OBJECTIVETo construct a recombinant adenovirus vector for SH2-DED fusion gene and assess its inhibitory effect on the proliferation of K562 cells.

METHODSSH2-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.

RESULTSThe 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).

CONCLUSIONThe recombinant adenovirus vector Ad5F35-SD-EGFP we constructed can significantly inhibit the proliferation of K562 cells in vitro.

Adenoviridae ; genetics ; metabolism ; Apoptosis Regulatory Proteins ; biosynthesis ; genetics ; Cell Proliferation ; drug effects ; Cloning, Molecular ; Genetic Vectors ; Green Fluorescent Proteins ; biosynthesis ; genetics ; Humans ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; pathology ; Mutant Proteins ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; Repressor Proteins ; biosynthesis ; genetics ; Shc Signaling Adaptor Proteins ; biosynthesis ; genetics ; Transfection

Adolescent ; Adult ; Female ; Fusion Proteins, bcr-abl ; genetics ; Gene Expression ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; genetics ; Leukemia, Myeloid ; genetics ; Male ; Oncogene Proteins, Fusion ; genetics ; Retrospective Studies

PURPOSE: It has been reported that the antibody against p53 is detected in a certain proportion of patients with malignancies. The authors designed this study to investigate the correlation between appea rance of the serum p53 antibody and tissue expression of the mutant p53 protein in primary breast carcinomas. METHODS: We conducted assays for the serum p53 antibody in 76 patients with primary breast cancer by using a sandwich enzyme linked immunosorbent assay (ELISA). Immunohistochemical assays for tissue expression of the p53 mutant protein were also undertaken in the same patients, and the results were analyzed according to the patients' outcomes and the clinical/histopathologic parameters. RESULTS: Antibody against p53 was detected as a high titer in the sera of 12 patients (16.9%) whereas the mutant p53 protein was detected in 41.1% of the breast cancer tissues. We found a significant correlation between serum p53 antibody status and tissue expression of the mutant p53 protein (p=0.019), whereas serum p53 antibody status did not correlate with any clinical/histopathologic parameters except the histologic grade of the tumors. The antibody against the p53 protein was more frequently detected in the patients with undifferentiated tumors. In the survival analysis, the serum p53 antibody had no significant correlation with recurrence of the disease or with patient survival. CONCLUSION: It seems likely that accumulation of p53 protein in tumor cells may induce an immune response with the appearance of p53 antibodies in the sera of cancer patients. However, serum p53 antibody status failed to discriminate high risk population of breast cancer patients.
Antibodies ; Breast Neoplasms* ; Breast* ; Enzyme-Linked Immunosorbent Assay ; Humans ; Mutant Proteins ; Prognosis ; Recurrence

BACKGROUND: Recently, VE1, a monoclonal antibody against the BRAFV600E mutant protein, has been investigated in terms of its detection of the BRAFV600E mutation. Although VE1 immunostaining and molecular methods used to assess papillary thyroid carcinoma in surgical specimens are in good agreement, evaluation of VE1 in thyroid cytology samples is rarely performed, and its diagnostic value in cytology has not been well established. In present study, we explored VE1 immunoexpression in cytology samples from ex vivo papillary thyroid carcinoma specimens in order to minimize limitations of low cellularity and sampling/targeting errors originated from thyroid fineneedle aspiration and compared our results with those obtained using the corresponding papillary thyroid carcinoma tissues. METHODS: The VE1 antibody was evaluated in 21 cases of thyroid cytology obtained directly from ex vivo thyroid specimens. VE1 immunostaining was performed using liquid-based cytology, and the results were compared with those obtained using the corresponding tissues. RESULTS: Of 21 cases, 19 classic papillary thyroid carcinomas had BRAFV600E mutations, whereas two follicular variants expressed wild-type BRAF. VE1 immunoexpression varied according to specimen type. In detection of the BRAFV600E mutation, VE1 immunostaining of the surgical specimen exhibited 100% sensitivity and 100% specificity, whereas VE1 immunostaining of the cytology specimen exhibited only 94.7% sensitivity and 0% specificity. CONCLUSIONS: Our data suggest that VE1 immunostaining of a cytology specimen is less specific than that of a surgical specimen for detection of the BRAFV600E mutation, and that VE1 immunostaining of a cytology specimen should be further evaluated and optimized for clinical use.
Biopsy, Fine-Needle ; Immunohistochemistry ; Mutant Proteins ; Sensitivity and Specificity ; Thyroid Gland* ; Thyroid Neoplasms*

