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Nanoscale Research Letters Dec 2017Artemisinin and its derivatives were considered to exert a broad spectrum of anti-cancer activities, and they induced significant anti-cancer effects in tumor cells....
Artemisinin and its derivatives were considered to exert a broad spectrum of anti-cancer activities, and they induced significant anti-cancer effects in tumor cells. Artemisinin and its derivatives could be absorbed quickly, and they were widely distributed, selectively killing tumor cells. Since low concentrations of artesunate primarily depended on oncosis to induce cell death in tumor cells, its anti-tumor effects were undesirable and limited. To obtain better anti-tumor effects, in this study, we took advantage of a new nanotechnology to design novel artesunate-loaded bovine serum albumin nanoparticles to achieve the mitochondrial accumulation of artesunate and induce mitochondrial-mediated apoptosis. The results showed that when compared with free artesunate's reliance on oncotic death, artesunate-loaded bovine serum albumin nanoparticles showed higher cytotoxicity and their significant apoptotic effects were induced through the distribution of artesunate in the mitochondria. This finding indicated that artesunate-loaded bovine serum albumin nanoparticles damaged the mitochondrial integrity and activated mitochondrial-mediated cell apoptosis by upregulating apoptosis-related proteins and facilitating the rapid release of cytochrome C.
PubMed: 28610396
DOI: 10.1186/s11671-017-2169-7 -
Cell Death and Differentiation Apr 2017Pyroptosis is a lytic form of cell death distinguished from apoptosis, ferroptosis, necrosis, necroptosis, NETosis, oncosis, pyronecrosis and autophagy. Proinflammatory... (Review)
Review
Pyroptosis is a lytic form of cell death distinguished from apoptosis, ferroptosis, necrosis, necroptosis, NETosis, oncosis, pyronecrosis and autophagy. Proinflammatory caspases cleave a gasdermin D (GSDMD) protein to generate a 31 kDa N-terminal domain. The cleavage relieves the intramolecular inhibition on the gasdermin-N domain, which then moves to the plasma membrane to exhibit pore-forming activity. Thus, GSDMD acts as the final and direct executor of pyroptotic cell death. Owing to the selective targeting of the inner leaflet of the plasma membrane with the pore-forming that determines pyroptotic cell death, GSDMD could be a potential target to control cell death or extracellular bacterial infections. Intriguingly, other gasdermin family members also share similar N-terminal domains, but they present different cell death programs. Herein, we summarize features and functions of the novel player proteins in cell death, including GSDMD triggering pyroptosis, Gsdma3/GSDMA initiating autophagy/apoptosis and DFNA5 inducing apoptosis/secondary necrosis. The gasdermin N terminus appears to be a novel pore-forming protein. This provides novel insight into the underlying roles and mechanisms of lytic or nonlytic forms of programmed cell death, as well as their potential applications in inflammation-associated diseases.
Topics: Autophagy; Caspases; Humans; Intracellular Signaling Peptides and Proteins; Neoplasm Proteins; Phosphate-Binding Proteins; Pyroptosis; Receptors, Estrogen; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Signal Transduction; Transforming Growth Factor beta
PubMed: 28362726
DOI: 10.1038/cdd.2017.24 -
Molecular Therapy Oncolytics Mar 2017Enadenotucirev (EnAd) is a chimeric group B adenovirus isolated by bioselection from a library of adenovirus serotypes. It replicates selectively in and kills a diverse...
Enadenotucirev (EnAd) is a chimeric group B adenovirus isolated by bioselection from a library of adenovirus serotypes. It replicates selectively in and kills a diverse range of carcinoma cells, shows effective anticancer activity in preclinical systems, and is currently undergoing phase I/II clinical trials. EnAd kills cells more quickly than type 5 adenovirus, and speed of cytotoxicity is dose dependent. The EnAd death pathway does not involve p53, is predominantly caspase independent, and appears to involve a rapid fall in cellular ATP. Infected cells show early loss of membrane integrity; increased exposure of calreticulin; extracellular release of ATP, HSP70, and HMGB1; and influx of calcium. The virus also causes an obvious single membrane blister reminiscent of ischemic cell death by oncosis. In human tumor biopsies maintained in ex vivo culture, EnAd mediated release of pro-inflammatory mediators such as TNF-α, IL-6, and HMGB1. In accordance with this, EnAd-infected tumor cells showed potent stimulation of dendritic cells and CD4 T cells in a mixed tumor-leukocyte reaction in vitro. Whereas many viruses have evolved for efficient propagation with minimal inflammation, bioselection of EnAd for rapid killing has yielded a virus with a short life cycle that combines potent cytotoxicity with a proinflammatory mechanism of cell death.
