Preparation and evaluation of temperature sensitive liposomes containing adriamycin and cytarabine

Temperature sensitive liposomes (TSL) containing adriamycin (ADM) and cytarabine (Ara-C) were prepared. ADM and Ara-C were selected as model compounds of amphiphilic and hydrophilic drug, respectively. Encapsulation efficiency of ADM entrapped into TSL was about twice greater than that of Ara-C. It might be due to different polarity of the drugs. Lipid compositions of TSL had no effect on the encapsulation efficiency of drugs. Thermal behavior of TSL using a differential scanning calorimetry (DSC) was also investigated. Phase transition temperature (T_c) of TSL was dependent on the lipid compositions of TSL.ADM broadened thermogram of TSL but Ara-C did not. However, T_c of TSL was not changed by any drug. Release rate of drugs was highly dependent on temperature. The release profile of ADM was similar to that of Ara-C. The maximum release rate of drugs from TSL was occurred at the near T_c and observed at 39–41°C for DPPC (Dipalmitoylphosphatidylcholine) only, 52–54°C for DSPC (Distearoylphosphatidylcholine) only, 41–43°C for DPPC and DSPC (3∶1), and 43–45°C for DPPC and DSPC (1∶1), respectively. Effect of human serum albumin (HSA) on the release rate of ADM was investigated. HSA had no significant effect on the release of ADM below T_c. However, ADM release from TSL was increased at the near and above T_c. The HSA-induced leakage of drug may result from the interaction of liposomal constituents with HSA structure at the near T_c. From the fact that the release profiles of ADM from freshly prepared TSL and stored TSL for 1 week at 4°C was not changed, the TSL was considered to be stable for at least 1 week at 4°C. Based on these findings, TSL may be useful to deliver drugs to preheated target sites due to its thermal behaviors.     

骨髓增生异常综合征(附33例临床分析)

本文分析我院33例MDS病例的入院前诊断、病例类型、临床表现、血象及骨髓象资料,其中4例转变为急性白血病。     

Recombinant human interferonsα,β andγ reduce the antiproliferative action of cytarabine in K562 human myeloid leukaemia clonogenic cells

Summary The effects of recombinant human interferons , and (IFN) on the antiproliferative activity of cytarabine in K562 human myeloid leukaemia clonogenic cells were studied in an agar capillary microassay. The addition of IFN- did not affect the antiproliferative activity of cytarabine in K562 cultures treated with low concentrations of cytarabine (10–50 nM), whereas in those treated with high concentrations (100–150 nM) IFN increased the IC₅₀ of cytarabine on day 5 from 102 nM to 214 nM, i.e., cytarabine combined with IFN was about two-fold less potent than cytarabine alone. Similarly, low concentrations of IFN and IFN did not affect the antiproliferative activity of cytarabine on K562 colonies, but high concentrations of these two interferons: 4×10³ U/ml and 10⁴ U/ml respectively, increased the IC₅₀ of cytarabine on day 5 to 304 nM and to 316 nM respectively, i.e. cytarabine combined with IFN or IFN was about threefold less potent than cytarabine alone. The evaluation of the present negative interactions of interferons with cytarabine is warranted in fresh cells from myeloid leukaemia patients in primary culture.Abbreviation IFN interferon     

阿糖胞苷纳米粒的制备及其释药规律研究

采用乳化聚合法制备阿糖胞苷纳米粒，研究其体内外释药特性。结果表明阿糖胞苷纳米粒体外释药规律符合双指数方程，有明显的缓释作用。在家兔体内的药物动力学过程符合二室模型，与阿糖胞苷注射剂相比，t1／2β和MRT延长，CL降低，表明阿糖胞苷纳米粒可显著延长阿糖胞苷在体内存留时间，具有明显的缓释特征。     

Cerebral disseminated coagulation

Summary The distribution of cytarabine in the ventricular CSF was studied after lumbar intrathecal administration. In the ventricular fluid peak concentrations up to 1.5×10^–4 M (37 g/ml) were achieved 4–8 h after lumbar injection of cytarabine of 45 mg/m². The concentration of cytarabine decreased slowly with a half-time of 2.16 h thus providing therapeutic concentrations in the cerebral ventricles for more than 24 h.

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Zusammenfassung Die Verteilung von Cytosinarabinosid nach lumbaler intrathekaler Injektion im ventrikulären Liquor cerebrospinalis wurde untersucht.Nach lumbaler intrathekaler Injektion von 45 mg Cytosinarabinosid (Alexan®) pro m² Körperoberfläche wurde im ventrikulären Liquor eine Höchstkonzentration von 1,5×10^–4 M (37 g/ml) 4–8 h nach Applikation erreicht. Die Konzentration von Cytosinarabinosid im ventrikulären Liquor fiel langsam mit einer Halbwertszeit von 2,16 h ab. Bei lumbaler Applikation wurden bei dieser Untersuchung therapeutische Konzentrationen von Cytosinarabinosid in den cerebralen Ventrikeln für mehr als 24 h erreicht.

