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151.
Background
The association between methylenetetrahydrofolate reductase (MTHFR) 677C > T polymorphism and lung cancer risk has been studied in various populations with conflicting results. The aim of this study was to assess the association strength by a meta-analysis of published studies.Methods
We searched PubMed and Chinese Biomedical (CBM) databases for relevant literatures published by July 18, 2012. Pooled odds ratio (OR) with 95% confidence interval (CI) was calculated to assess the strength of the association.Results
A total of 20 studies comprising 11,653 cases and 12,032 controls were included in the final meta-analysis. Using the random effect model, we found that MTHFR 677TT variant genotype was associated with an increased lung cancer risk (OR = 1.26, 95% CI = 1.05–1.50, P = 0.011 for TT vs. CC; OR = 1.19, 95% CI = 1.03–1.37, P < 0.001 for TT vs. CC + CT; OR = 1.11, 95% CI = 1.02–1.22, P = 0.017 for T allele vs. C allele). In the further stratified analyses, the increased lung cancer risk was found in Asian subjects (OR = 1.31, 95% CI = 1.01–1.71, P = 0.045 for TT vs. CC; OR = 1.17, 95% CI = 1.00–1.38, P = 0.048 for TT vs. CC + CT). There were no evidences for obvious publication bias in the overall meta-analysis and Asian subjects.Conclusions
MTHFR 677TT genotype might increase the susceptibility of lung cancer, especially in Asians. 相似文献152.
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Purpose
Overexpression of proto-oncogene HER-2 is one of the main molecular markers of breast cancer involved in prognosis and diagnosis and also in trastuzumab therapy. Thus, a request for the evaluation of HER-2 status in breast cancer has been increasing. The aim of our study was assessment of HER-2 overexpression in malignant and benign breast cancer specimens by Real Time RT-PCR technique and comparison of its results with IHC outcomes.Methods
Twenty benign and sixty malignant breast cancers in addition to fifteen normal breast tissue specimens were analyzed by Real Time RT-PCR method. Fresh tissue samples were disrupted by mortar and pestle. A syringe and a needle were used for complete homogenization of the tissues. The RNA was then isolated from the samples and converted to cDNA. A standard curve was initially plotted using BioEasy SYBR Green I and then all 95 specimens were studied by Real Time RT-PCR using 2− ΔΔCt method.Results
23.3% of 60 malignant specimens showed HER-2 overexpression, while all of the benign samples represented the normal expression level of HER-2 gene. The concordance rate between the results of Real Time RT-PCR and IHC was 86.6%.Conclusion
Real Time RT-PCR method is an almost reliable technique and at least can be used as a complementary method for confirming IHC results. This is emanated from relatively high rate of concordance between outcomes of IHC test, as a routine method of detecting the HER-2 gene expression status, and Real Time RT-PCR technique. 相似文献155.
Liebenberg syndrome (MIM 186550) is a very rare autosomal dominant condition characterized by three main features: dysplasia of all of the bony components of the elbow joint, abnormalities in the shape of carpal bones, and brachydactyly. In this paper, we report a Saudi Arabian family with Liebenberg syndrome. Comparative genomic hybridization (CGH) revealed a 275-kb deletion within the cytogenetic band 5q31.1 which contains the H2AFY gene and 190,428 bp of its downstream region. The deleted region is upstream to the PITX1 gene. The radiological features in the upper limbs of all affected members of the family were almost identical to the phenotype in the mouse model with ectopic expression of Pitx1 in the forelimbs. We therefore re-define the phenotype of Liebenberg syndrome as a transformation of the upper limbs to reflect lower limb characteristics and speculate that the area of deletion contains a regulatory sequence that suppresses the expression of PITX1 in the upper limb buds. 相似文献
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Chih-Ping Chen Chen-Ju Lin Yi-Yung Chen Liang-Kai Wang Schu-Rern Chern Peih-Shan Wu Jun-Wei Su Li-Feng Chen Dai-Dyi Town Chen-Wen Pan Wayseen Wang 《Gene》2013
We present prenatal diagnosis and array comparative genomic hybridization characterization of 3q26.31–q29 duplication and 9q34.3 microdeletion in a fetus with omphalocele, ventricular septal defect, increased nuchal translucency, abnormal first-trimester maternal screening and facial dysmorphism with distinct features of the 3q duplication syndrome and Kleefstra syndrome. The 26.61-Mb duplication of 3q26.31–q29 encompasses EPHB3, CLDN1 and CLDN16, and the 972-kb deletion of 9q34.3 encompasses EHMT1. We review the literature of partial trisomy 3q associated with omphalocele and discuss the genotype–phenotype correlation in this case. 相似文献
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