Mutations of retinoblastoma gene (Rb-1) as a prognostic factor in children with acute leukemia and neuroblastoma

Rb-1 is a tumor suppressor gene encoding for a nuclear phosphoprotein acting as a cell cycle regulator, normally expressed in hematopoietic cells and more often inactivated by point mutations with predominance for exons 20-24. The aim of this study is to correlate the retinoblastoma-1 (Rb-1) gene mutations with the prognosis and progression of childhood acute leukemia and neuroblastoma. Bone marrow slides from 26 children with leukemia (18 acute lymphoblastic leukemia [ALL] and 8 acute myeloid leukemia [AML]) and 4 children with neuroblastoma were studied. Exons 20, 21, and 22 were amplified using the polymerase chain reaction technique. Single strand conformational polymorphism (SSCP) and heterodoublex analysis were performed to detect mutations. In ALL cases, two samples in exon 20 (11.11%), one in exon 21 (5.56%), and four in exon 22 (22.22%) had altered conformation. All but one of these cases were classified as high-risk leukemia patients who either relapsed or never achieved remission. Two of the AML cases who did not achieve remission and one of the neuroblastoma cases with concomitant bone marrow infiltration had altered conformation as well. The SSCP and heterodoublex analysis showed that all but one who did not belong to the high-risk group had the same altered conformation. These data suggest that Rb-1 gene could possibly be used as an independent prognostic factor for the acute leukemia of childhood and result in the intensification of chemotherapy. In solid tumors with bone marrow involvement it could play a role as a marker of aggressive disease.     

儿童急性髓细胞白血病WT1基因表达及其临床意义

目的研究急性髓细胞白血病(AML)患儿WT1基因表达情况及其与临床预后的关系。方法采用实时荧光定量PCR方法检测45例非M3儿童AML的WT1表达水平,并回顾性分析其与AML预后的关系。结果骨髓幼稚细胞比例60%的AML患儿WT1表达水平高于幼稚细胞≤60%的患儿(P0.05)。M2病例组初诊时WT1表达量低于非M2病例组(P0.05)。完全缓解组患儿的WT1表达量显著低于初诊组和复发组(P0.01)。诱导化疗结束时WT1高表达组的2年无病生存率(DFS)低于WT1低表达组(P0.05)。诱导化疗结束时WT1下降程度≥1个数量级病例组的2年总生存率(OS)和DFS高于WT1下降程度1个数量级病例组(P0.05)。AML患儿骨髓复发2~3个月前WT1表达呈上升趋势。结论 WT1表达水平与儿童AML预后密切相关,动态监测WT1表达在指导儿童AML个体化治疗、预后评估和复发预测方面具有重要临床应用价值。     

Follow-up of minimal residual disease in acute childhood lymphoblastic leukemia by WT1 gene expression in the peripheral blood: the Hungarian experience

The aim of the study was to investigate if monitoring WT1 gene expression in the peripheral blood is an appropriate approach to monitor the progression of childhood acute lymphoblastic leukemia (ALL). Forty-six patients have been enrolled into this study (24 ALL and 22 control, nonleukemic cases). The peripheral blood was tested for WT1 gene expression using a sensitive nested RT-PCR technique. The assay was sensitive enough to detect 10 2 leukemic cells among 10 6 normal leukocytes. In agreement with the literature 96% of childhood ALL (23/24) expressed WT1 independent of the prognostic factors of the disease. On the other hand, no WT1 gene expression was found in the peripheral blood of nonleukemic hematological diseases, except myelodysplasia. WT1 became negative in the peripheral blood of these patients at the end of the induction phase of the therapy in the majority of the cases (19/24), whereas clinical remission was achieved in all patients except one. WT1 gene expression changes in the peripheral blood was monthly monitored in 20 ALL patients for 1 year and in 16 cases during the second year (for a maximum of 21 months). Although continuous monitoring detected transient (1- to 3-month long) WT1 expression in the majority of the ALL cases (16/20), clinical relapse occurred in 2 cases only when the WT1 expression was maintained for 11-15 months. Follow up studies of the WT1 gene expression in the peripheral blood of WT1-positive childhood ALL may enable researchers to monitor MRD and detect a very low leukemic cell count (perhaps called "molecular relapse"). According to this study, the transient WT1 positivity for 1-3 months does not predict clinical relapse of childhood ALL, unlike a longer-lasting positivity.     

