scholarly journals High Concentration of Aspirin Induces Apoptosis in Rat Tendon Stem Cells via Inhibition of the Wnt/β-Catenin Pathway

2018 ◽  
Vol 50 (6) ◽  
pp. 2046-2059 ◽  
Author(s):  
Yunjiao Wang ◽  
Hong Tang ◽  
Gang He ◽  
Youxing Shi ◽  
Xia Kang ◽  
...  
Keyword(s):  
Stem Cells ◽  
Flow Cytometry ◽  
Clinical Practice ◽  
Achilles Tendon ◽  
Western Blotting ◽  
Caspase 3 ◽  
Apoptosis Protein ◽  
Tendon Stem Cells ◽  
Cox 2 ◽  
Induced Apoptosis

Background/Aims: Non-steroidal anti-inflammatory drugs (NSAIDs) are commonly used in clinical practice to relieve fever and pain. Aspirin, as a representative NSAID, has been widely used in the treatment of tendinopathy. Some reports have demonstrated that aspirin can induce apoptosis in cancer cells. However, evidence regarding aspirin treatment for tendinopathy, especially the effect of this treatment on tendon stem cells (TSCs), is lacking. Understanding the effect of aspirin on tendinopathy may provide a basis for the rational use of NSAIDs in clinical practice. The aim of our study was to determine whether aspirin induces apoptosis in rat TSCs via the Wnt/β-catenin pathway. Methods: First, we used flow cytometry and fluorescence to detect TSC apoptosis. Protein expression of the apoptosis-related caspase-3 pathway was investigated via western blot analysis. Next, we used western blotting to determine the effect of aspirin on the Wnt/β-catenin pathway. We used immunostaining to detect the levels of Bcl2, cleaved caspase-3, and P-β-catenin in the Achilles tendon. Finally, we used flow cytometry, fluorescence, and western blotting to investigate the aspirin-induced apoptosis of TSCs via the Wnt/β-catenin pathway. Results: Aspirin induced morphological apoptosis in rat TSCs via the mitochondrial/caspase-3 pathway and induced cellular apoptosis in the Achilles tendon. Apoptosis was partly reversed after adding the Wnt signaling activator Wnt3a and lithium chloride (LiCl, a GSK-3β inhibitor). Aspirin administration led to a dose-dependent increase in COX-2 expression. Apoptosis was promoted after adding the COX-2 inhibitor NS398. Conclusion: The Wnt/β-catenin pathway plays a vital role in aspirin-induced apoptosis by regulating mitochondrial/caspase-3 function. Elevating COX-2 levels may protect cells against apoptosis. More importantly, the results remind us to consider the apoptotic effect of aspirin on TSCs and tendon cells when aspirin is administered to treat tendinopathy. The relationship between the positive and negative effects of aspirin remains a subject for future study.

scholarly journals α-bisabolol enhances radiotherapy-induced apoptosis in endometrial cancer cells by reducing the effect of XIAP on inhibiting caspase-3

2019 ◽  
Vol 39 (6) ◽  
Author(s):  
Dongmei Fang ◽  
Hongxin Wang ◽  
Min Li ◽  
Wenwen Wei
Keyword(s):  
Endometrial Cancer ◽  
Caspase 3 ◽  
Migration And Invasion ◽  
Inhibitor Of Apoptosis ◽  
Downstream Effectors ◽  
Apoptosis Protein ◽  
Ec Cells ◽  
Cox 2 ◽  
Matrix Metalloproteinases 9 ◽  
Induced Apoptosis

Abstract Endometrial cancer (EC) is one of the most common cancers in females. Although the diagnosis and treatment in early stages can greatly improve the survival rate of patients, the advanced EC still is lethal. Radiotherapy is widely used against EC, and it is a great challenge to find an effective way to overcome the resistance of EC during radiotherapy. α-bisabolol is a promising drug, which has already exhibited its anti-tumor effect in some malignancies. Here we reported that α-bisabolol could inhibit the proliferation of EC cells. It is also shown that their abilities of migration and invasion were effectively reduced by α-bisabolol. Furthermore, our results also demonstrated that α-bisabolol could improve sensitivity of EC cells in radiotherapy and further inhibited the growth of EC cells. By Western blot, we found the expression of matrix metalloproteinases-9 (MMP-9) and cyclin E were significantly decreased, which indicated that EC cells can be further suppressed by using α-bisabolol and radiotherapy. It is also demonstrated in our study that the rate of apoptotic cells is markedly increased in EC by using these two treatments. The significant decrease in X-linked inhibitor of apoptosis protein (XIAP) and increase in caspase-3 detected in our study suggested that the enhancement of apoptosis is mediated by XIAP/caspase-3 pathway, which was further confirmed by examining the downstream effectors of caspase-3, COX-2, PARP and cleaved PARP. In the present study, we demonstrated that α-bisabolol could enhance the sensitivity of EC cells to radiotherapy, which provide a novel alternative for overcoming radioresistance of EC cells and achieving a better outcome in radiotherapy.

