儿童急性淋巴细胞白血病应用小剂量左旋门冬酰胺酶的临床研究

目的　本文对ALL患儿 13例用小剂量L -asp的用药方法 ,以求达到既能减低或避免副作用的发生 ,又能保证L -asp作用的效果 .方法　对在接受L -asp化疗的ALL患儿 5 9例 195疗程 ,出现L -asp相关副作用后改用小剂量 (常规剂量 1/ 10 )L -asp治疗的 13例 ,观察其副作用发生的情况 .结果　应用常规剂量者有 13例 34例次出现L-asp相关副作用 ,发生率为 17.4 % ,其中 2例因出血性胰腺炎死亡 .改用小剂量L -asp治疗者 13例 4 2个疗程 ,发生L -asp相关副作用者 2例次 ,发生率为 4 .8% ,显著低于应用常规剂量L -asp者 . 6例曾经发生过L -asp严重副作用的患儿在我科持续系统治疗 ,均未再次发生类似或其他L -asp副作用 ,CCR时间为 15 31± 14 0天 ,中位CCR时间为135 8天 .结论　对曾发生L -asp副作用的病例应用小剂量L -asp是安全有效的 .为预防L -asp相关副作用的发生 ,特别是已发生L -asp相关副作用的ALL患儿能继续应用L -asp治疗提供了科学的依据和可行的方法 .     

急性淋巴细胞白血病患者静注门冬酰胺酶后脑脊？…

对１４例儿童急性淋巴细胞白血病患者,在使用不同剂量左旋门冬酰胺酶前后检测了脑脊液中门冬酰胺的浓度,发现有７１．４％的患者脑脊液中在应用左旋门冬酰胺酶后无门冬酰胺可测到,肿瘤细胞缺乏门冬酰胺而不能合成蛋白质;因此应用不同剂量的左旋门冬酰胺酶均可抑制颅内脑组织白血病细胞的生长繁殖,对于中枢神经系统白血病的药理作用是肯定的。     

急性淋巴细胞白血病患者静注门冬酰胺酶后脑脊液门冬酰胺水平

对14例儿童急性淋巴细胞白血病患者,在使用不同剂量主旋门冬酰胺酶前后检测了脑脊液中门冬酰胺的浓度,发现有71．4％的患者脑脊液中在应用左旋门冬酰胺酶后无门冬酰胺可测到．肿瘤细胞缺乏门冬酰胺而不能合成蛋白质;因此应用不同剂量的左旋门冬酰胺酶均可抑制颅内脑组织白血病细胞的生长繁殖,对于中枢神经系统白血病的药理作用是肯定的．     

急性淋巴细胞白血病患儿化疗中L-ASP的副作用及对策

左旋门冬酰氨酶（简称L-ASP）是儿童急性淋巴细胞性白血病（急淋）化疗中的常用药和关键药，但是多种多样的副作用常常妨碍急淋患儿按计划进行化疗，我们对2001年-2005年收治的21例急性淋巴细胞性白血病患儿，针对不同的化疗反应，给予相应的临床干预措施，取得良好的效果，现报道如下。     

