Antitumor activity of bortezomib alone and in combination with TRAIL in human acute myeloid leukemia

Acute myeloid leukemia (AML) is a malignant disease characterized by abnormal proliferation of clonal precursor cells. Although different strategies have been adopted to obtain complete remission, the disease actually progresses in about 60-70% of patients. Bortezomib has been used in multiple myeloma and other lymphoid malignancies because of its antitumor activity. Here we examined the sensitivity of bone marrow cells from AML patients (34 patients: 25 newly diagnosed, 4 relapsed, 5 refractory) to bortezomib alone or in combination with TRAIL, a member of the TNF family that induces apoptosis in tumor cells while sparing normal cells. Bortezomib induced cell death in blasts from each patient sample. The cytotoxic effect was dose- and time-dependent (concentration from 0.001 to 10 microM for 24 and 48 h) and was associated with a downregulation of Bcl-xL and Mcl-1, an upregulation of TRAIL-R1, TRAIL-R2, p21, activation of executioner caspases and a loss of the mitochondrial membrane potential. Moreover, low doses of bortezomib primed TRAIL-resistant AML cells for enhanced TRAIL-mediated killing. These results suggest that a combination of proteasome inhibitors and TRAIL could be effective for treating AML patients, even patients who are refractory to conventional chemotherapy.     

Impact of MLL5 expression on decitabine efficacy and DNA methylation in acute myeloid leukemia

Hypomethylating agents are widely used in patients with myelodysplastic syndromes and unfit patients with acute myeloid leukemia. However, it is not well understood why only some patients respond to hypomethylating agents. We found previously that the effect of decitabine on hematopoietic stem cell viability differed between Mll5 wild-type and null cells. We, therefore, investigated the role of MLL5 expression levels on outcome of acute myeloid leukemia patients who were treated with decitabine. MLL5 above the median expression level predicted longer overall survival independent of DNMT3A mutation status in bivariate analysis (median overall survival for high vs. low MLL5 expression 292 vs. 167 days; P=0.026). In patients who received three or more courses decitabine, high MLL5 expression and wild-type DNMT3A independently predicted improved overall survival (median overall survival for high vs. low MLL5 expression 468 vs. 243 days; P=0.012). In transformed murine cells, loss of Mll5 was associated with resistance to low-dose decitabine, less global DNA methylation in promoter regions, and reduced DNA demethylation upon decitabine treatment. Together, these data support our clinical observation of improved outcome in decitabine-treated patients who express MLL5 at high levels, and suggest a mechanistic role of MLL5 in the regulation of DNA methylation.     

地西他滨治疗老年急性髓系白血病疗效及安全性分析

目的探讨以地西他滨为基础的化疗方案治疗老年急性髓系白血病(AML)的临床疗效及安全性。方法回顾性地分析2013年1月至2016年2月盐城市第三人民医院血液科收治的29例老年AML患者的临床资料,根据其是否使用地西他滨分为地西他滨组和传统方案组,对比评定疗效。结果地西他滨组和传统方案诱导后的完全缓解率分别为60.0%(6/10)和35.7%(5/14),差异有统计学意义(P0.05);同时两组的总生存期差异有统计学意义(44.9vs13.6个月,P0.05)。80.0%老年AML患者在使用以地西他滨为基础的化疗方案治疗过程出现不同程度的不良反应,仅30.0%的患者发生了Ⅲ~Ⅳ级不良反应,主要为中性粒细胞减少和血小板减少。结论地西他滨为基础的化疗方案有较高的缓解率,且可延长生存期。     

Second complete remission in an elderly patient with acute myeloid leukemia retreated with decitabine

A 67-year-old man with acute myeloid leukemia (AML) was treated with low-dose decitabine. He achieved a complete remission (CR) after two cycles of therapy, and he remained in remission during 1 year of treatment. He developed recurrent AML after discontinuation of decitabine. He was retreated with decitabine and again achieved a CR, which has been maintained for 6 months. This case demonstrates that durable responses can occur upon retreatment with decitabine.     

