建立实时定量PCR检测急性早幼粒细胞白血病PML/RARa融合基因转录本

目的 建立实时定量PCR(real-time quantitative PCR,RQ-PCR)法榆测急性早幼粒细胞白血病(acute promyelocytic leukemia,APL)PML/RARa融合基因转录本,评价其在APL患者诊断和微小残留病(minimal residual disease,MRD)监测中的意义.方法 设计TaqMan探针和引物,建立RQ-PCR法对长型(L-form)、短型(S-form)、变异型(V-form)不同类型PML/RARa阳性模板进行扩增,并检测6例APL患者PML/RARa融合基因转录本含量.结果 RQ-PCR法最低可检测到10个拷贝/μL的阳性模板,但重复性较差,而108～102拷贝/μL阳模的重复性良好,止常对照无扩增信号.6例初诊APL患者不同类型PML/RARa融合基因转录本绝对含量为4.27×103～3.36×105拷贝/50 ng(中位4.33×104拷贝/50 ng),ABL纠正后的相对含量为29.38%～600.53%(中位48.12%).1例患者诱导缓解后PML/RAHa融合基因转录本下降,复发时义明显升高.结论 RQ-PCR方法敏感、可靠,可用于APL患者的诊断和MRD监测.     

三氧化二锑诱导急性早幼粒细胞白血病细胞凋亡的研究

目的 研究锑剂三氧化二锑（Sb2O3)对早幼粒细胞白血病细胞株NB4凋亡的诱导作用，以寻求早幼粒细胞白血病治疗的新方法。方法 采用细胞生长曲线，形态学及硝基四氮唑蓝（NBT）还原试验，判定NB4细胞的生长，分化及功能。采用细胞周期分析和DNA电泳研究细胞凋亡。结果 Sb2O3能诱导早幼粒白血病细胞凋亡，且具有时间，剂量依赖性。结论 Sb2O3能有效地诱导早幼粒白血病细胞凋亡，提示锑剂诱导细胞半亡的疗法，有望成为临床治疗早幼粒细胞白血病的新方法。     

ATRA诱导SP100蛋白表达及其对白血病NB4细胞增殖的影响

目的探讨SP100蛋白在全反式维甲酸(ATRA)作用NB4细胞过程中的表达及其对NB4细胞增殖和周期的影响。方法实时定量PCR检测SP100 mRNA的表达;Western blot检测SP100蛋白的表达;免疫荧光检测SP100的定位;CCK-8检测NB4细胞的增殖;流式细胞术检测NB4细胞的周期。结果 ATRA能明显促进NB4细胞中SP100mRNA水平和蛋白水平,并将SP100由弥散的小点状转变为较大的斑块状;感染SP100-shRNA的NB4细胞增殖活力明显高于未感染组和病毒空载组(P0.05),并使G2/M期的细胞增多。结论 ATRA促进NB4细胞中SP100蛋白的表达,SP100蛋白可能参与NB4细胞增殖活力的调节。     

HLA-DR阴性的急性髓系非早幼粒细胞白血病

正正常髓系细胞分化成熟的过程中,人类白细胞抗原(简称HLA-DR)可表达在造血祖细胞,粒细胞、单核细胞及巨核细胞的前体细胞上,但在早幼粒细胞阶段往往缺乏,与之相一致的是绝大多数的早幼粒细胞白血病细胞上也缺乏HLA-DR     

48例急性早幼粒细胞白血病的细胞遗传学研究

目的　探讨不同病期急性早幼粒细胞白血病 (APL)的细胞遗传学特点及意义。方法　随机选取 4 8例APL患者 ,采集新鲜骨髓 ,采用 2 4h预加秋水仙素的短期培养法制备染色体 ,应用G显带技术进行核型分析并照相。结果　本研究4 8例患者 (未缓解期 16例 ,复发期 3例 ,完全缓解期 2 9例 )中 ,具有染色体异常的有 2 8例 ,其中未缓解期 16例 (16 /16 ) ,复发期 3例 (3/3) ,完全缓解期 9例 (9/2 9)。异常类型以染色体易位和片段缺失比例较高 ,其中具有典型t(15 ;17)易位者 7例 ,为未缓解期或复发期患者 ;易位涉及 8q2 2者 5例。其中 ,同时具有t(15 ;17) ,t(8;2 1)易位 1例 ;同时具有t(5 ;8) ,t(15 ;17)易位 1例 ;t(5 ;8)易位 1例 ;t(8;17)易位 1例 ;以t(8;2 1)为基础的复杂易位 1例。具有 17q2 1-者 6例。结论　对白血病进行细胞遗传学研究不但具有十分重要的诊断和预后价值 ,而且能发现与疾病发生有关的新基因及涉及白血病转化和增殖的分子损伤位点。     

三氧化二砷治疗复发性急性早幼粒细胞白血病临床观察

目的 探讨三氧化二砷治疗复发性早幼粒细胞白血病的疗效.方法 对9例复发的急性早幼粒细胞白血病患者应用三氧化二砷治疗,观察其完全缓解率.结果 9例中完全缓解6例,占66.7%,有效率77.8%.结论 三氧化二砷治疗复发性早幼粒细胞白血病,其完全缓解率高,且与维甲酸与化疗药物之间无交叉耐药,副作用小,值得临床推广应用.     

