Qing Xiao

Chongqing Medical University, Ch’ung-ch’ing-shih, Chongqing Shi, China

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Publications (19)46.56 Total impact

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    ABSTRACT: SH3 domain plays an important role in maintaining autoinhibition of BCR-ABL protein. RIN1 interacts with BCR-ABL SH3 domain via PxxP motifs to promote autophosphorylation as well as activation of BCR-ABL tyrosine kinase, suggesting using exogenous SH3 domain which blocks the interaction of BCR-ABL and RIN1 could be an adjunct therapy for CML. Here, we reported a novel p-BCR-ABL inhibitor, designed as ABL SH3 mutant, and identified its effects on inhibiting the tyrosine kinase activity of BCR-ABL without or with imatinib (IM) in vitro and in vivo. Our results demonstrated that ABL SH3 mutant T79Y markedly repressed the expression of BCR-ABL signaling pathways in IM-resistant cell lines KCL22 and K562/G01 as well as IM-sensitive cell line K562. Moreover, combination of T79Y with IM considerably decreased the proliferation of leukemia cells in vivo. Inhibition of BCR-ABL and RIN1 interaction using exogenous modified BCR-ABL SH3 domain provides a feasible and alternative option of small molecule inhibitors for CML treatment. Copyright © 2015. Published by Elsevier Ireland Ltd.
    No preview · Article · Aug 2015 · Cancer letters
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    ABSTRACT: Myelodysplastic syndromes (MDS) are a heterogeneous group of myeloid disorders characterized by peripheral blood cytopenias and a high risk of progression to acute myeloid leukaemia (AML). Fucoidan, a complex sulphated polysaccharide isolated from the cell wall of brown seaweeds, has recently attracted attention for its multiple biological activities and its potential as a novel candidate for cancer therapy. In the present study, the anti‑cancer activity of fucoidan was investigated in the MDS/AML cell line SKM‑1. Fucoidan inhibited proliferation, induced apoptosis and caused G1-phase arrest of the cell cycle in SKM‑1 cells as determined by a cell counting kit 8 assay and flow cytometry. Furthermore, reverse transcription quantitative polymerase chain reaction and western blot analyses indicated that treatment with fucoidan (100 µg/ml for 48 h) activated Fas and caspase‑8 in SKM‑1 cells, which are critical for the extrinsic apoptotic pathway; furthermore, caspase‑9 was activated via decreases in phosphoinositide-3 kinase/Akt signaling as indicated by reduced levels of phosphorylated Akt, suggesting the involvement of the intrinsic apoptotic pathway. In addition, fucoidan treatment of SKM‑1 cells resulted in the generation of reactive oxygen species (ROS) as determined by staining with dichloro-dihydro-fluorescein diacetate. These results suggested that the mechanisms of the anti‑cancer effects of fucoidan in SKM‑1 are closely associated with cell cycle arrest and apoptotic cell death, which partly attributed to the activation of apoptotic pathways and accumulation of intracellular ROS. Our results demonstrated that Fucoidan inhibits proliferation and induces the apoptosis of SKM‑1 cells, which provides substantial therapeutic potential for MDS treatment.
    Preview · Article · Aug 2015 · Molecular Medicine Reports
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    ABSTRACT: Bcr/Abl fusion protein is a hallmark of human chronic myeloid leukemia (CML). The protein can activate various signaling pathways to make normal cells transforme malignantly and thus to facilitates tumorigenesis. It has been reported that heat shock protein-70 (HSP-70) can be served as an anti-apoptotic protein that suppresses Bax and Apo-2L/TRAIL. But it is unclear that whether HSP-70 affects AIF-initiated apoptosis in Bcr/Abl expressing cells considering that HSP-70 is coincidentally over-regulated in these cells. Our findings supported that abundant HSP-70 in Bcr/Abl cells neutralizes AIF by segregating it from nucleus via direct interaction, leading to the failure of AIF initiating cell death and the silence of caspase-independent apoptotic pathway upon apoptotic induction. Moderate inhibition of HSP-70 expression by siRNA leads to Vp-16 triggered re-distribution of AIF in nucleus. In addition, AIF bears a HSP-70 binding domain allowing association with HSP-70. Therefore, disruption of the association using an AIF mutant lacking this domain can restore the potential of AIF importing into nucleus, and finally triggers cell death in a time dependent manner. Copyright © 2015. Published by Elsevier Inc.
