The protein encoded by TXNDC5 is a member the protein disulfide isomerase family, which has disulfide isomerase activity and can act as the molecular chaperone to reduce the synthesis of abnormal proteins. Its biological functions include anti-oxidation, promoting angiogenesis, taking part in cellular inflammation, and energy metabolism, etc. Studies have demonstrated that the expression of TXNDC5 is increased in many types of tumors including cervical carcinoma, gastric carcinoma and colorectal cancer. Moreover, TXNDC5 is also closely associated with rheumatoid arthritis, diabetes, hepatic steatosis and vitiligo. This paper aims to summarize the latest progress in research on TXNDC5 in terms of biochemical function, relationship with diseases and the underlying mechanism.
Animals ; Arthritis, Rheumatoid ; enzymology ; genetics ; Diabetes Mellitus ; enzymology ; genetics ; Humans ; Neoplasms ; enzymology ; genetics ; Protein Disulfide-Isomerases ; genetics

OBJECTIVE: Protein disulfide isomerase (PDI) acts as a chaperone on the cell surface, and it has been reported that PDI is associated with the tumor cell migration and invasion. The aims of this study are to investigate the anti-migration effect of bacitracin, which is an inhibitor of PDI, and the associated factor in this process. METHODS: U87-MG glioma cells were treated with bacitracin in 1.25, 2.5, 3.75, and 5.0 mM concentrations. Western blot with caspase-3 was applied to evaluate the cytotoxicity of bacitracin. Adhesion, morphology, migration assays, and organotypic brain-slice culture were performed to evaluate the effect of bacitracin to the tumor cell. Western blot, PCR, and gelatin zymography were performed to investigate the associated factors. Thirty glioma tissues were collected following immunohistochemistry and Western blot. RESULTS: Bacitracin showed a cytotoxicity in 3rd (p<0.05) and 4th (p<0.001) days, in 5.0 Mm concentration. The cell adhesion significantly decreased and the cells became a round shape after treated with bacitracin. The migration ability, the expression of phosphorylated focal adhesion kinase (p-FAK) and matrix metalloproteinase-2 (MMP-2) decreased in a bacitracin dose- and time-dependent manner. The U87-MG cells exhibited low-invasiveness in the 2.5 mM, compared with the untreated in organotypic brain-slice culture. PDI was expressed in the tumor margin, and significantly increased with histological glioma grades (p<0.001). CONCLUSION: Bacitracin, as a functional inhibitor of PDI, decreased the phosphorylated FAK and the secreted MMP-2, which are the downstream of integrin and play a major role in cell migration and invasion, might become one of the feasible therapeutic strategies for glioblastoma.
Bacitracin* ; Blotting, Western ; Caspase 3 ; Cell Adhesion ; Cell Movement ; Focal Adhesion Protein-Tyrosine Kinases ; Gelatin ; Glioblastoma ; Glioma* ; Immunohistochemistry ; Matrix Metalloproteinase 2 ; Polymerase Chain Reaction ; Protein Disulfide-Isomerases

OBJECTIVEThis study was aimed to investigate the regulatory effect of protein disulfide isomerase (PDI) on platelet GPIbα ectodomain shedding.

METHODSThe washed platelets were obtained from healthy volunteers. Platelets were incubated with PDI inhibitor bacitracin before stimulation with PMA (Phorbol-12-myristate-13-acetate), dibucaine and collagen. The N-terminal domain of GPIbα in supernatant was detected by Western blot, the GPIbα expression and the intraplatelet ROS levels were measured by flow cytometry.

RESULTSneither GC content nor GPIbα expression was changed after the washed platelets from the healthy donors were incubated only with PDI inhibitor. The washed platelets were incubated with PDI inhibitor before stimulation with different stimulin, PMA, dibucaine or collagen, and then GPIbα was cleaved and ROS levels were elevated more than that in the controls.

CONCLUSIONPDI participates in the induced GPIbα ectodomein shedding, and the effect of PDI in this process maybe depend on the change of ROS level inside platelets. These results might provide a new point of view for the platelet drug development.