scholarly journals Differential Expression of MicroRNA-19b Promotes Proliferation of Cancer Stem Cells by Regulating the TSC1/mTOR Signaling Pathway in Multiple Myeloma

2018 ◽  
Vol 50 (5) ◽  
pp. 1804-1814 ◽  
Author(s):  
Ni Wang ◽  
Xiaohua Liang ◽  
Weijian Yu ◽  
Shihang Zhou ◽  
Meiyun  Fang
Keyword(s):  
Stem Cells ◽  
Multiple Myeloma ◽  
Cancer Stem Cells ◽  
Real Time ◽  
Caspase 3 ◽  
In Silico Analysis ◽  
Luciferase Assay ◽  
Downstream Target ◽  
Induced Apoptosis

Background/Aims: MiR-19b has been reported to be involved in several malignancies, but its role in multiple myeloma (MM) is still unknown. The objective of this study was to explore the biological mechanism of miR-19b in the progression of MM. Methods: First, we performed real-time polymerase chain reaction (PCR) and Western blot to study the expression of miR-19b, tuberous sclerosis 1 (TSC1), and caspase-3 in different groups. MTT assay was performed to explore the effect of miR-19b on survival and apoptosis of cancer stem cells (CSCs). Computation analysis and luciferase assay were utilized to confirm the interaction between miR-19b and TSC1. Results: A total of 38 participants comprising 20 subjects with MM and 18 healthy subjects as normal controls were enrolled in our study. Real-time PCR showed dramatic upregulation of miR-19b, but TSC1 was evidently suppressed in the MM group. MiR-19b overexpression substantially promoted clonogenicity and cell viability, and further inhibited apoptosis of CSCs in vitro. Furthermore, miR-19b overexpression downregulated the expression of caspase-3, which induced apoptosis. Using in silico analysis, we identified that TSC1 might be a direct downstream target of miR-19b, and this was further confirmed by luciferase assay showing that miR-19b apparently reduced the luciferase activity of wild-type TSC1 3´-UTR, but not that of mutant TSC1 3´-UTR. There was also evident decrease in TSC1 mRNA and protein in CSCs following introduction of miR-19b. Interestingly, reintroduction of TSC1 abolished the miR-19b-induced proliferation promotion and apoptosis inhibition in CSCs. Conclusion: These findings collectively suggest that miR-19b promotes cell survival and suppresses apoptosis of MM CSCs via targeting TSC1 directly, indicating that miR-19b may serve as a potential and novel therapeutic target of MM based on miRNA expression.

scholarly journals Azithromycin Promotes the Osteogenic Differentiation of Human Periodontal Ligament Stem Cells after Stimulation with TNF-α

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Tingting Meng ◽  
Ying Zhou ◽  
Jingkun Li ◽  
Meilin Hu ◽  
Xiaomeng Li ◽  
...  
Keyword(s):  
Stem Cells ◽  
Alkaline Phosphatase ◽  
Osteogenic Differentiation ◽  
Alkaline Phosphatase Activity ◽  
Periodontal Ligament ◽  
Caspase 3 ◽  
Caspase 8 ◽  
Periodontal Ligament Stem Cells ◽  
Alizarin Red ◽  
Induced Apoptosis

