Clinical relevance of in vitro drug resistance testing in childhood acute lymphoblastic leukemia: The state of the art

Nowadays about two-thirds of children with acute lymphoblastic leukemia (ALL) can be cured with chemotherapy, but one-third die from the disease. The clinical response of leukemic cells to chemotherapy is roughly due to two factors: the effective drug levels reaching the cells and the resistance of these cells to the drugs. The clinical value of cellular drug resistance in children with ALL is not known. We developed an in vitro assay to study drug resistance in these children. In this article, the main results obtained with this MTT assay on samples from 137 children with ALL are summarized: (1) patients whose cells are resistant to several drugs at initial diagnosis have a poor prognosis; (2) relapsed leukemias show a considerable drug resistance which might partly explain the poor prognosis. Relapsed cases differ in their type and degree of resistance; (3) the poor outcome of high risk groups as defined by age and immunophenotype can partly be explained by specific patterns of drug resistance; (4) P-glycoprotein-mediated multidrug resistance is not an important cause of resistance in childhood ALL; and (5) no relation exists between the activities of the purine enzymes HGPRT, 5′NT, ADA, and PNP and drug resistance in childhood ALL. The conclusion is that in vitro drug resistance data have clinical relevance and can be used to develop more effective and less toxic treatment strategies in childhood ALL. © 1994 Wiley-Liss, Inc.     

A meta-analysis of the neurocognitive sequelae of treatment for childhood acute lymphocytic leukemia

BACKGROUND: Impaired neurocognitive functioning is one increasingly recognized long-term consequence of childhood ALL treatment. However, research findings have been inconsistent regarding the domains affected and the degree to which they are compromised. PROCEDURE: A comprehensive meta-analytic review of the long-term neurocognitive effects of childhood ALL was conducted. Studies were included if they were published in English, reported original quantitative data on the post-treatment neurocognitive functioning of childhood ALL patients in first remission and control groups, and used neurocognitive measures with adequate psychometric properties and published normative data. RESULTS: Data from 28 empirical studies yielding 13 effect sizes across nine domains were extracted and analyzed. All effects were negative (g = -0.34 to -0.71), demonstrating that ALL survivors consistently experienced significant deficits in intellectual functioning, academic achievement, and specific neurocognitive abilities compared to control groups. The role of potential moderators, including treatment with cranial irradiation, age at time of diagnosis, and time since treatment ended, was examined. However, no effects emerged as clearly and consistently moderated by these variables. CONCLUSIONS: The results from this meta-analysis suggest that declines in both global and specific areas of areas of neurocognitive functioning occur as a result of contemporary ALL treatment. Such deficits have significant implications for survivors' academic achievement and overall quality of life. Neurocognitive assessment plays a critical role in determining what remedial or specialized instruction is needed in childhood ALL survivors and should be included as a standard part of long-term follow-up care.     

Acute nonlymphocytic leukemia in 171 children

The initial features, response to therapy, complications, cause of death, and prognostic factors of 171 consecutive children with ANLL are described and compared to historical data for adults with ANLL and for children with ALL. Major differences between children and adults with ANLL include a higher frequency of CNS leukemia and a lower frequency of early deaths in the children. The most important differences between children with ANLL and ALL are the absence of a peak age of incidence in ANLL and the far better response to therapy in ALL. Among features present at 100,000/mm³ or above, and no palpable hepatomegaly had significantly longer survivals, while patients with platelet counts below 10,000/mm³ had significantly shorter survivals. The frequency and duration of remission were significantly better with three protocols used since 1968 than previously. However, even with these protocols, the results were far from satisfactory, with a complete remission frequency of 66%, a median duration of hematological remission of 6 months, and a median duration of survival of 10 months. The striking contrast of these results in childhood ANLL with current results in childhood ALL underscores the need for novel, imaginative therapeutic approaches for ANLL.     

