Hedgehog-GLI信号通路在胰腺癌发生中的作用

近年来研究发现Hedgehog-GLI信号转导通路的异常激活参予胰腺癌的发生及恶性生物学特性的维持.GLI锌指转录因子作为该信号通路末端的靶基因直接调控子,在这一过程中起着非常重要的作用.本文就Hedgehog-GLI信号通路在胰腺癌发生中的作用、GLI转录活性的调控及致瘤作用、Hedgehog-GLI通路的靶向治疗价值等方面的研究进展作一综述.     

动脉平滑肌细胞一氧化氮合酶与高血压发病的关系

目的 探讨高血压病患者血管平滑肌细胞（ＶＳＭＣ）一氧化氮合酶（ＮＯＳ）活性和ＮＯＳ基因表达的特点及其与高血压发病的关系。方法 采用复合胶原酶法分离培养高血压病患者和血压正常者动脉ＶＳＭＣ,并以血红蛋白分光光度法、原位反转录聚合酶链反应检测ＶＳＭＣ的ＮＯＳ活性和诱生型ＮＯＳ（ｉＮＯＳ）ｍＲＮＡ表达量。结果 （１）高血压组ＶＳＭＣ的ＮＯＳ活性和ｉＮＯＳ ｍＲＮＡ表达量均显著低于正常组（Ｐ〈０．０１）;     

小鼠白细胞介素23基因在毕赤酵母中的诱导表达及初步活性研究

目的:克隆小鼠白细胞介素23(mice interlecukin-23,mIL-23)基因,构建高效稳定的毕赤酵母表达菌株,并对得到的蛋白进行生物活性的初步测定。方法:采用聚合酶链式反应(PCR)技术从pcDNA3-mIL-23上分别扩增获得IL-23的两亚基p19和p40,并通过重叠PCR(over-lap PCR)技术获得含有连接子的p1940,构建pPICZαA-IL-23重组质粒;采用甲醇诱导毕赤酵母表达重组蛋白,MTT方法检测诱导表达蛋白的促淋巴细胞增殖情况。结果:SDS-PAGE分析显示在诱导24小时和36小时后的上清及24～96小时的沉淀中均可以检测到约70 kD的诱导条带。Western blot印迹法证实了重组蛋白为特异性蛋白。上清和沉淀中表达的重组蛋白IL-23能促进外周血单个核细胞的增殖,OD570 nm分别达到(0.235±0.029)和(0.216±0.035),而未刺激的对照组只有(0.135±0.008)和(0.164±0.017)。结论:成功构建出mIL-23的酵母表达载体,诱导产生的蛋白可以明显地促进外周血单个核细胞的增殖。     

诱导多能性干细胞研究进展

人类诱导多能性干细胞（iPS细胞）的出现被誉为生命科学领域里新的里程碑,它建立了一种全新的、相对易操作而较稳定的体细胞核重编程方法,在生物学基础研究和临床应用方面具有潜在的价值;然而,iPS细胞的高癌变率和极低的重编程效率大大限制了它的应用。目前iPS细胞技术正在被不断完善,就iPS细胞的研究历程及在诱导iPS细胞上的最新研究进展进行综述。     

αβ复合型地中海贫血的分子检测及血液学分析

目的通过对αβ复合型地中海贫血的分子基因型的检测及血液学的表型分析,了解其基因分布状况及发生率。方法采用单管多重缺口-PCR法和反向膜杂交法,对396例地中海贫血筛查阳性的样本进行α地中海贫血和β地中海贫血的基因诊断。结果在396例样本中,检出单纯性α地中海贫血109例(27.5%),单纯性β地中海贫血115例(29.0%),αβ复合型地中海贫血26例(6.57%)。αβ复合型地中海贫血占β地中海贫血的18.44%。αβ复合型地中海贫血共有7种基因型,涉及5种β地中海贫血突变类型(CD41-42、IVS-2-654、TA;TA;box-28、CD71-72、43)和2种α地中海贫血缺失类型(α地中海贫血-1基因和α地中海贫血-2基因)。红细胞参数(MCV、MCH及Hb)在αβ复合型地中海贫血与单纯性β-地中海贫血之间的差异不具有统计学意义(P>0.05)。结论αβ复合型地中海贫血双重杂合子的发生率较高,且缺乏特异性的血液学指标。对β地中海贫血筛查阳性的病人应同时进行α和β地中海贫血基因诊断,以减少αβ复合型地中海贫血漏检的可能,以便下一步正确地指导遗传咨询和产前诊断。     

Diagnostic value of RASSF1A hypermethylation in colorectal cancer: a meta-analysis

Purpose

Ras association domain family 1 isoform A (RASSF1A), a member of Ras association domain family, plays an important role in tumorigenesis. The goal of our meta-analysis was to assess the diagnostic value of RASSF1A hypermethylation in colorectal cancer (CRC).