地西他滨单药或联合低剂量化疗治疗老年急性髓系白血病医院内感染的临床分析

目的分析地西他滨单药或联合低剂量化疗治疗老年急性髓系白血病医院内感染的临床特点及易感因素。方法回顾性分析2009年9月至2012年10月接受地西他滨单药或联合低剂量化疗治疗的10例老年急性髓系白血病患者医院内感染发生率、感染部位、致病菌和易感因素等。结果10例老年患者治疗后医院内感染率为70％,例次感染率为46．7％,感染部位以呼吸系统最多见（占52．4％）,致病菌以革兰阴性杆菌为主。化疗后骨髓抑制、粒细胞减少者感染率明显增高;与地西他滨联合低剂量化疗方案比较,地西他滨单药方案骨髓抑制、粒细胞减少发生率和医院内感染率降低。结论老年急性髓系白血病患者是医院内感染的易感人群,骨髓抑制、粒细胞减少是其易感因素。地西他滨单药方案治疗老年急性髓系白血病可降低医院内感染发生率。     

Antileukemic activity of rapamycin in acute myeloid leukemia

The mammalian target of rapamycin (mTOR) is a key regulator of growth and survival in many cell types. Its constitutive activation has been involved in the pathogenesis of various cancers. In this study, we show that mTOR inhibition by rapamycin strongly inhibits the growth of the most immature acute myeloid leukemia (AML) cell lines through blockade in G0/G1 phase of the cell cycle. Accordingly, 2 downstream effectors of mTOR, 4E-BP1 and p70S6K, are phosphorylated in a rapamycin-sensitive manner in a series of 23 AML cases. Interestingly, the mTOR inhibitor markedly impairs the clonogenic properties of fresh AML cells while sparing normal hematopoietic progenitors. Moreover, rapamycin induces significant clinical responses in 4 of 9 patients with either refractory/relapsed de novo AML or secondary AML. Overall, our data strongly suggest that mTOR is aberrantly regulated in most AML cells and that rapamycin and analogs, by targeting the clonogenic compartment of the leukemic clone, may be used as new compounds in AML therapy.     

Clinical outcome of treatment with a combined regimen of decitabine and aclacinomycin/cytarabine for patients with refractory acute myeloid leukemia

We conducted a clinical trial of low-dose decitabine plus aclacinomycin/cytarabine (AA) treatment (DAA) for 20 patients with refractory/relapsed de novo acute myeloid leukemia (AML) or AML transformed from myelodysplastic syndrome (MDS/AML) in order to examine its efficacy and tolerability. Additionally, P15^ink4b methylation status was analyzed (for 15 patients) pre- and post-DAA treatment, and in vitro drug sensitivity tests were performed for seven patients (AA or AA?+?decitabine) to explore the role of decitabine in this combination treatment regimen. A total of 11 patients (55.0?%) achieved complete remission (CR) after DAA treatment, including 7 of whom reached CR after only one treatment course. The other two patients achieved partial remission. The median overall survival (OS) was 10?months for all 20 patients. The median OS for those who achieved CR was significantly longer than that of patients with no response (NR; P?=?0.01). The treatment regimen was well tolerated, and there was no treatment-related mortality. The mean levels of P15^ink4b methylation decreased significantly in six patients who achieved CR, whereas very few changes in P15 ^ink4b methylation were detected for the five patients with NR following DAA treatment. The data from the methyl thiazolyl tetrazolium assays showed that the inhibition rates of AA and DAA for tumor cells were identical. We conclude that induction therapy with DAA for refractory/relapsed de novo AML or MDS/AML achieved high levels of CR and improved OS and demonstrated adequate tolerance. Moreover, the decitabine component of DAA may function through a demethylation effect.     

In vivo effects of decitabine in myelodysplasia and acute myeloid leukemia: review of cytogenetic and molecular studies

