Selective leukemia cell death by activation of the double-stranded RNA-dependent protein kinase PKR.

Deregulated activity of the BCR-ABL tyrosine kinase encoded by the Bcr-Abl oncogene represents an important therapeutic target for all the chronic myelogenous leukemia (CML) phases. In this study, we sought to identify targeted PKR activation by Bcr-Abl AS RNA, an anti-sense RNA complementary to the unique mRNA fragments flanking the fusion point of Bcr-Abl, which can be used as an effective anti-leukemia strategy in K562 cells. Moreover, we observed expression of Bcr-Abl AS RNA in K562 cells which resulted in selective apoptosis induction through specific activation of PKR, leading to phosphorylation of eIF2α, global inhibition of protein synthesis, caspase-8 activation and BAX up-regulation. The targeted PKR activation and induced apoptosis were reversed by the PKR inhibitor 2-aminopurine. Taken together, our results indicate that targeted PKR activation led to selective apoptosis induction in K562 cells, which correlated with caspase-8 activity and enhanced expression of BAX.

Growth of chronic myeloid leukemia cells is inhibited by infection with Ad-SH2-HA adenovirus that disrupts Grb2-Bcr-Abl complexes.

The persistence of Bcr-Abl-positive cells in patients on imatinib therapy indicates that inhibition of the Bcr-Abl kinase activity alone might not be sufficient to eradicate the leukemia cells. Many downstream effectors of Bcr-Abl have been described, including activation of both the Grb2-SoS-Ras-MAPK and Grb2-Gab2-PI3K-Akt pathways. The Bcr-Abl-Grb2 interaction, which is mediated by the direct interaction of the Grb2 SH2 domain with the phospho-Bcr-Abl Y177, is required for activation of these signaling pathways. Therefore, disrupting their interaction represents a potential therapeutic strategy for inhibiting the oncogenic downstream signals of Bcr-Abl. Adenovirus Ad-SH2-HA expressing the Grb2 SH2 domain was constructed and applied in this study. As expected, Ad-SH2-HA efficiently infected CML cells and functioned by binding to the phospho-Bcr-Abl Y177 site, competitively disrupting the Grb2 SH2-phospho-Bcr-Abl Y177 complex. They induced potent anti-proliferation and apoptosis-inducing effects in CML cell lines. Moreover, the Ras, MAPK and Akt activities were significantly reduced in the Ad-SH2-HA treated cells. These were not observed with the point-mutated control adenovirus Ad-Sm-HA with abolished phospho-Bcr-Abl Y177 binding sites. These data indicate that, in addition to the direct targeting of Bcr-Abl, selective inhibition of its downstream signaling pathways may be a therapeutic option for CML, and the Ad-SH2-HA-mediated killing strategy could be explored as a promising anti-leukemia agent in CML.

The intracellular stability of DLC1 is regulated by the 26S proteasome in human hepatocellular carcinoma cell line Hep3B.

Deleted in liver cancer 1 (DLC1), a tumor suppressor gene identified in a primary human hepatocellular carcinoma, encodes a Rho GTPase-activating protein (RhoGAP). Although DLC1 expression has been studied at the transcriptional level, little is known about its regulation at the protein level. Here we show that DLC1 is an unstable protein that is degraded by the 26S proteasome in human hepatocellular carcinoma Hep3B cells. In addition, five putative PEST motifs were identified in the N-terminus of DLC1. Unexpectedly, the N-terminus of DLC1 appeared to be stable. Furthermore, deletion of any one of the five PEST motifs except PEST2 decreased the stability of the N-terminus of DLC1, which suggests that the PEST motifs may play an unrevealed role in maintaining the stability of DLC1. These data indicated that the intracellular stability of DLC1 is regulated by the 26S proteasome via its PEST motifs.

Per2 inhibits k562 leukemia cell growth in vitro and in vivo through cell cycle arrest and apoptosis induction.

