Etoposide sensitivity does not predict MLL rearrangements or risk of therapy-related acute myeloid leukemia

Therapy-related acute myeloid leukemia (t-AML) caused by MLL rearrangements (rMLL) can arise from topoisomerase II agents. However, whether rMLL-related leukemogenesis is inextricably linked to drug cytotoxicity remains controversial. We therefore compared (i) rMLL in children with acute lymphoblastic leukemia (ALL) who developed t-AML and those who did not, (ii) epipodophyllotoxin toxicity in patients with t-AML and in controls, and (iii) rMLL in cells sensitive to etoposide and in those resistant to etoposide. In children with ALL, rMLL appeared to be more frequent in children who developed t-AML than in those who did not (seven pairs, P = 0.04), although independent of the cumulative etoposide dose (P = 0.5). Similarly, the frequency of epipodophyllotoxin-related toxicities did not differ between patients with t-AML and controls (26 pairs, P > 0.17). Moreover, in 25 cell lines, etoposide-induced MLL fusions did not differ in sensitive vs. resistant lines at equitoxic concentrations (P = 0.65). Together, these results indicate that epipodophyllotoxin-mediated leukemogenesis is not directly linked to drug cytotoxicity.     

FANCD1在急性髓系白血病细胞中的表达

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MEA方案治疗伴有11q23/混合谱系白血病重排的急性髓性白血病17例疗效分析

目的观察米托蒽醌＋足叶乙甙＋阿糖胞苷（MEA）方案对伴11q23／混合谱系白血病（MLL）重排的急性髓性白血病（AML）患者的治疗效果。方法对诊断明确的17例患者按MEA方案治疗1、2个疗程后评价疗效。结果完全缓解率70．6％，总有效率82．4％。MEA方案的主要副作用为骨髓抑制，但均可耐受。结论MEA方案对伴11q23／MLL重排的AML患者疗效较好，可考虑作为其首选治疗方案。     

Pneumatosis intestinalis in children with acute lymphoblastic leukemia and acute myeloid leukemia

Purpose  

To describe symptoms, diagnostic features, treatments, and outcomes of pneumatosis intestinalis (PI) in pediatric patients being treated for acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML).     

核磷蛋白与急性髓细胞白血病

核磷蛋白(Nueleophosmin,NPM)是一种多功能的核仁磷酸化蛋白,有癌基因和抑癌基因双重特性.NPM1基因突变产生胞质突变蛋白NPMc+,是急性髓细胞白血病(AML)最常见基因异常.NPM1基因突变的AML有独特的特点,包括明显染色体核型正常,不同的血细胞谱系受累,特殊的基因表达,诱导化疗有较好的反应,预后良好.NPMc+突变维持野生型NPM与各种细胞蛋白联系的能力,胞质定位损害其能力.本文总结近年来有关NPM功能发现,讨论NPM1突变AML的发病机理.     

Adult acute myeloid leukemia

Acute myeloid leukemia (AML) is a group of several different diseases, the treatment and outcome of which depend on several factors, including leukemia karyotype, patient age, and comorbid conditions. Despite advances in understanding the molecular biology of AML, its treatment remains challenging. Standard regimens using cytarabine and anthracyclines for induction followed by some form of postremission therapy produce response rates of 60% to 70%, with less than 20% of all patients achieving long-term disease-free survival. New therapies are emerging based on the definition of specific cytogenetic-molecular abnormalities. Such targeted therapies offer the promise of better antileukemic activity in adult AML.     

Programmed death-1 checkpoint blockade in acute myeloid leukemia

Introduction: Immune checkpoints are regulatory pathways induced in activated T lymphocytes that regulate antigen responsiveness. These immune checkpoints are hijacked by tumors to promote dysfunction of anti-tumor effector cells and consequently of tumor escape from the host immune system.

Areas covered: Programmed death-1/programmed death ligand (PD-1/PDL-1), a checkpoint pathway, has been extensively investigated in leukemia mouse models. Expression of PD-1 on the surface of activated immune cells and of its ligands, PD-L1 and PD-L2, on leukemic blasts has been documented. Clinical trials with PD-1 inhibitors in patients with hematological malignancies are ongoing with promising clinical responses.

Expert opinion: Therapy of hematological cancers with antibodies blocking inhibitory receptors is expected to be highly clinically effective. Checkpoint inhibitory receptors and their ligands are co-expressed on hematopoietic cells found in the leukemic milieu. Several distinct immunological mechanisms are likely to be engaged by antibody-based checkpoint blockade. Co-expression of multiple inhibitory receptors on hematopoietic cells offers an opportunity for combining blocking antibodies to achieve more effective therapy. Up-regulation of receptor/ligand expression in the leukemic milieu may provide a blood marker predictive of response. Finally, chemotherapy-induced up-regulation of PD-1 on T cells after conventional leukemia therapy creates a solid rationale for application of checkpoint blockade as a follow-up therapy.     

