Xiulian Zhang

Yamaguchi University, Yamaguchi-shi, Yamaguchi-ken, Japan

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Publications (18)47.18 Total impact

  • Article: Proteomic differential display identifies upregulated vinculin as a possible biomarker of pancreatic cancer.
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    ABSTRACT: Pancreatic cancer (PC) is characterized by rapid tumor spread, and very few patients with PC survive for more than 5 years. It is imperative to discover additional diagnostic biomarkers or specific therapeutic targets in order to improve the treatment of patients with PC. In search for useful biomarkers, we analyzed ten pairs of non-cancerous and cancer tissues from patients with PC by two-dimensional gel electrophoresis (2-DE). Nineteen protein spots showed differential expression on 2-DE gels between the cancer and non-cancerous tissues. Six upregulated protein spots were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS) as calreticulin, glutathione synthetase, stathmin, vinculin, α-enolase and glyceraldehyde-3-phosphate dehydrogenase. Western blotting demonstrated that vinculin was predominantly expressed in the pancreatic cancer tissues compared with to non-cancerous tissues. Our findings indicate that vinculin may be a clinically useful biomarker of PC.
    Oncology Reports 08/2012; 28(5):1845-50. · 1.84 Impact Factor
  • Article: Differential expression of up-regulated cofilin-1 and down-regulated cofilin-2 characteristic of pancreatic cancer tissues.
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    ABSTRACT: Pancreatic cancer (PC) is one of the most deadly malignant tumors. The aim of this study was to identify potential biomarkers for PC. Using two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry, the proteomic profiles of pancreatic cancerous and non-cancerous tissues from ten patients with PC were compared. One of the numerous spots that showed stronger intensity in cancerous compared to non-cancerous tissues was identified as non-muscle cofilin (cofilin-1). This up-regulation was validated by Western blot analysis. It is noteworthy that Western blot analysis showed significantly lower expression of muscle cofilin (cofilin-2) in pancreatic cancerous tissues compared to non-cancerous tissues. This is the first time that cofilin isoforms (cofilin-1/2) have been identified to be differentially expressed in pancreatic cancerous tissues. Therefore, cofilin isoforms may serve as candidates for clinically useful biomarkers or therapeutic targets for PC.
    Oncology Reports 09/2011; 26(6):1595-9. · 1.84 Impact Factor
  • Article: Screening for serological biomarkers of pancreatic cancer by two-dimensional electrophoresis and liquid chromatography-tandem mass spectrometry.
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    ABSTRACT: Pancreatic cancer (PC) is one of the most lethal malignant tumors because of late diagnosis and the lack of response to various therapies. To identify potential biomarkers in cancerous serum from early stage PC patients, we carried out two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) to compare the serum proteomic profiles from 45 patients with PC and 20 healthy volunteers. Seven spots showed differential expression on 2-DE gels and two up-regulated protein spots were identified by LC-MS/MS as α-1-antitrypsin (AAT). These protein spots were also confirmed by Western blotting. This is the first time that AAT isoforms have been identified as potential serum biomarkers for PC. The serum isoforms of AAT may be clinically useful for PC diagnosis and monitoring.
    Oncology Reports 07/2011; 26(1):287-92. · 1.84 Impact Factor
  • Article: Identification of differentially expressed proteins in tumour necrosis factor-alpha-resistant and -sensitive rat hepatoma cells.
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    ABSTRACT: Our earlier studies reported that ONO-4007, a synthetic lipid A analogue with low endotoxic activity, had shown much effect on tumour necrosis factor (TNF)-alpha-sensitive rat hepatoma cells, even though it had no effect on TNF-alpha-resistant cells. To find biomarkers which relate to the sensitivity of cancer cells to TNF-alpha, proteomic differential display analysis for TNF-alpha-resistant cKDH-8/11 and -sensitive KDH-8/YK rat hepatoma cell lines was carried out using two-dimensional gel electrophoresis and liquid chromatography-tandem mass spectrometry. Two-DE analysis showed 32 spots, whose expression was different between cKDH-8/11 cells and KDH-8/YK cells. Of these, 12 were up-regulated and 20 were down-regulated in cKDH-8/11 cells compared to KDH-8/YK cells. The up-regulated proteins include transitional endoplasmic reticulum ATPase, 78 kDa glucose-regulated protein (GRP78), heat-shock cognate 71 kDa protein (HSC71) and protein disulfide-isomerase A6. The down-regulated proteins included alpha-enolase, aldose reductase, glutathione reductase, annexin A1, glutamate dehydrogenase 1 and dihydrolipoyl dehydrogenase. These findings suggest that these differentially regulated proteins could be factors responsible for the resistance of cKDH-8/11 cells to TNF-alpha-induced cell death.