BACKGROUND: Mutations in Cu, Zn-superoxide dismutase (SOD1) cause about 20% of familial amyotrophic lateral sclerosis (FALS) cases. The mechanism of late-onset disease manifestation despite the innate mutation has no clear explanation. The relationship between homocysteine (HC) and amyotrophic lateral sclerosis (ALS) has not been investigated fully, in spite of the similarity in their pathogenesis. METHODS: We investigated the effect of HC on the motor neuronal cell-line (VSC4.1) transfected with SOD1 of either wild-type or mutant forms (G93A and A4V) using various methods including the MTT assay for the cytotoxic assay, the immunocytochemical staining using anti-SOD1 for the aggregation of SOD1, the western blotting using anti-nitrotyrosine and anti-DNPH for the oxidative protein damage, and the measurement of the intracellular Ca2+ concentration using Fura2-AM. RESULTS: In the MTT assay, the HC induced significant cytotoxicity in the mutants, as compared with wild-type. This HC-induced cytotoxicity was inhibited by the trolox and the bathocuproinedisulfonate (BC). HC increased the carbonylation and nitrosylation of the mutant proteins. HC also increased significant SOD1-aggregation in mutants. This HC-induced SOD1-aggregation in mutants was inhibited by trolox, N-nitro-L-arginine methyl ester, BC, and z-VAD-FMK. HC did not change the intracellular concentration of Ca2+ in the mutants compared with the wild-type. CONCLUSIONS: The authors showed that the vulnerability of the SOD1 mutant motor neuronal cells to HC involves the copper-mediated oxygen radical toxicity, and that HC may be a lifelong precipitating factor in some forms of FALS, suggesting a possible treatment modality with vitamin supplements.
Amyotrophic Lateral Sclerosis ; Blotting, Western ; Homocysteine* ; Motor Neurons* ; Mutant Proteins ; Oxygen ; Precipitating Factors ; Vitamins

Although bladder cancers are very common, little is known about their molecular pathogenesis. It is known, that p53 alteration is found in about 60%p of muscleinvasive bladder cancer, necessiating aggressive therapy and poor outcome. We examined the nuclear expression of p53 protein, using D07 monoclonal antibody in the urine samples, from 31 patients with transitional cell carcinoma of the bladder to investigate the correlation of p53 overexpression with histologic grades and depth of invasion. The positive rate of p53 protein was 27%o in superficial bladder tumor, but increased up to 71% in the invasive bladder carcinomas. The overexpression of p53 protein increased according to Mostofi grading system from 18% in grade I, 45% in grade Il, and up to 100% in grade ill. The p53 expression tended to be higher in the invasive and high grade bladder cancers than in the superficial and low grade ones(p<0.05). These results suggest that immunohistochemical analysis of the urine specimen in the bladder cancer patients could be a useful method of screening for the presence of p53 mutant protein. The mutant p53 protein expression may be an indicator of bladder cancer with more proliferative potential and/or aggressive biologic behavior.
Carcinoma, Transitional Cell ; Genes, p53* ; Humans ; Immunohistochemistry ; Mass Screening ; Mutant Proteins ; Urinary Bladder Neoplasms* ; Urinary Bladder*

In patients who have sustained traumatic brain injury with associated extremity fracture, there is often a clinical perception that the rate of new bone formation around the fracture site increases.(1) An overgrowth of callus is observed and ectopic ossification even occurs in the muscle,(2) but the mechanism remains unclear. Whether this rapidly-formed new bone is fracture callus or a variant of heterotopic ossification, a common complication of traumatic brain injury, is the subject of some debates.(3) It is generally believed that the process of fracture healing is a recapitulation of normal embryonic osteogenesis,(4) i.e. ,a series of changes in the intracellular and extracellular matrix, which start from the injury of cells, blood vessels and bone matrix to a complete reconstruction of the bone.(5) It is a complex process influenced by multi-level and multi-route regulations of the general and local environments in the body, and many growth factors participate in this process, which is the base of bone healing;(6) whatever methods are used to promote bone healing, they are based on accelerating the changes of growth factors.(7) So it is worth making a thorough study on the mechanism, by which traumatic brain injury influences the expression levels of growth factors and consequently affects the speed of bone healing.
Animals ; Brain ; metabolism ; Brain Injuries ; physiopathology ; Fibroblast Growth Factor 2 ; physiology ; Fracture Healing ; Gene Expression ; physiology ; Humans ; Oncogene Protein p65(gag-jun) ; metabolism ; Oncogene Proteins v-fos ; metabolism ; Vascular Endothelial Growth Factor A ; physiology