     

中剂量阿糖胞苷联合米托蒽醌及依托泊甙巩固治疗对难治复发性AML患儿的疗效及安全性

【摘要】目的 探讨中剂量阿糖胞苷联合米托蒽醌及依托泊甙巩固治疗对难治复发性急性髓系白血病（AML）患儿的疗效及安全性。方法 选取2008年12月～2012年12月我院收治的行阿糖胞苷联合米托蒽醌、依托泊甙巩固治疗的难治复发性AML患儿96例作为研究对象,采用回顾性分析法分析所有患儿的临床及随访资料,根据阿糖胞苷使用剂量的不同将其分为低剂量组、中剂量组和高剂量组3组,每组各32例,治疗结束后分析并比较3组患儿近期和远期临床疗效,并记录3组患儿治疗过程中不良反应的发生情况。结果 近期临床总有效率3组相比较差异均无统计学意义（P＞0.05）,且所有部分缓解的患儿中8例患儿进行骨髓移植治疗后治愈,余42例继续采用药物进行治疗;3组患儿5年总生存率（OS）比较差异有统计学意义（P＞0.05）,中剂量组和高剂量组患儿5年OS均高于低剂量组（P＞0.05）,但中剂量和高剂量组5年OS比较差异无统计学意义（P＞0.05）,3组患儿其5年无事件生存年率（EFS）比较差异均无统计学意义（P＞0.05）;3组患儿在骨髓抑制和心脏毒性的不良反应方面比较差异无统计学意义（P＞0.05）,但中剂量组和高剂量组患儿其感染、胃肠道反应以及肝肾功能损伤的不良反应发生率均显著高于低剂量组,且高剂量组患儿胃肠道和肝肾功能损伤的不良反应发生率均高于中剂量组患儿,组间比较差异均有统计学意（P＞0.05）。结论 中剂量阿糖胞苷联合米托蒽醌及依托泊甙巩固治疗对难治复发性AML患儿具有较好的临床疗效和较低的毒副反应,存在一定的安全性,可作为临床上治疗AML患儿的首选治疗方案。     

Obatoclax potentiates the cytotoxic effect of cytarabine on acute myeloid leukemia cells by enhancing DNA damage

Resistance to cytarabine and anthracycline‐based chemotherapy is a major cause of treatment failure for acute myeloid leukemia (AML) patients. Overexpression of Bcl‐2, Bcl‐xL, and/or Mcl‐1 has been associated with chemoresistance in AML cell lines and with poor clinical outcome of AML patients. Thus, inhibitors of anti‐apoptotic Bcl‐2 family proteins could be novel therapeutic agents. In this study, we investigated how clinically achievable concentrations of obatoclax, a pan‐Bcl‐2 inhibitor, potentiate the antileukemic activity of cytarabine in AML cells. MTT assays in AML cell lines and diagnostic blasts, as well as flow cytometry analyses in AML cell lines revealed synergistic antileukemic activity between cytarabine and obatoclax. Bax activation was detected in the combined, but not the individual, drug treatments. This was accompanied by significantly increased loss of mitochondrial membrane potential. Most importantly, in AML cells treated with the combination, enhanced early induction of DNA double‐strand breaks (DSBs) preceded a decrease of Mcl‐1 levels, nuclear translocation of Bcl‐2, Bcl‐xL, and Mcl‐1, and apoptosis. These results indicate that obatoclax enhances cytarabine‐induced apoptosis by enhancing DNA DSBs. This novel mechanism provides compelling evidence for the clinical use of BH3 mimetics in combination with DNA‐damaging agents in AML and possibly a broader range of malignancies.     

Adult patients with t(8;21) acute myeloid leukemia had no superior treatment outcome to those without t(8;21): a single institution’s experience

Clinical features and treatment outcome of 31 patients over 16 years of age with t(8;21) acute myeloid leukemia (AML) were compared with 60 patients without t(8;21). Among 31 patients with t(8;21), 15 patients were classified as AML-M2 and 11 and 5 patients as AML-M4 and M1, respectively. Of these patients, 28 patients (90.3%) achieved complete remission and 22 patients received consolidative treatment: intermediate-dose cytarabine (IDAC) 11, high-dose cytarabine (HDAC) 6, and allogeneic bone marrow transplantation (BMT) 5. When compared with patients without t(8;21), we could not demonstrate better treatment outcome for t(8;21) AML [median event-free survival (EFS) and overall survival (OS) 10.3 and 12.5 months in AML with t(8;21) vs 11.5 and 15.6 months in AML without t(8;21)]. In the t(8;21) AML group, patients who received HDAC consolidation did not show superior treatment outcome to those who received other consolidative treatment [median EFS: IDAC 11.9 months vs HDAC 9.2 months vs allogeneic BMT 38.1 months (P=NS) and median OS: IDAC 17.8 months vs HDAC 12.0 months vs allogeneic BMT 47.3 months (P=NS)]. Similar treatment outcome between patients with and without t(8;21) and non-superior treatment outcome of HDAC consolidative chemotherapy in the t(8;21) AML group in our study is contradictory to previous reports.These two authors equally contributed to this study: K.-W. Lee and I. S. ChoiSupported by a grant CRI-01-07 from the Cancer Research Institute, Seoul National University College of Medicine, and a grant 05-2001-002 from the S.N.U.H. Research Fund     

