大骨节病儿童与成人外周血中基因表达水平的比较研究

A comparative study of gene expression level in peripheral blood mononuclear cells between children and adults patients with Kashin-Beck disease

目的对比分析大骨节病儿童与成人病例外周血中的差异表达基因，为确定大骨节病软骨损伤相关基因提供科学依据。方法收集18例大骨节病儿童（儿童病例组）、18例健康儿童（儿童对照组）的外周血样，按性别与年龄匹配后分为6组。收集21例大骨节病成人（成人病例组）、21例健康成人（成人对照组）的外周血样，按性别与年龄匹配后分为7组。每组均包含3名健康人与3名病例。提取血液总RNA，利用基因芯片技术检测4组儿童（24例）与5组成人（30例）的367个外周血基因差异表达，通过平均基因表达率（表达率≥2．0或≤0．5）分别确定大骨节病儿童组与大骨节病成人组的差异表达基因。并用实时荧光定量PCR（qRT-PCR）技术检测余下的2组儿童（12例）与2组成人（12例）血样中3个基因表达，验证芯片结果的可靠性。结果儿童病例组外周血检测到101个差异表达基因，占所测基因（367个）的27．5％，少于大骨节病成人病例组（159个，43．3％，χ2=20．036，P〈0．01）；儿童病例组与成人病例组共存57个差异表达基因，其中21个基因差异表达的方向不同。qRT-PCR验证结果与基因表达芯片结果一致。结论大骨节病儿童与成人外周血基因表达模式随关节软骨和运动功能损害的严重程度不同而不同。在儿童大骨节病发病中骨软骨发育相关基因的异常表达可能与儿童骺板软骨的损伤有关，其在大骨节病早期损害中的作用值得重视。

Objective To investigate and compare the differentially expressed genes of children and adults patients with Kashin-Beck disease （KBD） in peripheral blood mononuclear cells （PBMCs） so as to provide new clues to identify the genes related to cartilage lesion of KBD. Methods Eighteen KBD children and 18 healthy children were selected and divided into 6 matched groups according to age and gender. Twenty-one KBD adults and 21 healthy adults were selected and divided into 7 matched groups according to age and gender. Every group had 3 patients and 3 healthy persons. Peripheral blood samples were collected and total RNA was extracted respectively. The expression levels of 367 target genes in 4 child groups （24 subjects） and 5 adult groups （30 subjects） were evaluated using customized oligonucleotide microarray. Those genes with ≥2.0 or ≤0.5 expression ratio were regarded as differentially expressed genes. Quantitative real-time reverse transcription polymerase chain reaction （qRT-PCR） was conducted to validate the microarray data using the remaining 2 child groups （12 subjects） and 2 adult groups （12 subjects）. Results There detected 101 differentially expressed genes in KBD children, accounting for 27.5% of all 367 target genes. It was less than that in KBD adults （159, 43.3%, χ2 = 20.036, P 〈 0.01）. Fifty-seven differentially expressed genes were shared by KBD children and KBD adults but 21 of them were asynchronously expressed in KBD children compared to KBD adults. The result of qRT-PCR experiment was consistent with that of the microarray study. Conclusions There are significant differences in gene expression pattern between KBD children and KBD adults relating to the severity of articular cartilage and motor function damages. Bone-development related genes may play an important role in epiphyseal plate lesion of KBD children and we should pay more attention to its role in the early stage of KBD.