Blood Platelets ; Collagen ; Flow Cytometry ; Humans ; Platelet Glycoprotein GPIb-IX Complex ; Protein Disulfide-Isomerases

OBJECTIVETo study the predicting effect of proly 4-hydroxylase beta polypeptide (P4HB) in treating non-small cell lung cancer (NSCLC) patients by Yiqi Chutan Recipe (YCR).

METHODSTotally 46 stage III and IV NSCLC patients were treated by YCR for 4 therapeutic courses. Effect was assessed by RECIST of solid tumor. P4HB expression was detected in the lung cancer tissue by immunohistochemical assay. Factors affecting disease control rates (DCR) of YCR were analyzed by Logistic regression analysis. The correlation between P4HB expression and the effect of YCR was analyzed.

RESULTSThe DCR of advanced NSCLC treated by YCR was 36.96% (17/46 cases). P4HB was high expressed in advanced lung cancer tissue (6/15 cases). Gender, initial treatment, and retreatment are independent factors for affecting DCR of treating lung cancer by YCR.

CONCLUSIONP4HB might be taken as a factor for predicting the effect of YCR in treating NSCLC.

Carcinoma, Non-Small-Cell Lung ; drug therapy ; metabolism ; Drugs, Chinese Herbal ; therapeutic use ; Humans ; Lung ; Lung Neoplasms ; drug therapy ; metabolism ; Male ; Procollagen-Proline Dioxygenase ; metabolism ; Protein Disulfide-Isomerases ; metabolism

The 1,095 bp gene encoding peroxidase from Coprinus cinereus was synthesized and integrated into the genome of Pichia pastoris with a highly inducible alcohol oxidase. The recombinant CiP (rCiP) fused with the a-mating factor per-pro leader sequence derived from Saccharomyces cerevisiae was secreted into the culture medium and identified as the target protein by mass spectrometry, confirming that a C. cinereus peroxidase (CiP) was successfully expressed in P. pastoris. The endoplasmic reticulum oxidoreductase 1 (Ero1) and protein disulfide isomerase (PDI) were co-expressed with rCiP separately and simultaneously. Compared with the wild type, overexpression of PDI and Erol-PDI increaseed Cip activity in 2.43 and 2.6 fold and their activity reached 316 U/mL and 340 U/mL respectively. The strains co-expressed with Erol-PDI was used to high density fermentation, and their activity reached 3,379 U/mL, which was higher than previously reported of 1,200 U/mL.
Coprinus ; enzymology ; Culture Media ; Cytoplasm ; Fermentation ; Glycoproteins ; metabolism ; Mass Spectrometry ; Mating Factor ; Oxidoreductases Acting on Sulfur Group Donors ; metabolism ; Peptides ; Peroxidases ; biosynthesis ; Pichia ; metabolism ; Protein Disulfide-Isomerases ; metabolism ; Protein Folding ; Saccharomyces cerevisiae ; Saccharomyces cerevisiae Proteins ; metabolism

BACKGROUND/AIMS: Protein disulfide isomerase (PDI) has been implicated in the survival and progression of some cancer cells, by compensating for endoplasmic reticulum stress by upregulating the protein-folding capacity. However, its prognostic role in patients with hepatocellular carcinoma (HCC) has not been investigated. METHODS: We collected HCC tissues from 83 HCC patients who underwent surgical resection for an immunohistochemical study of PDI. Overall survival (OS) was measured from the date of surgical resection until the date of death from any cause. Radiological progression was evaluated using the modified Response Evaluation Criteria in Solid Tumors in an independent radiological assessment. RESULTS: PDI expression was found to be increased in human HCC compared to adjacent nontumor tissues. Increased immunopositivity for PDI was associated with a high Edmondson-Steiner grade (p = 0.028). Univariate analysis of patients who had undergone surgical resection for HCC showed that tumor PDI upregulation is a significant risk factor for poor OS (p = 0.016; hazard ratio [HR], 1.980) and time to progression (TTP; p = 0.007; HR, 1.971). Multivariate analyses revealed that high PDI expression was an independent predictor of a shorter TTP (p = 0.015; HR, 1.865) and poor OS (p = 0.012; HR, 2.069). CONCLUSIONS: Upregulated PDI expression is associated with aggressive clinicopathological features of HCC; thus, PDI might serve as an independent prognostic factor and a potential therapeutic target for HCC patients.
Carcinoma, Hepatocellular/*enzymology/pathology ; Female ; Humans ; Kaplan-Meier Estimate ; Liver Neoplasms/*enzymology/pathology ; Male ; Middle Aged ; Prognosis ; Protein Disulfide-Isomerases/*metabolism ; Retrospective Studies ; Tumor Markers, Biological/metabolism