Engraftment with chronic granulocytic leukemia cells in acute myeloid leukemia

A deliberate engraftment with nonirradiated chronic granulocytic leukemia (CGL) cells was performed in a patient with acute myeloid leukemia (AML) at a time when he was resistant to cytotoxic drug chemotherapy, pancytopenic and developed an infection. The CGL engraftment was confirmed by the presence of a Ph1-positive donor clone in the recipient's bone marrow and by the pattern of colony growth of the recipient's bone-marrow cells cultured in vitro. Bone marrow engraftment in the host helped in the resolution of infection and permitted the administration of further cytotoxic drugs, as a result of which a remission of AML occurred.     

急性髓系白血病与急性淋巴系白血病的蛋白质组比较研究

本研究通过对急性髓系白血病(AML)与急性淋巴系白血病(ALL)细胞比较蛋白质组分析,寻找亚型特异性的蛋白质表达谱。应用双向电泳分别分离AML不同亚型(M1、M2、M3)、ALL患者骨髓白血病细胞蛋白质,利用PDQuest 7.4软件分析双向电泳图谱差异蛋白质点,基质辅助的激光解析飞行时间质谱和生物信息学鉴定差异蛋白质。结果显示:经过电泳图谱分析得到21个差异蛋白质点,质谱鉴定提示15种蛋白有统计学意义。在AML中高表达的蛋白质包括髓过氧化物酶(MPO)、硫氧还蛋白依赖的过氧化物还原酶(PRDX3),钙网蛋白(CALR)、烯酰辅酶A水合酶ECH1等7种,在ALL中高表达的蛋白质包括ARHGDIB、肌动蛋白抑制蛋白1(PFN1)、肌动蛋白(ACTG1)等8种。结论:AML与ALL细胞存在差异蛋白质表达谱,这将有助于发现早期诊断的分子标志物及特异性治疗靶标。     

Response in acute myeloid leukemia

For many years, response to induction therapy in acute myeloid leukemia was classified as "complete response" (CR) or "no CR." The emphasis on CR reflected the proven ability of CR to extend survival, the outcome of primary interest to patients. Beginning with the adoption of complete response with incomplete platelet recovery (CRp), recent years have seen the acceptance of responses less than CR as beneficial. Although these responses denote that a drug is active, relatively little attention has been paid to the effect of such responses on survival. This article explores the effect of such responses on survival.     

Highly refractory acute myeloid leukemia

In this study we evaluated 103 patients suffering from acute myeloid leukemia (AML) who did not respond to induction chemotherapy and defined a sub-group of patients with highly refractory disease characterized by a persistence of more than 1 G/L blast cells in the peripheral blood between days 12 and 16 of the first induction cycle. Only seven patients (one female, six males) met these criteria. Their median age was 65 years (range 41-82 years). Four had de novo AML and three secondary AML. Cytogenetic analysis was performed in six patients: complex aberrations were detected in four patients and, unexpectedly, normal karyotypes were found in the other two. Analysis of multidrug-resistance factors revealed high co-expression of P-glycoprotein (P-gp) and lung resistance protein (LRP) in all four patients with highly refractory disease tested a finding in only 6% of patients with refractory disease and 3% of patients who achieved complete remission (CR) of disease. Furthermore, patients with highly refractory AML had substantially higher leukocyte counts than patients with refractory AML or CR, although this was not significant statistically. Overall, patients with highly refractory AML are characterized by a high incidence of complex cytogenetic aberrations and marked expression of drug transporters.     

T-cell lymphoblastic leukemia/lymphoma syndrome with eosinophilia and acute myeloid leukemia

This case represents an example of an unusual T-cell lymphoblastic leukemia/lymphoma syndrome associated with eosinophilia and myeloid malignancy in a young boy. This case is one of only five reported "leukemic" variants of the disease and demonstrates the importance of considering this poor prognostic diagnosis in pediatric acute lymphoblastic leukemia. This case also illustrates the importance of an interactive multidisciplinary approach to the laboratory evaluation of a leukemia patient.     

