demonstrated the antischistosomal potential of cnicin in preparations with HPßCD.

The mechanism of m6A methyltransferase METTL3-mediated autophagy in reversing gefitinib resistance in NSCLC cells by ß-elemene.

N6-methyladenosine (m6A) modification can alter gene expression by regulating RNA splicing, stability, translocation, and translation. Emerging evidence shows that m6A modification plays an important role in cancer development and progression, including cell proliferation, migration and invasion, cell apoptosis, autophagy, and drug resistance. Until now, the role of m6A modification mediated autophagy in cancer drug resistance is still unclear. In this study, we found that m6A methyltransferase METTL3-mediated autophagy played an important role in reversing gefitinib resistance by ß-elemene in non-small cell lung cancer (NSCLC) cells. Mechanistically, in vitro and in vivo studies indicated that ß-elemene could reverse gefitinib resistance in NSCLC cells by inhibiting cell autophagy process in a manner of chloroquine. ß-elemene inhibited the autophagy flux by preventing autophagic lysosome acidification, resulting in increasing expression of SQSTM1 and LC3B-II. Moreover, both ß-elemene and gefitinib decreased the level of m6A methylation of gefitinib resistance cells. METTL3 was higher expressed in lung adenocarcinoma tissues than that of paired normal tissues, and was involved in the gefitinib resistance of NSCLC cells. Furthermore, METTL3 positively regulated autophagy by increasing the critical genes of autophagy pathway such as ATG5 and ATG7. In conclusion, our study unveiled the mechanism of METTL3-mediated autophagy in reversing gefitinib resistance of NSCLC cells by ß-elemene, which shed light on providing potential molecular-therapy target and clinical-treatment method in NSCLC patients with gefitinib resistance.

Anticancer and apoptotic activities of parthenolide in combination with epirubicin in mda-mb-468 breast cancer cells.

Breast cancer is the most common malignancy in women worldwide. Unfortunately, current therapeutic methods are not completely efficient. Hence, combination therapy with medicinal plants has attracted several kinds of research. In the current study, we aimed to investigate the apoptotic and anti-cancer effect of Parthenolide in combination with Epirubicin in the MDA-MB-468 breast cancer cell line. In this study,  the anti-proliferative and pro-apoptotic effect of Parthenolide in combination with Epirubicin and without it, in the MDA-MB-468 cell line have been assessed by MTT test, Hoescht staining and flow cytometry methods. Our outcomes showed that Parthenolide treatment in the present of Epirubicin led to a decrease in the minimum toxic concentration of Parthenolide and Epirubicin in comparison with individual treatments. Then, to achieve a likely molecular mechanism of mentioned drugs Bax and Bcl2 expression level evaluated by Real-time PCR and subsequently, Western blotting has been estimated the protein level of Caspase 3. Our data indicated that the treatment of cells with Parthenolide led to up-regulation of Bax and downregulation of Bcl2 at mRNA level. Moreover, Parthenolide treatment led to the obvious alternation of Caspase3 protein level. These results indicated that Parthenolide in combination with Epirubicin have significant cytotoxicity due to targeting the main regulators of apoptosis. Hence, according to lack of cytotoxicity of Parthenolide on normal cells that lead to reduction of drug side effects, it could be suggested as an adjuvant therapy with Epirubicin after complementary research on animal model and clinical trial.

Slow-binding inhibitors of acetylcholinesterase of medical interest.

Certain ligands slowly bind to acetylcholinesterase. As a result, there is a slow establishment of enzyme-inhibitor equilibrium characterized by a slow onset of inhibition prior reaching steady state. Three mechanisms account for slow-binding inhibition: a) slow binding rate constant kon, b) slow ligand induced-fit following a fast binding step, c) slow conformational selection of an enzyme form. The slow equilibrium may be followed by a chemical step. This later that can be irreversible has been observed with certain alkylating agents and substrate transition state analogs. Slow-binding inhibitors present long residence times on target. This results in prolonged pharmacological or toxicological action. Through several well-known molecules (e.g. huperzine) and new examples (tocopherol, trifluoroacetophenone and a 6-methyluracil alkylammonium derivative), we show that slow-binding inhibitors of acetylcholinesterase are promising drugs for treatment of neurological diseases such as Alzheimer disease and myasthenia gravis. Moreover, they may be of interest for neuroprotection (prophylaxis) against organophosphorus poisoning. This article is part of the special issue entitled 'Acetylcholinesterase Inhibitors: From Bench to Bedside to Battlefield'.