急性淋巴细胞性白血病患儿WT1基因与肿瘤耐药基因表达的关系

目的　探讨儿童急性淋巴细胞性白血病 (ALL)WT1基因与肿瘤多药耐药基因 (mdr1)表达的关系 ,为临床判断预后、指导个体化治疗提供依据。方法　采用逆转录聚合酶链反应 (RT PCR)对 33例ALL患儿的同一份标本进行WT1mRNA及mdr1mRNA检测 ,用GQS 96 0图像处理系统软件进行半定量分析。结果　 (1)初治组ALL的WT1及mdr1阳性率分别为 6 7%及 15 % ,完全缓解组分别为 2 2 %及 18% ,复发难治组分别为 92 %及 75 % ,初治组和复发难治组WT1阳性率及表达水平与完全缓解组相比 ,P均 <0 0 1,复发难治组中mdr1阳性率及表达水平与初治组和完全缓解组相比 ,P均 <0 0 1,差异均有极显著性 ;(2 )WT1与mdr1表达无明显相关关系 ,但复发难治组WT1与mdr1均阳性者多 ,占 6 7% ,均阴性的为 0 ;与初治组及完全缓解组比较差异有极显著性。结论　ALL患儿WT1基因表达的同时出现肿瘤多药耐药基因表达 ,是白血病难治及复发的重要因素 ,提示预后差。动态监测WT1及mdr1,可预测白血病难治及复发 ,指导个体化治疗 ,有利于清除微小残留白血病细胞     

原癌基因Fra-1在肾母细胞瘤患儿血液中的表达及其意义

目的 探讨原癌基因Fra-1在肾母细胞瘤患儿血液中的表达及其意义。方法 选取2012年12月至2018年1月病理明确诊断为肾母细胞瘤的患儿作为病例组（n=50）,健康体检儿童作为对照组（n=40）;获得随访的45例患儿中,将持续缓解患儿纳入理想疗效组（n=33）,复发、转移或死亡患儿纳入疗效不佳组（n=12）。采集所有研究对象外周血,通过实时荧光定量PCR检测Fra-1 mRNA表达水平。结果 肾母细胞瘤患儿血液中Fra-1 mRNA相对表达量明显高于对照组（P < 0.05）。Fra-1 mRNA的表达水平在肾母细胞瘤是否远处转移及TNM分期间比较差异有统计学意义（P < 0.05）,而在患儿的性别、年龄、肿瘤直径、肿瘤位置及不同甲胎蛋白（AFP）水平间比较差异均无统计学意义（P > 0.05）。理想疗效组Fra-1 mRNA相对表达量低于疗效不佳组（P < 0.05）。结论 Fra-1可能参与肾母细胞瘤的形成,并在其发展、侵袭及转移中起一定作用,但具体机制仍有待深入研究。     

Laparoscopic adnexectomy of a persistent ovarian tumor in a girl with acute lymphoblastic leukemia relapse

The management of children with acute lymphoblastic leukemia (ALL) relapse and an ovarian tumor remains controversial. The authors report about a 4-year-old girl who developed a late bone marrow and cutaneous relapse of her pre-B-cell ALL and revealed an enlargement of her left ovary (4 ×3 ×2 cm). Chemotherapy (ALL-REZ-BFM pilot-protocol 2002) achieved effective remission, but the ovarian mass depicted no regression. Laparoscopic adnexectomy was performed and the tumor could be extracted in a specimen-bag through a 12-mm umbilical incision. Histology detected no viable lymphoblasts, but a fibrotic enlargement due to previous cellular infiltration. The authors conclude that in children with ALL relapse and an ovarian tumor, malignant infiltration as well as local response to chemotherapy can be judged only by surgical excision and histopathologic examination. Laparoscopic oophoradnexectomy is a valuable management option in these children.     