ALL-XH-99方案治疗儿童急性淋巴细胞性白血病疗效分析

目的：由上海新华医院／上海儿童医学中心制定的治疗儿童急性淋巴细胞性白血病（ALL）的ALL-XH-99方案已在该院实施10年了。该文旨在评估应用此方案治疗儿童急性淋巴细胞性白血病（ALL）的疗效,并探讨儿童ALL的预后因素。方法：回顾分析1998年1月～2007年4月在该院采用ALL-XH-99方案治疗的儿童ALL的临床资料。该研究在ALL-XH-99方案的基础上作了一些小的修订,即对高危患儿也未给予颅脑放射治疗。采用Kaplan-Meier方法评估患儿的无事生存率（EFS）,组间患儿EFS差异用log-rank检验。采用逐步Cox比例风险模型分析ALL的预后因素。结果：115 例患儿得到了全程的ALL-XH-99方案治疗,其中低、中、高危患儿分别为62、12、41人。这115例患儿总的5年EFS率为（69.0±5.0）%,其中低危、中危、高危组5年的EFS率分别为(82.0±6.0)%、(77.0±15.0)% 和 (43.0±11.0)% （P< 0.01）。16例(13.9%)复发,复发的中位时间为17个月。所有病例均未采取颅脑放疗,中枢神经系统白血病复发率（2/115,1.7%）并未高于既往报道。多因素分析显示白血病危险分度、t(9;22)/bcr/abl融合基因和白细胞计数是儿童ALL独立的不利预后因素,其风险比例分别为1.867、3.397和2.236。结论：采用ALL-XH-99方案治疗儿童ALL疗效满意,取得了与发达国家类似的EFS率。t(9;22)/bcr/abl融合基因为儿童ALL最重要的不利预后因素。在强有力的系统化疗和鞘内注射条件下,对所有患儿可取消颅脑放疗以减少副作用。     

98-方案诊治儿童急性淋巴细胞白血病疗效和预后因素分析

目的探讨98-方案诊治儿童急性淋巴细胞白血病(ALL)的疗效和预后因素,以便进一步提高儿童ALL无事生存率(EFS)。方法回顾性分析1998年10月—2003年7月83例初诊儿童ALL临床资料,采用Kaplan Meier法评估各因素对患儿5年无事生存率(5-year EFS)的影响,组间患儿5-year EFS差异比较采用Log-Rank检验,COX比例风险回归模型分析各变量的独立预后价值。结果83例儿童ALL完全缓解(CR)率为96.4%,总体5-year EFS为(62.0±6.0)%。多因素分析表明泼尼松诱导试验不良是预后不良的独立因素,其相对危险度(RR)为1.577;而治疗顺从是预后良好的独立因素,其RR为0.443。泼尼松诱导试验高度敏感对预后不良预测的敏感度和特异度分别为67.9%和76.7%,泼尼松诱导试验高度敏感+敏感对预后不良预测的敏感度和特异度分别为94.3%和33.3%。结论采用98-方案治疗儿童ALL疗效满意,泼尼松诱导试验不良是预后不良的独立因素,泼尼松诱导试验高度敏感对预后不良预测的敏感度和特异度都比较高,治疗顺从是预后良好的重要因素。     

The pediatric preclinical testing program: description of models and early testing results

BACKGROUND: The Pediatric Preclinical Testing Program (PPTP) is an initiative supported by the National Cancer Institute (NCI) to identify novel therapeutic agents that may have significant activity against childhood cancers. The PPTP has established panels of childhood cancer xenografts and cell lines to be used for in vivo and in vitro testing. These include panels for Wilms tumor, sarcomas (rhabdomyosarcoma, Ewing sarcoma, and osteosarcoma), neuroblastoma, brain tumors (glioblastoma, ependymoma, and medulloblastoma), rhabdoid tumors (CNS and renal), and acute lymphoblastic leukemia (ALL). Here, we describe the characteristics of the in vivo tumor panels and report results for the in vivo evaluation of two standard agents, vincristine and cyclophosphamide. PROCEDURES: Solid tumors were grown subcutaneously in immune-deficient mice and tumor dimensions were measured weekly. ALL xenografts were inoculated intravenously and human CD45-positive cells were enumerated weekly. RESULTS: Vincristine-induced objective responses in 6 of 24 (25%) and cyclophosphamide-induced objective responses in 18 of 28 (64%) solid tumor models. Comparable assessments of high levels of activity for these two agents were obtained using a tumor growth delay (TGD) measure. Both agents induced regressions in each of the ALL models evaluated. CONCLUSIONS: We have established 51 solid tumor and 10 ALL in vivo models. The models identify vincristine and cyclophosphamide as having broad-spectrum activity. The PPTP tumor panels appear to generally recapitulate the activity of these agents against specific childhood cancers and to have the potential for identifying novel agents having significant clinical activity.     

