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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 -
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 -
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 -
BioMed Research International 2016QC4 is the derivative of rosin's main components dehydroabietic acid (DHA). We investigated the cytotoxic effect of QC4 on gastric cancer cells and revealed the...
AIM
QC4 is the derivative of rosin's main components dehydroabietic acid (DHA). We investigated the cytotoxic effect of QC4 on gastric cancer cells and revealed the mechanisms beneath the induction of cell death.
METHODS
The cytotoxic effect of QC4 on gastric cancer cells was evaluated by CCK-8 assay and flow cytometry. The underlying mechanisms were tested by administration of cell death related inhibitors and detection of apoptotic and oncosis related proteins. Cytomembrane integrity and organelles damage were confirmed by lactate dehydrogenase (LDH) leakage assay, mitochondrial function test, and cytosolic free Ca(2+) concentration detection.
RESULTS
QC4 inhibited cell proliferation dose- and time-dependently and destroyed cell membrane integrity, activated calpain-1 autolysis, and induced apoptotic protein cleavage in gastric cancer cells. The detection of decreased ATP and mitochondrial membrane potential, ROS accumulation, and cytosolic free Ca(2+) elevation confirmed organelles damage in QC4-treated gastric cancer cells.
CONCLUSIONS
DHA derivative QC4 induced the damage of cytomembrane and organelles which finally lead to oncosis and apoptosis in gastric cancer cells. Therefore, as a derivative of plant derived small molecule DHA, QC4 might become a promising agent in gastric cancer therapy.
Topics: Abietanes; Antineoplastic Agents; Apoptosis; Cell Line, Tumor; Cell Proliferation; Humans; Stomach Neoplasms
PubMed: 27057539
DOI: 10.1155/2016/2581061 -
Cell Death & Disease Jan 2016The proinflammatory interleukin-33 (IL-33) binds to its receptor ST2L on the surface of immune cells and stimulates the production of Th2 cytokines; however, the effects...
The proinflammatory interleukin-33 (IL-33) binds to its receptor ST2L on the surface of immune cells and stimulates the production of Th2 cytokines; however, the effects of IL-33 on tumour cells are poorly understood. Here we show that ST2 was significantly downregulated in human lung cancer tissues and cells compared with normal lung tissues and cells. IL-33 expression was also inversely correlated with the stages of human lung cancers. In accordance with this finding, low-metastatic cells but not high-metastatic cells derived from Lewis lung carcinoma expressed functional ST2L. IL-33 was abundantly present in the tumours established by the low-metastatic cells compared with those formed by the high-metastatic cells. Although the low-metastatic cells scarcely expressed IL-33 in vitro, these cells did expry 6ess this molecule in vivo, likely due to stimulation by intratumoural IL-1β and IL-33. Importantly, IL-33 enhanced the cell death of ST2L-positive low-metastatic cells, but not of ST2L-negative high-metastatic cells, under glucose-depleted, glutamine-depleted and hypoxic conditions through p38 MAPK and mTOR activation, and in a mitochondria-dependent manner. The cell death was characterised by cytoplasmic blisters and karyolysis, which are unique morphological features of oncosis. Inevitably, the low-metastatic cells, but not of the high-metastatic cells, grew faster in IL-33(-/-) mice than in wild-type mice. Furthermore, IL-33 selected for the ST2L-positive, oncosis-resistant high-metastatic cells under conditions mimicking the tumour microenvironment. These data suggest that IL-33 enhances lung cancer progression by selecting for more malignant cells in the tumour microenvironment.
Topics: Animals; Humans; Interleukin-33; Lung Neoplasms; Mice; Neoplasm Metastasis; Transfection; Tumor Microenvironment
PubMed: 26775708
DOI: 10.1038/cddis.2015.418 -
Macrophage Apr 2015Macrophage-pathogen interaction is a complex process and the outcome of this tag-of-war for both sides is to live or die. Without attempting to be comprehensive, this...
Macrophage-pathogen interaction is a complex process and the outcome of this tag-of-war for both sides is to live or die. Without attempting to be comprehensive, this review will discuss the complexity and significance of the interaction outcomes between macrophages and some facultative intracellular bacterial pathogens as exemplified by and . Upon bacterial infection, macrophages can die by a variety of ways, such as apoptosis, autophagic cell death, necrosis, necroptosis, oncosis, pyronecrosis, pyroptosis , which is the focus of this review.
PubMed: 26690967
DOI: 10.14800/Macrophage.779 -
Oncotarget Oct 2015Despite advances in the development of molecularly targeted therapies, metastatic renal cell carcinoma (RCC) is still incurable. Artesunate (ART), a well-known...
Repurposing the anti-malarial drug artesunate as a novel therapeutic agent for metastatic renal cell carcinoma due to its attenuation of tumor growth, metastasis, and angiogenesis.
Despite advances in the development of molecularly targeted therapies, metastatic renal cell carcinoma (RCC) is still incurable. Artesunate (ART), a well-known anti-malarial drug with low toxicity, exhibits highly selective anti-tumor actions against various tumors through generation of cytotoxic carbon-centered free radical in the presence of free iron. However, the therapeutic efficacy of ART against metastatic RCC has not yet been fully elucidated. In the analysis on a dataset from The Cancer Genome Atlas (TCGA) (n = 469) and a tissue microarray set from Samsung Medical Center (n = 119) from a cohort of patients with clear cell RCC (ccRCC), up-regulation of transferrin receptor 1 (TfR1), which is a well-known predictive marker for ART, was correlated with the presence of distant metastasis and an unfavorable prognosis. Moreover, ART exerted potent selective cytotoxicity against human RCC cell lines (Caki-1, 786-O, and SN12C-GFP-SRLu2) and sensitized these cells to sorafenib in vitro, and the extent of ART cytotoxicity correlated with TfR1 expression. ART-mediated growth inhibition of human RCC cell lines was shown to result from the induction of cell cycle arrest at the G2/M phase and oncosis-like cell death. Furthermore, ART inhibited cell clonogenicity and invasion of human RCC cells and anti-angiogenic effects in vitro in a dose-dependent manner. Consistent with these in vitro data, anti-tumor, anti-metastatic and anti-angiogenic effects of ART were also validated in human 786-O xenografts. Taken together, ART is a promising novel candidate for treating human RCC, either alone or in combination with other therapies.