    No preview · Article · Jul 2015 · Cellular Signalling
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    ABSTRACT: Secreted protein acidic and rich in cysteine (SPARC) has a complex and pleiotropic biological role in cell life during disease. The role of SPARC in myelodysplastic syndrome (MDS) is not yet fully understood. In the present study, we investigated the role of SPARC protein overproduction in the proliferation and apoptosis of SKM-1 cells, an acute myeloid leukemia cell line transformed from MDS. SKM-1 cells were infected with the pGC-GV-SPARC vector. The cells were then assessed for proliferation and cell death following treatment with low-dose cytosine arabinoside (Ara‑C). The microarray analysis results revealed that samples from SPARC‑overexpressed cells compared to SPARC protein, in SKM-1 cells led to proliferation inhibition and promoted programmed cell death and these effects were greater when treated with Ara-C. The mRNA and protein expression levels of SPARC were detected by SPARC overexpression in cells treated with Ara-C resulting in a significant upregulation of the mixed lineage kinase domain-like (MLKL) gene expression and five other genes. The results showed that the necrotic signaling pathway may play a role when the two conditions were combined via the upregulation of the MLKL protein. MLKL upregulation in SPARC overexpressed cells treated with Ara-C, indicates necrosis as a possible cell death process for the SKM-1 cells under these stringent conditions.
    No preview · Article · Jul 2015 · Oncology Reports
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    ABSTRACT: Secreted protein acidic and rich in cysteine (SPARC) plays key roles in erythropoiesis; haploinsufficiency of SPARC is implicated in the progression of the 5q- syndrome. However, the role of SPARC in other subtypes of myelodysplastic syndrome (MDS) is not fully understood, particularly in the del(5q) type with a complex karyotype, which has a high risk to transform into acute myeloid leukemia (AML). In the present study, we investigated the role of SPARC in the proliferation and apoptosis of SKM-1 cells, an acute myeloid leukemia cell line transformed from an MDS cell line. SKM-1 cells were infected with SPARC-RNAi-LV or NC-GFP-LV lentivirus. Apoptosis and cell cycle profiling were assessed by flow cytometry, and cell proliferation was evaluated by MTS assay. The mRNA and protein expression levels of SPARC, p53, caspase-3, caspase-9 and Fas were detected by RT-PCR, real-time PCR and western blot assay. The SPARC shRNA constructed by us led to a significant reduction in SPARC expression in SKM-1 cells. SPARC knockdown inhibited the proliferation of SKM-1 cells by inducing cell cycle arrest at the G1/G0 phase and apoptosis. SPARC knockdown elevated the expression of p53, caspase-9, caspase-3 and Fas at both the mRNA and protein levels. SPARC silencing inhibited the growth of AML transformed from MDS by activating p53-induced apoptosis and cell cycle arrest. These data indicate that SPARC acts as an oncogene in transformed MDS/AML and is a potential therapeutic target in MDS/AML.
    Preview · Article · Feb 2014 · International Journal of Molecular Medicine
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    ABSTRACT: The chimeric Bcr-Abl oncoprotein, which causes chronic myeloid leukemia, mainly localizes in the cytoplasm, and loses its ability to transform cells after moving into the nucleus. Here we report a new strategy to convert Bcr-Abl to be an apoptotic inducer by altering its subcellular localization. We show that a rapalog nuclear transport system (RNTS) containing six nuclear localization signals directs Bcr-Abl into the nucleus and that nuclear entrapped Bcr-Abl induces apoptosis and inhibits proliferation of CML cells by activating p73 and shutting down cytoplasmic oncogenic signals mediated by Bcr-Abl. Coupling cytoplasmic depletion with nuclear entrapment of Bcr-Abl synergistically enhances the inhibitory effect of nuclear Bcr-Abl on its oncogenicity in mice. These results provide evidence that direction of cytoplasmic Bcr-Abl to the nucleus offers an alternative CML therapy.