左旋门冬酰胺酶与盐霉素联合作用对急性T淋巴细胞白血病Jurkat细胞株增殖凋亡的影响

 目的：研究左旋门冬酰胺酶（L-asparaginase,L-ASP）与盐霉素（salinomycin,Sal）联合作用对急性T淋巴细胞白血病Jurkat细胞株增殖和凋亡的影响及其机制。方法：CCK-8试剂盒检测细胞增殖情况;Western blotting方法检测凋亡相关蛋白Bcl-2、caspase-3、caspase-8、caspase-9及细胞色素C表达的变化;流式细胞术分析各实验组细胞凋亡率之间的差别。结果：不同浓度的L-ASP和Sal单独处理Jurkat细胞株后均显示出明显的增殖抑制作用,L-ASP的IC50为812 IU/L,Sal 的IC50为0.75 μmol/L。而两药联合使用的增殖抑制作用更显著（P<0.05）;合用指数计算公式结果显示两药为协同作用。Western blotting 显示联合用药组与L-Asp、Sal单独处理组相比,Bcl-2蛋白表达明显减少,caspase-3、caspase-8、caspase-9和胞浆细胞色素C水平明显增高;干预48 h后行流式细胞术检测结果显示L-ASP（25 IU/L）单独处理组和Sal（0.5μmol/L）单独处理组细胞凋亡率分别为（7.11±0.23）%和（25.43±047）%,与对照组（6.67±0.13）%比较差别有统计学意义（P＜0.05),联合用药组细胞凋亡率（39.12±1.97）%分别与L-ASP、Sal单独处理组比较,差别有统计学意义（P＜0.05)。结论：左旋门冬氨酸酶与盐霉素联合作用于Jurkat细胞具有协同抑制增殖和诱导凋亡的作用。     

门冬酰胺酶对白血病患儿静脉血栓形成的研究进展

门冬酰胺酶在联合化疗中的应用使儿童急性淋巴细胞性白血病成为可治愈的恶性肿瘤。但ASP导致血栓形成可影响患者化疗进程,降低化疗缓解率。静脉血栓形成的发病率在1%~36%,主要取决于患者年龄、治疗方案、血栓筛检方法的不同。血栓形成的部位主要在上肢静脉,尤其是中心静脉导管。ASP导致血栓形成的机制是通过降低AT-Ⅲ水平,及激活血小板和内皮细胞。年龄、中心静脉导管、激素及遗传因素均是影响血栓发生的高危因素。预防性使用AT-Ⅲ或LWMH可降低静脉血栓形成的风险。新型口服抗凝药物,是凝血酶或Xa因子直接抑制剂,其抗凝效果不依赖AT-Ⅲ水平,由此推测,新型抗凝剂比传统抗凝剂在预防门冬酰胺酶相关性血栓形成更为有效和更便于临床应用。     

80例儿童急性淋巴细胞白血病的染色体分析

目的与方法本文对80例儿童急性淋巴细胞白血病（急淋）进行了细胞遗传学研究。结果发现正常核型为50%,染色体数量异常占40%,结构异常的染色体包括t（9;22）（q34;q11）,（8;14）（q24,q32）,6q占10%等。结论探讨认为细胞形态学,免疫表型和细胞遗传学的联合分析（MIC）有助于儿童急淋的诊断和分型,尤其细胞遗传学对于儿童急性淋巴细胞白血病的诊断和预后判断具有重要意义。     

中剂量阿糖胞苷治疗小儿急性淋巴细胞白血病不良反应观察

阿糖胞苷（Ara—C）于1959年合成,是细胞周期特异性抗肿瘤药物,1968年应用于临床,被广泛应用于白血病及其他恶性肿瘤的化学治疗。上世纪80年代开始广泛用于儿童急性白血病的治疗,迄今已有30余年的历史。普通剂量的阿糖胞苷治疗儿童急性白血病不良反应轻微,耐受性较好。而在90年代提出的中、大剂量阿糖胞苷化疗方案,提高了治疗的缓解率,但也增加了不良反应的发生,现将我科应用中剂量阿糖胞苷治疗儿童急性淋巴细胞白血病不良反应总结如下。     

大剂量甲氨蝶呤治疗急性淋巴细胞白血病的不良反应分析

目的：探究大剂量甲氨蝶呤在治疗急性淋巴细胞白血病中产生的不良反应。方法选取我院收治的50例急性淋巴细胞白血病患者为研究对象,对其行大剂量甲氨蝶呤治疗联合米非司酮治疗,观察患者发生的不良反应情况。结果大剂量甲氨蝶呤治疗急性淋巴细胞白血病常见的不良反应包括胃肠道反应、骨髓轻度抑制、肝功能损害、口腔溃疡等。结论大剂量甲氨蝶呤用于急性淋巴细胞白血病的治疗过程中容易产生不良反应,应当早发现早控制,并规范亚叶酸钙在救治过程中的使用剂量,可将不良反应降到最低。     

