No abstract available.
Actinobacillus* ; Aggregatibacter actinomycetemcomitans* ; Apoptosis* ; Humans ; Jurkat Cells*

PURPOSE: FK506 (Tacrolimus) has been widely used as an immunosuppressant. We examined the effects of FK506 on the activation, proliferation and expression of cytotoxic effector molecules of Jurkat human T-lymphocytes. METHODS: We investigated the effects of this compound on cell viability, the production of reactive oxygen species and mitochondrial dysfunction. The cells were cultured in the presence or absence of FK506. Flow cytometric analysis was performed after staining with PI. The viability of the Jurkat cells was decreased by the addition of FK506 in a dose-and time-dependent manners. RESULTS: FK506-induced cytotoxicity was characterized by G0/G1 phase cell-cycle arrest. FK506 induced cell death was confirmed by the caspase-3 protease activation. In addition, the pharmacologic scavenging study of reactive oxygen species (ROS), including H2O2, revealed that cytotoxicity was achieved by the generation of ROS, which might modulate the mitochondrial dysfunction. CONCLUSION: These results suggest that FK506 functions in CDK4-cyclin D1 mediated cell-cycle arrest of Jurkat cells via generation of ROS and mitochondrial dysfunction.
Caspase 3 ; Cell Death ; Cell Survival ; Humans* ; Jurkat Cells ; Reactive Oxygen Species ; T-Lymphocytes* ; Tacrolimus*

OBJECTIVE: To investigate the effect of β-arrestin1 gene on senescence of T-ALL cells and its possible mechanism. METHODS: The bone marrow specimens of T-ALL patients and controls were collected, the expression of β-arrestin1 and β-arrestin1 in the T-ALL patients was detected by RT-PCR and Western blot, respectively, and the relation of β-arrestin1 expression with the clinical pathologic characteristics and the prognosis of T-ALL patients was analyzed statistically. The stable Jurkat cell line with knocked down or overexpressed β-arrestin1 was constructed, the CCK method was used to detect the Jurkat cell number, the β-gal staining was used to analyze the effect of β-arrestin1 on senescence of Jurkat cells, the cross analysis of RNA-Seg data and KEGG data was performed for screening the possible signaling pathway, and Western blot was performed for varifying the key sites of signaling pathway. RESULTS: The β-arrestin1 expression in specimens of T-ALL patients decreased (P＜0.01), moreover the β-arrestin1 expression negatively related with peripheral blood cell number (r=-0.601), the blasts in peripheral blood (r=-0.516) and extramedullary infiltration (r=-0.359), while positively related with the response to chemotherapy (r=0.393). The detection of stable Jurkat cell line with knocked-down and overexpressed β-arrestin1 found that the β-arrestin 1 could decrease the Jurkat cell number and accelarate the senescence of Jurkat cells (P＜0.05). The cross analysis of RNA-Seg data and KEGG data showed that the senescence of T-ALL cells may be regulated via RAS-P16-PRb-E2F1 by β-arrestin 1. Western bolt confirmed that β-arrestin1 promoted the expression of Ras and p16, and decreased the expression of pRB and E2F1 (P＜0.05). CONCLUSIONS β-arrestin1 accelerates the senescence of Jurkat cells via Ras-p16-pRb-E2F1, and delays the progression in T-ALL, which may provide a new hypothesis for the pathogenesis of T-ALL.
Cellular Senescence ; Humans ; Jurkat Cells ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; Prognosis ; beta-Arrestin 1 ; genetics