OBJECTIVETo investigate the role of TXNDC5 in serum starvation-induced proliferation inhibition of HeLa cell.

METHODSTXNDC5 was either over-expressed or knocked down by small interfering RNA (siRNA) in HeLa cells which were then cultured in conventional medium or serum starvation medium. The protein level of TXNDC5 was evaluated by Western blot analysis. The mRNA level of TXNDC5 was measured by quantitative real-time PCR. Cell growth rate was determined by cell proliferation assay kit (MTS method). Cell cycle distribution and apoptosis were detected by flow cytometry.

RESULTSSerum starvation mildly reduced the mRNA level of TXNDC5 (P<0.05), but dramatically increased the protein level of TXNDC5 in HeLa cells. The stability of TXNDC5 mRNA remained unchanged. Cycloheximide abolished the serum starvation-induced up-regulation of TXNDC5 protein. Over-expression of TXNDC5 had no effect on cell proliferation. However, suppression of TXNDC5 attenuated the proliferation inhibition of HeLa cell induced by serum starvation (P<0.05), increased the proportion of cells in S phase (P<0.05), but had no effect on cell apoptosis.

CONCLUSIONTXNDC5 mediates serum starvation-induced proliferation inhibition of HeLa cell.

Apoptosis ; Cell Cycle ; Cell Proliferation ; Culture Media ; chemistry ; Gene Knockdown Techniques ; HeLa Cells ; Humans ; Protein Disulfide-Isomerases ; genetics ; metabolism ; Serum ; chemistry

OBJECTIVETo explore the effects of gastrin on the expression of 1,25(OH)2D3-membrane associated rapid response steroid (1,25D3-MARRS) binding protein in rat intestinal epithelium.

METHODSSD rats received intraperitoneal injections of gastrin, omeprazole or physiological saline. The protein expression of 1,25D3-MARRS binding protein in SD rat intestinal was determined with Western blotting and immunohistochemistry, and its mRNA levels determined by RT-PCR. The serum calcium and phosphate levels in the rats were also detected.

RESULTSImmunohistochemistry showed that 1,25D3-MARRS binding protein was expressed mainly in the nuclei, cytoplasm and membrane of the intestinal epithelial cells. Both the protein and mRNA expression levels of 1,25D3-MARRS binding protein were up-regulated after treatments with gastrin and omeprazole (P<0.05), but the serum calcium and phosphate concentrations showed no obvious increase.

CONCLUSION1,25D3-MARRS binding protein, which is widely expressed with versatile functionalities, is regulated by gastrin and shows high potentials in the study of gastrointestinal diseases.

Animals ; Calcitriol ; metabolism ; Epithelial Cells ; drug effects ; metabolism ; Gastrins ; pharmacology ; Intestines ; cytology ; drug effects ; Male ; Protein Disulfide-Isomerases ; metabolism ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo investigate the relationship and significance between endoplasmic reticulum protein 57 (ERp57) gene promoter region methylation with the pathogenesis of cervical lesions in Uighur women.