Background and Objective. This study investigated the effects and underlying mechanisms of azithromycin (AZM) treatment on the osteogenic differentiation of human periodontal ligament stem cells (PDLSCs) after their stimulation with TNF-α in vitro. Methods. PDLSCs were isolated from periodontal ligaments from extracted teeth, and MTS assay was used to evaluate whether AZM and TNF-α had toxic effects on PDLSCs viability and proliferation. After stimulating PDLSCs with TNF-α and AZM, we analyzed alkaline phosphatase staining, alkaline phosphatase activity, and alizarin red staining to detect osteogenic differentiation. Real-time quantitative polymerase chain reaction (RT-qPCR) analysis was performed to detect the mRNA expression of osteogenic-related genes, including RUNX2, OCN, and BSP. Western blotting was used to measure the NF-κB signaling pathway proteins p65, phosphorylated p65, IκB-α, phosphorylated IκB-α, and β-catenin as well as the apoptosis-related proteins caspase-8 and caspase-3. Annexin V assay was used to detect PDLSCs apoptosis. Results. TNF-α stimulation of PDLSCs decreased alkaline phosphatase and alizarin red staining, alkaline phosphatase activity, and mRNA expression of RUNX2, OCN, and BSP in osteogenic-conditioned medium. AZM enhanced the osteogenic differentiation of PDLSCs that were stimulated with TNF-α. Western blot analysis showed that β-catenin, phosphorated p65, and phosphorylated IκB-α protein expression decreased in PDLSCs treated with AZM. In addition, pretreatment of PDLSCs with AZM (10 μg/ml, 20 μg/ml) prevented TNF-α-induced apoptosis by decreasing caspase-8 and caspase-3 expression. Conclusions. Our results showed that AZM promotes PDLSCs osteogenic differentiation in an inflammatory microenvironment by inhibiting the WNT and NF-κB signaling pathways and by suppressing TNF-α-induced apoptosis. This suggests that AZM has potential as a clinical therapeutic for periodontitis.

scholarly journals Short-Chain Fatty Acids Alleviate Hepatocyte Apoptosis Induced by Gut-Derived Protein-Bound Uremic Toxins

2021 ◽  
Vol 8 ◽  
Author(s):  
Mingjuan Deng ◽  
Xingqi Li ◽  
Weiwei Li ◽  
Jiahui Gong ◽  
Xiaoying Zhang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Caspase 3 ◽  
B Cell Lymphoma ◽  
Short Chain Fatty Acids ◽  
Uremic Toxins ◽  
Short Chain ◽  
Liver Carcinoma ◽  
Apoptosis Protein ◽  
Induced Apoptosis ◽  
Chain Fatty Acids

Chronic kidney disease (CKD) is characterized with the influx of uremic toxins, which impairs the gut microbiome by decreasing beneficial bacteria that produce short-chain fatty acids (SCFAs) and increasing harmful bacteria that produce gut-derived protein-bound uremic toxins (PBUTs). This study aimed to assess the proapoptotic effects of three major gut-derived PBUTs in hepatocytes, and the effects of SCFAs on apoptosis phenotype in vitro. HepG2 (human liver carcinoma cells) and THLE-2 (immortalized human normal liver cells) cell line were incubated with 0, 2, 20, 200, 2000 μM p-cresol sulfate (PCS), indoxyl sulfate (IS), and hippuric acid (HA), respectively, for 24 h. Flow cytometry analysis indicated that three uremic toxins induced varying degrees of apoptosis in hepatocytes and HA represented the highest efficacy. These phenotypes were further confirmed by western blot of apoptosis protein expression [Caspase-3, Caspase-9, B-cell lymphoma 2 (Bcl-2), and Bcl-2-associated X protein (Bax)]. Human normal hepatocytes (THLE-2) are more sensitive to PBUTs-induced apoptosis compared with human hepatoma cells (HepG2). Mechanistically, extracellular HA could enter hepatocytes, increase reactive oxygen species (ROS) generation, and decrease mitochondrial membrane potential dose-dependently in THLE-2 cells. Notably, coculture with SCFAs (acetate, propionate, butyrate) for 24 h significantly improved HA-induced apoptosis in THLE-2 cells, and propionate (500 μM) represented the highest efficacy. Propionate reduction of apoptosis was associated with improving mitochondria dysfunction and oxidative stress in a manner involving reducing Caspase-3 expression, ROS production, and increasing the Bcl-2/Bax level. As such, our studies validated PBUTs accumulation might be an important cause of liver dysfunction in patients with CKD, and supplementation of SCFAs might be a viable way to protect the liver for patients with CKD.