RNA-Seq analysis in an avian model of maternal phenylketonuria

Cardiac malformations (CVMs) are a leading cause of infant morbidity and mortality. CVMs are particularly prevalent when the developing fetus is exposed to high levels of phenylalanine in-utero in mothers with Phenylketonuria. Yet, elucidating the underlying molecular mechanism leading to CVMs has proven difficult. In this study we used RNA-Seq to investigate an avian model of MPKU and establish differential gene expression (DEG) characteristics of the early developmental stages HH10, 12, and 14. In total, we identified 633 significantly differentially expressed genes across stages HH10, 12, and 14. As expected, functional annotation of significant DEGs identified associations seen in clinical phenotypes of MPKU including CVMs, congenital heart defects, craniofacial anomalies, central nervous system defects, and growth anomalies. Additionally, there was an overrepresentation of genes involved in cardiac muscle contraction, adrenergic signaling in cardiomyocytes, migration, proliferation, metabolism, and cell survival. Strikingly, we identified significant changes in expression with multiple genes involved in Retinoic Acid (RA) metabolism and downstream targets. Using qRTPCR, we validated these findings and identified a total of 42 genes within the RA pathway that are differentially expressed. Here, we report the first elucidation of the molecular mechanisms of cardiovascular malformations in MPKU conducted at early developmental timepoints. We provide evidence suggesting a link between PHE exposure and the alteration of RA pathway. These results are promising and offer novel findings associated with congenital heart defects in MPKU.     

Association between vascular endothelial growth factor gene polymorphisms and age-related macular degeneration in a Polish population

The pathogenesis of age-related macular degeneration (AMD) is thought to be determined by an array of environmental and genetic factors. The association of increased expression of vascular endothelial growth factor (VEGF) with AMD, especially the wet form of AMD, was reported in several studies. The VEGF gene is highly polymorphic and some of its polymorphisms may affect its expression. In our work, we searched for an association between the −460C> (rs833061) and −634G>C (rs2010963) polymorphisms of the VEGF gene and the occurrence of AMD and its dry and wet forms. We have chosen these polymorphisms because they were shown to be significant in other studies and we previously showed their association with diabetic retinopathy. A total of 401 individuals were enrolled in this study: 136 controls, and 88 patients with dry and 177 with wet AMD. The polymorphisms were determined with DNA from peripheral blood lymphocytes by allele-specific and restriction fragment length polymorphism polymerase chain reaction. The significance of the polymorphisms was assessed by multiple logistic regression, producing odds ratios (ORs) and 95% confidence intervals (CIs). We observed a weak association (OR 2.90) between AMD occurrence and the C/T genotype of the −460C>T polymorphism. An association (OR 3.77) between the C/T genotype of the −460C>T polymorphism and the occurrence of dry AMD was observed. The T/T genotype considerably lowered the risk of dry AMD (OR 0.19). Dry AMD was associated with the C/C genotype of the −634G>C polymorphism (OR 3.68). Another weak association (OR 2.63) was found between the C/T genotype of the −460C>T polymorphism and the occurrence of wet AMD. The occurrence of AMD was correlated with the presence of the combined C/T–G/G genotype of both polymorphisms (OR 2.41), whereas the T/T–G/G and T/T–G/C genotypes exerted a protective effect against the disease (OR 0.22 and 0.48, respectively). The presence of the C/T–G/G and C/T–C/C combined genotypes increased the risk of dry AMD (OR 2.08 and 3.77, respectively), whereas the presence of the T/T–G/G and T/T–G/C genotypes decreased the risk (OR 0.15 and 0.28, respectively). In the wet form of AMD, the combined genotype C/T–G/G slightly favored the disease (OR 2.61) and the T/T–G/G genotype had a protective effect (OR 0.25). Analysis of haplotypes of both polymorphisms yielded similar results for AMD in general as well as for the dry and wet forms of the disease: the CG haplotype favored both forms of AMD, whereas the TG haplotype protected against both forms of AMD. The results obtained indicate that the −460C>T and −634G>C polymorphisms of the VEGF gene may be associated with the dry and wet forms of AMD in a Polish population.     

基因打靶技术在构建人源体细胞基因敲除或敲入细胞系中的应用

基因打靶技术能够帮助人们认识某些动物个体或细胞表型异常的遗传基础，利用该技术构建的模式生物（例如基因敲除小鼠）已经广泛地应用于人类基因的研究，截至1999年就已经报道了800多个模式小鼠种系。同源重组介导的基因打靶技术（基因敲除或敲入）是判定基因功能的强有力工具。与基因敲除小鼠相比，人类体细胞基因敲除或敲入细胞系构建的报道相对较少，但该项技术在细胞水平上对某些人源基因参与的生化或生理途径的分析是不可替代的。基因打靶技术最常见的应用是通过使所有等位基因连续失活建立基因敲除细胞系；     

反义寡核苷酸抑制神经母细胞瘤LA-N-5细胞血管内皮生长因子mRNA表达及其生物效应的研究

目的研究血管内皮生长因子(VEGF)反义寡核苷酸(ASODN)转染对神经母细胞瘤LA-N-5细胞VEGF mRNA表达的影响以及对肿瘤细胞增殖、分化的影响。方法用LipofectamineTM2000介导的VEGF ASODN和错义寡核苷酸(MSODN)转染LA-N-5细胞,半定量RT-PCR检测各组细胞VEGF165和VEGF121 mRNA转染前后不同时间表达的变化;MTT法测定转染后各组细胞的生长曲线及抑制率。结果半定量RT-PCR检测结果显示,在转染后72 h VEGF165和VEGF121 mRNA的表达:ASODN组为0.346±0.029和0.227±0.036,ASODN+LipofectamineTM2000组为0.275±0.035和0.165±0.017。ASODN组和ASODN+LipofectamineTM2000组均显著抑制VEGF mRNA的表达,ASODN+LipofectamineTM2000组抑制作用较ASODN组更强(P<0.05);转染后ASODN组和ASODN+LipofectamineTM2000组细胞增殖显著受抑,在48 h时抑制率最高,分别为(39.92±2.7...