急性淋巴细胞白血病浸润牙龈1例

患者男性 ,30岁 ,在无任何诱因下出现左上颌牙龈包块2个月。检查 :贫血貌 ,颌下可触及肿大淋巴结 ,5 6 78颊侧面有一 5ｃｍ× 4ｃｍ× 2 5ｃｍ大小的肿块 ,表面呈菜花状 ,有糜烂。实验室检查 :Ｈｂ 6 6ｇ/Ｌ ,ＷＢＣ 2 4× 10 9/Ｌ ,Ｐｌｔ 190×10 9/Ｌ ,Ｌ 0 37,Ｎ 0 6 0 ,骨髓象增生明显活跃 ,淋巴系统显著增生 ,其中原幼淋占 0 6 5。临床初步诊断 :左上颌牙龈白血病浸润。遂活检左上颌牙龈包块以进一步证实。病理检查　灰白组织一块 2ｃｍ× 1 5ｃｍ× 1ｃｍ ,切面灰白 ,质细嫩 ,呈鱼肉状。镜检 :牙龈黏膜下方为弥漫浸润的肿瘤性原…     

Leukemic Blasts with the Paroxysmal Nocturnal Hemoglobinuria Phenotype in Children with Acute Lymphoblastic Leukemia

It has been proposed that genomic instability is essential to account for the multiplicity of mutations often seen in malignancies. Using the X-linked PIG-A gene as a sentinel gene for spontaneous inactivating somatic mutations, we previously showed that healthy individuals harbor granulocytes with the PIG-A mutant (paroxysmal nocturnal hemoglobinuria) phenotype at a median frequency (f) of ∼12 × 10⁻⁶. Herein, we used a similar approach to determine f in blast cells derived from 19 individuals with acute lymphoblastic leukemia (ALL) and in immortalized Epstein-Barr virus–transformed B-cell cultures (human B-lymphoblastoid cell lines) from 19 healthy donors. The B-lymphoblastoid cell lines exhibited a unimodal distribution, with a median f value of 11 × 10⁻⁶. In contrast, analysis of the f values for the ALL samples revealed at least two distinct populations: one population, representing approximately half of the samples (n = 10), had a median f value of 13 × 10⁻⁶, and the remaining samples (n = 9) had a median f value of 566 × 10⁻⁶. We conclude that in ALL, there are two distinct phenotypes with respect to hypermutability, which we hypothesize will correlate with the number of pathogenic mutations required to produce the leukemia.For a few sentinel genes, such as HPRT,^1,2, GPA^3–5 XK,⁶ HLA,⁷ and PIG-A,⁸ it is possible to use a phenotypic screen to quantitate the frequency (f) of spontaneously arising mutants in blood cells from healthy individuals. In these models, f values generally range from 1 × 10⁻⁶ to >60 × 10⁻⁶, depending on the sentinel gene and the age of the individual. Such estimates are critical for quantitative models of carcinogenesis. For example, considering that mutations in n different oncogenes or tumor suppressor genes are required for the development of malignancy, if each one were to occur independently, then the probability of n mutations coinciding in the same cell should approximate $\bar{f}$ⁿ, where $\bar{f}$ represents the geometric mean of the frequencies for the different oncogenic mutations. Since the adult body has <10¹⁴ cells, it has been argued that given these measured values for $\bar{f}$, it would be impossible for malignancy ever to occur if n > 2 unless spontaneous mutation rates were to somehow increase during the process of malignant transformation.^9,10Hypermutability could result from environmental mutagenesis or from genetic or epigenetic inactivation of repair genes. Abnormalities in the expression or fidelity of DNA polymerases and/or DNA repair genes^10,11 could also result in hypermutability. In support of this model, results from cancer genome sequencing projects have generally demonstrated a surprisingly high number of mutations.