OBJECTIVE: To investigate the apoptosis-inducing effect of Ginsenoside (Rh2) on human acute T lymphoblastic leukemia Jurkat cells and it mechamism. METHODS: The effects of different concentration of Rh2 (0, 10 , 20, 40 and 80 µg/ml) on the proliferation activity of Jurkat cells were detected by methyl thiazolyl tetrazolium (MTT) method, and the semi-inhibitory concentration (IC) of Rh2 on Jurkat cells at 48 h was calculated. Microscopy and Hoechst 33258 fluorescence staining were used to observe the apoptosis of Jurkat cells treated with IC Rh2 for 48 h. And then, the cell experiment was divided into 4 groups: control, Rh2 (IC), PI3K inhibitor LY294002 (50 µmol/l) and Rh2 (IC) + LY294002 (50 µmol/l). After synchronous culture for 48 h, the apoptosis and cycle changes of Jurkat cells were detected by using PI single staining and Annexin V-FITC/PI double staining, respectively. Western blot was used to detect the expression level of apoptosis-related protein BAX, BCL-2, Cleaved-Caspasase 3, cell cycle-related protein Cyclin D1 and PI3K/AKT signaling pathway-related protein AKT and p-AKT. RESULTS: Rh2 (10-80 µg/ml) inhibited the Jurkat cell proliferation in a dose-time dependent manner (r = 0.999, P＜0.01; r = 0.991; P＞0.05), accompanied by obvious morphological changes of apoptosis cells. Flow cytometry showed that compared with the control group, the cell apoptosis rate in Rh2 or LY294002 group significantly increased, and the cell cycle was mostly blocked in G0/G1 phase. However, the cell apoptosis and cell cycle block in Rh2+LY294002 group were more significant than that in Rh2 and LY294002 group. Western blot showed that compared with the control group, Rh2 significantly promoted the expression of BAX and Cleaved-Caspasase 3, inhibited the expression of BCL-2, Cyclin D1 and p-AKT, furthermore LY294002 significantly promoted this effect. CONCLUSION Rh2 can induce the apoptosis of Jurkat cells in time-dose dependent manner, moreover, Rh2 also can result in an obvious block of Jurkat cells at G0/G1, that may be closely related to a series of apoptotic signaling cascades mediated by Rh2 inhibiting PI3K/AKT pathway.
Apoptosis ; Cell Proliferation ; Ginsenosides ; Humans ; Jurkat Cells ; Phosphatidylinositol 3-Kinases ; Precursor Cell Lymphoblastic Leukemia-Lymphoma

OBJECTIVE: To investigate the effects of dihydroartemisinin (DHA) on the proliferation and apoptosis of human T-cell acute lymphoblastic leukemia (T-ALL) Jurkat cell. METHODS: The effects of DHA on the proliferation of Jurkat cells and the recovery of DHA-inhibited cell viability by N-acetyl-L-cysteine (NAC) were examined by CCK-8 assay. Flow cytometry was performed to analyze the cell apoptosis and generation of reactive oxygen species (ROS). Western-blot was used to detected protein expression of DNA damage-related genes, as well as apoptosis-associated genes, respectively. RESULTS: DHA inhibited the proliferation of Jurkat cells, and shows a concentration-dependent manner(r =0.936), and NAC could partially restore the activity of DHA on cell proliferation inhibition. With the increase of drug concentration, the apoptosis rate (r =0.946) and ROS accumulation was increased (r =0.965). Western blot showed that the protein expressions of DNA damage-related gene γ-H2AX and apoptosis-related genes p53, c-Caspase3, BAX and cPARP were significantly increased, and BCL-2 protein expression was decreased. CONCLUSION DHA can induce ROS production in Jurkat cells, which can cause DNA damage, activate the P53 apoptotic pathway, and promote apoptosis of cells.
Apoptosis ; Artemisinins ; Humans ; Jurkat Cells ; Oxidative Stress ; Precursor T-Cell Lymphoblastic Leukemia-Lymphoma ; Reactive Oxygen Species