scholarly journals Assessment of aldehyde dehydrogenase in viable cells

Blood ◽  
1995 ◽  
Vol 85 (10) ◽  
pp. 2742-2746 ◽  
Author(s):  
RJ Jones ◽  
JP Barber ◽  
MS Vala ◽  
MI Collector ◽  
SH Kaufmann ◽  
...  
Keyword(s):  
Stem Cells ◽  
Bone Marrow ◽  
Flow Cytometry ◽  
Western Blotting ◽  
Aldehyde Dehydrogenase ◽  
Cell Populations ◽  
Intracellular Protein ◽  
Hematopoietic Progenitors ◽  
Hematopoietic Stem ◽  
Viable Cells

Cytosolic aldehyde dehydrogenase (ALDH), an enzyme responsible for oxidizing intracellular aldehydes, has an important role in ethanol, vitamin A, and cyclophosphamide metabolism. High expression of this enzyme in primitive stem cells from multiple tissues, including bone marrow and intestine, appears to be an important mechanism by which these cells are resistant to cyclophosphamide. However, although hematopoietic stem cells (HSC) express high levels of cytosolic ALDH, isolating viable HSC by their ALDH expression has not been possible because ALDH is an intracellular protein. We found that a fluorescent aldehyde, dansyl aminoacetaldehyde (DAAA), could be used in flow cytometry experiments to isolate viable mouse and human cells based on their ALDH content. The level of dansyl fluorescence exhibited by cells after incubation with DAAA paralleled cytosolic ALDH levels determined by Western blotting and the sensitivity of the cells to cyclophosphamide. Moreover, DAAA appeared to be a more sensitive means of assessing cytosolic ALDH levels than Western blotting. Bone marrow progenitors treated with DAAA proliferated normally. Furthermore, marrow cells expressing high levels of dansyl fluorescence after incubation with DAAA were enriched for hematopoietic progenitors. The ability to isolate viable cells that express high levels of cytosolic ALDH could be an important component of methodology for identifying and purifying HSC and for studying cyclophosphamide-resistant tumor cell populations.

Research of HIF-1 Mediated SDF-1/CXCR4 Axis on the Directional Migration and Neural Differentiation of Mesenchymal Stem Cells

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 4699-4699
Author(s):  
Qin Yu ◽  
Jie Lin ◽  
Lizhen Liu ◽  
Peipei Li ◽  
XiaoBo Xuan ◽  
...  
Keyword(s):  
Stem Cells ◽  
Flow Cytometry ◽  
Mesenchymal Stem Cells ◽  
Western Blotting ◽  
Protein Level ◽  
Neural Differentiation ◽  
Directional Migration ◽  
Protein Levels ◽  
Cxcr4 Mrna ◽  
Cxcr4 Axis