Nerolidol Mitigates Colonic Inflammation: An Experimental Study Using both In Vivo and In Vitro Models.

Nerolidol (NED) is a naturally occurring sesquiterpene alcohol present in various plants with potent anti-inflammatory effects. In the current study, we investigated NED as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were administered 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. Six groups received either vehicle alone or DSS alone or DSS with oral NED (50, 100, and 150 mg/kg body weight/day by oral gavage) or DSS with sulfasalazine. Disease activity index (DAI), colonic histology, and biochemical parameters were measured. TNF-α-treated HT-29 cells were used as in vitro model of colonic inflammation to study NED (25 µM and 50 µM). NED significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue Myeloperoxidase (MPO) concentrations, neutrophil and macrophage mRNA expression (CXCL2 and CCL2), and proinflammatory cytokine content (IL-1ß, IL-6, and TNF-α) both at the protein and mRNA level were significantly reduced by NED. The increase in content of the proinflammatory enzymes, COX-2 and iNOS induced by DSS were also significantly inhibited by NED along with tissue nitrate levels. NED promoted Nrf2 nuclear translocation dose dependently. NED significantly increased antioxidant enzymes activity (Superoxide dismutase (SOD) and Catalase (CAT)), Hemeoxygenase-1 (HO-1), and SOD3 mRNA levels. NED treatment in TNF-α-challenged HT-29 cells significantly decreased proinflammatory chemokines (CXCL1, IL-8, CCL2) and COX-2 mRNA levels. NED supplementation attenuates colon inflammation through its potent antioxidant and anti-inflammatory activity both in in vivo and in vitro models of colonic inflammation.

Treatment with ß-elemene combined with paclitaxel inhibits growth, migration, and invasion and induces apoptosis of ovarian cancer cells by activation of STAT-NF-κB pathway.

In this study, we aimed to analyze the anti-cancer effects of ß-elemene combined with paclitaxel for ovarian cancer. RT-qPCR, MTT assay, western blot, flow cytometry, and immunohistochemistry were used to analyze in vitro and in vivo anti-cancer effects of combined treatment of ß-elemene and paclitaxel. The in vitro results showed that ß-elemene+paclitaxel treatment markedly inhibited ovarian cancer cell growth, migration, and invasion compared to either paclitaxel or ß-elemene treatment alone. Results demonstrated that ß-elemene+paclitaxel induced apoptosis of SKOV3 cells, down-regulated anti-apoptotic Bcl-2 and Bcl-xl gene expression and up-regulated pro-apoptotic P53 and Apaf1 gene expression in SKOV3 cells. Administration of ß-elemene+paclitaxel arrested SKOV3 cell cycle at S phase and down-regulated CDK1, cyclin-B1, and P27 gene expression and apoptotic-related resistant gene expression of MDR1, LRP, and TS in SKOV3 cells. In vivo experiments showed that treatment with ß-elemene+paclitaxel significantly inhibited ovarian tumor growth and prolonged the overall survival of SKOV3-bearing mice. In addition, the treatment inhibited phosphorylated STAT3 and NF-κB expression in vitro and in vivo. Furthermore, it inhibited migration and invasion through down-regulation of the STAT-NF-κB signaling pathway in SKOV3 cells. In conclusion, the data suggested that ß-elemene+paclitaxel can inhibit ovarian cancer growth via down-regulation of the STAT3-NF-κB signaling pathway, which may be a potential therapeutic strategy for ovarian cancer therapy.

Nano magnetic liposomes-encapsulated parthenolide and glucose oxidase for ultra-efficient synergistic antitumor therapy.

Multifunctional nanoplatforms yield extremely high synergistic therapeutic effects on the basis of low biological toxicity. Based on the unique tumor microenvironment (TME), a liposomes (Lips)-based multifunctional antitumor drug delivery system known as GOD-PTL-Lips@MNPs was synthesized for chemotherapy, chemodynamic therapy (CDT), starvation therapy, and magnetic targeting synergistic therapy. Evidence has suggested that parthenolide (PTL) can induce apoptosis and consume excessive glutathione (GSH), thereby increasing the efficacy of chemodynamic therapy. On the other hand, glucose oxidase (GOD) can consume intratumoral glucose, lower pH and increase the level of H2O2 in the tumor tissue. Integrated Fe3O4 magnetic nanoparticles (MNPs) containing Fe2+ and Fe3+ effectively catalyzes H2O2 to a highly toxic hydroxyl radical (•OH) and provide magnetic targeting. During the course of in vitro and in vivo experiments, GOD-PTL-Lips@MNPs demonstrated remarkable synergistic antitumor efficacy. In particular, in mice receiving a 14 day treatment of GOD-PTL-Lips@MNPs, tumor growth was significantly inhibited, as compared with the control group. Moreover, toxicology study and histological examination demonstrated low biotoxicity of this novel therapeutic approach. In summary, our data suggests great antitumor potential for GOD-PTL-Lips@MNPs which could provide an alternative means of further improving the efficacy of anticancer therapies.