    Anticancer research 06/2011; 31(6):2059-63. · 1.73 Impact Factor
  • Article: Proteomic differential display analysis for TS-1-resistant and -sensitive pancreatic cancer cells using two-dimensional gel electrophoresis and mass spectrometry.
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    ABSTRACT: TS-1 is an oral anticancer agent containing two biochemical modulators for 5-fluorouracil (5-FU) and tegafur (FT), a metabolically activated prodrug of 5-FU. TS-1 has been recognized as an effective anticancer drug using standard therapies for patients with advanced pancreatic cancer along with gemcitabine. However, a high level of inherent and acquired tumor resistance to TS-1 induces difficulty in the treatment. To identify proteins linked to the TS-1-resistance of pancreatic cancer, we profiled protein expression levels in samples of TS-1-resistant and -sensitive pancreatic cancer cell lines by using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The cytotoxicity of a 5-FU/5-chloro-2,4-dihydroxypyridine (CDHP) combination towards pancreatic cancer cell lines was evaluated by MTS assay. Panc-1, BxPC-3, MiaPaCa-2 and PK59 showed high sensitivity to the 5-FU/CDHP combination (TS-1-sensitive), whereas PK45p and KLM-1 were much less sensitive (TS-1-resistant). Proteomic analysis showed that eleven spots, including T-complex protein 1 subunit beta, ribonuclease inhibitor, elongation factor 1-delta, peroxiredoxin-2 and superoxide dismutase (Cu-Zn), appeared to be down-regulated, and 29 spots, including hypoxia up-regulated protein 1, lamin-A/C, endoplasmin, fascin and annexin A1, appeared to be up-regulated in TS-1-resistant cells compared with -sensitive cells. These results suggest that the identified proteins showing different expression between TS-1-sensitive and -resistant pancreatic cancer cells possibly relate to TS-1-sensitivity. These findings could be useful to overcome the TS-1-resistance of pancreatic cancer cells.
    Anticancer research 06/2011; 31(6):2103-8. · 1.73 Impact Factor
  • Article: Two-dimensional gel electrophoresis using immobilized pH gradient strips and FlamingoTM fluorescent gel stain identified non-nuclear proteins possibly related to malignant tumour progression.
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    ABSTRACT: The understanding of tumour progression is one of the most important strategies to conquer tumour. QR-32 is a regressive murine fibrosarcoma cell line, and QRsP-11 is a progressive malignant tumour cell clone derived from QR-32. Ina recently published study a differential display analysis for the cytoplasmic proteins was shown by using two-dimensional gel electrophoresis (2-DE) making full use of isoelectric focusing capillary gels and Coomassie brilliant blue R-250 staining. Furthermore, a differential display analysis of the nuclear proteome for QR-32 and QRsP-11 was performed. The present study shows a non-nuclear proteomic differential display analysis, using 2-DE making full use of immobilized pH gradient strips and Flamingo™ fluorescent gel stain, between QR-32 and QRsP-11 to identify particular proteins which may be involved in malignant progression. In QRsP-11 25 proteins were up-regulated, including hypoxia up-regulated protein 1, and 6 were down-regulated compared with QR-32. These results suggest that the identified non-nuclear proteins showing different expression between QR-32 and QRsP-11 possibly related to malignant tumour progression.
    Anticancer research 04/2011; 31(4):1259-63. · 1.73 Impact Factor
  • Article: Proteomic differential display analysis shows up-regulation of 14-3-3 sigma protein in human scirrhous-type gastric carcinoma cells.
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    ABSTRACT: This study performed proteomic differential display analysis of human scirrhous-type gastric carcinoma (SGC) cell lines and normal gastric mucosa (NGM) tissues by using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). The human SGC cell lines were OCUM-1, OCUM-2M, OCUM-2MLN, OCUM-2D, OCUM-D3, OCUM-9 and OCUM-12. Among the SGC cell lines and the NGM tissues, 28 protein spots were found whose expression levels were different from the results of 2-DE: 19 protein spots appeared higher, and 9 other protein spots appeared lower in SGCs than in NGM tissues. These spots were analysed by LC-MS/MS analysis and identified by a peptide sequence tag. Identified increased spots included elongation factor 1-beta, 14-3-3 sigma, tropomyosin alpha-4 chain, protein DJ-1, nucleoside diphosphate kinase A, elongation factor Tu and peroxiredoxin-1. Western blot analysis showed increased protein level of 14-3-3 sigma in SGCs. Although OCUM-1 and AGS (gastric cancer) showed up-regulation of 14-3-3 sigma, MiaPaca-2 (pancreatic cancer), Huh-7 (HCC) and NCI-H2052 (malignant pleural mesothelioma) showed very weak expression of 14-3-3 sigma. The up-regulation of 14-3-3 sigma may play an important role in SGC carcinogenesis and progression and may be used as a diagnostic biomarker of SGC.