Abstract Abstract 4699 Introduction: Mesenchymal stem cells (MSCs) are under study as therapeutic delivery agents that assist in the repair of damaged tissues. At present, the mechanisms of targeted therapy of MSCs are known to relate with the hypoxia-inducible factor-1 (HIF-1) and its regulated biological axis stromal cell-derived factor-1/chemokine receptor 4 (SDF-1/CXCR4). SDF-1 and CXCR4 have a wide distribution in various cells and tissues, which plays an important role in the development of immune system, circulatory system and central nervous system. We thus inferred that SDF-1/CXCR4 may participate in the differentiation as well as the migration of stem cells. Our research aims to explore the effect of HIF-1α and its mediated SDF-1/CXCR4 axis on the directional migration and neural differentiation of MSCs, which may lead to a break in the efficiency and target distribution of MSCs therapy. Method: (1) Influence of hypoxia, CXCR4 antagonist (AMD3100) and SDF-1α on the proliferation of rat Mesenchymal Stem Cells (rMSCs): rMSCs were isolated from bone marrow of rats, and expanded in vitro. The growth feature of rMSCs exposed to hypoxia (PO2=1%) or normoxia was identified by growth curve, while the effect of AMD3100 (5ug/ml) and SDF-1α (10ng/ml and 100ng/ml) on the proliferation ability of rMSCs was detected by cell counting kit-8. (2) Effect of hypoxia on the expression of HIF-1α, CXCR4 and SDF-1α: Firstly, we used RT-PCR, western blotting and flow cytometry to detect the expression of HIF-1α and CXCR4 mRNA and protein levels in rMSCs which treated with hypoxia for 0h, 6h, 12h, 24h, 48h and 72h. Secondly, HIF-1α, SDF-1α mRNA and protein level in the hippocampus of rats which suffered hypoxia- ischemia for 1d, 3d, 5d, 7d, 14d and 21d were also detected by the same assays. (3) Research of HIF-1α and SDF-1/CXCR4 axis on the migration of rMSCs: We first detected the change of CXCR4 mRNA and protein levels in rMSCs treated with AMD3100 (5ug/ml) and SDF-1α (10ng/ml) by RT-PCR, western blotting and flow cytometry, and then studied SDF-1/CXCR4 axis on the migration of rMSCs using Transwell assay. (4) Effect of HIF-1α and SDF-1/CXCR4 axis on the differentiation of rMSCs: protein level of NSE and GFAP as well as positive rate of neural-induced rMSCs which have been pretreated with AMD3100 (5ug/ml) were detected by western blotting and immunocytochemistry. Results: Persistent hypoxia promoted the proliferation of rMSCs, while AMD3100 and SDF-1α at the concentration mentioned above had no effect. Compared to normal control, the protein expression of HIF-1α in rMSCs increased in hypoxic condition while the mRNA of HIF-1α did not change. Furthermore, the mRNA and protein level of CXCR4 both increased in rMSCs exposed to hypoxia for 6h and 12h, and the results confirmed by flow cytometry. We found HIF-1α mRNA was stably expressed in hippocampus, and increased significantly in hypoxia-ischemia brain damaged (HIBD) rats in a time dependent manner, which reached the peak on 7d. As expected, SDF-1α mRNA in hippocampus of HIBD rats was higher than that of normal control group, which reached the peak on 7d (P<0.01) and stably expressed till 21d, while the protein level is mainly in concordance. Moreover, CXCR4 mRNA was extremely up-regulated in rMSCs treated with SDF-1α (10ng/ml), however, in 5 ug/ml AMD3100 treated rMSCs, which decreased markedly (P<0.01), and the results were confirmed by western blotting and flow cytometry assays (P<0.05). Transwell assay manifested that SDF-1α had obvious chemotaxis to rMSCs. Protein level and positive cell number of NSE and GFAP were extremely down-regulated in rMSCs which pretreated with 5ug/ml AMD3100. Conclusion: Increased expression of HIF-1α led to the up-regulation of SDF-1/CXCR4 axis, and rMSCs displayed chemotaxis migration ascribed to the receptor-ligand interactions of SDF-1α and CXCR4, suggesting that HIF-1 and its mediated SDF-1/CXCR4 axis are of great significant on the directional migration of rMSCs. We also showed that CXCR4 antagonisation reduced the neural differentiation capabilities of rMSCs, thus suggested that SDF-1/CXCR4 axis may deeply involve in the neural differentiation of rMSCs. Disclosures: No relevant conflicts of interest to declare.

5-Azacytidine and Decitabine Induce Demethylation and Re-Expression of FAS (CD95) and Promote Apoptosis in Neoplastic Cells in Acute Myeloid Leukemia (AML),

Blood ◽  
2011 ◽  
Vol 118 (21) ◽  
pp. 3463-3463
Author(s):  
Heidrun Karlic ◽  
Rene Reitermaier ◽  
Viviane Ghanim ◽  
Harald Herrmann ◽  
Roman Thaler ◽  
...  
Keyword(s):  
Stem Cells ◽  
Flow Cytometry ◽  
Acute Myeloid Leukemia ◽  
Progenitor Cells ◽  
Myeloid Leukemia ◽  
Neoplastic Cells ◽  
Drug Induced ◽  
Secondary Aml ◽  
Induced Apoptosis ◽  
Acute Myeloid