Childhood relapsed acute lymphoblastic leukemia: Biology and recent treatment progress

Acute lymphoblastic leukemia (ALL) is the most frequent cancer in children. Despite remarkable improvement in the prognosis of childhood ALL over the past few decades, the treatment of relapsed ALL is still challenging. The prognosis of first ALL relapse is associated with time of relapse after initial therapy, sites of relapse, and immunophenotype. More recently, response to treatment, which is evaluated by assessment of minimal residual disease (MRD), has been found to be clinically significant in relapsed ALL as well as in the initially diagnosed disease. Utilizing these factors, risk‐oriented treatment stratification for first ALL relapse has been established. In the standard‐risk group for first ALL relapse, intensification of conventional ALL‐type therapy can provide a cure in approximately 70% of patients. It is important to assess MRD after reinduction therapy to determine the indications for stem cell transplantation in the standard‐risk group. In contrast, no standardized therapy has been established for the high‐risk group, which accounts for more than half of relapsed ALL patients. Recent studies have shed light on the clonal origin of relapsed ALL, which usually exists as a minor subclone at the time of initial diagnosis. Clonal selection and evolution take place during chemotherapy, resulting in distinct genetic and epigenetic characteristics of relapsed ALL, some of which are linked to drug resistance, a common and problematic feature of ALL after relapse. To overcome resistance to standard ALL‐type therapy, and considering the heterogeneous biological background of high‐risk relapsed ALL, innovative therapies using new agents are necessary.     

急性白血病、恶性淋巴瘤患儿大剂量阿糖胞苷治疗的药代动力学及代谢关键酶基因表达研究

目的 探索大剂量阿糖胞苷(HD-AraC)治疗儿童恶性血液肿瘤的药代动力学,以及代谢关键酶基因表达与临床疗效的关系.方法 应用高效液相色谱法测定HD-AraC治疗时血液和脑脊液中药物浓度;采用RT-PCR法检测3种白血病细胞株和48例急性白血病(AL)患儿骨髓细胞中脱氧胞苷激酶(dCK)和胞苷脱氨酶(CDA)基因表达,通过分析不同类型AL患儿,以及初治和复发患儿dCK和CDA mRNA表达差异,探讨dCK和CDA mRNA表达与疗效的关系.结果 ①HD-AraC治疗时血浆药物浓度可达到常规剂量Ara-C的50倍,脑脊液中药物浓度达到血浆浓度的10%;②不同类型儿童AL,以及初治和复发患儿的dCK mRNA表达强度差异有统计学意义,与临床疗效明显相关;③体外实验发现经Ara-C不同剂量和时间作用后,白血病细胞株的dCK和CDA mRNA表达没有变化.结论 HD-AraC治疗可明显提高血浆和脑脊液中药物浓度,是治疗儿童AL的有效疗法.dCKmRNA表达强弱可能为儿童AL远期疗效的重要影响因素之一.     

CD45+和CD45-儿童急性B淋巴细胞白血病的临床特征分析

目的探讨CD45抗原表达与儿童急性B淋巴细胞白血病(B-ALL)的临床相关性。方法利用多参数流式细胞术(FCM)以CD45/SSC设门对61例B-ALL患儿进行免疫分型检测;采用染色体核型分析和多重巢式RT-PCR技术进行染色体、融合基因分析。结果免疫表型分析显示CD45+组CD13、HLA-DR抗原表达明显高于CD45-组(P<0.05);CD45-组的融合基因主要为HOX11和E2A/PBX1,而CD45+组主要为TEL/AML1、MLL/AF9、HOX11;相关临床参数、染色体核型及疗效比较两组间差异均无显著性(P>0.05)。结论 CD45抗原的表达与否和B-ALL患儿的临床特征、染色体畸变、治疗效果无统计学相关性;CD45+组较CD45-组高表达CD13和HLA-DR。     

儿童Ph-like急性淋巴细胞白血病的研究进展

费城染色体样急性淋巴细胞白血病(Ph-like ALL)是一组基因表达谱与费城染色体阳性ALL(Ph~+ALL)相似的B-ALL(B-lineage ALL)亚群,涉及一系列细胞因子受体基因及激酶信号通路异常活化的相关基因改变,并常伴淋系发育相关转录因子异常。Ph-like ALL在高危组儿童B-ALL的比例高达15%,其临床特征与不良预后相一致。酪氨酸激酶抑制剂(TKIs)联合化疗显著改善儿童Ph~+ALL预后提示基于Ph-like ALL分子遗传学异常的精准靶向治疗具有良好的研究前景。该文结合近年Ph-like ALL的相关研究进展,对儿童Ph-like ALL的基因改变及发病机制、临床特征、诊断及治疗进行综述。     