MUTATIONS OF RETINOBLASTOMA GENE (Rb-1) AS A PROGNOSTIC FACTOR IN CHILDREN WITH ACUTE LEUKEMIA AND NEUROBLASTOMA

Rb-1 is a tumor suppressor gene encoding for a nuclear phosphoprotein acting as a cell cycle regulator, normally expressed in hematopoietic cells and more often inactivated by point mutations with predominance for exons 20-24. The aim of this study is to correlate the retinoblastoma-1 (Rb-1) gene mutations with the prognosis and progression of childhood acute leukemia and neuroblastoma. Bone marrow slides from 26 children with leukemia (18 acute lymphoblastic leukemia [ALL] and 8 acute myeloid leukemia [AML]) and 4 children with neuroblastoma were studied. Exons 20, 21, and 22 were amplified using the polymerase chain reaction technique. Single strand conformational polymorphism (SSCP) and heterodoublex analysis were performed to detect mutations. In ALL cases, two samples in exon 20 (11.11%), one in exon 21 (5.56%), and four in exon 22 (22.22%) had altered conformation. All but one of these cases were classified as high-risk leukemia patients who either relapsed or never achieved remission. Two of the AML cases who did not achieve remission and one of the neuroblastoma cases with concomitant bone marrow infiltration had altered conformation as well. The SSCP and heterodoublex analysis showed that all but one who did not belong to the high-risk group had the same altered conformation. These data suggest that Rb-1 gene could possibly be used as an independent prognostic factor for the acute leukemia of childhood and result in the intensification of chemotherapy. In solid tumors with bone marrow involvement it could play a role as a marker of aggressive disease.     

The role of short course of high-dose methylprednisolone in children with acute myeloblastic leukemia (FAB M2) presented with myeloid tumor

The authors have previously demonstrated a favorable effect of high-dose methylprednisolone (HDMP), which can induce differentiation and apoptosis of leukemic cells in children with acute myeloblastic leukemia (AML). Here, they evaluate the effect of short-course HDMP in 2 children with acute myeloblastic leukemia (AML-M2) presented with myeloid tumor (MT). Methylprednisolone (20 or 30 mg/kg/day) was given orally, in a single dose, without using other antileukemic agents. Rapid cytoreduction in MT, peripheral blood, and bone marrow blasts was observed in both children following short-course (4 or 7 days) HDMP treatment, possibly due to HDMP-induced differentiation and apoptosis of leukemic cells. The effects of HDMP should be explored in patients with other subtypes of AML who present with MT.     

WT1、PRAME、ERG基因在急性髓系白血病中的研究进展

白血病特异性基因是目前监测白血病微小残留病灶的主要生物学标记.近年来发现PRAME、WT1、ERG等可能是潜在的急性白血病相关分子,可用于急性髓系白血病(AML)微小残留病的监测,用来指导临床分层治疗和判断预后.该文就这些白血病相关分子的致病机制、在白血病中的发生率及与临床预后的关系等做一综述.     

21例伴有AML1/ETO融合基因表达的儿童急性非淋巴细胞白血病的分析

目的 对急性髓细胞性白血病1(AML1)／ETO(eight twenty one)融合基因阳性及阴性的两组病例的主要临床指标进行比较分析,并探讨AML1／ETO融合基因检测在儿童急性非淋巴细胞白血病(ANLL)的临床诊断及预后判断中的意义。方法 采用巢式逆转录聚合酶链反应(RT-PCR))检测白血病患儿AML1／ETO融合基因,并进行法-美-英(FAB)及形态学-免疫学-细胞遗传学(MIC)分型。诱导治疗主要采用柔红霉素、阿糖胞苷(DA)、DA 依托泊甙(足叶乙甙,DAE)、柏林-法兰克福-慕尼黑(BFM)方案。结果 在21例AML1／ETO融合基因表达的ANLL中,经FAB及MIC分型,17例为急性粒细胞白血病部分分化型(M2),占81％,另外4例分别是骨髓异常增生综合征-转化中的原始细胞增多的难治性贫血(MDS—RAEB—T)后转为M2型1例,急性粒单细胞白血病伴嗜酸细胞增多(M4EO)1例,急性单核白血病(M5)1例和嗜酸性粒细胞白血病1例。可评定疗效的20例中,18例达到完全缓解(CR),CR率达90％。8例同期收治的ANLL无融合基因和基因异常的病例,CR率达87．5％。结论 AML1／ETO融合基因阳性及阴性的两组病例,在各主要临床指标方面差异没有显著性。采用RT—PCR检测白血病患儿AML1／ETO融合基因是一种快速、简便、灵敏的辅助诊断方法,对ANLL的诊断及预后判断有重要的临床价值。     

Pulmonary tuberculosis in children with acute lymphatic leukemia

Four children with acute lymphatic leukemia developed pulmonary tuberculosis. Three developed tuberculosis soon after the remission was achieved, while one case developed it after 25 months of complete remission. Higher prevalence of tuberculosis in immunocompromised hosts especially in countries where incidence of tuberculosis in high is not well recognised. Early recognition and appropriate treatment of such cases is emphasized.     