^12–14 However, mutations in repair genes or polymerases have not been commonly found. An alternative model to account for the multiplicity of mutations in cancer in the absence of hypermutability would involve successive rounds of clonal selection. Here, each oncogenic mutation would result in a partial growth advantage in a dividing premalignant cell population. According to this model, we might not expect to see a high frequency of phenotypic variants using a sentinel gene that is not itself an oncogene or a tumor suppressor gene.To evaluate these models, we considered it important to investigate whether there is evidence of hypermutability in ex vivo leukemic blasts. However, in applying a phenotypic screen for rare mutants in a leukemic blast population, we are limited by three considerations: i) for some of the sentinel genes mentioned previously herein (eg, XK and GPA), mutants can be detected only in red blood cells; ii) for HPRT, the cells must grow well in vitro, which ex vivo blast cells do not readily do; and iii) for autosomal genes, the effect of a loss of function mutation on one chromosome may be complemented by the unmutated allele on the homologous chromosome. For a few autosomal genes that have well-characterized polymorphic alleles (eg, HLA and GPA), it is possible to identify spontaneous loss of one allele—but only in cells from certain individuals who have a specific compound heterozygote genotype.PIG-A¹⁵ does not have these limitations and has several advantages as a sentinel gene for spontaneous somatic mutations. Because PIG-A is X-linked (as are HPRT and XK), a single inactivating mutation can produce the mutant phenotype owing to lyonization in females and hemizygosity in males. PIG-A has been well characterized owing to its association with paroxysmal nocturnal hemoglobinuria (PNH), and it is known that a broad spectrum of mutations can inactivate the gene,^16,17 providing a model for the inactivation of tumor suppressor genes and many of the point mutations that would activate oncogenes. We and others have demonstrated occult populations of cells with the PIG-A mutant (PNH) phenotype and genotype in diverse cell types, including granulocytes,⁸ lymphocytes,^18,19 human B-lymphoblastoid cell lines (BLCLs),^20,21 and marrow progenitors from normal donors,²² as well as cell lines derived from neoplasms.²³ Animals also harbor rare populations of spontaneously arising blood cells with the PIG-A mutant phenotype, and the frequency can be shown to increase as a result of mutagen exposure, as recently reviewed.²⁴A further advantage of using PIG-A as a sentinel gene is that its inactivation confers loss from the cell surface of all proteins that require glycosylphosphatidylinositol (GPI), resulting in a phenotype that can be detected by flow cytometry without a requirement for in vitro cell growth. PIG-A is widely expressed, and GPI is present in diverse cell types, including primitive hematopoietic cells such as leukemic blasts. In addition, antibodies specific for more than one GPI-linked protein can be used simultaneously, along with the fluorescent aerolysin (FLAER) reagent,²⁵ which binds to the GPI structure directly, to maximize the specificity of any assay. In a previous study using PIG-A, we demonstrated hypermutability in many but not all cell lines derived from hematologic malignancies.²⁶ Herein, we applied this approach to determine whether hypermutability can be demonstrated in populations of blasts from patients with ALL.     

急淋白血病患儿化疗期间全身性炎症反应综合征与预后的分析

目的探讨急性淋巴细胞白血病(ALL,急淋)患儿化疗期全身性炎症反应综合征(SIRS)的发生、发展与预后的关系.方法对ALL 42例,化疗135例次接受化疗期间发生SIRS 74例次分为粒缺组和非粒缺组.对符合SIRS诊断的在病程的第1天进行危重评分(PCIS评分)、儿童死亡危险评分(PRISM评分),并对多器官功能障碍综合征(MODS)的发生率和死亡率进行分析.结果①粒缺组PCIS评分低于非粒缺组(p＜0.05);粒缺组PRISM评分、MODS发生率、死亡率均高于非粒缺组(p＜0.05).②符合SIRS诊断标准的项目越多,粒缺组PCIS评分越低(p＜0.05),其PRISM评分越高、MODS发生率、死亡率越高(p＜0.05).结论粒细胞缺乏、符合SIRS诊断标准的项目越多、合并MODS提示预后不良.     