Per2 regulates other molecular and biochemical processes beyond their established role in the regulation of the mammalian circadian clock, herein we investigated the growth inhibiting potential of Per2 in human K562 leukemia cells and the underlying mechanisms. The results showed that over-expression of Per2 induced not only cell cycle arrest at G2/M phase but also an increase in apoptosis, which was confirmed by characteristic morphological changes, FCM and evident DNA fragmentation. Further experiments confirmed both up-regulation of P53 and down-regulation of CylinB1and C-myc. On the other hand, while P53 was found to be down-regulated. CylinB1 and C-myc were up-regulated. after Per2 knockdown. In leukemia mice, Per2 transfection was shown to suppress cellular proliferation and accelerate apoptosis of K562 cells. Moreover, fewer leukemia cells were found to have infiltrated into the livers and spleens of the mice from the Per2 transfected group as compared with those from the control group. In summary, Per2 displayed a significant anti-tumor effect through cell cycle arrest and apoptosis induction in K562 cells. These data further support the emerging role of the circadian clock in critical aspects of cancer development and thorough research is underway on the mechanism of Per2 in the leukemia.

[Effect of wild-type p53 gene on the number and proteins of centrosome in leukemic K562 cells].

OBJECTIVE: To observe the effect of recombinant adenovirus-mediated wild-type p53 gene on the number and proteins of centrosome in K562 cells. To explore the possibility of application of wild-type p53 gene therapy in the treatment of chronic myeloid leukemia. METHODS: The recombinant adenoviruses carrying wild-type p53 gene (Ad5 wtp53), mutant p53 gene (Ad5 mtp53) or the green fluorescent protein (GFP) gene was repeatedly amplified and co-infected into K562 cells with cation polybrene. The optimal infection titer and infection time of the recombinant adenoviruses were determined by MTT assay, p53 mRNA and protein expression were determined by RT-PCR and Western blot respectively. The centrosomal structural protein gamma-tubulin and the spindle protein alpha-tubulin were marked simultaneously by indirect immunofluorescence staining, and the expression of the centrosomal gamma-tubulin protein, the mitosis and the number of centrosome were observed under the laser confocal microscopy. RESULTS: Infection efficiency with recombinant adenoviruses was facilitated by polybrene in K562 cells, and 4 microg/ml polybrene was chosen. The optimal adenovirus infection titer was 20,000 MOI and the optimal infection time was 72 hours. p53 mRNA and P53 protein can be expressed in K562 cells by Ad5wtp53 and Ad5mtp53. Both the expression of the centrosomal gamma-tubulin protein and the number of centrosomes were decreased after Ad5wtp53 infection. CONCLUSION: There is sustained expression of P53 protein in K562 cells after its infection by Ad5wtp53. Wild-type P53 protein can lead to the down-regulation of the number of centrosomes and the expression of centrosomal gamma-tubulin protein in K562 cells.

Cloning, expression, purification, distribution and kinetics characterization of the bacterial beta-galactosidase fused to the cytoplasmic transduction peptide in vitro and in vivo.

Cytoplasmic transduction peptide (CTP) offers exciting therapeutic opportunities for the treatment of many diseases caused by cytoplasmic functional molecules. It can transduce large, biologically active proteins into the cytoplasmic compartment of several mammalian cells. However, other intriguing features of CTP, including its activity in vitro, and distribution and tissue infiltration abilities in vivo, remain to be explored. The present study was initiated to (1) further confirm the cytoplasmic localization preference and the enzymatic activity of the transduced CTP-beta-gal in vitro and (2) examine the kinetics and tissue distribution of the CTP-beta-gal fusion protein in mice. A CTP-beta-gal fusion protein was expressed in Escherichia coli and either transduced into BaF3-BCR/ABL cells or administered intravenously into female Balb/C mice at a dose of 100 microg per mouse. Its localization in BaF3-BCR/ABL cells was evaluated by immunocytochemistry and in situ X-gal staining, and its distribution in various tissues was analyzed both by in situ X-gal staining and quantitative enzymatic activity assay. beta-Galactosidase enzyme activity was observed in BaF3-BCR/ABL cells and in all tissues tested, with peak activity occurring at 15 min in most tissues and at 24h in brain. These data will not only allow rational selection of delivery schedules for therapeutic CTP, but will also aid the use of CTP fusion protein transduction in the development of protein therapeutics targeting the cytoplasmic compartment both in vitro and in vivo.

Inhibitory effect of wild-type p53 gene on excessive replication of centrosomes in leukemia cell line K562.