急性髓系白血病患者NPM1基因突变分析

目的研究成人急性髓系白血病（AML）患者的NPM1基因第12外显子突变的发生率及临床特征。方法采用PCR扩增产物直接测序法或毛细管电泳法检测101例成人AML患者（M0 1例，M1 17例、M2 25例、M3 23例、M4 7例、M5 25例、M6 3例）NPM1基因第12外显子的突变情况，了解NPM1基因突变阳性患者的临床特征。结果101例AML患者中共检出32例（31．7％）具有NPM1基因突变，其中M 01例、M1 9例、M2 7例、M4 2例、M5 13例。59例正常核型AML患者中27例（45．8％）发生NPM1基因突变，明显高于异常核型组（42例中5例，11．9％）（P〈0．001），且多见于M1和M5。NPM1基因突变型患者年龄相对较大（P〈0．05），外周血白细胞高，CD34和CD117表达水平低（P值均〈0．05）。对突变型患者的序列分析发现5种已知的NPM1基因突变类型（分别是A、B、D、NM、PM型突变），在1例患者中还发现了一种新型突变（暂命名为S型）。结论NPM1基因第12外显子的突变多见于正常核型AML患者，M1和M5患者更为多见，突变患者年龄较大，外周血白细胞数量高，并与CD34和CD117低表达相关。     

急性髓系白血病NPM1基因突变检测的临床意义

目的 探讨初诊急性髓细胞白血病(acute myeloid leukemia,AML)患者NPM1基因突变发生率及其与染色体核型和FAB亚型之间的关系,并分析NPM1基因的突变类型.方法 选取2004至2010年中日友好医院血液科99例初诊AML患者.采集患者骨髓标本,采用聚合酶链反应(polymerase chain reaction,PCR)扩增基因组DNA,并采用变性聚丙烯酰胺凝胶电泳(polyacrylamide gel electrophoresis,PAGE)和毛细管电泳两种方法对AML患者NPM1基因突变进行检测.应用G显带方法对其中72例初诊AML患者进行细胞遗传学分析,同时对10例NPM1突变阳性患者进行直接测序分析.NPM1插入突变在各亚型患者中发生率的比较采用x2检验.变性PAGE和毛细管电泳两种方法检测NPM1基因突变发生率的比较采用McNemar检验.结果 毛细管电泳法与变性PAGE法检测AML患者NPM1基因插入突变发生率分别为15％ (15/99)和11％ (11/99),差异无统计学意义(x2 =2.25,P＞0.05).NPM1插入突变在各亚型患者中发生率分别为:急性粒细胞白血病部分分化型(M2)(27％,8/30)、急性单核细胞白血病(M5)(32％,6/19)、红白血病(M6)(13％,1/8),差异无统计学意义(x2=1.06,P＞0.05),其余亚型未检测到NPM1插入突变.49例AML异常核型患者的NPM1插入突变发生率为4％ (2/49),23例正常核型患者的NPM1插入突变发生率为26％ (6/23),差异有统计学意义(x2=5.61,P＜0.05).10例NPM1基因插入突变均为A型突变(c.860_863 dupTCTG).突变导致NPM蛋白羧基末端读码框移,末尾7个氨基酸WQWRKSL被11个氨基酸CLAVEEVSLRK所代替.2例患者检测到内含子缺失突变,分别为IVS10-18_-15delCTTT和IVS10-17-15delTTT.结论 NPM1插入突变为AML患者常见基因改变,正常核型患者插入突变发生率高于异常核型患者.在NPM1基因内含子区发现2例缺失突变.     

染色质组装因子1,b亚单位在急性髓系白血病细胞中的表达研究

目的 探讨染色质组装因子1,b亚单位（chromatin assembly factor 1,subunit b,CAF1b）在急性髓系白血病（AML）中的表达情况及其特异性.方法 建立流式细胞术检测胞内蛋白的方法,测定AML细胞株KG1a及正常人、特发性血小板减少性紫癜（ITP）、AML、急性淋巴细胞白血病（ALL）、慢性粒细胞白血病慢性期（CML-CP）、多发性骨髓瘤（MM）患者的骨髓单个核细胞中CAF1b的表达情况,利用WinMDI 2.9软件分析流式数据,并行统计分析,比较之间的差异.结果 AML患者骨髓单个核细胞和KG1a细胞CAF1b的表达率分别为（21.40±2.91）％、（27.87±1.48）％,均明显高于正常人、ITP、ALL、CML-CP、MM患者（P均＜0.05）.结论 CAF1b在AML有核细胞中表达特异性增高,提示其可能为AML特异性肿瘤抗原.     

如何进行急性髓细胞白血病的临床科研

临床科研是提高临床诊疗水平的必由之路.通过临床科研,可以回答和解决临床科学问题,实现从临床-基础-临床的转化.我国的临床科研水平与欧美国家相比,尚存在较大差距,如何做好临床科研,一直是困扰我国临床医师的一个共性问题.尽快掌握临床科研的核心规律,对于缩小这一差距具有重要意义.本文作者拟聚焦自己从事的急性髓细胞白血病(AML)临床科研的经验和教训进行阐述,希望对同道提供帮助.