METHODSThe special software was used to design specific primers of CpG island fragments of ERp57 gene promoter and bisulfite-modified SiHa cancer cell DNA for PCR amplification, cloning and sequencing the target fragments to obtain relevant information of CpG methylation in the gene base sequencs. Seventy-eight fresh tissues of CIN, CSCC and normal control were collected, and the methylation level of ERp57 gene promoter regions in different cervical lesions were identified using Sequenom MassARRAY(DNA) technology.

RESULTSERp57 gene corresponding target fragment contained the 18 CpG sites. All of the CpG sites methylation occurred in SiHa cervical cancer cell genomic DNA. The analysis of the data resulted from the quantitative analysis of single CpG site methylation by Sequenom MassARRAY platform showed that the methylation level between three CpG sites (CpG_1, CpG_5 and CpG_7) from CpG_1, CpG_2, CpG_3.4, CpG_5, CpG_6, CpG_7, CpG_8 and CpG_ 9 had significant differences in the CSCC, CIN or control groups.

CONCLUSIONSAlthough the global methylation level of the ERp57 gene promoter is higher in CSCC than that in CIN and normal control tissues in Uighur women, hypermethylation occurs only in certain CpG islands and sites. This indicates that the regulation of expression by DNA methylation is not CpG island-specific, but varies for individual CpG sites, and may explain to a certain extent the epigenetic mechanisms regulated by Erp57 gene expression.

Adult ; Aged ; Asian Continental Ancestry Group ; ethnology ; genetics ; Carcinoma, Squamous Cell ; genetics ; Cell Line, Tumor ; Cervical Intraepithelial Neoplasia ; genetics ; CpG Islands ; genetics ; DNA Methylation ; Female ; Humans ; Middle Aged ; Promoter Regions, Genetic ; genetics ; Protein Disulfide-Isomerases ; genetics ; Uterine Cervical Neoplasms ; genetics

Disulfide bond-forming (Dsb) protein is a bacterial periplasmic protein that is essential for the correct folding and disulfide bond formation of secreted or cell wallassociated proteins. DsbA introduces disulfide bonds into folding proteins, and is re-oxidized through interaction with its redox partner DsbB. Mycobacterium tuberculosis, a Gram-positive bacterium, expresses a DsbA-like protein ( Rv2969c), an extracellular protein that has its Nterminus anchored in the cell membrane. Since Rv2969c is an essential gene, crucial for disulfide bond formation, research of DsbA may provide a target of a new class of anti-bacterial drugs for treatment of M.tuberculosis infection. In the present work, the crystal structures of the extracellular region of Rv2969c (Mtb DsbA) were determined in both its reduced and oxidized states. The overall structure of Mtb DsbA can be divided into two domains: a classical thioredoxin-like domain with a typical CXXC active site, and an α-helical domain. It largely resembles its Escherichia coli homologue EcDsbA, however, it possesses a truncated binding groove; in addition, its active site is surrounded by an acidic, rather than hydrophobic surface. In our oxidoreductase activity assay, Mtb DsbA exhibited a different substrate specificity when compared to EcDsbA. Moreover, structural analysis revealed a second disulfide bond in Mtb DsbA, which is rare in the previously reported DsbA structures, and is assumed to contribute to the overall stability of Mtb DsbA. To investigate the disulphide formation pathway in M.tuberculosis, we modeled Mtb Vitamin K epoxide reductase (Mtb VKOR), a binding partner of Mtb DsbA, to Mtb DsbA.
Amino Acid Sequence ; Bacterial Proteins ; chemistry ; metabolism ; Catalytic Domain ; Crystallography, X-Ray ; Disulfides ; chemistry ; Escherichia coli ; metabolism ; Escherichia coli Proteins ; chemistry ; metabolism ; Molecular Docking Simulation ; Molecular Sequence Data ; Mycobacterium tuberculosis ; metabolism ; Oxidation-Reduction ; Protein Disulfide-Isomerases ; chemistry ; metabolism ; Protein Folding ; Protein Structure, Tertiary ; Sequence Alignment ; Static Electricity