BACKGROUND AND OBJECTIVE: Mutation and deletion of the p53 gene in tumor cells is one of the major reasons for aneuploid development and genomic instability. Abnormal centrosomes exist in chronic myelogenous leukemia patients at different stages; furthermore, the degree of abnormality is associated with the clinical stage and more severe in the blast crisis stage. This study was to establish the leukemia cell line K562 with the exogenous wild-type p53 (wt-p53) gene, and to explore the effect of the p53 gene on centrosomes in K562 cells. METHODS: The recombinant adenoviruses carrying the wt-p53 gene (Ad5wtp53), the mutant p53 gene (Ad5mtp53) and the green fluorescent protein gene (Ad5GFP) were amplified respectively in HEK293 cells, and co-infected with cation polybrene into K562 cells respectively; uninfected K562 cells were used as blank control. The infection efficiency was analyzed by flow cytometry. P53 expression was detected by Western blot. Centrosomes were counted under the laser confocal microscope after indirect immunofluorescence staining. The expression of Gadd45a (growth arrest and DNA damage), BubR1 (Bub 1 related) and Aurora A was detected by western blot. RESULTS: K562 cell line with exogenous wt-p53 gene was established. The infection efficiencies of three groups were over 60%, and P53 sustained expression for 72 h. The percentage of cells with amplified centrosomes (more than 2/cell) in Ad5wtp53 group was decreased to (0.38 +/- 0.02)%, lower than that of blank control group (p < 0.05). Meanwhile, the protein levels of Gadd45a and BubR1 in Ad5wtp53 group were upregulated by 93% and 88% of blank control (p < 0.05), respectively, and the protein level of Aurora A was downregulated by 56% of blank control (p < 0.05). CONCLUSIONS: P53 protein is sustained to express in K562 cells after being infected by Ad5wtp53. wt-p53 can suppress excessive replication of centrosomes that may contribute to the upregulation of Gadd45a and BubR1 protein expression as well as the downregulation of Aurora A protein expression.

Cloning, expression, purification and functional characterization of the oligomerization domain of Bcr-Abl oncoprotein fused to the cytoplasmic transduction peptide.

Protein-based cellular therapeutics have been limited by getting molecules into cells and the fact that many proteins require accurate cellular localization for function. Cytoplasmic transduction peptide (CTP) is a newly designed transduction peptide that carries molecules across the cell membrane with a preference to localize in the cytoplasmic compartment and is, therefore, applicable for cytoplasmic targeting. The Bcr-Abl fusion protein, playing major causative role in chronic myeloid leukemia (CML), is a cytoplasmic oncoprotein that contains an N-terminus oligomerization domain (OD) mediating homodimerization of Bcr-Abl proteins, and an intact OD in Bcr-Abl is required both for the activation of its transforming activity and tyrosine kinase. Therefore, disrupting Bcr-Abl oligomerization represents a potential therapeutic strategy for inhibiting Bcr-Abl oncogenicity. In this study, we explored the possible homodimerization-disrupting and tyrosine kinase inhibiting effect of the transduction of OD in Bcr-Abl positive K562 cells. By expressing in Escherichia coli a CTP-OD-HA fusion protein followed by Ni+-NTA affinity purification, immunoblot identification and enterokinase cleavage, we showed that the CTP-OD-HA protein was structurally and functionally active in that it potently transduced and primarily localized into the cytoplasmic compartment, heterodimerized with Bcr-Abl, and potently inhibited the phospho-tyrosine pathways of Bcr-Abl oncoprotein at a low concentration of 4 microM. These results delineate strategies for the expression and purification of therapeutic molecules for intracytoplasmic protein based therapeutics and the CTP-OD-HA-mediated killing strategy could be explored as a promising anti-leukemia agent or an adjuvant to the conventional therapeutic modalities in chronic myeloid leukemia, such as in vitro purging.

[Targeted blockage of RNA binding protein E2 by decoy RNA induces the granulocytic differentiation of K562 cells].