PubMed: 28345021
DOI: 10.1016/j.omto.2016.11.003 -
Seminars in Cancer Biology Oct 2017Artemisia annua L. is used throughout Asia and Africa as tea and press juice to treat malaria and related symptomes (fever, chills). Its active ingredient, artemisinin... (Review)
Review
Artemisia annua L. is used throughout Asia and Africa as tea and press juice to treat malaria and related symptomes (fever, chills). Its active ingredient, artemisinin (ARS), has been developed as antimalarial drug and is used worldwide. Interestingly, the bioactivity is not restricted to malaria treatment. We and others found that ARS-type drugs also reveal anticancer in vitro and in vivo. In this review, we give a systematic overview of the literature published over the past two decades until the end of 2016. Like other natural products, ARS acts in a multi-specific manner against tumors. The cellular response of ARS and its derivatives (dihydroartemisinin, artesunate, artemether, arteether) towards cancer cells include oxidative stress response by reactive oxygen species and nitric oxide, DNA damage and repair (base excision repair, homologous recombination, non-homologous end-joining), various cell death modes (apoptosis, autophagy, ferroptosis, necrosis, necroptosis, oncosis), inhibition of angiogenesis and tumor-related signal transduction pathways (e.g. Wnt/β-catenin pathway, AMPK pathway, metastatic pathways, and others) and signal transducers (NF-κB, MYC/MAX, AP-1, CREBP, mTOR etc). ARS-type drugs are at the stairways to the clinics. Several published case reports and pilot phase I/II trials indicate clinical anticancer activity of these compounds. Because of unexpected cases of hepatotoxicity, combinations of ARS-type drugs with complementary and alternative medicines are not recommended, until controlled clinical trials will prove the safety of non-approved combination treatments.
Topics: Artemisia annua; Artemisinins; Gene Expression Regulation, Neoplastic; Humans; Neoplasm Proteins; Neoplasms; Oxidative Stress
PubMed: 28254675
DOI: 10.1016/j.semcancer.2017.02.009 -
Cell Death and Differentiation Mar 2017Antibody-mediated cell killing has significantly facilitated the elimination of undesired cells in therapeutic applications. Besides the well-known Fc-dependent...
Antibody-mediated cell killing has significantly facilitated the elimination of undesired cells in therapeutic applications. Besides the well-known Fc-dependent mechanisms, pathways of antibody-induced apoptosis were also extensively studied. However, with fewer studies reporting the ability of antibodies to evoke an alternative form of programmed cell death, oncosis, the molecular mechanism of antibody-mediated oncosis remains underinvestigated. In this study, a monoclonal antibody (mAb), TAG-A1 (A1), was generated to selectively kill residual undifferentiated human embryonic stem cells (hESC) so as to prevent teratoma formation upon transplantation of hESC-derived products. We revealed that A1 induces hESC death via oncosis. Aided with high-resolution scanning electron microscopy (SEM), we uncovered nanoscale morphological changes in A1-induced hESC oncosis, as well as A1 distribution on hESC surface. A1 induces hESC oncosis via binding-initiated signaling cascade, most likely by ligating receptors on surface microvilli. The ability to evoke excess reactive oxygen species (ROS) production via the Nox2 isoform of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase is critical in the cell death pathway. Excess ROS production occurs downstream of microvilli degradation and homotypic adhesion, but upstream of actin reorganization, plasma membrane damage and mitochondrial membrane permeabilization. To our knowledge, this is the first mechanistic model of mAb-induced oncosis on hESC revealing a previously unrecognized role for NAPDH oxidase-derived ROS in mediating oncotic hESC death. These findings in the cell death pathway may potentially be exploited to improve the efficiency of A1 in eliminating undifferentiated hESC and to provide insights into the study of other mAb-induced cell death.
Topics: Actins; Antibodies, Monoclonal; Apoptosis; Carbohydrate Sequence; Cell Line; Cell Membrane; Epitopes; Human Embryonic Stem Cells; Humans; Microscopy, Electron, Scanning; Mitochondrial Membranes; NADPH Oxidase 2; Permeability; Reactive Oxygen Species
PubMed: 28106884
DOI: 10.1038/cdd.2016.164 -
Oncoscience 2016High frequency quantitative ultrasound techniques were investigated to characterize different forms of cell death . Suspension-grown acute myeloid leukemia cells were...