急淋白血病患儿化疗期间全身性炎症反应综合征与预后的分析

目的探讨急性淋巴细胞白血病(ALL,急淋)患儿化疗期全身性炎症反应综合征(SIRS)的发生、发展与预后的关系.方法对ALL42例,化疗135例次接受化疗期间发生SIRS74例次分为粒缺组和非粒缺组.对符合SIRS诊断的在病程的第1天进行危重评分(PCIS评分)、儿童死亡危险评分(PRISM评分),并对多器官功能障碍综合征(MODS)的发生率和死亡率进行分析.结果①粒缺组PCIS评分低于非粒缺组(p＜0.05);粒缺组PRISM评分、MODS发生率、死亡率均高于非粒缺组(p＜0.05).②符合SIRS诊断标准的项目越多,粒缺组PCIS评分越低(p＜0.05),其PRISM评分越高、MODS发生率、死亡率越高(p＜0.05).结论粒细胞缺乏、符合SIRS诊断标准的项目越多、合并MODS提示预后不良.     

Allogeneic Hematopoietic Cell Transplantation in Children with Relapsed Acute Lymphoblastic Leukemia Isolated to the Central Nervous System

Allogeneic hematopoietic cell transplantation (HCT) is the standard of care for pediatric patients with early medullary relapse of acute lymphoblastic leukemia (ALL). Most patients with isolated central nervous system (CNS) relapse have good outcomes when treated with intrathecal and systemic chemotherapy followed by irradiation to the neuroaxis. However, the role of HCT remains unclear for those patients with early isolated CNS relapse (<18 months) or who had high risk disease at diagnosis. We therefore compared the HCT outcomes of 116 children treated at the University of Minnesota from 1991 to 2006 with relapsed ALL involving the CNS alone (CNS, n = 14), the bone marrow alone (BM, n = 85), or both bone marrow and CNS (BM + CNS, n = 17). There were no significant differences among groups in age at diagnosis or transplant, length of first complete remission (CR1), remission status (CR2 versus ≥CR3), graft source, or preparative regimen. The incidence of acute GVHD was similar between groups. Patients with isolated CNS relapse had the lowest cumulative incidence of mortality following transplant (CNS: 0%, BM: 19%, BM + CNS: 29%, P = .03) and relapse (CNS: 0% BM: 30%, BM + CNS: 12%, at 2 years, P = .01) and highest leukemia-free survival (CNS: 91%, BM: 35%, BM + CNS: 46%, P < .01) at 5 years. Risk factors for poor survival were: T cell leukemia or BCR-ABL gene rearrangement, history of marrow relapse, and receipt of HLA-mismatched marrow. These data support the use of allogeneic HCT in the treatment of children with poor prognosis isolated CNS relapse.     

Transplantation Conditioning Regimens and Outcomes after Allogeneic Hematopoietic Cell Transplantation in Children and Adolescents with Acute Lymphoblastic Leukemia

Relapse is common after hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia (ALL). Although 1200 cGy total body irradiation (TBI) and cyclophosphamide (Cy) is the standard conditioning regimen, attempts to reduce relapse have led to the addition of a second chemotherapeutic agent and/or higher dose of TBI. We examined HSCT outcomes in patients age <18 years with ALL, in second or subsequent remission or in relapse at transplantation. Most transplantations were performed with the patient in remission. Patients received grafts from an HLA-matched sibling or unrelated donor. Four treatment groups were created: (1) Cy + TBI ≤ 1200 cGy (n = 304), (2) Cy + etoposide + TBI ≤ 1200 cGy (n = 108), (3) Cy + TBI ≥ 1300 cGy (n = 327), and (4) Cy + etoposide + TBI ≥ 1300 cGy (n = 26). Neither TBI > 1200 cGy nor the addition of etoposide resulted in fewer relapses. The 5-year probability of relapse was 30% for group 1, 28% for group 2, 35% for group 3, and 31% for group 4. However, transplantation-related mortality was higher (35% versus 25%, P = .02) and overall survival lower (36% versus 48%, P = .03) in group 4 compared with group 3. Our findings indicate that compared with the standard regimen, neither TBI > 1200 cGy nor the addition of etoposide improves survival after HSCT for ALL.