Low-dose demethylating agents such as 5-aza-2'-deoxycytidine (decitabine, DAC) and 5-azacytidine (azacitidine, Vidaza) have been explored for the treatment of myelodysplasia, acute myeloid leukemia, and hemoglobinopathies since the early 1980s, aiming to revert a methylator phenotype. Originally, the treatment rationale in hemoglobinopathies was to achieve demethylation of the hypermethylated and hence silent gamma-globin gene locus, thus reactivating synthesis of hemoglobin F (HbF). In myelodysplastic syndrome (MDS), cytogenetic analyses are mandatory for risk stratification and for monitoring response to drug treatment. The current knowledge regarding cytogenetic subgroups as predictors of response to low-dose decitabine in MDS as well as cytogenetic responses caused by demethylating agents is summarized in this review. Decitabine treatment is associated with a response rate that is higher in patients with high-risk cytogenetics (i.e., complex karyotype and/or abnormalities of chromosome 7) than in patients with intermediate-risk cytogenetics (two abnormalities or single abnormalities excluding 5q-, 20q-, and -Y). Following decitabine treatment of patients with abnormal karyotype, approximately one-third achieve a major cytogenetic response that can be confirmed by FISH analyses, while in two-thirds of patients, the abnormal karyotype persists but hematologic improvement may be observed during continued treatment. The most frequently studied gene in myelodysplasia is the cell cycle regulator p15(INK4b). Hypermethylation of p15(INK4b) in MDS is reversed during treatment with decitabine, resulting in reactivation of this gene. In hemoglobinopathies, treatment with demethylating agents leads to reactivation of fetal HbF (the gamma-globin gene locus also possibly being another target for reactivation in MDS), and thus, HbF may potentially act as surrogate marker for activity of decitabine. Other, thus far unidentified hypermethylated genes may also be targets for demethylating agents.     

预激方案治疗急性髓细胞白血病的临床研究

目的:探讨预激方案治疗急性髓细胞白血病的临床疗效。方法:对30例急性髓细胞白血病患者采用CAG方案化疗,如1疗程未获缓解,可接受第2疗程治疗。监测临床症状、体征血常规及骨髓细胞学检查。结果:总完全缓解率73.3%,感染发生率为50.0%,4例严重感染。化疗后外周血白细胞最低值平均为1.02(0.33～2.46)×109/L,低于1.0×109/L的中位时间为7(0～12)d。结论:预激方案治疗急性髓细胞白血病疗效肯定,不良反应小。     

Clinical implications of molecular markers in acute myeloid leukemia

The recently updated World Health Organization (WHO) Classification of myeloid neoplasms and leukemia reflects the fact that research in the underlying pathogenic mechanisms of acute myeloid leukemia (AML) has led to remarkable advances in our understanding of the disease. Gene mutations now allow us to explore the enormous diversity among cytogenetically defined subsets of AML, particularly the large subset of cytogenetically normal AML. Despite the progress in unraveling the tumor genome, only a small number of recurrent mutations have been incorporated into risk‐stratification schemes and have been proven to be clinically relevant, targetable lesions. We here discuss the utility of molecular markers in AML in prognostication and treatment decision making, specifically highlighting the aberrations included in the current WHO classification.     

高白细胞急性髓系白血病的临床分析

目的:探讨高白细胞急性髓系白血病(HAML)患者的临床特征、预后并与同期非高白细胞急性髓系白血病(NHAML)患者进行比较。方法:观察随访66例HAML(WBC≥100×109/L)病例(非M3型),分析并发症、早期死亡(early death,ED)、治疗反应、远期预后等,并与同期随机选择的202例NHAML(WBC<100×109/L)病例(非M3型)进行比较。结果:①HAML病例发生低钾血症、出凝血异常、感染、肺白细胞淤滞、脾脏肿大、淋巴结肿大等并发症的概率高于NHAML病例(P<0.05)。HAML病例FAB分型以M4/M5型为主。②HAML病例ED 4例(6.1%),ED与出凝血异常(P<0.01)、肺白细胞淤滞(P<0.01)、CNS白细胞淤滞症状(P<0.01)相关。③HAML病例CR率66.7%,且M4/M5型CR率低。HAML病例3年DFS率为45.7%,3年OS率为32.5%。完全缓解(CR)率与年龄、是否为M4/M5型相关(P<0.05)。3年无病生存率(DFS)与是否>50岁及染色体分组相关(P<0.01)。3年总生存率(OS)与是否CR相关(P<0.05)。NHAML病例CR率为90...     