This study was aimed to construct miRNA sponge targeting miR-20a and to establish a stable cell line Jurkat-S, paving the way for further research on function of miR-20a and application of RNAi in gene therapy. One pair of two-repeated oligonucleotide sequences containing bulged sites that are mispaired opposite miR-20a positions 9-12 was designed and synthesized with enzyme cutting sites. The annealed oligonucleotide fragments were subcloned into pCDNA3.0-L expressing vector. After double-enzyme cutting, the vector was ligated to the annealed oligonucleotide fragments again. Enzyme cutting and luciferase activity assay were performed for identification after four repeats. Then the ligated fragment was subcloned to lentivirus expressing vector. Virus particles were collected after the control or sponge vectors were co-transfected with the psPAX2 packaging plasmid and the envelope plasmid pMD2.G into HEK-293T cells using Lipofectamine 2000. The Jurkat cells were transfused with recombinant lentivirus-transfusing units plus 6 µg/ml of Polybrene. Real-time PCR and Western blot were used to detect the mRNA and protein expression of P21 and E2F1 after lentivirus transfusion respectively. As a result, luciferase activity assay demonstrated that the sponge targeting miR-20a was constructed successfully and the virus was packaged in 293T. The titer of virus was 5×10(7) TU/ml. Stable transfected Jurkat-S cell line was established. As was expected, the mRNA and protein level of P21 and E2F1 was upregulated significantly in Jurkat-S cells. It is concluded that the miR-20a sponge is constructed successfully, and Jurkat-S stable cell line is established, in which the expression of miR-20a is inhibited stably.
Gene Expression ; Genetic Vectors ; Humans ; Jurkat Cells ; MicroRNAs ; genetics ; Plasmids ; RNA, Small Interfering ; genetics ; Transfection

This study was purposed to compare the anti-leukemic effects of E.coli-L-Asp and Erwinia-L-Asp in vitro, and to investigate their mechanism. The cell apoptosis and proliferation inhibition rate were measured by CCK-8 kit, and IC50 of two drugs was calculated by using SPSS software. Pro-apoptosis effect of E.coli-L-Asp and Erwinia-L-Asp on REH and Jurkat cell lines was also determined by flow cytometry with Annexin V/PI double staining. Concentration changes of 4 amino acids (Asn, Aspa, Gln, and Glu) before and after medication were detected by using high pressure liquid chromatography (HPLC) assay. The results showed that both REH and Jurkat cell lines were sensitive to L-Asp drugs from two different strains, and E.coli-L-Asp and Erwinia-L-Asp displayed the inhibition effect on the proliferation of Jurkat and REH cell lines in dose-dependent and time-dependent manners. The inhibition cell of proliferation and cell apoptosis in Erwinia-L-Asp group were higher than those in E.coli-L-Asp group after 24 hours (P < 0.05) . However, after treatment of REN and Jurkat cells with 2 kind of L-Asp for 48 hours, the inhibition of cell proliferation and apoptosis rates were not significantly different between the 2 L-Asp drugs (P > 0.05). The Asn in medium could be depleted by two different L-Asp drugs with low concentration. Both the two L-Asp drugs had the same capability to deplete the Asn surrounding leukemia cells (P > 0.05). The Gln in medium could be depleted by two L-Asp drugs with high concentration. The hydrolysis effect of Erwinia-L-Asp on Gln was stronger than that of E.coli-L-Asp (P < 0.05). It is concluded that in a certain range of concentrations, E.coli-L-Asp and Erwinia-L-Asp exert anti-leukemia effect in dose-dependent manner. Depletion of Gln and Asn in surrounding environment and induction of cell apoptosis are two potential mechanisms, by which leukemia cells can be killed. Erwinia-L-Asp may be chosen as the first-line drug to treat childhood ALL for its fast action and stronger hydrolysis effect on Gln.
Apoptosis ; drug effects ; Asparaginase ; pharmacology ; Cell Proliferation ; drug effects ; Flow Cytometry ; Humans ; Jurkat Cells