Comparison of the antileukemic activity in vitro of dexamethasone and prednisolone in childhood acute lymphoblastic leukemia

It is generally assumed that prednisolone (PRD) and dexamethasone (DXM) have equal glucocorticoid activity if PRD is given at sevenfold higher doses. Results of clinical studies of childhood acute lymphoblastic leukemia (ALL) suggested that DXM is more potent relative to PRD than assumed. The purpose of this study was to determine the relative antileukemic activity of PRD phosphate and DXM phosphate in 133 untreated childhood ALL samples in vitro, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium-bromide (MTT) assay. There was a marked variation in antileukemic activity of both agents among the patient samples. The median LC50 (drug concentration lethal to 50% of the ALL cells) for PRD phosphate was 3.50 μM, for DXM phosphate 0.20 μM. The individually calculated ratios of the LC50 values for PRD and DXM phosphate showed a large range from 0.7 to >500, with a median of 16.2. This 16-fold difference could not be explained by differences between these glucocorticoids in stability, hydrolysis into unesterified drug, adhesion to the wall of the microculture plates, or protein binding. ALL cells were cross-resistant to PRD and DXM phosphate (correlation coefficient = 0.85, P < 0.000001). We conclude that the in vitro antileukemic activity of DXM phosphate is median 16-fold higher than that of PRD phosphate, which contrasts to the generally assumed factor of 7. Based on the higher potency of DXM, and its more favorable pharmacokinetics as reported in the literature, DXM may be preferred to PRD as the glucocorticoid in the treatment of ALL. © 1996 Wiley-Liss, Inc.     

Myelopoiesis in immunologically classified subgroups of childhood acute lymphocytic leukemia

Soft agar culture studies of 43 immunologically characterized patients with childhood acute lymphocytic leukemia (ALL) are presented. The immunologic subsets studied include “null”-cell, pre-B-cell, and T-cell leukemias. Abnormal myelopoiesis, including high peripheral blood and low marrow, colony-forming cell numbers, low colony-stimulating activity, and normal maturation of colony-forming cells in vitro was noted in each group as previously described for immunologically uncharacterized ALL. We conclude that immunologic subsets of childhood lymphoblastic leukemia cause similar abnormalities of myelopoiesis. Lack of differences in growth characteristics among immunologic subsets of ALL make it impossible to use this tissue culture technique in sub-classification of these leukemic disorders.     

BIM基因与儿童急性淋巴细胞白血病对糖皮质激素耐药的相关性

急性淋巴细胞白血病(ALL)是儿童时期最常见的恶性血液系统疾病。糖皮质激素作为ALL化疗方案中的主要用药,可通过多种途径诱导白血病细胞的凋亡,但仍有约10%的儿童ALL对糖皮质激素不敏感。研究发现糖皮质激素通过上调BIM基因表达介导ALL细胞的凋亡,BIM基因与儿童ALL对糖皮质激素耐药有关。本综述概括了近年关于儿童急性淋巴细胞白血病对糖皮质激素耐药相关研究,主要包括BIM基因及其表达产物在该过程中的作用。     

L-Asparaginase and steroids-associated hypertriglyceridemia successfully treated with plasmapheresis in a child with acute lymphoblastic leukemia

L-Asparaginase is an effective drug in childhood acute lymphoblastic leukemia (ALL) and it has become an important component of most childhood ALL regimens with administration in induction, intensification, and maintenance phases of treatment. L-Asparaginase is associated with side effects occurring either in a dose or time-dependent fashion or as hypersensitivity reactions. Some well-known toxicities in asparaginase-containing regimens are hypersensitivity/allergy and thromboembolic events. When asparaginase and steroids are used together, mild hyperlipemia is reasonably common. As some published studies show, this abnormality is often underdiagnosed. Hyperlipemia rarely constitutes a clinical problem; however, when triglyceride elevation is greater than 1000 mg/dL, the risk of pancreatitis is increased. We report the case of a young female presenting with acute severe hypertriglyceridemia (9250 mg/dL) during intensification phase of ALL, with neurologic symptoms but without the development of pancreatitis. She was successfully managed with 1 single run of plasmapheresis.     

Investigation of leukemia cells from children with common acute lymphoblastic leukemia for genomic sequences of the primate polyomaviruses JC virus, BK virus, and simian virus 40.