    Anticancer research 11/2010; 30(11):4459-65. · 1.73 Impact Factor
  • Article: Staining with highly sensitive Coomassie brilliant blue SeePico™ Stain after Flamingo™ fluorescent gel stain is useful for cancer proteomic analysis by means of two-dimensional gel electrophoresis.
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    ABSTRACT: Highly sensitive Coomassie brilliant blue SeePico™ Stain was applied for proteomic analysis using two-dimensional gel electrophoresis (2-DE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). After staining with Flamingo™ Fluorescent Gel Stain, the images of the protein spots were analyzed, and 424 protein spots were detected. After washing with Milli-Q water three times, the gels were re-stained with SeePico™ Stain and the images of the protein spots were analyzed; 272 spots were detected. To assess whether SeePico™ Stain alters MS analysis, a spot was picked up and was analyzed by LC-MS/MS. The MS analysis showed good protein identification. These results show a possible role for SeePico™ Stain in cancer proteomics using 2-DE and MS.
    Anticancer research 10/2010; 30(10):4001-5. · 1.73 Impact Factor
  • Article: Identification of up- and down-regulated proteins in gemcitabine-resistant pancreatic cancer cells using two-dimensional gel electrophoresis and mass spectrometry.
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    ABSTRACT: The prognosis of patients with pancreatic cancer is very poor because of late diagnosis and the lack of response to various therapies. Pancreatic cancer is generally resistant to chemotherapy and is highly fatal. Gemcitabine (GEM) appears to be the only effective agent for treatment of pancreatic cancer. However, a high level of inherent and acquired tumor resistance makes the clinical impact of GEM modest. Proteomic differential display analysis for GEM-sensitive human pancreatic adenocarcinoma cell line KLM1 and GEM-resistant KLM1-R cells by using two-dimensional gel electrophoresis and liquid chromatography tandem mass spectrometry produced 33 protein spots. Of these, 23 were up-regulated and 10 were down-regulated in KLM1-R compared to KLM1 cells. The up-regulated proteins include acidic leucine-rich nuclear phosphoprotein 32 family member A, reticulocalbin-1, gamma-synuclein, microtubule-associated protein RP/EB family, sialic acid synthase, peptidyl-prolyl cis-trans isomerase A, far upstream element-binding protein 2 and catalase. The down-regulated proteins include far upstream element-binding protein 1, gamma-synuclein, galectin-1 and stathmin. Two spots of heat-shock protein 27 were up-regulated in KLM1-R cells. These results suggest an important complementary role for proteomics in the identification of proteins which may play a role in the poor response of pancreatic cancer to GEM.
    Anticancer research 09/2010; 30(9):3367-72. · 1.73 Impact Factor
  • Article: Proteomic analysis for nuclear proteins related to tumour malignant progression: a comparative proteomic study between malignant progressive cells and regressive cells.
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    ABSTRACT: Tumour development and progression consists a series of multiple changes in gene expression. Progressive tumour cells acquire more aggressive properties manifested by rapid growth, invasiveness and metastatic ability, as well as increased genetic instability leading to multiple genetic alterations. Therefore, it is crucial to identify the possible intracellular and extracellular molecular mechanisms that accelerate tumour progression, in particular to identify nuclear proteins which interact with DNA. Nuclear proteomics provides an opportunity to qualitatively and quantitatively examine protein effectors that contribute to cellular phenotype. This study performed a differential display analysis for the expression of nuclear proteome between regressive tumour cell clone QR-32 and malignant progressive tumour cell clone QRsP-11 using two-dimensional gel electrophoresis (2-DE) and mass spectrometry (MS). Eight nuclear proteins whose expressions were different between QR-32 and QRsP-11 cells were identified. Seven of those protein spots, zinc finger protein ZXDC, lamin-A/C, far upstream clement-binding protein 1, heterogeneous nuclear ribonucleoprotein K, heterogeneous nuclear ribonucleoprotein A/B and guanine nucleotide-binding protein G(I)/G(S)/G(T) subunit beta-1, were down-regulated in QRsP-11, while one protein, nucleolin, was up-regulated in QRsP-11.