三氧化二砷治疗复发性急性早幼粒细胞白血病临床观察

目的 探讨三氧化二砷治疗复发性早幼粒细胞白血病的疗效.方法 对9例复发的急性早幼粒细胞白血病患者应用三氧化二砷治疗,观察其完全缓解率.结果 9例中完全缓解6例,占66.7%,有效率77.8%.结论 三氧化二砷治疗复发性早幼粒细胞白血病,其完全缓解率高,且与维甲酸与化疗药物之间无交叉耐药,副作用小,值得临床推广应用.     

急性早幼粒细胞白血病68例回顾性临床分析

目的探讨初治中低危急性早幼粒细胞白血病(APL)患者诱导缓解治疗及完全缓解(CR)后的治疗方案。方法回顾性分析68例初治APL患者3种不同诱导治疗方法CR率、达CR所需时间及副作用,并分析CR后不同巩固治疗方案对预后的影响。结果全返式维甲酸(ATRA)联合蒽环类药物化疗、单用亚砷酸(AS2O3)及ATRA+AS2O3+化疗3种方法治疗初诊APL完全缓解率分别为90%、89%、89%,无显著差异,P>0.05;ATRA+AS2O3+化疗组达CR所需时间最短,ATRA+化疗组副作用最少,P<0.05;CR后选用ATRA、AS2O3、化疗序贯治疗能明显延长患者无病生存期。结论 ATRA+化疗方案可做为初治APL患者诱导缓解的首选方案;ATRA、AS2O3、化疗序贯治疗均可做为CR后的有效治疗方案,中低危患者可不必联用Ara-c化疗。     

15;17 translocation in acute promyelocytic leukemia

Acute promyelocytic leukemia (APL) is a relatively rare subtype of leukemia that has been reported to be associated with a specific chromosome abnormality, t(15;17). It has been suggested that this translocation may have a geographical distribution and its presence may signify a poorer prognosis. In this present series of 14 patients with APL, 9 patients (64%) had the t(15;17) and 5 did not; however, no significant differences in clinical features or outcome could be found between those who did and those who did not express the translocation. When ethnic backgrounds were explored, no differences were found. More cases of the t(15;17) were found in recent years (7 of 8 patients studied since 1978 compared to 2 of 6 before 1978). This corresponded to changes made in our cytogenetic techniques suggesting that the finding of the t(15;17) may be a function of technique, rather than a real difference in disease entities, and all patients with APL may have the t(15;17) when appropriately studied.     

Pathogenetic implication of fusion genes in acute promyelocytic leukemia and their diagnostic utility

Acute promyelocytic leukemia (APL) has been recognized as a discrete subset of hematopoietic malignancies constituting approximately 10% of acute myeloid leukemia cases. The hallmark reciprocal chromosomal translocation t(15;17) involving fusion between the retinoic acid receptor (RARα) gene and promyelocytic leukemia (PML) gene is a characteristic feature in APL which consequently results in the emergence of PML-RARα chimeric gene. This gene has been substantiated to be responsible for cellular transformation and is a prime target of all-trans-retinoic acid (ATRA) as well as arsenic-trioxide (ATO) therapy. Since this initial discovery, about 10 diverse translocation partner genes of RARα have been reported that result in variant APL forms strongly suggesting that disruption of RARα underlies its pathogenesis. The nature of the fusion partner has a significant bearing upon disease characteristics including sensitivity to retinoids and ATO and thereby underpins the need for rapid and accurate diagnosis and also demands a highly specific treatment approach. In this article we laid emphasis on the rearrangement of the RARα gene and its different fusion partners resulting in variant forms of APL, their implication in underlying molecular pathogenesis of APL and also the different diagnostic modalities that should be employed for their rapid and accurate diagnosis.     

Cytogenetic findings in patients with acute promyelocytic leukemia and a case of CML blast crisis with promyelocytic proliferation

Nineteen patients with acute promyelocytic leukemia (APL) and one with promyelocytic blast crisis were studied by a methotrexate cell synchronization technique and by 24-hour short-term culture. Nineteen cases of APL included two cases of the microgranular variant (M3V). Except in one case of M3V, t(15;17) was detected in all patients. The breakpoints were determined as 15q22 and 17q12-21. A chronic myeloid leukemia (CML) blast crisis patient with high promyelocyte count also had a t(15;17) as well as a masked Ph chromosome. Other abnormalities, such as +8,del(7q) and an i(17q), were also observed in some patients. Our studies have indicated that 1) the translocation (15;17), characteristic of APL, was present in our population in almost all patients; 2) the presence of an identical abnormality in a promyelocytic CML blast crisis supported and confirmed the phenomenon of association of specific chromosome change with target cell type; and 3) the precise localization of breakpoints on chromosome 17 is still difficult to determine. The identification of as yet unknown genes at region 17q11-q21 and their subsequent translocation on chromosome 15 will help in assigning a precise position to these breakpoints.