【摘要】：目的:micro RNA-495(mi R-495)在不同腫瘤中可發(fā)揮抑癌或致癌的作用,mi R-495的表達(dá)水平與啟動子區(qū)CPG島甲基化的程度有相關(guān)性。兒童ALL中尚未見相關(guān)研究。本研究旨在通過檢測分析ALL中mi R-495表達(dá)水平及甲基化狀態(tài)的差異,探討mi R-495在兒童ALL發(fā)病中的意義,了解其表達(dá)水平及甲基化狀態(tài)與ALLT/B分型、TEL/AML1等融合基因及誘導(dǎo)緩解療效的關(guān)系。方法:收集80例非超二倍體初發(fā)ALL患兒骨髓(bone marrow,BM)和外周血作為實驗組,10例免疫性血小板減少性紫癜(immune thrombocytopenia,ITP)兒童骨髓以及31例健康兒童外周血作為對照。提取ALL和ITP及正常人外周血DNA和RNA。對DNA進(jìn)行重亞硫酸鹽處理,對mi RNA進(jìn)行逆轉(zhuǎn)錄處理。采用甲基化敏感性高分辨率溶解曲線分析(methylation sensitivity of high resolution melting curve analysis,MS-HRM)方法對mi R-495基因啟動子區(qū)CPG島甲基化水平進(jìn)行檢測;實時熒光定量PCR方法對mi R-495表達(dá)水平進(jìn)行檢測。結(jié)果:1.mi R-495在ALL組表達(dá)水平為1.2800E-4(8.5450E-6,1.5450E-3),顯著低于ITP組[9.9500E-2(4.7963E-2,1.4302E-1)]及正常對照組[1.4800E-3(6.1050E-4,4.0850E-3)](P值均≤0.05)。2.ALL中mi R-495高表達(dá)組36例,其中B-ALL 35例,T-ALL 1例;低表達(dá)組44例,其中B-ALL33例,T-ALL 11例,mi R-495高表達(dá)組與低表達(dá)組之間B/T構(gòu)成比差異有統(tǒng)計學(xué)意義(P≤0.05)。3.B-ALL中,mi R-495低甲基化組(24例)誘導(dǎo)治療后其臨床危險度分級均未改變,高甲基化組(39例)誘導(dǎo)治療后其臨床危險度分級28例(71.79%)存在危險度調(diào)高,mi R-495高甲基化組誘導(dǎo)緩解后其臨床危險度上調(diào)的比例明顯高于低甲基化組(P≤0.05)。4.ALL中mi R-495甲基化水平與表達(dá)水平之間無明顯相關(guān)關(guān)系(P0.05)。結(jié)論:兒童ALL mi R-495表達(dá)水平明顯低于ITP及健康兒童對照組;ALL中mi R-495高表達(dá)組B-ALL較T-ALL比例顯著增加,提示mi R-495在ALL中可能起到腫瘤抑制作用;mi R-495甲基化水平的升高與誘導(dǎo)緩解療效不佳有關(guān),有望成為對ALL化療療效評估的一個生物學(xué)指標(biāo);兒童ALL中mi R-495甲基化水平與表達(dá)水平之間無明顯相關(guān)關(guān)系,mi R-495甲基化可能并非調(diào)控其表達(dá)水平的主要因素。
[Abstract]:Objective: micro RNA-495 (mi R-495) may play a role in tumor suppressor or carcinogenesis in different tumors. The expression of mi R-495 is correlated with the degree of CPG island methylation in promoter region. No related studies have been found in ALL in children. The purpose of this study was to investigate the significance of mi R-495 in the pathogenesis of ALL in children by detecting and analyzing the difference of mi R-495 expression and methylation status in ALL, and to understand the expression level, methylation status and ALLT/B typing of mi R-495 in children. The relationship between TEL/AML1 fusion gene and induced remission effect. Methods: bone marrow (bone marrow,BM) and peripheral blood of 80 children with non-hyperdiploid ALL were collected as experimental group, 10 children with immunologic thrombocytopenic purpura (immune thrombocytopenia,ITP) and 31 healthy children as control group. Extraction of ALL and ITP and DNA and RNA. from normal Peripheral Blood DNA was treated with heavy sulfite and mi RNA with reverse transcription. The methylation level of CPG island in the promoter region of mi R-495 gene was detected by methylation-sensitive high-resolution dissolving curve analysis (methylation sensitivity of high resolution melting curve analysis,MS-HRM) method. The expression of mi R-495 was detected by real-time fluorescence quantitative PCR. Results: the expression level of 1.mi R-495 in ALL group was 1.2800E-4 (8.5450E-6n 1.5450E-3). It was significantly lower than that in ITP group [9.9500E-2 (4.7963E-2n 1.4302E-1)] and normal control group [1.4800E-3 (6.1050E-4n 4.0850E-3)] (P < 0. 05). There were 36 cases with high mi R-495 expression in 2.ALL. There were 35 cases of B-ALL and 1 case of T-ALL. 44 cases of low expression group, including B-ALL33, 11 T-ALL, mi R-495 high expression group and low expression group, there was significant difference in B / T ratio between the two groups (P 鈮，

本文編號：2328263