    Anticancer research 06/2010; 30(6):2093-9. · 1.73 Impact Factor
  • Article: Proteomic profiling of differential display analysis for human oral squamous cell carcinoma: 14-3-3 σ Protein is upregulated in human oral squamous cell carcinoma and dependent on the differentiation level.
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    ABSTRACT: Oral squamous cell carcinoma (OSCC) has an absolute majority of all oral cancer. We used proteomic technology to analyze the protein expression profile in OSCC tissues and accompanying surrounding normal tissues in four oral locations (buccal mucosa, gingival mucosa, oral floor, and tongue). Ten protein spots were overexpressed more strongly in cancer tissues than normal ones, and were identified as proliferating cell nuclear antigen, 14-3-3 ε, 14-3-3 σ, proteasome subunit α type 5, translationally controlled tumor protein, eukaryotic translation initiation factor 3 subunit, macrophage capping protein, and mitochondrial isocitrate dehydrogenase subunit α. Macrophage capping protein and mitochondrial isocitrate dehydrogenase subunit α had two spots. Especially, we focused on 14-3-3 σ protein, one of the eight identified proteins, and assessed its expression level in four oral locations of OSCC by using differential display methods. The expression level of 14-3-3 σ protein was upregulated in four locations of oral cavity. Eight proteins which we identified in this study may play an important role in OSCC carcinogenesis and progression and could be used as diagnostic biomarkers of OSCC.
    PROTEOMICS - CLINICAL APPLICATIONS 11/2009; 3(11):1338-47. · 1.81 Impact Factor
  • Article: Proteomic differential display analysis identified upregulated astrocytic phosphoprotein PEA‐15 in human malignant pleural mesothelioma cell lines
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    ABSTRACT: We performed proteomic differential display analysis of human malignant pleural mesothelioma (MPM) cell lines and a human pleural mesothelial cell line by using 2-DE and LC-MS/MS. The human MPM cell lines were NCI-H28, NCI-H2052 and NCI-H2452, and the human pleural mesothelial cell line was MeT-5A. Between MeT-5A and NCI-H2052, we found 38 protein spots whose expression levels were different, from the results of 2-DE; 28 protein spots appeared higher, and 10 other protein spots lower in NCI-H2052 than in MeT-5A. These spots were analyzed by LC-MS/MS analysis and identified by a peptide sequence tag. However, from the results of 2-DE of the other cell lines, there was only one consistently upregulated protein, astrocytic phosphoprotein PEA-15, in all three MPM cell lines. Western blotting using specific antibodies against PEA-15 confirmed the elevated expression level of PEA-15 in all three MPM cell lines compared with MeT-5A cells and normal pleura tissues from patients. PEA-15 was knocked down in NCI-H2052 cells, and the proliferation of PEA-15-silenced NCI-H2052 cells was suppressed 7–15% compared with negative control cells. These results suggest that PEA-15 expression is likely to be associated with the tumorigenesis of MPM.
    Proteomics 09/2009; 9(22):5078 - 5089. · 4.43 Impact Factor
  • Article: Proteomic differential display analysis identified upregulated astrocytic phosphoprotein PEA-15 in human malignant pleural mesothelioma cell lines.
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    ABSTRACT: We performed proteomic differential display analysis of human malignant pleural mesothelioma (MPM) cell lines and a human pleural mesothelial cell line by using 2-DE and LC-MS/MS. The human MPM cell lines were NCI-H28, NCI-H2052 and NCI-H2452, and the human pleural mesothelial cell line was MeT-5A. Between MeT-5A and NCI-H2052, we found 38 protein spots whose expression levels were different, from the results of 2-DE; 28 protein spots appeared higher, and 10 other protein spots lower in NCI-H2052 than in MeT-5A. These spots were analyzed by LC-MS/MS analysis and identified by a peptide sequence tag. However, from the results of 2-DE of the other cell lines, there was only one consistently upregulated protein, astrocytic phosphoprotein PEA-15, in all three MPM cell lines. Western blotting using specific antibodies against PEA-15 confirmed the elevated expression level of PEA-15 in all three MPM cell lines compared with MeT-5A cells and normal pleura tissues from patients. PEA-15 was knocked down in NCI-H2052 cells, and the proliferation of PEA-15-silenced NCI-H2052 cells was suppressed 7-15% compared with negative control cells. These results suggest that PEA-15 expression is likely to be associated with the tumorigenesis of MPM.
