骨髓组织PTENmRNA和hTERT、DNA-PKcs检测对急性白血病的临床意义

Clinical Significance of Expression Levels of PTENmRNA and hTERT,DNAPKcs in Bone Marrow for Childhood Acute Leukemia

目的研究抑癌基因、端粒酶及DNA修复基因在白血病细胞中的表达,探讨其临床意义。方法收集儿童急性白血病骨髓活检标本45例(包括初诊组25例和缓解组20例),以及对照组非白血病患儿骨髓标本20例。(1)以骨髓组织石蜡切片作原位杂交PTENmRNA检测,并用免疫组化EliVision法检测端粒酶催化亚单位(hTERT)和DNA依赖蛋白激酶催化亚单位(DNA-PKcs)的表达。比较3组差异。(2)初诊组中20例治疗4周,观察疗效与3项指标表达的关系。结果(1)白血病初诊组骨髓腔充满白血病细胞。PTENmRNA失表达40．0％,hTERT阳性表达84．0％,DNA-PKcs失表达28．0％;3项表达水平均与缓解组和对照组差别显著(P＜0．05)。(2)化学药物治疗4周,未完全缓解者5例;PTENmRNA失表达者占4例,CR率低于阳性表达者(P＜0．05);hTERT和DNA-PKcs阳性表达者各占4例,但无统计学显著差异(P＞0．05)。结论(1)骨髓活检有助于白血病诊断和疗效判定。(2)儿童急性白血病显示有PTENmRNA、hTERT及DNA-PKcs表达异常,表明抑癌基因、端粒酶和DNA修复基因在白血病发生中起到重要作用,可作为基因诊断。(3)白血病初诊组与缓解组显著差别,可辅助疗效判定。(4)治疗效果与多因素相关,PTENmRNA失表达可影响疗效,显示有预测预后价值。

Objective To study the expression and clinical significance of tumor suppressor gene, DNA repair gene and telomerase compoment in acute leukemia. Methods 45 children with acute leukemia were studied including 25 cases of first diagnosed and 20 cases of remission, and 20 children without acute leukemia as contrasts.（1）Check the expression levels of PTENmRNA on paraffin-embedded sections of marrow biopsy samples by in situ hybridization, and check the expressions of hTERT and DNA-PKcs by immunohistochemistry.Compare the differences of three groups.（2）Observe the relationship between curative effects and the expression levels of three items after 4 weeks treatment in 20 cases of first diagnosed children.Results （1）Leukemic cells can be seen all over the marrow cavity in first diagnosed group.In this group,loss expression rate of PTENmRNA is 40.0%,positive rate of hTERT is 84.0 %,and loss expression rate of DNA-PKcs is 28.0%;differences of the expressions between first diagnosed group and remission group or contrast group are notable （P〈0.05）.（2） After treating for 4 weeks in 20 cases of first diagnosed children,5 cases cannot get complete remission （CR）; Among them there are 4 cases with loss expression of PTENmRNA,4 cases with positive expression of hTERT, and 4 cases with positive expression of DNA-PKcs;patients with negative PTENmRNA expression have lower CR rate than positive ones （P〈0.05）.Conclusions （1） Marrow biopsy is helpful for diagnosis and judgement of curative effect in leukemia. （2）Childhood acute leukemia shows abnormal expression of PTENmRNA,hTERT and DNA- PKcs,indicating that tumor suppressor gene, DNA repair gene and telomerase have an important role in the occurrence of childhood acute leukemia.（3）Exp ression levels in first diagnosed group and remission group are of greatdifference,which is beneficial for judging curative effect.（4） Curative effects are related to multi-factors;loss expression of PTENmRNA in our experiment may influence it, which may contributes to estimate the prognosis.