Abstract Abstract 3463 Epigenetic and apoptosis-regulating mechanisms have been implicated as critical factors contributing to the progression from myelodysplastic syndromes (MDS) to secondary acute myeloid leukemia (AML). However, the exact molecular mechanisms and genes involved in disease evolution have not been identified yet. We screened for epigenetically regulated pro-apoptotic effector molecules in neoplastic cells in patients with MDS (n=50) and AML (n=30). Among a series of potential regulators, we identified FAS (CD95) as an epigenetically regulated critical death regulator in neoplastic cells. As assessed by qPCR, bone marrow cells obtained from patients with low risk MDS were found to display high levels of FAS, whereas FAS mRNA levels were lower or undetectable in patients with advanced MDS (with excess of blasts) or secondary AML. Moreover, we were able to show by multicolor flow cytometry that CD34+/CD38+ progenitor cells and CD34+/CD38- stem cells in MDS and AML display measurable FAS (CD95) on their surface, with slightly higher levels detectable in progenitor cells in low risk MDS compared to high risk MDS and secondary AML. Methylation-specific PCR and qPCR revealed that the FAS-promoter is hypermethylated in primary AML cells as well as in various AML cell lines including KG1 and HL60 thus repressing mRNA-synthesis. In addition, we found that exposure to 5-Azacytidine or Decitabine leads to demethylation of CpG-rich regions closest to the transcription starting sites, and thus to re-expression of FAS in AML cells. In vitro-targeting of AML cells by demethylating drugs was also found to revert epigenetic inactivation of other tumor suppressor genes such as CDKN2B (P15), CDKN2A (P16), ESR1 (estrogen-receptor alpha), with subsequent normalization of mRNA expression levels. Next, we asked whether CD95 acts as a critical death regulator involved in drug-induced apoptosis in neoplastic cells. In these experiments, both demethylating agents, 5-Azacytidine or Decitabine, were found to induce dose-dependent apoptosis and growth inhibition in primary AML cells, primary MDS cells, and in all AML cell lines examined. Drug-induced apoptosis in AML cells was accompanied by activation of caspase 8 and caspase 3 as well as increased expression of proapoptotic FAS/CD95 as determined by qPCR, Western blotting, and flow cytometry. Moreover, both drugs were found to induce expression of the FAS-ligand and DAPK1 in neoplastic cells. We then applied a siRNA against FAS. The siRNA-induced knock-down of FAS was found to block drug-induced FAS expression and FAS-induced apoptosis in KG1 cells and HL60 cells. In conclusion, our data show that FAS is hypermethylated in neoplastic cells in patients with advanced MDS and AML, that demethylating agents lead to re-expression of FAS, and that drug-induced FAS expression mediates apoptosis in leukemic cells. As FAS is also expressed on neoplastic stem cells, these observations may have clinical implications and may explain beneficial effects seen with 5-Azacytidine or Decitabine in patients with advanced MDS. Disclosures: Valent: Novartis: Consultancy, Honoraria, Research Funding.

Angelica Polysaccharide and TPO Have a Protective Effect On Hcmv-Induced Apoptosis In Megakaryocytes

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 3553-3553
Author(s):  
Mo Yang ◽  
Jian Liang Chen ◽  
Jie yu Ye ◽  
Su yi Li ◽  
En yu Liang ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Protective Effect ◽  
Caspase 3 ◽  
Hcmv Infection ◽  
Annexin V ◽  
Angelica Sinensis ◽  
Control Group ◽  
Mock Control ◽  
Apoptotic Effect ◽  
Induced Apoptosis

Abstract Human cytomegalovirus (hCMV) infection is often associated with thrombocytopenia. Megakaryocytes may be one of the major sites of hCMV infection, then inducing this cell apoptosis. Angelica Sinensis (Danggui) is an important ingredient of many commonly used herbal Medicine for promoting blood production. Our previous study has showed that the hematopoietic effect of Angelica Sinensis is related to its constituent, angelica polysaccharide (APS) (Yang M et al, J Ethnopharma, 2009). This present study investigated the anti-apoptotic effect of APS and TPO on hCMV-induced apoptosis in megakaryocytes. Human bone marrow mononuclear cells (MNC) or megakaryocytic cell line CHRF-288-11 and hCMV AD169 strain were co-cultured in this study. hCMV significantly inhibited the formation of CFU-MK as shown in three different concentrations of viral infection groups (103, 104 and 105 pfu/ml), compared with blank control and mock control (n=10, P<0.05). hCMV also significantly inhibited the growth of CHRF cells in these three different concentrations after incubation for 3 days, which compared with control group (n=10, P<0.01). hCMV DNA and mRNA were also positively detected in CHRF cells and the cells of CFU-MK with IS-PCR and RT-PCR respectively, while it was negative in blank and mock control groups. We further studied the effect of APS and TPO on CFU-MK formation. Results showed that APS (50 ug/ml) like TPO (50 ng/ml) enhanced hCMV-reduced CFU-MK (P=0.05, n=6). CHRF cells were also analyzed by Annexin V/PI with flow cytometry at day 3 after infection with hCMV AD169. The percentage of apoptotic cells in group of 103 pfu/ml was 19.0 ± 2.0%; The group of 104 pfu/ml was 23.0 ± 1.5%; The group of 105 pfu/ml was 28.0 ± 3.0%. The control group was 2.0 ± 0.5%. The apoptotic cells were confirmed by morphologic observation. In addition, apoptotic signals from megakaryocytic surface, cytoplasma and mitochondria were detected in hCMV infected cells by flow cytometry with Caspase-3 and JC-1 assay. Compared to mock infection control at day 5, Annexin-V positive cells population increased by 58%; active caspase-3 signal increased by 120% in viable cell population; and cell population with damaged mitochondial membrane showed a 5-times increase. Moreover, the anti-apoptotic effect of APS and TPO on CHRF cells was also demonstrated by using Annexin-V assay. Our studies showed that hCMV induces the apoptosis in megakaryocytes via mitochondrial and caspase-3 signaling, and angelica polysaccharide (APS) like TPO has a protective effect on hCMV-induced apoptosis in these cells. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Inhibition of Fatty Acid Oxidation with Avocatin B Selectively Targets AML Cells and Leukemia Stem Cells