OBJECTIVE: To use a decoy RNA targeted blockage of the RNA binding protein E2 (hnRNP E2) resulting in the CCAAT/enhancer-binding protein alpha (C/EBP alpha) gene's abnormal translation and investigate its effect on the granulocytic differentiation of K562 cells and the probable molecular mechanism. METHODS: The hnRNP E2 decoy RNA expression plasmid was constructed and transfected into K562 cells with cationic liposome, and stable expression cells were obtained by G418 selection. The changes of C/EBP alpha and granulocyte colony-stimulating factor receptor (G-CSFR) gene expression were detected by RT-PCR and Western blot. The morphologic changes were observed after Wright-Giemsa staining. The expression of granulocytic differentiation antigens CD13 and CD15 was studied by immunocytochemistry. RESULTS: The stably expressed pG cells were obtained. Its C/EBP alpha mRNA level remained unchanged, while 42kD-C/EBP alpha protein expression was increased by (49.7 +/- 5.5)% (P < 0.05); and G-CSFR mRNA was increased by (42.1 +/- 3.6)% (P < .05), and its protein was increased by (37.4 +/- 6.2)% (P < 0.05) compared to that in the K562 control cells. The characteristics of polymorphonuclear neutrophils appeared in pG cells and CD13 and CD15 positive cell ratios were (18.7 +/- 2.5)% and (26.3 +/- 2.9)% respectively. CONCLUSIONS: HnRNP E2 decoy RNA can induce granulocytic differentiation of K562 cells, and G-CSF promotes this effect. The mechanisms may be that decoy RNA specifically blocks hnRNP E2, hence regulates the translation of C/ EBP alpha mRNA, restores the expression of 42kD-C/EBP alpha, and then up-regulates the expression of G-CSFR gene.

[Effect of targeted activation of protein kinase PKR on proliferation of leukemia cell line K562 and its mechanism].

BACKGROUND & OBJECTIVE: The bcr-abl fusion gene induced by reciprocal translocation of t(9; 22)(q34; q11) plays an important role in pathogenesis of chronic myeloid leukemia (CML). Using the strategy of activating double-stranded RNA (dsRNA)-dependent protein kinase (PKR) by the dsRNA formed between the CML-specific bcr/abl fusion gene mRNA and the exogenous recombinant antisense RNA, this study was to investigate the effect of the activated PKR on the proliferation of leukemia cell line K562, and explore its possible mechanisms. METHODS: dsRNA analogue polyriboinosinic polyribocytidylic acid (PolyIC), retroviral vector containing 40 bp of bcr/abl fusion gene sequence (RV-40AS), RV-40AS and 2-aminopurine (2-AP), and retroviral vector containing green fluorescent protein sequence (RV-GFP) were transfected or infected into K562 cells respectively; ECV304 cells were used as control. Cell proliferation was determined by cell counting, MTT assay, and semisolid clone formation experiment. Cell cycle was analyzed by flow cytometry (FCM). The expression of PKR, phosphated PKR (p-PKR), eukaryotic initiation factor-2alpha (eIF2alpha), and phosphated eIF2alpha (p-eIF2alpha) was detected by Western blot. Total protein synthesis was studied by 3H-leucine incorporation. RESULTS: polyIC inhibited the proliferation of K562 cells and ECV304 cells unspecifically, while RV-40AS only inhibited the proliferation of K562 cells specifically. 2-AP blocked the inhibitory effect of RV-40AS on the proliferation of K562 cells. The S phase proportion was significantly lower in polyIC-and RV-40AS-treated K562 cells than in untreated cells [(37.26+/-2.35)% and (31.48+/-3.65)% vs. (58.53+/-5.42)%, P<0.05], while the G0/G1 phase proportion was significantly higher in polyIC-and RV-40AS-treated cells than in untreated cells [(50.97+/-2.18)% and (57.47+/-3.61)% vs. (36.44+/-4.20)%, P<0.05]. The expression of p-PKR and p-eIF2alpha in polyIC-and RV-40AS-treated K562 cells and polyIC-treated ECV304 cells was obviously up-regulated. The total protein synthesis level was significantly lower in RV-40AS-treated K562 cells than in untreated K562 cells [(3.5+/-1.9) cpm/ng vs. (26.8+/-2.6) cpm/ng, P<0.05]. CONCLUSION: Targeted activation of PKR could inhibit the proliferation of K562 cells through inhibiting protein synthesis, and arresting progression of cell cycle.

[Effect and possible mechanism of HnRNP E2 decoy RNA on proliferation of K562 leukemia cells].

