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21.
AIM:To investigate the effects of exogenously mutated p27^kip1 (p27) on proliferation and apoptosis of human cholangiocarcinoma cell line, QBC939 in vivo.METHODS: Adenviral vectors were used to transfect mutated p27 cDNA into human QBC939 cell line. Expression of p27 was detected by RT-PCR. Western blot. Cell growth, morphological change, cell cycle, apoptosis and cloning formation were determined by MTT assay and flow cytometry.RESULTS: The expression of p27 protein and mRNA was increased signifi cantly in QBC939 cell line transfected with Ad-p27mt. The transfer of Ad-p27mt could signifi cantly inhibit the growth of QBC939 cells, decrease the cloning formation rate and induce apoptosis. p27 over expression caused cell cycle arrest at G0/G1 phase 72 h after infection with Ad-p27mt.CONCLUSION: p27 may cause cell cycle arrest at G0/G1 phase and subsequently lead to apoptosis. Recombinant adenovirus expressing mutant p27 may be potentially useful in gene therapy for cholangiocarcinoma.  相似文献   
22.
AIM: To determine allelic imbalance on chromosomal region 21q22-qter including trefoil factor family genes (TFF) in cholangiocarcinoma (CCA) patients and analyze the correlation between allelic imbalances and clinicopathological parameters.METHODS: Quantitative PCR amplification was performed on four microsatellite markers and trefoil factor family genes (TFF1, TFF2, and TFF3) using a standard curve and SYBR Green Ⅰ dye method. The relative copy number was determined by DNA copy number of tested locus to reference locus. The relative copy number was interpreted as deletion or amplification by comparison with normal reference range. Associations between allelic imbalance and clinicopathological parameters of CCA patients were evaluated by x2-tests.Kaplan-Meier method was used to analyze survival.RESULTS: The frequencies of amplification at D21S1890,D21S1893, and TFF3 were 32.5%, 30.0%, and 28.7%,respectively. Patients who had amplification at regions covering D21S1893, D21S1890, and TFF showed poor prognosis, whereas patients who had deletion showed favorable prognosis (mean: 51.7 wk vs 124.82 wk,P = 0.012). Multivariate Cox regression analysis revealed that amplification of D21S1893, D21S1890 and TFF,blood vessel invasion, and staging were associated with poor prognosis.CONCLUSION: D21S1893-D21S1890 region may harbor candidate genes especially TFF and serine protease family, which might be involved in tumor invasion and metastasis contributing to poor survival. The amplification in this region may be used as a prognostic marker in the treatment of CCA patients.  相似文献   
23.
胆管癌并阻塞性黄疸的影像学诊断及介入治疗现状与进展   总被引:1,自引:0,他引:1  
影像学检查是临床诊断胆管癌的主要方法,但不同方法各具特点,合理选择影像学检查途径有助于提高诊断率.随着影像学技术的发展,胆管癌的影像学诊断取得了一定进展.介入治疗为中晚期胆管癌患者提供了有效的治疗措施,但因治疗方法较多,尚需规范,亟需深入研究,建立科学的介入治疗模式.  相似文献   
24.
AIM: To explore the effect of histone deacetylase inhibitor, trichostatin A (TSA) on the growth of biliary tract cancer cell lines (gallbladder carcinoma cell line and cholangiocarcinoma cell line) in vivo and in vitro, and to investigate the perspective of histone deacetylase inhibitor in its clinical application. METHODS: The survival rates of gallbladder carcinoma cell line (Mz-ChA-l cell line) and cholangiocarcinoma cell lines (QBC939, KMBC and OZ cell lines) treated with various doses of TSA were detected by methylthiazoy tetrazolium (MTT) assay. A nude mouse model of transplanted gallbladder carcinoma (Mz-ChA-l cell line) was successfully established, and changes in the growth of transplanted tumor after treated with TSA were measured. RESULTS: TSA could inhibit the proliferation of gallbladder carcinoma cell line (Mz-ChA-l cell line) and cholangiocarcinoma cell lines (QBC939, KMBC and OZ cell lines) in a dose-dependent manner. After the nude mouse model of transplanted gallbladder carcinoma (Mz- ChA-l cell line) was successfully established, the growth of cancer was inhibited in the model after treated with TSA. CONCLUSION: TSA can inhibit the growth of cholangiocarcinoma and gallbladder carcinoma cell lines in vitro and in vivo.  相似文献   
25.

Background

Cholangiocarcinoma (CCA) represents a devastating malignancy characterized by high mortality, and notoriously problematic to diagnose. Recently, microRNAs (miRs) have been intensively investigated due to their potential usefulness from a tumor treatment perspective.

Aims

The current study was aimed to investigate whether miR-494 influences epithelial-mesenchymal transition (EMT), tumor growth and metastasis of CCA.

Methods

The regulatory miRNAs of WDHD1 in CCA expression chip were predicted, followed by determination of the miR-494 and WDHD1 expression in normal cholangiocyte tissues and CCA tissues. The related protein levels were determined. CCA cell migration, invasion, viability, and cell cycle distribution and the dosage-dependent effect of miR-494 on CCA cell growth were subsequently detected. Finally, tumorigenicity and lymph node metastasis (LNM) were measured.

Results

Initially, miR-194 affected the CCA development via negatively regulating WDHD1 and miR-494 which were downregulated while WDHD1 was upregulated in CCA. In addition, miR-494 overexpression elevated E-cadherin expression while decreased expressions of WDHD1, N-cadherin, Vimentin, Snail, Twist and MMP-9. Finally, overexpressed miR-494 was observed to suppress EMT, cell viability, migration, invasion, arrest cell cycle progression, tumor formation, and LNM while accelerating cell apoptosis in vivo.

Conclusion

This study indicated that miR-494 overexpression suppresses EMT, tumor formation and LNM while promoting CCA cell apoptosis through inhibiting WDHD1 in CCA.  相似文献   
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The use of liver magnetic resonance imaging is increasing thanks to its multiparametric sequences that allow a better tissue characterization, and the use of hepatobiliary contrast agents. This review aims to evaluate gadoxetic acid enhanced magnetic resonance imaging in the diagnosis and staging of cholangiocarcinoma and its different clinical and radiological classifications proposed in the literature. We also analyze the epidemiology, risk factors in correlation with clinical findings and laboratory data.  相似文献   
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