High frequency quantitative ultrasound techniques were investigated to characterize different forms of cell death . Suspension-grown acute myeloid leukemia cells were treated to cause apoptosis, oncosis, mitotic arrest, and heat-induced death. Samples were scanned with 20 and 40 MHz ultrasound and assessed histologically in terms of cellular structure. Frequency-domain analysis of 20 MHz ultrasound data demonstrated midband fit changes of 6.0 ± 0.7 dBr, 6.2 ± 1.8 dBr, 4.0 ± 1.0 dBr and -4.6 ± 1.7 dBr after 48-hour cisplatinum-induced apoptosis, 48-hour oncotic decay, 36-hour colchicine-induced mitotic arrest, and heat treatment compared to control, respectively. Trends from 40 MHz ultrasound were similar. Spectral slope changes obtained from 40 MHz ultrasound data were reflective of alterations in cell and nucleus size. Chromatin pyknosis or lysis trends suggested that the density of nuclear material may be responsible for observed changes in ultrasound backscatter. Flow cytometry analysis confirmed the modes of cell death and supported midband fit trends in ultrasound data. Scatterer-size and concentration estimates obtained from a fluid-filled sphere form factor model further corresponded with spectral analysis and histology. Results indicate quantitative ultrasound spectral analysis may be used for probing anti-cancer response and distinguishing various modes of cell death .
PubMed: 28050578
DOI: 10.18632/oncoscience.319 -
ACS Applied Materials & Interfaces Nov 2016Photodynamic therapy (PDT) has shown great potential for overcoming drug-resistant cancers. Here, we report a multifunctional drug delivery system based on chlorin e6...
Photodynamic therapy (PDT) has shown great potential for overcoming drug-resistant cancers. Here, we report a multifunctional drug delivery system based on chlorin e6 (Ce6)/folic acid (FA)-loaded branched polyethylenimine-PEGylation ceria nanoparticles (PPCNPs-Ce6/FA), which was developed for targeted PDT to overcome drug-resistant breast cancers. Nanocarrier delivery and FA targeting significantly promoted the cellular uptake of photosensitizers (PSs), followed by their accumulation in lysosomes. PPCNPs-Ce6/FA generated reactive oxygen species (ROS) after near-infrared irradiation (NIR, 660 nm), leading to reduced P-glycoprotein (P-gp) expression, lysosomal membrane permeabilization (LMP), and excellent phototoxicity toward resistant MCF-7/ADR cells, even at ultralow doses. Moreover, we identified NIR-triggered lysosomal-PDT using the higher dose of PPCNPs-Ce6/FA, which stimulated cell death by plasma membrane blebbing, cell swelling, and energy depletion, indicating an oncosis-like cell death pathway, despite the occurrence of apoptotic or autophagic mechanisms at lower drug doses. In vivo studies showed prolonged blood circulation times, low toxicity in mice, and high tumor accumulation of PPCNPs-Ce6/FA. In addition, using NIR-triggered PDT, PPCNPs-Ce6/FA displayed excellent potency for tumor regression in the MCF-7/ADR xenograft murine model. This study suggested that multifunctional PPCNPs-Ce6/FA nanocomposites are a versatile and effective drug delivery system that may potentially be exploited for phototherapy to overcome drug-resistant cancers, and the mechanisms of cell death induced by PDT should be considered in the design of clinical protocols.
Topics: Animals; Breast Neoplasms; Cell Line, Tumor; Cerium; Humans; Mice; Photochemotherapy; Photosensitizing Agents; Porphyrins
PubMed: 27933980
DOI: 10.1021/acsami.6b07338 -
Molecular Cancer Therapeutics Jan 2017RAS oncogenic mutations are common in human cancers, but RAS proteins have been difficult to target. We sought to identify pharmacological agents to block RAS oncogenic...
RAS oncogenic mutations are common in human cancers, but RAS proteins have been difficult to target. We sought to identify pharmacological agents to block RAS oncogenic signaling by a distinct mechanism. Because the biological activity of RAS proteins relies upon lipid modifications and RAS regulates lipid metabolisms in cancer cells, we screened a bioactive lipid library using a RAS-specific cell viability assay. We report the discovery of a new class of inhibitors for RAS transformation. Compounds in the class represented by endocannabinoid N-arachidonoyl dopamine (NADA) can induce cell oncosis, independent of its ability to engage cannabinoid receptors. Further analyses show that NADA is more active in inhibiting the NRAS transformation and signaling than that of KRAS4B. Mechanistically, NADA blocks the plasma membrane translocation of NRAS, but not that of KRAS4B. In addition, NADA inhibits plasma membrane translocation and neoplastic transformation of oncogenic KRAS4A. Interestingly, NADA also redistributes the cytoplasmic NRAS to the Golgi apparatus in a palmitoylation-dependent manner. The results indicate that NADA inhibits NRAS and KRAS4A plasma membrane translocation by targeting a novel molecular process. The new findings would help to develop novel targeted therapies for a broad range of human cancers. Mol Cancer Ther; 16(1); 57-67. ©2016 AACR.