    Preview · Article · Oct 2013 · Oncotarget
  • Li Wang · Jing Luo · Qing Nian · Qing Xiao · Zesong Yang · Lin Liu
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    ABSTRACT: Ribosomal protein S14 (RPS14) plays a key role in erythropoiesis and causes p53 activation in 5q- syndrome. However, the oncogenic potential of RPS14 is not understood in leukemia and high-risk myelodysplastic syndrome (MDS). Here, we investigated the changes of proliferation and apoptosis of SKM-1, an acute myeloid leukemia (MDS/AML) cell line transformed from MDS, and explored the role of RPS14 in them. SKM-1 cells were transfected with recombined lentiviral vector shRPS14. Reverse-transcribed polymerase chain reaction and western blot assay were carried to detect the expression of RPS14 and p53. Cell proliferation was determined by MTT assay. Cell cycle and apoptosis were detected through flow cytometry. When compared with negative control, the proliferation rate of SKM-1 cells transfected with RPS14 hairpin siRNA dropped by 30%. Transfected SKM-1 cells presented with activation of p53. Transfection also arrested cells in G0/G1 phase and induced apoptosis, indicating that RPS14 is involved in the pathophysiology of MDS/AML. These findings indicate that partial silencing of RPS14 inhibits the proliferation of MDS/AML cells, and RPS14 may negatively regulate p53 activation in MDS/AML cells.
    No preview · Article · Sep 2013 · Hematology (Amsterdam, Netherlands)
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    ABSTRACT: Selective inhibition of BCR/ABL expression by RNA interference has been demonstrated as an effective strategy in CML treatment and a reversal to imatinib resistance. microRNAs (miRNAs) are small regulatory RNAs involved in post-transcriptional gene regulation. miR-203 is supposed to directly regulate ABL and BCR/ABL expression, however, the role of miR-203 in imatinib-resistant cells is not clear. Here, we report that overexpression of miR-203 in BaF3-BCR/ABL cells with T315I mutant inhibited cell growth and colony formation ability. Furthermore, miR-203 increased sensitivity to imatinib in BaF3-BCR/ABL(T315I) cells, thereby antagonizing the main mechanism of resistance to imatinib.
    Full-text · Article · Apr 2013 · PLoS ONE
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    ABSTRACT: MicroRNAs (miRNAs) are small RNAs that regulate gene expression posttranscriptionally and are critical for many cellular pathways. Recent evidence has shown that aberrant miRNA expression profiles and unique miRNA signaling pathways are present in many cancers. Here, we demonstrate that miR-29b is markedly lower expressed in CML patient samples. Bioinformatics analysis reveals a conserved target site for miR-29b in the 3'-untranslated region (UTR) of ABL1. miR-29b significantly suppresses the activity of a luciferase reporter containing ABL1-3'UTR and this activity is not observed in cells transfected with mutated ABL1-3'UTR. Enforced expression of miR-29b in K562 cells inhibits cell growth and colony formation ability thereby inducing apoptosis through cleavage of procaspase 3 and PARP. Furthermore, K562 cells transfected with a siRNA targeting ABL1 show similar growth and apoptosis phenotypes as cells overexpression of miR-29b. Collectively, our results suggest that miR-29b may function as a tumor suppressor by targeting ABL1 and BCR/ABL1.
    No preview · Article · Feb 2013 · Experimental Cell Research
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    ABSTRACT: Minimal residual disease (MRD) occurrence with some chemotherapy drugs that promote tumor cell escape is also a key factor in blood malignancy relapse. We observed that cytarabine promotes multiple myeloma (MM) cell escape and that the number of cells in the lower chamber increased with increasing clinical disease stage in vitro model which was constructed by a Boyden chamber, matrigel glue and serum from MM patients in different disease stages. The mechanism of cytarabine promotes MM cell escape is closely associated with the up-regulation of CXCR4. SDF-1α can up-regulate the expression of MMP9 and RHoC proteins in MM cells with up-regulated CXCR4, and further promote the cell escape. Fucoidan, a sulfated polysaccharide in the cell wall matrix of brown algae, has attracted much attention for its multiple biological activities, and we further explored the effects and possible underlying mechanisms of fucoidan on MM cell escape from cytarabine cytotoxicity. The results show that fucoidan may decrease MM cell escape from cytarabine cytotoxicity, and that fucoidan can down-regulate CXCR4, MMP9 and RHoC expression. This research provides new direction for investigating MRD occurrence and prevention.
    No preview · Article · Dec 2012 · Fitoterapia
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    ABSTRACT: Chronic myeloid leukemia (CML) is a clonal hematologic malignancy characterized by the BCR-ABL protein. BCR-ABL is a constitutively active tyrosine kinase and plays a critical role in the pathogenesis of CML. Imatinib mesylate, a selective tyrosine kinase inhibitor, is effective in CML, but drug resistance and relapse occur. The coiled-coil (CC) domain located in BCR(1-72) mediates BCR-ABL tetramerization, which is essential for the activation of tyrosine kinase and transformation potential of BCR-ABL. CC domain is supposed to be a therapeutic target for CML. We purified a TAT-CC protein competively binding with the endogenous CC domain to reduce BCR-ABL kinase activity. We found that TAT-CC co-located and interacted with BCR-ABL in Ba/F3-p210 and K562 cells. It induced apoptosis and inhibited proliferation in these cells. It increased the sensitivity of these cells to imatinib and reduced the phosphorylation of BCR-ABL, CRKL and STAT5. We confirmed that TAT-CC could attenuate the oncogenicity of Ba/F3-p210 cells and diminish the volume of K562 solid tumor in mice. We conclude targeting the CC may provide a complementary therapy to inhibit BCR-ABL oncogenicity.