TLR2/4 promotes PGE2 production to increase tissue damage in Escherichia coli-infected bovine endometrial explants via MyD88/p38 MAPK pathway.

Prostaglandin E2 (PGE2), a lipid mediator, is released by several cell types including endometrial cells and plays a central role in bacterial infection of the endometrium during inflammation. PGE2 production accumulated in Escherichia coli (E. coli) -infected bovine endometrial tissue, which increased E. coli-infected endometrial tissue damage. However, the mechanisms of PGE2 accumulation in the E. coli-infected endometrium during inflammation-associated endometrial tissue damage remain unclear. This study was conducted to investigate the role of Toll-like receptors (TLRs) 2 and 4 in increased PGE2 production in E. coli-infected endometrial tissue. E. coli and TLR2/4 agonists significantly induced cyclooxygenase-2 and microsomal prostaglandin E synthase-1 expression and PGE2 synthesis detected by RT-PCR, Western blot, and ELISA in the endometrial tissue. The expression and synthesis were dramatically decreased by TLR4, myeloid differentiation factor88 (MyD88), and p38 mitogen-activated protein kinase (MAPK) inhibitors in E. coli-infected endometrial tissue. These inhibitors also significantly decreased proinflammatory factor (interleukin-6 and tumor necrosis factor-α) and damage-associated molecular pattern (high mobility group box-1 and hyaluronan-binding protein-1) release and tissue damage measured by double-label immunofluorescence in E. coli-infected endometrial explants. Our work provides in vitro evidence that TLR2/4-MyD88/p38 MAPK promotes PGE2 synthesis and E. coli-infected endometrial tissue damage, which may be useful for improving PGE2-based therapies for endometritis.

Combinative treatment of ß-elemene and cetuximab is sensitive to KRAS mutant colorectal cancer cells by inducing ferroptosis and inhibiting epithelial-mesenchymal transformation.

Background and Purpose: RAS mutations limit the effectiveness of anti-epidermal growth factor receptor (EGFR) monoclonal antibodies in combination with chemotherapy for metastatic colorectal cancer (mCRC) patients. Therefore, new cell death forms have focused on identifying indirect targets to inhibit Ras-induced oncogenesis. Recently, emerging evidence has shown the potential of triggering ferroptosis for cancer therapy, particularly for eradicating aggressive malignancies that are resistant to traditional therapies. Methods: KRAS mutant CRC cell HCT116 and Lovo were treated with cetuximab and ß-elemene, a bioactive compound isolated from Chinese herb Curcumae Rhizoma. Ferroptosis and epithelial-mesenchymal transformation (EMT) were detected in vitro and in vivo. Orthotopic CRC animal model were established and the tumor growth was monitored by IVIS bioluminescence imaging. Tumor tissues were collected to determine ferroptosis effect and the expression of EMT markers after the treatment. Results: CCK-8 assay showed that synergetic effect was obtained when 125 µg/ml ß-elemene was combined with 25 µg/ml cetuximab in KRAS mutant CRC cells. AV/PI staining suggested a non-apoptotic mode of cell death after the treatment with ß-elemene and cetuximab. In vitro, ß-elemene in combination with cetuximab was shown to induce iron-dependent reactive oxygen species (ROS) accumulation, glutathione (GSH) depletion, lipid peroxidation, upregulation of HO-1 and transferrin, and downregulation of negative regulatory proteins for ferroptosis (GPX4, SLC7A11, FTH1, glutaminase, and SLC40A1) in KRAS mutant CRC cells. Meanwhile, combinative treatment of ß-elemene and cetuximab inhibited cell migration and decreased the expression of mesenchymal markers (Vimentin, N-cadherin, Slug, Snail and MMP-9), but promoted the expression of epithelial marker E-cadherin. Moreover, ferroptosis inhibitors but not other cell death suppressors abrogated the effect of ß-elemene in combination with cetuximab on KRAS mutant CRC cells. In vivo, co-treatment with ß-elemene and cetuximab inhibited KRAS mutant tumor growth and lymph nodes metastases. Conclusions: Our data for the first time suggest that the natural product ß-elemene is a new ferroptosis inducer and combinative treatment of ß-elemene and cetuximab is sensitive to KRAS mutant CRC cells by inducing ferroptosis and inhibiting EMT, which will hopefully provide a prospective strategy for CRC patients with RAS mutations.