小儿紫癜性肾炎Pax2与WT1表达关系研究

目的探讨Pax2与WT1在紫癜性肾炎(HSPN)肾组织中的表达及其两者间的关系。方法选取2004年7月至2005年12月在中南大学湘雅二医院住院的HSPN患儿37例为试验组,肾病综合征患儿(微小病变型)10例为对照组。分别对肾小球和肾小管间质的病理改变程度进行半定量评分,免疫组化检测Pax2与WT1的表达,分析肾脏Pax2、WT1表达与肾脏病理积分及其两者之间的关系。结果(1)HSPN患儿肾组织局部Pax2的表达:Ⅱ级1.14±0.38;Ⅲa级1.71±0.47;Ⅲb级2.58±0.51;Ⅳ级3.00±0.00;对照组0.80±0.45。HSPN患儿与对照组之间和HSPN患儿肾脏病理改变各级间,Pax2的表达差异均有统计学意义(P<0.005),随着肾脏病理级别的加重,Pax2的表达增加。(2)HSPN患儿肾组织局部WT1的表达:Ⅱ级2.78±0.38;Ⅲa级1.86±0.53;Ⅲb级1.50±0.52;Ⅳ级1.50±0.58;对照组2.60±0.54。HSPN患儿与对照组之间和HSPN患儿肾脏病理改变多级间,WT1的表达差异有统计学意义(P<0.05),肾脏病理级别的加重,WT1的表达增加。结论HSPN患儿中存在PaX2的重新表达和WT1的表达减少,且随着肾脏病理加重Pax2的表达增加,WT1的表达减少。     

伴t(8;21)/AML1-ETO的儿童急性髓系白血病的临床研究

目的探讨伴t(8;21)/AML1-ETO的儿童急性髓系白血病(AML)的临床及生物学特征。方法52例初治患儿,男34例,女18例,中位年龄12(4~18)岁,均进行了遗传学和/或AML1-ETO融合基因检测。诱导缓解治疗采用HA/DA/HAD方案,缓解后进行异基因造血干细胞移植或7~12疗程的联合化疗。结果24%的儿童AML伴t(8;21)/AML1-ETO,男女比例1·9,FAB分型为M250例(96%);初诊时伴中枢神经系统浸润7·7%(4/52);WBC17·2(1·8~146·3)×109/L,初诊时WBC大于10×109/L者50·0%(26/52),大于50×109/L者3·8%(2/52),血清乳酸脱氢酶升高者85·7%(36/42);细胞免疫分型CD19(44·4%),CD56(58·9%);单独为t(8;21)异常的13例(28·9%),Y染色体丢失22例,占男性患儿的64·7%;X染色体丢失3例,占女性患儿的16·7%,del(9q)6例;1疗程及2疗程完全缓解(CR)率分别为71·8%(28/39)和94·4%(34/36),4年的EFS率、DFS率和OS率分别为(25·4±9·6)%、(28·4±10·4)%和37·9±10·3)%。结论近1/4的儿童AML伴t(8;21)/AML-ETO,多见于FAB分型的M2型,男性居多,年长儿多发,易发生髓外浸润;高白细胞者少见,血清乳酸脱氢酶增高,细胞免疫分型较多表达CD19和CD56;细胞遗传学检查常伴有性染色体丢失和del(9q);诱导缓解治疗完全缓解率高,应用联合化疗进行巩固强化远期疗效好     

Immunohistochemical nuclear positivity for WT1 in childhood acute myeloid leukemia