急性髓细胞白血病端粒酶活性及临床意义

目的：探讨端粒酶活性在急性髓细胞白血病（ＡＭＬ）发生中的作用。方法：采用端粒重复序列扩增文件酶标法（ＴＲＡＰ－ＥＬＩＳＡ）,对３２例ＡＭＬ和非恶性血液系统疾病骨髓细胞端粒酶活性检测。结果：端粒酶活性在初发ＡＭＬ患者高于非恶性血液系统疾病患者（Ｐ〈０．０１）,ＡＭＬ初发期患者高于完全缓解期患者（Ｐ〈０．０５）,端粒酶生与体内白血病细胞数之间无显著相关性。结论：端粒酶活性的观察有助于疗效的判断。     

A phase 1 and pharmacodynamic study of depsipeptide (FK228) in chronic lymphocytic leukemia and acute myeloid leukemia

Preclinical studies with the histone deacetylase (HDAC) inhibitor depsipeptide (FK228) in chronic lymphocytic leukemia (CLL) and acute myeloid leukemia (AML) have demonstrated that it effectively induces apoptosis at concentrations at which HDAC inhibition occurs. We initiated a minimum effective pharmacologic dose study of depsipeptide, targeting an in vivo dose at which acetylation of histone proteins H3 and H4 increased by 100% or more in vitro. Ten patients with CLL and 10 patients with AML were treated with 13 mg/m(2) depsipeptide intravenously days 1, 8, and 15 of therapy. Neither life-threatening toxicities nor cardiac toxicities were noted, although the majority of patients experienced progressive fatigue, nausea, and other constitutional symptoms that prevented repeated dosing. Several patients had evidence of antitumor activity following treatment, but no partial or complete responses were noted by National Cancer Institute criteria. HDAC inhibition and histone acetylation increases of at least 100% were noted, as well as increases in p21 promoter H4 acetylation, p21 protein, and 1D10 antigen expression. We conclude that depsipeptide effectively inhibits HDAC in vivo in patients with CLL and AML, but its use in the current schedule of administration is limited by progressive constitutional symptoms. Future studies with depsipeptide should examine alternative administration schedules.     

地西他滨联合半量CAG方案治疗骨髓增生异常综合征-伴原始细胞增多和急性髓细胞白血病

目的:比较地西他滨(DAC)联合半程粒细胞集落刺激因子（G-CSF）联合小剂量阿糖胞苷（Ara-C）及阿克拉霉素（Acla）的预激化疗方案(CAG)与CAG方案治疗骨髓增生异常综合征伴原始细胞增多（MDS-EB）和急性髓系白血病(MDS/AML)患者的临床疗效及安全性。方法:回顾性分析21例MDS/AML患者临床资料，12例接受DAC-CAG（D-CAG）方案，9例接受CAG方案,诱导缓解后患者继续巩固化疗或进行造血干细胞移植。比较2组患者的总反应率(0RR)、总生存率(0S)及不良反应发生率。结果:2组的ORR分别为83.3%和66.7%，差异无统计学意义(P>0.05)。13例存活，6例死亡，2例失访，中位随访时问9(5～46)个月。2组2年OS率分别为66.7％、和55.6％，差异无统计学意义(P>0.05)。2组患者在治疗后，感染发生率、出血发生率、平均粒细胞缺乏时间、平均红细胞输注量、平均血小板输注量差异均无统计学意义(均P>0.05)。经抗感染及支持治疗后，21例患者均安全度过骨髓抑制期，无一例死亡。结论：D-CAG及CAG方案治疗MDS/AML均有较好的疗效，D-CAG方案诱导治疗有效率相对较高，不良反应与CAG方案相当，对患者长期生存的影响有待进一步观察。     