Blood ◽  
2014 ◽  
Vol 124 (21) ◽  
pp. 268-268 ◽  
Author(s):  
Eric A Lee ◽  
Leonard Angka ◽  
Sarah-Grace Rota ◽  
Thomas Hanlon ◽  
Rose Hurren ◽  
...  
Keyword(s):  
Stem Cells ◽  
Flow Cytometry ◽  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Leukemia Cell ◽  
Leukemia Cells ◽  
Leukemia Stem Cells ◽  
Acid Oxidation ◽  
Selective Toxicity ◽  
Induced Apoptosis

Abstract Acute myeloid leukemia (AML) is an aggressive malignant disease characterized by poor patient outcome and suboptimal front-line chemotherapy. To identify novel anti-AML compounds, we performed a high-throughput screen of a natural products library (n=800). This screen was performed against the AML cell line (TEX), which has several properties of leukemia stem cells, the cells responsible for disease pathophysiology and patient relapse. Here, avocatin B was identified as a potent and novel anti-leukemia agent. Avocatin B, at concentrations as high as 20µM, had no effect on normal peripheral blood stem cell viability. In contrast, it induced death of primary AML cells with an EC50 of 1.5-5.0 µM. Selective toxicity towards a functionally defined subset of primitive leukemia cells was also demonstrated. Avocatin B (3µM) reduced clonogenic growth of AML progenitor cells with no effect on clonogenic growth of normal hematopoietic stem cells. Further, treatment of primary AML cells with avocatin B (3µM) diminished their ability to engraft into the bone marrow of pre-conditioned, NOD/SCID mice (t18=6.5; p<0.001). Together, these results confirm that avocatin B is a novel anti-AML agent with selective toxicity toward leukemia and leukemia stem cells. Mechanistically, avocatin B-induced reactive oxygen species (ROS)-dependent leukemia cell apoptosis that was characterized by the release of mitochondrial proteins, cytochrome c and apoptosis inducing factor (AIF). Cytochrome c and AIF were detected in the cytosol of avocatin B treated TEX cells by flow cytometry. Avocatin B-induced apoptosis, as measured by the Annexin V/Propidium iodide assay, DNA fragmentation and PARP cleavage, was abolished in the presence of anti-oxidants confirming the functional importance of ROS. Next, we further evaluated the role of mitochondria in avocatin B-induced apoptosis. First, we generated leukemia cells lacking mitochondria by successive culturing in media containing ethidium bromide. The drastic (>80%) reduction in mitochondria were confirmed by nonyl acridine orange staining and flow cytometry and a near absence of the mitochondria specific proteins ANT and ND1, as measured by Western blotting. Avocatin B’s activity was abolished in leukemia cells lacking mitochondria. Next, using lentiviral knockdown, we generated leukemia cells lacking CPT1, the enzyme that facilitates transport of 16-20 carbon lipids into mitochondria. Avocatin B’s activity was abolished in cells with reduced CPT1 expression (>70% as measured by qPCR analysis). To further confirm the importance of CPT1 in avocatin B-induced death, we chemically inhibited CPT1 with etomoxir. Avocatin B’s activity was blocked in the presence of etomoxir, further demonstrating that avocatin B accumulates in mitochondria. Since avocatin B is a lipid that targets mitochondria and that mitochondria can oxidize fatty acids for energy, we next assessed the impact of avocatin B on fatty acid oxidation, using the Seahorse Bioanalyzer. Avocatin B inhibited leukemia cell fatty acid oxidation (>40% reduction in oxygen consumption at 10µM) and this occurred at a 10-fold less concentration than etomoxir, the standard experimental molecule used to probe this pathway. Further, avocatin B resulted in a 50% reduction in levels of NADPH, an important co-factor generated during fatty acid oxidation that participates in catabolic processes during cell proliferation. These results show that avocatin B accumulates in mitochondria to inhibit fatty acid oxidation and reduce NADPH to result in ROS-mediated leukemia cell apoptosis. This highlights a novel AML-therapeutic strategy by which mitochondria are targeted to impair cellular metabolism leading directly to AML cell death. Disclosures No relevant conflicts of interest to declare.