    Proteomics 09/2009; 9(22):5078-89. · 4.43 Impact Factor
  • Article: Nuclear protein profiling of Jurkat cells during heat stress-induced apoptosis by 2-DE and MS/MS.
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    ABSTRACT: Heat stress causes severe constraints on numerous physiological functions of cells, such as the repression of splicing of mRNA precursors. In this study, we performed proteomic profiling of a nuclear fraction of Jurkat cells during heat stress using 2-DE and LC-MS/MS. We found 10 protein spots whose expression had changed after heat stress at 43 degrees C for 30 min. Seven of those protein spots, periodic tryptophan protein 1 homolog (PWP1), importin beta-1 subunit, sumoylated protein, splicing factor 3a subunit 3 (SF3a3), TAR DNA-binding protein 43, U2 small nuclear ribonucleoprotein auxiliary factor 35 kDa subunit (U2AF35) and small ubiquitin-related modifier-1 (SUMO-1) were downregulated, while three other protein spots, Protein SET, 40S ribosomal protein SA and 60S acidic ribosomal protein P0 were upregulated by the heat stress. We focused on the downregulation of two splicing factors, which might participate in the repression of pre-mRNA processing by heat stress, leading to cell apoptosis.
    Electrophoresis 07/2007; 28(12):2018-26. · 3.30 Impact Factor
  • Article: Proteomic analysis of macrophages stimulated by lipopolysaccharide: Lipopolysaccharide inhibits the cleavage of nucleophosmin.
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    ABSTRACT: Lipopolysaccharide (LPS) is a complex glycolipid composed of a hydrophilic polysaccharide and a hydrophobic domain that is responsible for the biological activity of LPS. There are many reports about LPS stimulation, and many activated proteins have been detected after LPS stimulation in various cell types. Furthermore, most of the LPS signaling pathways are clear. However, we were interested in examining the changes of LPS-induced total cytosolic proteins expression and the LPS signaling pathway by the proteomics technique during LPS-induced macrophage activation. Our study employed two-dimensional gel electrophoresis and mass spectrometry to analyze the proteins involved in LPS-induced activation in RAW 264.7 cells. We found 11 protein spots whose expression was different between untreated cells and LPS-treated cells. Ten protein spots were identified, seven of which, tubulin beta-4 chain (49.6 kDa, pI 4.78), nucleophosmin (32.6 kDa, pI 4.62, two spots), 40S ribosomal protein SA (P40) (32.7 kDa, pI 4.74), transforming protein RhoA (21.8 kDa, pI 5.83), nucleolin (76.6 kDa, pI 4.69), and T-complex protein 1 zeta subunit (58 kDa, pI 6.63) were down-regulated, and three of which, nucleophosmin (32.6 kDa, pI 4.62, two spots) and proteosome subunit alpha type-1 (29.5 kDa, pI 6.00), were up-regulated. The suppression of the proteolytic degradation of nucleophosmin was associated with LPS-induced RAW 264.7 cell activation. Cleaved caspase-3 decreased, thus it might be involved in proteolysis of nucleophosmin in LPS-induced macrophage activation. Our study also demonstrated that there was no change of the expression of nucleophosmin at the mRNA level.
    Electrophoresis 05/2006; 27(8):1659-68. · 3.30 Impact Factor
  • Article: Increased expression and phosphorylation of liver glutamine synthetase in well-differentiated hepatocellular carcinoma tissues from patients infected with hepatitis C virus.
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    ABSTRACT: Hepatocellular carcinoma (HCC) is one of the most common fatal cancers, and chronic infection with hepatitis C virus (HCV) is thought to be one of the main causes in Japan. To identify diagnostic or therapeutic biomarkers for HCC associated with HCV (HCV-HCC), we tried to elucidate the factors related to the products from cancerous tissues of HCV-infected patients. From proteomic differential display analysis of liver tissue samples from HCV-HCC cancerous tissues and corresponding non-cancerous tissues from patients, three protein spots of the same molecular mass (42 kDa), whose expression increased in well-differentiated cancerous tissues, were detected. Although their pI were different, they were identified as glutamine synthetase (GS) by PMF with MALDI-TOF MS and by Western blotting using anti-GS specific mAb. Immunohistochemical analysis showed that tumor tissue consists of two parts, GS-positive cell and GS-negative cell regions, suggesting that GS-producing cells grew in the tumor tissue as a nodule in nodules. The tryptic peptides of the most acidic GS isoform lost the signal of 899.5 Da, corresponding a peptide of SASIRIPR, and gained a signal of 1059.5 Da, which was submitted to PSD analysis. PSD analysis showed the neutral loss by elimination of two phosphate groups, supposed to be on serine residues of the 899.5-Da peptide, from serine 320 to arginine 327 in GS. PMF followed by PSD analysis is thought to be useful for the determination of phosphorylation sites of proteins showing molecular heterogeneity.