Topics: Animals; Antineoplastic Agents; Cell Line; Cell Membrane; Cell Transformation, Neoplastic; Cluster Analysis; Dopamine; Drug Discovery; Drug Screening Assays, Antitumor; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Golgi Apparatus; Humans; Mice; Protein Transport; Proto-Oncogene Proteins p21(ras); Receptors, Cannabinoid; Signal Transduction; TRPV Cation Channels
PubMed: 27760835
DOI: 10.1158/1535-7163.MCT-16-0419 -
Apoptosis : An International Journal on... Jul 2016To investigate the apoptotic effects of detergent sclerosants sodium tetradecylsulphate (STS) and polidocanol (POL) on endothelial cells at sub-lytic concentrations....
To investigate the apoptotic effects of detergent sclerosants sodium tetradecylsulphate (STS) and polidocanol (POL) on endothelial cells at sub-lytic concentrations. Human umbilical vein endothelial cells (HUVECs) were isolated and labelled with antibodies to assess for apoptosis and examined with confocal microscopy and flow cytometry. Isolated HUVECs viability was assessed using propidium iodide staining. Early apoptosis was determined by increased phosphatidylserine exposure by lactadherin binding. Caspase 3, 8, 9 and Bax activation as well as inhibitory assays with Pan Caspase (Z-VAD-FMK) and Bax (BI-6C9) were assessed to identify apoptotic pathways. Porimin activation was used to assess cell membrane permeability. Cell lysis reached almost 100 % with STS at 0.3 % and with POL at 0.6 %. Apoptosis was seen with both STS and POL at concentrations ranging from 0.075 to 0.15 %. PS exposure increased with both STS and POL and exhibited a dose-dependent trend. Active Caspase 3, 8 and 9 but not Bax were increased in HUVECs stimulated with low concentrations of both STS and POL. Inhibitory assays demonstrated Caspase 3, 8, 9 inhibition at low concentrations (0.075 to 0.6 %) with both STS and POL. Both agents increased the activation of porimin at all concentrations. Both sclerosants induced endothelial cell (EC) apoptosis at sub-lytic concentrations through a caspase-dependant pathway. Both agents induced EC oncosis.
Topics: Apoptosis; Borates; Caspase 3; Caspase 8; Caspase 9; Cells, Cultured; Detergents; Human Umbilical Vein Endothelial Cells; Humans; Polidocanol; Polyethylene Glycols; Sclerosing Solutions; Signal Transduction
PubMed: 27225250
DOI: 10.1007/s10495-016-1252-3 -
European Journal of Vascular and... Jun 2016The objective was to investigate the effects of the detergent sclerosants sodium tetradecyl sulfate (STS) and polidocanol (POL) on human leukocytes at sublytic...
OBJECTIVE/BACKGROUND
The objective was to investigate the effects of the detergent sclerosants sodium tetradecyl sulfate (STS) and polidocanol (POL) on human leukocytes at sublytic concentrations.
METHODS
Leukocytes were isolated and labelled with antibodies to assess for apoptosis and examined with confocal microscopy and flow cytometry. Isolated leukocyte count and viability was assessed using trypan blue, and propidium iodide staining. Phosphatidylserine (PS) exposure, a universal hallmark to measure cell apoptosis, was identified by flow cytometry using lactadherin. Caspases 3, 8, and 9, and Bax activation, as well as inhibitory assays with pan-caspase (Z-VAD-FMK) and Bax (BI-6C9) were assessed to determine apoptotic pathways. Porimin activation was used to assess cell permeability.
RESULTS
Up to 40% of leukocytes maintained membrane integrity at sublytic concentrations (≤0.15%) of sclerosants. The remaining 60% did not maintain membrane integrity but were not completely lysed. PS exposure was increased with both STS and POL exhibiting a dose- and time-dependant trend. While activation of caspases 3, 8, and 9, as well as Bax activation, were increased in leukocytes stimulated with low concentrations of STS, only caspases 3 and 9 and Bax were increased with POL. Inhibitory assays demonstrated caspases 3, 8, and 9, and Bax inhibition at low concentrations with both STS and POL. Both agents increased the leukocyte activation of porimin at all concentrations. On confocal microscopy, stains for caspases 3, 8, and 9, and Bax were increased for both STS and POL. Porimin stain was markedly positive for both STS and POL.
CONCLUSION
Both sclerosants induced leukocyte apoptosis at sublytic concentrations. STS activated both extrinsic and intrinsic pathways of apoptosis, while POL stimulated the intrinsic pathway of apoptosis only. Both agents induced oncosis. Based on these results, STS appears to have a greater effect than POL.
Topics: Apoptosis; Caspases; Detergents; Humans; Leukocytes; Necrosis; Polidocanol; Polyethylene Glycols; Sclerosing Solutions; Sodium Tetradecyl Sulfate
PubMed: 27067723
DOI: 10.1016/j.ejvs.2016.03.008