To investigate the mechanism of high product specificity of gamma-clodextrin glucanotransferase (CGTase) from alkalophilic Bacillus clarkii 7364, we aligned protein sequence and structure model, found out that loss of 6 amino acids at subsite -7 probably affected its product specificity. Using overlapping PCR method, we inserted 6 amino acids into subsite -7 of CGTase. The mutant CGTase gene was ligated with pET-20b (+) and expressed in Escherichia coli BL21 (DE3). The extracellular recombinant enzyme was used to transform soluble starch into cyclodextrins (CDs). HPLC analysis results show that, compared to wild CGTase, the gamma-CDs produced by mutant enzyme decreased from 76.0% to 12.5%, whereas the ratio of alpha- and beta-CDs increased from 8.7% and 15.2% to 37.5% and 50%. The possible mechanism was that, compared to alpha-, beta-CGTase, wild gamma-CGTase lacks 6 amino acids in its subsite -7. This conformation provided more space for glucose combination and was thus advantageous for forming gamma-CD. When the 6 amino acids were inserted into the subsite -7 of wild gamma-CGTase, the space to bind with glucose reduced and consequently resulted in less gamma-CD production.
Bacillus ; enzymology ; genetics ; Escherichia coli ; genetics ; metabolism ; Glucosyltransferases ; biosynthesis ; genetics ; Mutant Proteins ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics

Apolipoprotein A-I-Milano(AIM), a natural variant, not only inhibits the initiation and progression of atherosclerosis, but also makes the preexisting atherosclerotic lesions regress. AIM gene, at which N-terminal codens were optimized, was subcloned into the expression vector of pET22b. Recombiant plasmids were transformed into E. coli strain BL21 (DE3) and induced with IPTG. The expressed apoliprotein A-I-Milano was soluble in E. coli and was about 38% of total cell lysate. Purified by Butyl Sepharose 4F. F hydrophobic chromatography and Q Sepharose H.P. anion exchange chromatography, followed by ultrafiltration with Vivaspin 20 (30 000MW), AIM monomer was obtained in a purity of more than 95%. Activity assay of binding of AIM monomer to lipid indicates that association of AIM monomer with DMPC is slower than normal apoA-I but DMPC number associated by AIM monomer is more than by apoA-I. This results will be important for studying structure, function of AIM, specially clinical application.
Apolipoprotein A-I ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Humans ; Mutant Proteins ; biosynthesis ; genetics ; Recombinant Proteins ; biosynthesis ; genetics ; Solubility

Autophagy is a highly regulated cellular mechanism that results in the bulk degradation of long-lived proteins and organelles and which seems to be implicated in a variety of physiological and pathological conditions relevant to neurological diseases. The formation of intraneuronal mutant protein aggregates is a characteristic of several human neurodegenerative disorders such as Alzheimer's disease and Parkinson's disease, and polyglutamine disorders such as Huntington's disease (HD). Autophagy is a major clearance pathway for the removal of the mutant huntingtin protein associated with HD, and many other disease-causing, cytoplasmic, aggregate-prone proteins. Autophagy is negatively regulated by the mammalian target of rapamycin (mTOR) and can be induced in all mammalian cell types by the mTOR inhibitor rapamycin. It can also be induced by an mTOR-independent pathway, which has multiple drug targets, involving links between Ca2+-calpain-Gsa and cAMP-Epac-PLC-e-IP3 signaling. Both pathways enhance the process of autophagy. In this review, we describe the various drugs and pathways that induce autophagy that are potential therapeutic approaches for neurodegenerative disorders.
Alzheimer Disease ; Autophagy ; Cytoplasm ; Humans ; Huntington Disease ; Mutant Proteins ; Neurodegenerative Diseases ; Organelles ; Parkinson Disease ; Peptides ; Proteins ; Sirolimus