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Objective:To study the mutation frequencies of the exon 5 and the exon 8 of PTEN (phosphatase and tensin homology deleted on chromosome ten) gene in gastric carcinoma and investigate the relationship of the gene mutation and pathological differentiation and clinical stage.Methods:The mutation of exon 5 and exon 8 of PTEN gene was detected in 42 gastric carcinoma samples and the matched adjacent normal gastric mucosa with polymerase chain reaction-single strand conformation polymorphism(PCR-SSCP) method.The PCR products of mutant samples were analysed by DNA sequencing technique.Results:The mutation of PTEN was shown in 3 of the 42 gastric carcinoma tissues and in none of the adjacent normal tissues.The mutation rates of PTEN gene in poorly differentiated and well differentiated samples were 12.00% and 0,respectively (P0.05).The mutation rates of PTEN gene in clinical stage Ⅰand Ⅱ (5.88%) had no significant difference with that in clinical stage Ⅲand Ⅳ (8.00%) (P0.05).Conclusion:PTEN gene mutation occurs mainly in poorly differentiated gastric carcinoma tissues,and the mutation rate is not related to pathological differentiation and clinical stage.
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Objective To explore the relationship of phosphatase and tensin homology (PTEN) deleted on chromosome ten with the apoptosis of hepatic stellate cells (HSCs) in liver tissues of rats with hepatic fibrosis induced by bile stagnation.Methods Fifty adult male SD rats were randomly divided into model group (n=40) and sham operation group (n=10).The model of hepatic fibrosis was reproduced in model group by common bile duct ligation (BDL).Liver tissue of rats in model group (1,2,3 and 4 weeks after BDL) and sham operation group were obtained.PTEN expression in liver tissue was detected by immunohistochemistry.Apoptosis of HSC was determined by dual staining of terminal deoxynucleotidy transferase UTP-nick end labeling (TUNEL) and ?-SMA immunohistochemistry.Results Only a few apoptotic HSCs were found in normal livers.With the development of liver fibrosis,the expression of PTEN decreased gradually (P
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Objective To investigate the role of PTEN protein in secretion of collagen Ⅳ and fibronectin after stimulation of transforming growth factor beta 1(TGF-?1) from renal fibroblasts of rat in vitro.Methods The cultured rat renal fibroblasts were transfected with the reconstructed adenovirus containing PTEN or adenovirus only containing green fluorescence protein(GFP).The fibroblsts were treated in four manners:control group with no added treatment,TGF-?1 group with TGF-?1 stimulation,PTEN+ TGF-?1 group with TGF-?1 stimulation after Ad-PTEN transfection,and GFP+ TGF-?1 group with TGF-?1 stimulation after Ad-GFP transfection.Invert fluorescent microscope was used to detect the GFP expression,meanwhile the PTEN mRNA was determined by RT-PCR method.36h after the transfection,TGF-?1 was added into the culture medium in a concentration of 10ng/ml.After another 24h,ELISA method was used to evaluate the level of collagen Ⅳ and fibronectin.Results The expressions of both GFP and PTEN mRNA increased obviously after the rats' renal fibroblasts were transfected with adenovirus.The secretion of collagen Ⅳ and fibronectin increased significantly in both TGF-?1 group and GFP+ TGF-?1 group compared with that in control group,and decreased markedly in PTEN+ TGF-?1 group compared with that in both TGF-?1 group and GFP+ TGF-?1 group(P
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Objective To investigate the expression of tumor suppressor gene PTEN in breast carcinomas and its significance. Methods Immunohistochemical method was used to detect the expression of PTEN gene in 146 cases of breast carcinoma and 10 specimens of normal breast tissue closely adjacent to carcinoma. Results It was showed that PTEN gene was expressed in all 10 specimens of breast tissue closely adjacent to carcinoma. Expression of PTEN was localized in cytoplasm and nuclei of epithelial cells of lobular acini and epithelial cells of ducts. The rate of PTEN expression was 57.5% (84/146) in breast carcinoma. Expression of PTEN was related to tumor size, pathological stage, and the expression of ER and PR of breast cancer. The 2-year disease free survival of PTEN high expression breast cancer patients was superior to those with low expression (P
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Objective To detect the mutation frequency and mutation type of tumor suppressor PTEN in sporadic breast carcinoma tissues, and to investigate the association of PTEN gene mutation and sporadic breast cancer. Methods Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to amplify 9 exons of PTEN and to analyze the conformation polymorphism, then DNA sequencing methods was used to detect point mutation of PTEN gene nine exons of abnormal single strand conformation in breast carcinoma. Results One of 45 cases showed 24th condon A→C missense mutation in the exon2 of PTEN gene, and this mutation made Met to change to Ala in PTEN protein structure. Conclusion These data indicated the existence of PTEN mutation in sporadic breast cancer, but PTEN gene mutation rate is very low.
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AIM: To study the prognositic value of PTEN and Her-2 expression in primary breast cancer.METHODS: 81 breast cancer specimens with 15 years follow-up were obtained from 1989 to 2004.Immunohistochemical methods were used to detect the expression of PTEN and Her-2 in 81 paraffin-embedded specimens.The correlation between expression of PTEN and clinipathological factors was discussed with the Chi-square test.The survival rate analysis results were calculated with Kaplan-meier method.Long-rank test and Cox model by SPSS 10.0 software.RESULTS:(1) PTEN expression significantly affects 5-year and 10-year survival rate of breast cancer(P