BACKGROUND & OBJECTIVE: The abnormal expression of poly(rC)-binding protein E2 (hnRNP E2) induced by BCR/ABL plays an important role in blast crisis of chronic myeloid leukemia (CML). The present study was to investigate the effect of hnRNP E2 decoy RNA on the cell proliferation in K562 leukemia cells, and further elucidate the possible underlying mechanisms. METHODS: Decoy hnRNP E2 plasmid was constructed and transfected into K562 cells using cationic liposome. Stably transfected cells were selected with G418. The cell proliferation rate was determined by cell growth curve using trypan blue staining, and the cell cycle was analyzed by flow cytometry. The changes of CCAAT/enhancer-binding protein alpha (C/EBP alpha) and c-Myc gene expression were detected by reverse transcription polymerase chain reaction (RT-PCR) and Western blot. RESULTS: The proliferation rate of stably transfected K562 cells was inhibited by (62.73+/-12.92)%. The cell cycle was arrested at S phase [stably transfected K562 cell group: (55.59+/-4.67)%, control group: (44.70+/-4.21)%, P<0.05]; C/EBPalpha mRNA level remained unchanged. However the 42 ku-C/EBPalpha protein expression was elevated by (49.72+/-5.58)%; c-Myc mRNA and protein expression was inhibited by (58.27+/-7.23)% and (57.26+/-6.52)%, respectively. CONCLUSION: HnRNP E2 decoy RNA could inhibit the proliferation of K562 cells, and this may be caused by the blockage of the binding between hnRNP E2 and C/EBPalpha mRNA and subsequent elevation of 42 ku-C/EBPalpha by decoy RNA.

[Regulatory effect of STAT5 decoy oligonucleotides on trans-activation of bcl-x gene promoter in K562 cells].

BACKGROUND & OBJECTIVE: Constitutive activation of signal transducers and activators of transcription 5 (STAT5) plays an important role in malignant transformation of chronic myeloid leukemia (CML) cells. This study was to explore regulatory effect of STAT5 decoy oligonucleotides (ODNs) on trans-activation of its downstream target bcl-x gene in K562 cells. METHODS: STAT5 decoy ODNs, mismatched ODNs (M-ODNs), and FAM-decoy ODNs were designed and synthesized. FAM-decoy ODNs were used as control, and transfected into K562 cells by cationic liposomes, analyzed by flow cytometry (FCM) and fluorescent inversive microscopy. The bcl-x promoter fragment acquired by polymerase chain reaction (PCR) was inserted into pGL3-basic to construct luciferase report plasmid pGL3b-bclxp, which was co-transfected with decoy ODNs or M-ODNs into K562 cells. The activity of luciferase was detected. After transfection of decoy ODNs, and M-ODNs, expression of bcl-xL mRNA in K562 cells was detected by reverse transcription-PCR (RT-PCR),cell apoptosis was detected by FCM. RESULTS: FAM-decoy ODNs were incorporated into K562 cells in a dose-dependent manner. The incorporation efficiency reached 99.1% at the concentration of 4 micromol/L 24 h after transfection, and green fluorescence could be observed in cells under fluorescent inversive microscope. The luciferase activity was significantly lower in STAT5 decoy ODNs group than in control group [(181.48+/-204.46) RLU/microg protein vs. (675.26+/-62.91) RLU/mug protein, P < 0.05], but that of M-ODNs group [(632.07+/-98.95) RLU/microg protein] has no significant difference with that of control group (P > 0.05). mRNA level of bcl-xL was decreased by STAT5 decoy ODNs, but not by M-ODNs. Moreover, Sub G1 peak was detected in STAT5 decoy ODNs group by FCM. CONCLUSION: Transfection of STAT5 decoy ODNs can down-regulate the trans-activation of bcl-x in K562 cells.

[VEGF antisense oligonucleotide inhibits the expression of vascular endothelial growth factor in human leukemic cell lines].