    Electrophoresis 05/2006; 27(8):1651-8. · 3.30 Impact Factor
  • Article: Analysis on heat stress-induced hyperphosphorylation of stathmin at serine 37 in Jurkat cells by means of two-dimensional gel electrophoresis and tandem mass spectrometry.
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    ABSTRACT: Two-dimensional gel electrophoresis (2-DE) and tandem mass spectrometry were successfully used for determination of a phosphorylation site of stathmin induced by heat stress to Jurkat cells of a human T lymphoblastic cell line. The cells were incubated for 30 min at 41 degrees C up to 45 degrees C in a serum free 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES) buffered culture medium. The intracellular soluble proteins were separated by 2-DE, and some of the proteins increased their abundance by heat stress. Those proteins were identified to be calmodulin, protein kinase C substrate, thymosin beta-4 and F-actin capping protein beta-subunit by peptide mass fingerprinting (PMF) with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). On the contrary, protein phosphatase 2C gamma-isoform, nucleophosmin, translationally controlled tumor protein, Rho GDP-dissociation inhibitor-1, eukaryotic translation initiation factors 5A and 3A subunit 2, ubiquitin-like protein SMT 3B and chloride intracellular channel protein-1 were decreased their abundance. A protein spot of M(r) 18,000 and pI 5.9 was markedly increased at temperatures higher than 43 degrees C at which the cells were led to apoptosis. The spot was identified to be stathmin of a signal relay protein which has a function of sequestering microtubule. MALDI-quadrupole ion trap (QIT)-TOF-MS/MS and immunoblotting with a monoclonal antibody specific for a phosphorylation site of stathmin showed that the spot was a phosphorylated stathmin at serine 37 (Ser 37). The phosphorylation was suppressed by treatment of cells with olomoucine of an inhibitor specific for cyclin dependent kinase (Cdk-1). These results strongly suggest that heat stress activates Cdk-1 which phosphorylates Ser 37 on the stathmin molecule. The phosphorylation may cause the functional loss of stathmin for dynamic microtubule assembly and leads Jurkat cells to cell cycle arrest and apoptosis.
    Journal of Chromatography 03/2006; 1106(1-2):181-9. · 4.53 Impact Factor
  • Article: Proteomic profiling for cancer progression: Differential display analysis for the expression of intracellular proteins between regressive and progressive cancer cell lines.
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    ABSTRACT: Tumor development and progression consist of a series of complex processes involving multiple changes in gene expression (Paolo et al. Physiol. Rev., 1993, 73, 161-195; Lance et al. Cell., 1991, 64, 327-336). Tumor cells acquire an invasive and metastatic phenotype that is the main cause of death for cancer patients. Therefore, for early diagnosis and effective therapeutic intervention, we need to detect the alterations associated with transition from benign to malignant tumor cells on a molecular basis. To unravel alterations concerned with tumor progression, the proteomic approach has attracted great attention because it can identify qualitative and quantitative changes in protein composition, including post-translational modifications. In this study, we performed proteomic differential display analysis for the expression of intracellular proteins in the regressive cancer cell line QR-32 and the inflammatory cell-promoting progressive cancer cell line QRsP-11 of murine fibrosarcoma by two-dimensional gel electrophoresis and mass spectrometry using an Agilent 1100 LC/MSD Trap XCT. We found 11 protein spots whose expression was different between QR-32 and QRsP-11 cells and identified nine proteins, seven of which, calreticulin precursor, tropomyosin 1 alpha chain, annexin A5, heat shock protein (HSP)90-alpha, HSP90-beta, PEBP, and Prx II, were over-expressed, and two, Anp32e and HDGF, which were down-regulated. The results suggest an important complementary role for proteomics in identification of molecular abnormalities in tumor progression.
    PROTEOMICS 04/2005; 5(4):1024-32. · 4.51 Impact Factor