scholarly journals 125I Low Dose Rate Radiation Increases Radiotherapy Sensitivity on Esophageal Cancer Cells via Multiple Mechanisms

2020 ◽  
Author(s):  
Hui Xue ◽  
Lifa Du ◽  
Chunxiao Li ◽  
Hao Wang ◽  
Lixiang Xue ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Flow Cytometry ◽  
Esophageal Cancer ◽  
Single Dose ◽  
Protein Expression ◽  
Dose Rate ◽  
Western Blotting ◽  
Low Dose ◽  
Caspase 3 ◽  
Low Dose Rate

Abstract Objective: To determine the biological effectiveness of iodine 125 (125I) radioactive seeds continuous low dose rate radiation on the human esophageal cancer cell line KYSE150 compare to single dose radiation and explore its potential cellular mechanisms.Method: Three groups of KYSE150 cells were explored: control group, single dose irradiation (SDR) and 125I seeds continuous low dose rate irradiation group (125I-CLDR). Dose-survival curves was obtained by colony formation assay. MTT proliferation assay was used to measure KYSE150 cell vibility. KYSE150 cell apoptosis was analysis by Annexin V-FITC/PI staining, meanwhile, cell cycle analysis was performed by flow cytometry. Bim, Bcl-2, caspase-3 and cleaved caspase-3 protein expression were measured by western blotting to vertify the apoptosis level, as well as CyclinB1 protein expression which values the fuction of G2/M check point.Cell morphology changes were observated under phase contrast microscope. Endoplasmic reticulum stress (ER stress) was measured by GPR78/Bip1 and PERK changes in gene expression, which was detected by Real-time PCR. Reactive oxygen species(ROS) changes and mitochondria were meaured by flow cytometry. ATP detection kit was used to measured ATP level afer two modes of irradiation. DNA-Pks, Ku70 and Ku80 expression were measured by western blotting to represent the damage of DNA damage and repair capabilities. Acridine orange (AO) staining was used to detect level of autophagy and quantitative was measured by flow cytometry. LC3-II, ATG5, Beclin1, p-Akt, p-mTOR, mTOR and p-S6 proteins expression were detectd by western blotting.Results: KYSE150 cells were more radiosensitive to 125I-CLDR than SDR. Two modes of irradiation could both inhibit the proliferation vability of KYSE150 cells, while the inhibition effects in 125I-CLDR was significantly stronger compared with SDR. Compared with SDR, 125I-CLDR showed more proportions of the early and late apoptosis rate as well as cells at G2/M phase. Apoptosis related proteins, such as Bim, caspase-3 and cleaved caspase-3, were elevated, while CyclinB1 expression was decreased in 125I-CLDR group. Cells became bigger and grainy in 125I-CLDR group, meanwhile, ROS levels and ER stress signal was elevated except ATP concentration. Cells stained by AO was anaysised by flow cytometry, results showed that red: green ratio in 125I-CLDR group increased as well as LC3 and ATG5 protein expression detected by western blotting. p-Akt, p-mTOR and p-S6 protein expression were decreased to some extent in 125I-CLDR group cells, while total mTOR protein showed no significant changes.Conclusion: Our results confirmed that 125I-CLDR could strong inhibite KYSE150 cancer cells. Furthermore, we revealed that cell cycle arrest and apoptosis were not the only fate after 125I-CLDR, autophagy might be another important choice which mTOR pathway might be involed in. These findings can support the application of esophageal stent loaded with 125I seeds in clinic.

Sign in / Sign up

Export Citation Format

Share Document