    No preview · Article · Jul 2012 · Amino Acids
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    ABSTRACT: Chronic myeloid leukemia (CML) is a malignant blood disease originating from hematopoietic stem cells. Drug resistance and tumor recurrence have become major problems for the treatment of this disease. Therefore, new therapeutic methods need to be developed. Antigens expressed on the surface of cancer cells are potential targets for antibody-mediated drug delivery. In our study, an anti-CML cell single-chain variable fragment (scFv) antibody has been produced and characterized because it is the first step towards the construction of a novel cancer-targeted agent for cancer diagnosis and treatment. Here, a 46 kDa antibody derivative was produced by genetic fusion of a humanized scFv antibody against a CML cell surface antigen with the 6xHis-tag, which can specifically bind to CML cells. The recombinant scFv against CML cells was expressed as a fusion protein containing the 6xHis-tag at its N-termini, and purified by Ni2+-NTA column chromatography. The recombinant scFv, which was soluble, was expressed and produced in bacteria, and was confirmed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and western blot assays. Finally, its cell-binding activity and immunoactivity were demonstrated by enzyme-linked immunosorbent assay (ELISA). Furthermore, flow cytometry analysis demonstrated that this scFv specifically targeted CML cells expressing the associated antigen (47.9 and 34.4%) other than non-expressing tumor cells (1.25%) in vitro. The results presented in this study illustrate that the humanized anti-CML cell scFv antibody may function as a novel therapeutic tool for CML.
    Preview · Article · May 2012 · International Journal of Molecular Medicine
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    ABSTRACT: To construct a lentiviral vector expressing small-hairpin RNA(shRNA) targeting SPARC gene and investigate its silenced effect on SPARC in human myelodysplastic syndromes(MDS) cell line SKM-1. The targeting sequence of SPARC gene which can be effectively silenced in RNA interference was confirmed in our previous study. The designed and synthesized single-stranded primers were annealed to double-stranded oligo sequences and subcloned into linear pGCSIL-GFP lentiviral plasmid digested by enzyme Age I and EcoR I to produce GC-shSPARC lentiviraL vector. After being identified by PCR and sequencing, plasmids GC-shSPARC with pHelper 1.0 and pHelper 2.0 were cotransfected into 293T cells to package lentiviral particles. The recombinant lentiviral vector was transfected into human SKM-1 cells, transfection efficiency was evaluated with expression of green fluorescent protein(GFP) determined by fluorescent microscope. Expression of SPARC in SKM-1 cells was detected using RT-PCR and Western blotting. A recombinant lentiviral vector, GC-shSPARC, expressing shRNAs targeting SPARC gene was constructed and confirmed by DNA sequencing. The recombinant lentivirus was harvested from 293T cells with a viral titer of 1×10(9); TU/mL. GFP was observed in the 70% of SKM-1 cells after transfection. Expression of SPARC mRNA and protein was significantly reduced in the GC-shSPARC transfected group than that in the control group (P<0.05). The lentivirus RNAi vector targeting SPARC has been successfully constructed, and can effectively inhibit the expression of SPARC in SKM-1 cell line, which shed light on the foundation for researching the inhibition of SPARC siRNA target against human MDS cells proliferation, induction apoptosis and gene therapy.
    No preview · Article · May 2012 · Xi bao yu fen zi mian yi xue za zhi = Chinese journal of cellular and molecular immunology
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    ABSTRACT: Chimeric T cell receptors (chTCRs), composed of the single-chain variable fragments (scFv) of murine antibodies and human signaling molecules, are used to redirect the specificity of autologous or allogeneic T lymphocytes. To develop novel therapeutic agents for treatment of chronic myeloid leukemia (CML), we engineered a scFv from the hybridoma cell line CMA1 which produces monoclonal antibody specific against CML. The genes encoding the heavy and light chain variable regions were amplified from CMA1 cDNA and a humanized chTCR was constructed. Expression of the novel hchTCR was verified in NIH3T3 cells transduced with retroviral vectors. The results demonstrated that hchTCR can be expressed and presented on cell surface normally. These results suggest that retroviral vectors expressing hchTCR specific for CML cells may be used to redirect human T lymphocytes.