BACKGROUND: An infectious etiology for childhood acute lymphoblastic leukemia (ALL) has long been suspected, although the characteristics of the putative childhood ALL-inducing agent(s) remain a mystery. We describe the testing of ALL leukemia cells for the presence of DNA sequences of the polyomavirus family: JC virus, BK virus, and simian virus 40 (SV40). PROCEDURE: Cryopreserved leukemia cells from 25 children between 2 and 5 years of age at the time of diagnosis and classified as having "common" ALL (B-precursor ALL expressing the CD19 and CD10 surface antigens) were tested for the presence of polyomavirus sequences using standard PCR methods. RESULTS: Human beta-globin gene sequences were detected in 22 of 25 leukemia specimens. However, polyomavirus sequences were not detected in any of the 22 specimens with amplifiable DNA. CONCLUSIONS: The inability to detect JC virus, BK virus, and SV40 virus DNA sequences in any of the 22 specimens with amplifiable DNA suggests that that these members of the polyomavirus family are unlikely to be causally associated with most childhood ALL. Published 1999 Wiley-Liss, Inc.     

儿童急性淋巴细胞白血病常见融合基因的检测及意义

目的建立逆转录-巢式PCR检测融合基因的方法,检测4种常见融合基因在儿童急性淋巴细胞白血病中阳性率,并对阳性患儿进行初步临床资料分析。方法对收治的92例初发的急性淋巴细胞白血病(ALL)患儿,于化疗开始前抽取骨髓标本1.5～2.0 ml,采用巢式RT-PCR方法检测最常见的4种融合基因:TEL/AML1、E2A/PBX1、m-BCR/ABL和AF4/MLL。结果92例ALL患儿中TEL/AML1阳性21例,阳性率22.8%,占B细胞性ALL的24.7%(20/81例);6例E2A/PBX1阳性(6.5%),在前B细胞性ALL中占20.0%(3/15例);2例AF4/MLL阳性(2.2%),在婴儿ALL中占33.3%(2/6例);仅检测到1例m-BCR/ABL阳性(1.1%)。结论巢式RT-PCR方法是检测融合基因有效、敏感的方法。TEL/AML1在儿童ALL中阳性率最高,尤其是在B细胞性ALL中,该融合基因阳性的患儿病情较轻。     

Immuntherapeutische Behandlung therapierefraktärer und rezidivierter akuter lymphatischer Leukämien im Kindes- und Jugendalter

Acute lymphoblastic leukemia (ALL) represents the most frequent malignant disease in childhood and adolescence and offers a good prognosis with approximately 80% survival in first remission after polychemotherapy and radiotherapy. In addition,many children with relapsed or refractory ALL will still be cured by allogeneic hematopoietic stem cell transplantation (alloHSCT).However, therapeutic options are limited with a very poor prognosis in case of another relapse after alloHSCT.Here,immunotherapy strategies offer a promising alternative to another chemotherapy or second alloHSCT, which are mainly palliative and accompanied by high morbidity and mortality. Immunotherapy strategies aim at an improvement of the graft-versus-leukemia (GvL) effect.The therapeutic GvL effect is usually associated with graft-versus-host disease (GvHD).The definition of patients subgroups with an increased risk for relapse after alloHSCT gains growing importance for immunotherapy strategies.Promising approaches for separation of GvL-effect and GvHD after donor lymphocyte infusions, e.g. T-cell suicide gene therapy, will be described. Finally, vaccination strategies for ALL exist.     

Development of an effective treatment program for childhood acute lymphocytic leukemia: A preliminary report

The development of an effective therapeutic regimen for acute lymphocytic leukemia (ALL) of childhood is described. By careful surveillance of toxicity and efficacy, positive modifications of treatment strategy were achieved without resorting to classically randomized trials. The resultant protocol utilizes vincristine-prednisone induction followed by asparaginase consolidation, intensive intermittent combination maintenance chemotherapy with adriamycin as a major component, and cranial radiotherapy plus intrathecal methotrexate for central nervous system prophylaxis. Preliminary analysis suggests that this regimen may result in prolonged continuous complete remission in at least 80% of children with ALL.     

Challenges in the management of leukemia in India

Better understanding of cell kinetics and controlled trials with various combination chemotherapy has resulted in tremendous progress in the management of acute lymphocytic leukemia (All) of childhood. Results of management of ALL in India are poor. The possible causes for such poor results have been reviewed based upon an analysis of 110 cases of ALL seen over a period of 9 years. Means to improve these results are suggested.