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*

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

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

OBJECTIVETo investigate the effect and possible mechanism of bromo-domain inhibitors (JQ1) on proliferation inhibition and inducing apoptosis of acute T lymphocyte leukemia cell line (Jurkat) .

METHODSJurkat cell line was treated by JQ1 at different concentrations. MTT was used to detect the cell proliferation inhibition rate. The flow cytometry with AnnexinV-FITC/PI fluorescence staining was used to detect the changes of apoptosis rate, and real-time fluorescent quantitative PCR was used to detect c-Myc/Notch1 gene expression levels.

RESULTSWith the increasing of drug concentration and prolonging of time, the inhibitory rate of Jurkat cell growth was enhanced in time-dose dependent manner; Jurkat cells was treated by 0.8, 1.6, and 4 µ mol/LJQ1 for 48 h and 72 h, the cell apoptosis rate was enhanced with the increase of drug concentration and prolonging of time, and the difference was statistically different in comparison with the control group(P<0.05); PCR detection indicated that Notch1 and c-Myc mRNA expression was reduced in 48 h after JQ1 treatment, which was statistically different from the control group,(P<0.05) .

CONCLUSIONJQ1 can effectively inhibit the growth of Jurkat cell line, and potentially induce apoptosis through Notch1 and c-Myc gene. Hence JQ1 may be one of new methods used to treat T-ALL.

Apoptosis ; Azepines ; Cell Proliferation ; Flow Cytometry ; Genes, myc ; Humans ; Jurkat Cells ; Nuclear Proteins ; Transcription Factors ; Triazoles

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

OBJECTIVETo investigate the effect of MTS1 gene beta promoter transcriptional activation in T-cell acute lymphoblastic leukemia (T-ALL) cell lines and identify the fragment with transcriptional activation.

METHODSSeven pGL3 recombinant plasmids with the same 3'-end transcriptional start site but the different 5'sequences were constructed by gene recombinant technique and transfected into Jurkat cell line which is biallelic deletion of MTS1 gene by transient transfection. Luciferase report gene was detected to observe beta promoter transcriptional activation.

RESULTSSeven pGL3 recombinant plasmids containing different fragments of beta promoter were obtained, all of them showed transcriptional activation in Jurkat cell line. Among them, the 0.38 kb fragment cut by SacII-SacI is fundamental in transcription.

CONCLUSIONMTS1 gene beta promoter can be activated in Jurkat cell line.

Genes, p16 ; Humans ; Jurkat Cells ; Plasmids ; genetics ; Promoter Regions, Genetic ; genetics ; Transcriptional Activation ; 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

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

HCAP1 is a novel hepatic cancer related gene located on human chromosome 17p13.3. The loss of heterozygosity occurred at 17p13.3 in various human cancers. In order to investigate the effects of exogenous HCAP1 gene products on cell proliferation of T lymphoma Jurkat cell line, HCAP1 gene! was transfected into Jurkat cells mediated by liposome, and the cells stably expressing exogenous HCAP1 were screened with G418. The effects of HCAP1 products on cell proliferation were assessed by viable cell count, cell growth curve and colony formation assay in soft agar. The results showed that the HCAP1 transgenic Jurkat cells displayed slow growth rate, extended doubling time and reduced colony formation capability, as compared with the cells transfected with pBK/CMV empty vector (P < 0.01). It is concluded that exogenous HCAP1 gene products could inhibit the proliferation of Jurkat cells.
Carcinoma, Hepatocellular ; genetics ; Cell Division ; Humans ; Jurkat Cells ; Liver Neoplasms ; genetics ; Neoplasm Proteins ; genetics ; Peptides ; Transfection