高氧致早产儿支气管肺发育不良与SOX基因的关联及其作用机制

Bronchopulmonary dysplasia (BPD) is a common respiratory disease in premature infants, which is associated with genes and environmental factors.Hyperoxia is an important factor of BPD, but the mechanism is unknown.SRY-related HMG-box (SOX) gene is a family coding transcription factor,which participates in various kinds of the early embryonic development, is an negative regulatory factor which controls Wnt signal transduction pathway in cell nucleus.In view of the research in the relationship between Wnt signal transduction pathway and development of lung, and the relationship between the expressing of SOX gene and diseases,it is reasonable to predict that the Changes in function of SOX gene may be an important factor which is responsible for hyperoxia-induced BPD.The role and pathogenesis of SOX gene in BPD has not been reported.This research analyzes the association between single nucleotide polymorphism (SNP) of SOX gene and BPD susceptibility in premature infants with case-control study design,and analyzes the biological function of SOX gene in SNP through techniques of gene transfection and gene silencing with cell model and animal model;meanwhile studies the expression and Clinical Significance of SOX gene in lung tissues of premature rats induced by Hyperoxia,and preliminary investigates the effects of overexpression or silencing of SOX gene on the migratory ability,invasive ability and reproductive activity of type Ⅱ penumonocyte,so as to provide new clues to search molecular markers and treatment targets in Hyperoxia-induced BPD early diagnosis from a new perspective.

支气管肺发育不良(BPD)是早产儿呼吸系统常见疾病,是环境和遗传因素共同作用的结果。高氧是BPD发生的重要因素，但其致病的确切机制仍未阐明。SOX基因是一类编码转录因子基因家族，是细胞核内Wnt信号通路的负性调控因子，参与多种早期胚胎发育过程。借助Wnt信号通路与肺部发育的关系及SOX基因表达与疾病相关性研究成果,有理由推测SOX基因功能改变可能是引起高氧致BPD的重要因素，而迄今有关SOX基因在BPD的作用及发病机制尚未见报道。本研究运用病例对照研究设计分析SOX基因多态性与早产儿BPD易感性的关联，利用细胞模型和动物模型，通过基因转染、沉默等研究方法，分析SOX基因SNP的生物学功能；研究SOX基因在高氧致早产鼠肺组织中的表达及意义，初步探讨过表达或沉默SOX基因对肺泡Ⅱ型上皮细胞迁徙能力、侵袭能力及增殖能力的影响，为从新的角度寻找高氧致BPD早期诊断的分子标志物及治疗靶标提供新线索。

支气管肺发育不良(BPD)是早产儿呼吸系统常见疾病,是环境和遗传因素共同作用的结果。高氧是BPD发生的重要因素。SOX基因是一类编码转录因子基因家族，是细胞核内Wnt信号通路的负性调控因子，参与多种早期胚胎发育过程。本课题组通过建立高氧暴露大鼠肺损伤模型、临床病例对照研究SOX基因多态性与早产儿BPD易感性的关联，筛选出目标基因SOX4，通过SOX4基因的沉默对高氧暴露原代培养的II型肺泡上皮细胞（AEC II）增殖及迁移的影响及其分子机制，以寻找(BPD早期诊断的分子标志物及治疗靶标。主要成果如下：.一、动物模型研究显示SOX4及SOX9可能是参与早期高氧肺损伤的两个关键基因。.二、研究了107例早产儿BPD病例和242例早产儿非BPD病例SOX基因rs9368326（SOX4）、rs1042667（sox9）、rs12234941（sox17）多肽性及环境因素与BPD遗传易感性的关系，筛选出SOX4基因为靶基因：.①sox9点突变的C等位基因的AC/CC突变型可增加早产儿患BPD的风险；②sox4位点与胎龄存在交互作用，其交互作用可降低早产儿BPD发病风险。③sox9、sox4和sox17三个位点与宫内感染、吸氧均存在交互作用，其交互作用可增加早产儿BPD发病风险。④低胎龄、宫内感染、吸氧是早产儿发生BPD的危险因素⑤sox9、sox4和sox17与低胎龄、宫内感染、吸氧等环境危险因素可能存在基因-环境交互作用。.三、通过SOX4基因的沉默用荧光染色、平板集落形成、流式细胞术、划痕试验、western blot试验、Real-Time PCR对高氧暴露原代培养的II型肺泡上皮细胞（AEC II）的增殖及迁移的及分子机制进行了研究:. 1.SOX4沉默可显著抑制75%氧暴露诱导的 AEC II的增殖和迁移能力、G0/G1期比例（p < 0.01）显著减少、G2/M期细胞显著增加，提示SOX4参与了高氧暴露AEC II增殖和迁移调控。 .2．①SOX4沉默可显著抑制氧诱导的 AEC II的β-catenin的核移位及Cyclin D1, TGFβ-1, c-Myc, SPC, α-SMA, USP-7和SETD6的表达增加；说明①SOX4通过WNT信号通路调节AEC II的增殖和迁移；②SOX4可能通过去泛素化酶途经调控β-catenin。.四、目前已收录的论文3篇