    No preview · Article · Mar 2012 · Biotechnology Letters
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    ABSTRACT: To construct a recombinant adenovirus vector for SH2-DED fusion gene and assess its inhibitory effect on the proliferation of K562 cells. SH2-DED fusion gene and its mutant SH2mt-DED were amplified by splicing PCR and cloned into pAdTrack-CMV plasmid separately to construct the shuttle plasmids pAdT-SD-EGFP and pAdT-SmD-EGFP, respectively. After Pme I digestion, the shuttle plasmids were transformed into ultra-competent pAd5F35-BJ5183 cells to generate defective adenovirus vectors pAd5F35-SD-EGFP and pAd5F35- SmD-EGFP by homologous recombination. The vectors, linearized by Pac I digestion, were further transfected into AD293 cells for packaging and amplified by infecting AD293 cells repeatedly. K562 cells were then infected by the recombinant adenoviruses and the expression of SD was detected by Western blotting. MTT assay and flow cytometry were used to investigate the effect of Ad5F35-SD-EGFP and Ad5F35-SmD-EGFP on the proliferation of K562 cells. The recombinant adenovirus vectors pAd5F35-SD-EGFP and pAd5F35-SmD-EGFP were constructed correctly, with a titer reaching 1.5×10(12) pfu/ml after amplification. Western blotting demonstrated that the target proteins were effectively expressed in transfected K562 cells. MTT assay and flow cytometry showed that transfection with pAd5F35-SD-EGFP resulted in growth inhibition rate of 55.21% in K562 cells, significantly higher than the inhibition rate of 17.95% following transfection with pAd5F35- SmD-EGFP and 7.33% following PBS treatment (P<0.05). The recombinant adenovirus vector Ad5F35-SD-EGFP we constructed can significantly inhibit the proliferation of K562 cells in vitro. Key words: Bcr-Abl; SH2; DED; recombinant adenovirus; AD293 cellS.
    No preview · Article · Nov 2011 · Nan fang yi ke da xue xue bao = Journal of Southern Medical University
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    ABSTRACT: BCR-ABL oncoprotein is the cause of chronic myeloid leukemia. The homologous oligomerization of BCR-ABL protein mediated by BCR coiled-coil (CC) domain plays an important role in ABL kinase activation. The HIV-1 TAT peptide has been used extensively for the introduction of proteins into cells. We recombinated a TAT-CC-HA protein to interrupt the homologous oligomerization of BCR-ABL. The expression conditions for TAT-CC-HA were optimized. The TAT-CC-HA fusion protein was purified with Ni+-NTA resin. TAT-CC-HA fusion protein was added into the cultures of Ba/F3-p210, 32D-p210, K562, KU812, Ba/F3, 32D, and HL-60 cells. It was found that TAT-CC-HA could transduce into these cells. It was confirmed that TAT-CC-HA fusion protein was internalized by Ba/F3-p210, K562, and Ba/F3 cells and located in the cytoplasm observed by confocal laser scanning fluorescence microscope. The transduction of TAT-CC-HA fusion protein into K562 cells was in a dose-dependent and time-dependent manner. The result of coimmunoprecipitation assay indicated that TAT-CC-HA could interact with BCR-ABL in K562 cells. The effects of TAT-CC-HA fusion protein on cell growth and apoptosis were detected by MTT test and flow cytometry. Our findings suggested that TAT-CC-HA fusion protein could specifically inhibit the growth of BCR-ABL positive cells, and specifically induce apoptosis of BCR-ABL positive cells, while not affect the growth and apoptosis of BCR-ABL negative cells.
    No preview · Article · May 2011 · Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie
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    ABSTRACT: 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.
    No preview · Article · Dec 2009 · Pathology & Oncology Research
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    ABSTRACT: 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.
    No preview · Article · Jul 2009 · Protein Expression and Purification
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    ABSTRACT: 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 μM. 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.
    No preview · Article · Apr 2009 · Protein Expression and Purification

Publication Stats

108 Citations
46.56 Total Impact Points

Institutions

  • 2009-2015
    • Chongqing Medical University
      Ch’ung-ch’ing-shih, Chongqing Shi, China