OBJECTIVE: To explore the effects of vascular endothelial growth factor (VEGF) antisense phosphorothioated oligodeoxynucleotide (AS-ODN) on the expression of VEGF in human leukemic cell lines (HL-60 and K562 cells). METHODS: The levels of VEGF mRNA and protein in leukemic cells incubated with VEGF AS-ODN were measured by RT-PCR, immunohistochemistry assay and ELISA. MTT test was used to examine the influence of the culture supernatant (CS) of VEGF AS-ODN treated leukemic cells on the proliferation of human umbilical vein endothelial cells (ECV304). RESULTS: After leukemic cells were treated with different concentrations (2.5 approximately 15.0 micro mol/L) of VEGF AS-ODN for 24 h, VEGF mRNA level in the cells decreased remarkably in a concentration dependent manner, no change was found in the VEGF missense ODN treated cells (MS-ODN). When the leukemic cells were treated with 5 micro mol/L VEGF AS-ODN for 24 h, VEGF protein level decreased greatly both in the cells and in the CS; and the proliferation stimulating effect of the treated CS on the ECV304 cells reduced. Meanwhile, there was no obvious change in VEGF protein and its effect in the VEGF MS-ODN treated group. CONCLUSION: VEGF AS-ODN could inhibit VEGF expression in human leukemic cell lines in vitro.

[Targeted blockage of STAT5 by a decoy oligodeoxynucleotide inhibits the growth and proliferation of K562 cells].

OBJECTIVES: To investigate targeted blockage of BCR/ABL oncoprotein mediated cell transformation by STAT5 decoy oligodeoxynucleotide (ODN), its effect on the growth and proliferation inhibition of K562 cells and the related molecular mechanisms. METHODS: STAT5 decoy ODN, designed and synthesized in vitro, was transfected into K562 cells by cationic lipid. The cell growth curve and colony formation assay were used to reflect the growth and proliferation capacity of K562 cells, RT-PCR to detect the expression of three genes downstream STAT5. RESULTS: Confocal microscopy demonstrated that STAT5 decoy ODN was successfully transfected into K562 cells (95.2% positive cells). STAT5 decoy ODN inhibited the growth of K562 cells (inhibition rate 77.7%) and their colony formation capacity (Decoy ODN treated group 8.3% vs control group 35.7%, P < 0.05) after the treatment with STAT5 decoy ODN, the expressions of c-myc, bcl-X(L), cyclin D1 mRNA were down-regulated by 15.4%, 30.8%, 29.1%, respectively in the K562 cells. CONCLUSIONS: STAT5 decoy ODN inhibits the growth and proliferation of K562 cells. The mechanisms may be that decoy ODN blocks the transcriptional activation potent of STAT5 and down-regulates the expression of these tumor related genes downstream STAT5.

[Effect of Skp2 antisense oligodeoxynucleotide on growth and proliferation of K562 cells].

BACKGROUND & OBJECTIVE: The ubiquitin-proteosome pathway is important for selective degradation of short-lived protein in eukaryotic cells. In this pathway Skp2 (S-phase kinase-associated protein 2) plays a critical role in degrading cyclin-dependent kinase inhibitor p27. It is verified that Skp2 is an oncoprotein that promotes cell cycle progression in solid tumor, but its role in leukemia cells remains unclear. This study was designed to investigate the effect of Skp2 antisense oligodeoxynucleotides(ASODN) on the growth and proliferation of leukemic K562 cells and its probable mechanism. METHODS: K562 cells were cocultured with Skp2 ASODN. The growth and proliferation of K562 cells were observed with light microscopy and MTT assay. The cell cycle was analyzed using flow cytometry. The expression levels of mRNA and protein were determined using reverse transcription-polymerase chain reaction (RT-PCR) and immunocytochemistry, respectively. RESULTS: After treatment with Skp2 ASODN, the growth and proliferation of K562 cells were inhibited and the cell cycle was arrested at G(0)/G(1) phase(Skp2 ASODN group 39.7+/-9.1% vs. control group 31.5+/-7.3%,P< 0.05). Both Skp2 mRNA and its protein levels were down-regulated. Although p27 mRNA level remained unchanged, its protein level was up-regulated. CONCLUSION: Skp2 ASODN can inhibit the growth and proliferation of K562 cells, which is mediated by interfering with ubiquitin-proteosome system and regulating of cell cycle progression.

[Study on the transcriptional activation of MTS1 gene beta promoter].

OBJECTIVE: To 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. METHODS: Seven 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. RESULTS: Seven 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. CONCLUSION: MTS1 gene beta promoter can be activated in Jurkat cell line.