Clinical significance of genetic aberrations in secondary acute myeloid leukemia

The study aimed to identify genetic lesions associated with secondary acute myeloid leukemia (sAML) in comparison with AML arising de novo (dnAML) and assess their impact on patients' overall survival (OS). High‐resolution genotyping and loss of heterozygosity mapping was performed on DNA samples from 86 sAML and 117 dnAML patients, using Affymetrix Genome‐Wide Human SNP 6.0 arrays. Genes TP53, RUNX1, CBL, IDH1/2, NRAS, NPM1, and FLT3 were analyzed for mutations in all patients. We identified 36 recurrent cytogenetic aberrations (more than five events). Mutations in TP53, 9pUPD, and del7q (targeting CUX1 locus) were significantly associated with sAML, while NPM1 and FLT3 mutations associated with dnAML. Patients with sAML carrying TP53 mutations demonstrated lower 1‐year OS rate than those with wild‐type TP53 (14.3% ± 9.4% vs. 35.4% ± 7.2%; P = 0.002), while complex karyotype, del7q (CUX1) and del7p (IKZF1) showed no significant effect on OS. Multivariate analysis confirmed that mutant TP53 was the only independent adverse prognostic factor for OS in sAML (hazard ratio 2.67; 95% CI: 1.33–5.37; P = 0.006). Patients with dnAML and complex karyotype carried sAML‐associated defects (TP53 defects in 54.5%, deletions targeting FOXP1 and ETV6 loci in 45.4% of the cases). We identified several co‐occurring lesions associated with either sAML or dnAML diagnosis. Our data suggest that distinct genetic lesions drive leukemogenesis in sAML. High karyotype complexity of sAML patients does not influence OS. Somatic mutations in TP53 are the only independent adverse prognostic factor in sAML. Patients with dnAML and complex karyotype show genetic features associated with sAML and myeloproliferative neoplasms. Am. J. Hematol., 2012. © 2012 Wiley Periodicals, Inc.     

Clinical significance of Treg cell frequency in acute myeloid leukemia

This study was designed to investigate the clinical significance of peripheral blood CD4⁺ CD25⁺ CD127 low-regulatory T (T_reg) cells in acute myeloid leukemia (AML) patients. T_reg cells in the peripheral blood of 80 AML patients and 35 age-matched healthy controls were counted by flow cytometry. Correlations between the frequency of circulating T_reg cells and disease status, treatment outcome, or prognosis were evaluated. The percentages of T_reg cells in patients at diagnosis and during refractory/relapse were significantly higher than that in healthy controls. There was no significant difference in the percentages of T_reg cells between patients in remission and healthy controls. After six cycles of chemotherapy, the percentage of T_reg cells in patients who achieved complete remission was significantly lower than that in patients at diagnosis, but there was no difference in T_reg frequency between refractory/relapse patients and patients at diagnosis. T_reg cells in the peripheral blood of AML patients may play a suppressive role in host antitumor immune response. The frequency of T_reg cells in peripheral blood may thus be used as a biomarker for predicting sensitivity to chemotherapy and prognosis of AML patients. Additionally, T_reg number in peripheral blood could be used to monitor disease status and evaluate disease progression.     

Clinical implications of molecular genetic aberrations in acute myeloid leukemia

The role of different cytogenetic changes has been extensively evaluated in patients with acute myeloid leukemia (AML), and cytogenetic analysis of AML blasts is essential to form prognostic subgroups in order to stratify for the extent of therapy. Nevertheless, 40–45% of AML patients lack such cytogenetic markers, i.e., cytogenetically normal AML (CN-AML). In the past decade, different molecular aberrations were identified in AML and especially CN-AML can now be discriminated into certain prognostic subgroups. This review considers the latest advances to define the prognostic impact of molecular aberrations in AML and gives insights how such molecular markers can be applied for analysis of minimal residual disease. Furthermore, therapeutic implications as well as the potential role of new methodological techniques in analyzing expression patterns of AML blasts are discussed.     

增加地西他滨剂量治疗高危组骨髓增生异常综合征及急性髓系白血病20例分析

目的探讨增加地西他滨剂量治疗高危组骨髓增生异常综合征(MDS)及急性髓系白血病(AML)的疗效。方法收集2009年9月至2012年1月在苏州大学附属第一医院高危组MDS及AML患者20例,静脉滴注地西他滨20 mg/m2,每日1次,连用5 d治疗,然后行骨髓检查,根据患者骨髓增生程度、原始细胞数、骨髓小粒饱满情况,结合患者的一般情况、不良反应,酌情增加使用地西他滨,分析治疗1个疗程后缓解率和总反应率。结果 MDS患者1个疗程完全缓解(CR)+骨髓CR为3例(75%),总反应3例(75%);AML患者1个疗程CR+骨髓CR 3例(18.8%),总反应8例(50.0%),其中初治患者1个疗程CR+骨髓CR 1例(25.0%),总反应3例(75.0%),复发及难治患者1个疗程CR+骨髓CR 2例(16.7%),总反应5例(41.7%)。累积2年生存率为42%。结论剂量增加的地西他滨可被安全应用于高危组MDS及AML,1个疗程缓解率较高,值得进一步探索。