The aim of study was to investigate the effect of a traditional Chinese medicine, emodin, on proliferation and apoptosis in T lymphocytic leukemic cell line Jurkat and its mechanisms. Cell proliferation inhibition was detected by MTT assay. Cell apoptosis was measured by DNA ladder and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay. The expressions of related proteins and caspase family members were determined by Western blot. The results showed that emodin inhibited proliferation in Jurkat cells, with an IC50 about 20 micromol/L and induced cell apoptosis in both time-and dose-dependent manners. The expressions of proliferation-related protein C-MYC, hTERT and apoptosis-related protein BCL-2 were down-regulated in a time dependent manner after the treatment with emodin. The expressions of procaspase-3, -8 and -9 all decreased while activated caspase-3 and PARP expressions were up-regulated. It is concluded that emodin can remarkably inhibit cell proliferation and induce apoptosis in Jurkat cells. The down-regulation of proliferation-related proteins C-MYC, hTERT and apoptosis-related protein BCL-2 expressions and activation of caspase cascade may be involved in the process of apoptosis.
Apoptosis ; drug effects ; Caspases ; metabolism ; Cell Proliferation ; drug effects ; Emodin ; metabolism ; pharmacology ; Humans ; Jurkat Cells

Alternations of lymphocyte in biophysical properties (e.g., morphology and viscoelasticity) are related to the human health, disease diagnosis and treatment. Here, we used atomic force microscopy (AFM) to characterize the morphology and mechanical properties of normal lymphocyte and Jurkat. The AFM images revealed that their cell shapes appeared similar. The mechanical properties of the two groups were tracked with AFM-based force spectroscopy. The normal lymphocyte cells had a high adhesion force distribution in (796.7 +/- 248.5) pN, whereas the Jurkat cells had a low force distribution in (158.5 +/- 37.5) pN. The adhesion force revealed that the Young's modulus of normal lymphocyte cells (0.471 kPa +/- 0.081 kPa) was nearly four times higher than that of Jurkat cells (0.0964 kPa +/- 0.0229 kPa) at the same loading rate. The stiffness of normal lymphocyte cells was (2.278 +/- 0.488) mN/m and that of Jurkat cells was (4.322 +/- 0.382) mN/m. The differences in mechanical properties of normal and cancerous cells were obvious that healthy and diseased states could be clearly distinguished. These results may be applied to the clinic disease diagnosis for distinguishing the normal cells from the cancer ones even when they show similar shapes.
Biomechanical Phenomena ; Humans ; Jurkat Cells ; physiology ; ultrastructure ; Lymphocytes ; physiology ; ultrastructure ; Microscopy, Atomic Force ; methods

This study was aimed to explore the effects of oleanolic acid on PTEN expression and apoptosis of Jurkat cells. The inhibitory rate was measured by Cell Counting Kit-8. The apoptotic nucleus morphous was observed by Hoechst 33258 staining. The apoptosis rate of Jurkat cells were determined by flow cytometry with Annexin V/PI double staining. PTEN mRNA and protein were detected by quantitative real-time PCR and Western blot respectively. The results showed that oleanolic acid inhibited the proliferation of Jurkat cells in time- and dose-dependent manners. The 50% growth inhibition (IC(50)) at 12, 24 and 48 hours were about 85.35 µmol/L, 53.66 µmol/L and 33.18 µmol/L respectively. Flow cytometric assay showed that the apoptotic rates of Jurkat cells treated with oleanolic acid (0, 40, 80 and 160 µmol/L) for 24 hours were 6.72%, 19.8%, 28.72% and 30.12% (p < 0.05). PTEN mRNA and protein expressions were up-regulated in Jurkat cells treated with oleanolic acid of concentration 80 µmol/L and 160 µmol/L for 24 hours. It is concluded that up-regulation of PTEN mRNA and PTEN protein may be involved in oleanolic acid-induced Jurkat cell apoptosis.
Apoptosis ; drug effects ; Cell Proliferation ; Humans ; Jurkat Cells ; Oleanolic Acid ; pharmacology ; PTEN Phosphohydrolase ; metabolism ; Up-Regulation