Preparation, characterization, pharmacokinetics and anticancer effects of PEGylated ß-elemene liposomes.

Objective: This study aimed to develop a new polyethylene glycol (PEG)ylated ß-elemene liposome (PEG-Lipo-ß-E) and evaluate its characterization, pharmacokinetics, antitumor effects and safety in vitro and in vivo. Methods: The liposomes were prepared by ethanol injection and high-pressure micro-jet homogenization. Characterization of the liposomes was conducted, and drug content, entrapment efficiency (EE), in vitro release and stability were studied by ultra-fast liquid chromatography (UFLC) and a liquid surface method. Blood was drawn from rats to establish the pharmacokinetic parameters. The anticancer effect was evaluated in a KU-19-19 bladder cancer xenograft model. Histological analyses were performed to evaluate safety. Results: The PEG-Lipo-ß-E showed good stability and was characterized as 83.31 ± 0.181 nm in size, 0.279 ± 0.004 in polydispersity index (PDI), -21.4 ± 1.06 mV in zeta potential, 6.65 ± 0.02 in pH, 5.024 ± 0.107 mg/mL in ß-elemene (ß-E) content, and 95.53 ± 1.712% in average EE. The Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC) indicated the formation of PEG-Lipo-ß-E. Compared to elemene injection, PEG-Lipo-ß-E demonstrated a 1.75-fold decrease in clearance, a 1.62-fold increase in half-life, and a 1.76-fold increase in area under the concentration-time curves (AUCs) from 0 hour to 1.5 hours (P < 0.05). PEG-Lipo-ß-E also showed an enhanced anticancer effect in vivo. Histological analyses showed that there was no evidence of toxicity to the heart, kidney, liver, lung or spleen. Conclusions: The present study demonstrates PEG-Lipo-ß-E as a new formulation with ease of preparation, high EE, good stability, improved bioavailability and antitumor effects.

All-stage precisional glioma targeted therapy enabled by a well-designed D-peptide.

Uncontrollable cell proliferation and irreversible neurological damage make glioma one of the most deadly diseases in clinic. Besides the multiple biological barriers, glioma stem cells (GSCs) that are responsible for the maintenance and recurrence of tumor tissues also hinder the therapeutic efficacy of chemotherapy. Therefore, all-stage precisional glioma targeted therapy regimens that could efficiently deliver drugs to glioma cells and GSCs after overcoming multiple barriers have received increasing scrutiny. Methods: A polymeric micelle-based drug delivery system was developed by modifying a "Y-shaped" well-designed ligand of both GRP78 protein and quorum sensing receptor to achieve all-stage precisional glioma targeting, then we evaluated the targeting ability and barrier penetration ability both in vitro and in vivo. In order to achieve all-stage precisional therapy, we need kill both GSCs and glioma related cells. Parthenolide (PTL) has been investigated for its selective toxicity to glioma stem cells while Paclitaxel (PTX) and Temozolomide (TMZ) are widely used in experimental and clinical therapy of glioma respectively. So the in vivo anti-glioma effect of combination therapy was evaluated by Kaplan-Meier survival analysis and immunohistochemical (IHC) examination of tumor tissues. Results: The "Y-shaped" well-designed peptide, termed DWVAP, exhibited excellent glioma (and GSCs) homing and barrier penetration ability. When modified on micelle surface, DWVAP peptide significantly enhanced accumulation of micelles in brain and glioma. In addition, DWVAP micelles showed no immunogenicity and cytotoxicity, which could guarantee their safety when used in vivo. Treatment of glioma-bearing mice with PTL loaded DWVAP modified PEG-PLA micelles plus PTX loaded DWVAP modified PEG-PLA micelles or PTL loaded DWVAP modified PEG-PLA micelles plus TMZ showed improved anti-tumor efficacy in comparison to PTL and PTX loaded unmodified micelles or PTL loaded unmodified micelles plus TMZ. Conclusion: Combination of all-stage targeting strategy and concomitant use of chemotherapeutics and stem cell inhibitors could achieve precise targeted therapy for glioma.