Several studies have reported previously that acute myeloid leukemia (AML) may express WT1 detected by RT-PCR and/or Northern blotting. The diagnostic utility of WT1 expression in AML using immunohistochemistry has not been reported previously. Paraffin-embedded tissue sections from 55 AML, 12 acute lymphoblastic leukemia (ALL), and 10 normal bone marrow specimens were immunostained for WT1 (anti-N terminus antibody). 22/55 AML cases (40%) demonstrated nuclear immunopositivity for WT1, including 20/47 bone marrow trephines and 2/4 granulocytic sarcomas. All the ALL and normal bone marrow specimens were negative. A significant proportion of AML expresses nuclear immunostaining for WT1, a finding that has only been described previously in Wilms' tumor and desmoplastic small round cell tumor. This finding is important for the correct interpretation of immunohistochemical findings in the diagnosis of “small round cell” tumors of childhood, especially in cases of extramedullary deposits of AML, in which traditional myeloid markers may be negative.     

Convergent evolution of 11p allelic loss in multifocal Wilms tumors arising in WT1 mutation carriers

Wilms tumors in patients with constitutional WT1 mutations are examples of Knudson's tumor suppressor paradigm, with somatic inactivation of the second allele occurring through 11p loss of heterozygosity. The time point of this second hit has remained unknown. We analyzed seven Wilms tumors from two patients with constitutional WT1 mutations by whole exome sequencing and genomic array. All tumors exhibited wild type WT1 loss through uniparental isodisomy. Each tumor had a unique genomic breakpoint in 11p, typically accompanied by a private activating mutation of CTNNB1. Hence, convergent evolution rather than field carcinogenesis underlies multifocal tumors in WT1 mutation carriers.     

WT1基因检测时机对Wilms肿瘤合并慢性肾脏疾病预后影响的回顾性队列研究

目的 分析在Wilms肿瘤合并慢性肾脏疾病(CKD)的患儿中WT1基因检测对诊断和长期预后的影响。方法 检索上海市肾脏发育与儿童肾脏病研究中心儿童肾脏病基因检测数据库,2001年1月1日至2018年12月31日明确WT1基因突变、年龄<18岁患儿,或Wilms肿瘤合并CKD 2~5期或肾病综合征或有蛋白尿的连续病例。按进展为终末期肾衰竭(ESRD)之前是否明确WT1基因突变分为早诊断组和晚诊断组,以ESRD为终点比较两组的预后。结果 22例患儿明确WT1基因的常染色体显性遗传突变,分别位于第8~9外显子/内含子。依据临床分型,10例为Denys-Drash综合征,3例为Fraiser综合征,9例表型为孤立型肾病综合征,5例合并假两性畸形。随访终点进入ESRD有15例,7例进入CKD 2~4期。应用生存曲线分析证实,早诊断组较晚诊断组进入ESRD病程显著延迟(P=0.011)。结论 在儿童Wilms肿瘤、肾病综合征/蛋白尿、慢性肾功能损害的患儿中,在肾功能进展恶化之前及早明确WT1基因突变,不仅有助于临床诊断分型,还能显著延缓进入ESRD病程。     

WT1基因检测时机对Wilms肿瘤合并慢性肾脏疾病预后影响的回顾性队列研究

目的 分析在Wilms肿瘤合并慢性肾脏疾病(CKD)的患儿中WT1基因检测对诊断和长期预后的影响。方法 检索上海市肾脏发育与儿童肾脏病研究中心儿童肾脏病基因检测数据库,2001年1月1日至2018年12月31日明确WT1基因突变、年龄<18岁患儿,或Wilms肿瘤合并CKD 2~5期或肾病综合征或有蛋白尿的连续病例。按进展为终末期肾衰竭(ESRD)之前是否明确WT1基因突变分为早诊断组和晚诊断组,以ESRD为终点比较两组的预后。结果 22例患儿明确WT1基因的常染色体显性遗传突变,分别位于第8~9外显子/内含子。依据临床分型,10例为Denys-Drash综合征,3例为Fraiser综合征,9例表型为孤立型肾病综合征,5例合并假两性畸形。随访终点进入ESRD有15例,7例进入CKD 2~4期。应用生存曲线分析证实,早诊断组较晚诊断组进入ESRD病程显著延迟(P=0.011)。结论 在儿童Wilms肿瘤、肾病综合征/蛋白尿、慢性肾功能损害的患儿中,在肾功能进展恶化之前及早明确WT1基因突变,不仅有助于临床诊断分型,还能显著延缓进入ESRD病程。