Topics: Animals; Antigens, CD; Antimalarials; Antineoplastic Agents; Artemisinins; Artesunate; Carcinoma, Renal Cell; Cell Death; Cell Line, Tumor; Cell Proliferation; Female; Human Umbilical Vein Endothelial Cells; Humans; Kidney Neoplasms; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Invasiveness; Neoplasm Metastasis; Neovascularization, Pathologic; Prognosis; Reactive Oxygen Species; Receptors, Transferrin; Xenograft Model Antitumor Assays
PubMed: 26426994
DOI: 10.18632/oncotarget.5422 -
Molecular Medicine Reports Oct 2015Previous studies have reported the antitumor activity of N‑Myc downstream‑regulated gene 2 (NDRG2), a novel p53‑inducible gene, in several types of cancer. The...
Previous studies have reported the antitumor activity of N‑Myc downstream‑regulated gene 2 (NDRG2), a novel p53‑inducible gene, in several types of cancer. The present study aimed to investigate the effects of NDRG2 expression on the proliferation of a human bladder cancer cell line. NDRG2 and control green fluorescent protein (GFP) recombinant adenovirus plasmids were constructed and transfected into a bladder cancer cell line with mutant p53 (T24 cells). NDRG2 expression was analyzed using western blot analysis and immunofluorescence assay (IFA); in addition, the subcellular localization of NDRG2 was detected using a confocal microscope. The proliferation rate of cells was measured using colony formation and MTT assays. Furthermore, the cell cycle of transfected T24 cells was detected by flow cytometry. The results indicated that T24 cells expressed low levels of NDRG2 prior to infection with GFP‑NDRG2 recombinant adenovirus; by contrast, following infection, NDRG2 was primarily overexpressed in mitochondria. The proliferation rate of T24 cells was significantly reduced by NDRG2 expression (P<0.01). In addition, 82.1% of NDRG2‑expressing cells were in S‑phase, compared to 74.4% in the control virus‑infected cells (P<0.05). Furthermore, upregulation of NDRG2 induced an increase in oncosis, rather than apoptosis, in T24 cell. In conclusion, the results of the present study indicated that NDRG2 expression in mitochondria may arrest bladder cancer cells in S‑phase as well as decrease cell proliferation through inducing oncosis. It was therefore proposed that NDRG2 was not only a biomarker, but also a tumor suppressor for bladder cancer.
Topics: Adenoviridae; Cell Death; Cell Line, Tumor; Cell Proliferation; Epithelial Cells; Gene Expression Regulation, Neoplastic; Genes, Reporter; Genetic Vectors; Green Fluorescent Proteins; Humans; Mitochondria; Osmotic Pressure; S Phase Cell Cycle Checkpoints; Signal Transduction; Tumor Suppressor Protein p53; Tumor Suppressor Proteins; Urinary Bladder
PubMed: 26239274
DOI: 10.3892/mmr.2015.4169 -
Genetics and Molecular Research : GMR Jul 2015We aimed to evaluate the effect of melatonin on myo-cardial cell oncosis in the myocardial ischemia/reperfusion injury rat, and the role of the mitochondrial...
We aimed to evaluate the effect of melatonin on myo-cardial cell oncosis in the myocardial ischemia/reperfusion injury rat, and the role of the mitochondrial permeability transition pore (MPTP) therein. Sprague Dawley rats (N = 60) were randomly divided into five groups of 12 rats each: control, ischemia/reperfusion (I/R), melatonin treatment (MT), melatonin treatment + atractyloside (MT+ATR), and atractyloside (ATR). We prepared the myocardial ischemia/reperfusion model by reperfusion after the left anterior descending coronary artery was ligated for 30 min. The MT rats were given a 10 mg/kg MT intra-venous injection immediately thereafter; the MT+ATR rats were also given a 5 mg/kg ATR intravenous injection 15 min before the ischemia; the ATR rats were given the ATR injection only. After 2-h re-perfusion, myocardial tissue was extracted, the infarction size was determined, and myocardial ultrastructures were observed using electron microscopy. The expression level of the preoncosis receptor (porimin), which can induce membrane injury, was determined by western blot; the nicotinamide adenine dinucleotide (NAD(+)) content was determined spectrophotometrically. The four treatment groups showed upregulat-ed expression of myocardial porimin, increased myocardial infarction size, and reduced NAD(+) content (P < 0.05). Compared with the I/R and MT+ATR groups, MT rats showed downregulated expression of myo-cardial porimin, reduced myocardial infarct size, and increased myo-cardial cell NAD(+) content (P < 0.05). The above indices between the ATR and MT+ATR groups were not significantly different (P > 0.05). Thus, MT might protect myocardial ischemia/reperfusion rats by inhibiting MPTP opening and reducing myocardial cell oncosis.
Topics: Animals; Male; Melatonin; Mitochondrial Membrane Transport Proteins; Mitochondrial Permeability Transition Pore; Myocardial Infarction; Myocardial Reperfusion Injury; Myocardium; NAD; Rats, Sprague-Dawley; Receptors, Cell Surface
PubMed: 26214427
DOI: 10.4238/2015.July.3.24