重型β-珠蛋白生成障碍性贫血患儿hTERT基因表达的研究

hTERT gene expression in children with β-thalassemia major

摘要:

目的：骨髓人类端粒酶催化亚单位（hTERT）是控制人细胞端粒酶活性的限速成分，决定了细胞寿命。该研究初步探讨重型β-珠蛋白生成障碍性贫血hTERT表达的变化及其与外周血红蛋白水平的关系。方法：多重等位基因特异聚合酶链反应(MASPCR)分析重型β-珠蛋白生成障碍性贫血患儿的基因类型，半定量逆转录-聚合酶链反应(RT-PCR)检测重型β-珠蛋白生成障碍性贫血和粒细胞减少症患儿骨髓和阳性对照K562细胞株的hTERT相对表达水平，常规检测患儿外周血血红蛋白水平。Spearman直线相关分析hTERT表达与外周血血红蛋白水平的关系。结果：重型β-珠蛋白生成障碍性贫血患儿组骨髓hTERT相对表达水平高于粒细胞减少症患儿组（0.2928±0.0838 vs 0.0993±0.0336, P<0.01），但明显低于K562细胞株(0.8291±0.0908, P<0.01)。重型β-珠蛋白生成障碍性贫血患儿组骨髓hTERT表达与其外周血血红蛋白水平呈负相关（r=-0.841，P<0.01）。结论：重型β-珠蛋白生成障碍性贫血患儿慢性溶血时，低水平血红蛋白可能在一定范围内上调骨髓hTERT基因表达水平。［中国当代儿科杂志，2009，11（6）：449-452］

Abstract:

OBJECTIVE: Human telomerase reverse transcriptase (hTERT) is a rate-limiting enzyme which dictates the activity of human telomerase and thus decides the life span of cells. The aim of this study was to explore the expression of hTERT in bone marrow from children with β-thalassemia major and the relationship between the expression of hTERT and hemoglobin levels. METHODS: Multiple allele specific polymerase chain reaction (MASPCR) was used for targeted DNA amplification and gene mutation analysis of β-thalassemia. hTERT mRNA expression in bone marrow was examined using real-time reverse transcription polymerase chain reaction (RT-PCR) analysis in 29 children with β-thalassemia major, in 10 children with agranulocytosis and in K562 cell line. The hemoglobin levels in peripheral blood were measured. The relationship between hTERT expression and hemoglobin levels was evaluated by the Spearman test in the β-thalassemia major group. RESULTS: hTERT mRNA expression significantly increased in bone marrow from children with β-thalassemia major compared with that from children with agranulocytosis (0.2928±0.0838 vs 0.0993±0.0336; P<0.01), but was significantly lower than that in K562 cell line (0.8291±0.0908) (P<0.01). A significantly inverse correlation was found between hTERT mRNA expression and hemoglobin levels (r=-0.841, P<0.01). CONCLUSIONS: A low hemoglobin concentration might contribute to the up-regulation of marrow hTERT expression in children with β-thalassemia major.［Chin J Contemp Pediatr, 2009, 11 (6):449-452］