阿糖胞苷、阿柔比星联合粒细胞集落刺激因子治疗骨髓增生异常综合征的临床研究

目的 探讨阿糖胞苷(Ara-C)、阿柔比星(Acla)联合粒细胞集落刺激因子(G-CSF)治疗骨髓增生异常综合征(MDS)的临床疗效及安全性.方法 选择2011年1月至2013年1月,深圳市第四人民医院收治的初治MDS患者56例为研究对象.按照随机数字表法将其分为研究组(n=28)与对照组(n=28).研究组予以Ara-C、Acla联合G-CSF治疗,对照组按照标准化方案治疗.对两组的临床疗效、外周血常规结果及骨髓细胞原始比例、不良反应发生情况、巩固及维持治疗及生存情况进行统计学分析.本研究征得受试对象的知情同意,并与之签署临床研究知情同意书.两组患者的年龄、性别构成比、病程、疾病类型构成比及危险分型构成比与治疗前白细胞计数、血小板计数、血红蛋白(Hb)水平、中性粒细胞(Neut)计数及骨髓原始细胞比例等一般临床资料比较,差异均无统计学意义(P＞0.05).结果 ①研究组完全缓解(CR)率、治疗总有效率分别为50.0％(14/28)与82.1％(23/28),均显著高于对照组的32.1％(9/28)与53.6％(15/28),差异均有统计学意义(P＜0.05).②治疗后,研究组患者白细胞计数、血小板计数、Hb水平及Neut计数均显著高于对照组,骨髓原始细胞比例显著低于对照组,差异均有统计学意义(P＜0.05).治疗后,研究组组内白细胞计数、血小板计数、Hb水平及Neut计数较治疗前,均显著提高,骨髓原始细胞比例则显著下降,差异均有统计学意义(P＜0.05).治疗后,对照组组内白细胞计数与治疗前比较,差异无统计学意义(P＞0.05),而血小板计数、Hb水平及Neut计数则均较治疗前显著提高,骨髓原始细胞比例显著下降,差异均有统计学意义(P＜0.05).③研究组Ⅲ～Ⅳ级骨髓抑制、肺部感染、口腔溃疡及胃肠道等不良反应发生率均显著低于对照组,差异均有统计学意义(x2=12.847,17.044,7.212,14.684;P＜0.05).④研究组急性髓细胞白血病(AML)转化率(14.3％,4/28)显著低于对照组(25.0％,7/28),且差异有统计学意义(P＜0.05);研究组患者中位总体生存时间(22.0个月)较对照组(18.2个月)显著延长,差异有统计学意义(P＜0.05).结论 应用Ara-C、Acla联合G-CSF治疗MDS,治疗疗效显著,不良反应较少.因本研究纳入样本量较小,该方案是否为安全、可靠的治疗方案而值得临床推广应用,尚需多中心、大样本的前瞻性随机对照试验进一步研究证实.     

丙戊酸联合伏立诺他增强阿糖胞苷对人Dami白血病细胞株杀伤作用的机制研究

目的探讨丙戊酸(VPA)联合伏立诺他(SAHA)增强阿糖胞苷(Ara-c)对人Dami白血病细胞株的杀伤作用,并探讨其分子学机制。方法设空白对照组、Ara-c组、VPA组、SAHA组、VPA+Ara-c组、SAHA+Ara-c组,VPA+SAHA+Ara-c组,分别作用于对数生长期的Dami白血病细胞,MTT比色法检测药物对细胞的生长抑制作用;用PI法通过流式细胞仪检测细胞周期;RT-PCR方法检测转录因子GATA-1、胞苷脱氨酶(CDA)及脱氧胞苷激酶(DCK)mRNA水平的变化。结果 VPA和SAHA共同联合Ara-c用药组细胞生长抑制率明显高于VPA联合Ara-c组及SAHA联合Ara-c组,各组间相比,具有显著性差异。Dami细胞经过VPA和SAHA处理后均出现细胞周期阻滞现象,主要阻滞在G1期,与对照组相比差异有显著性(P0.05);VPA和SAHA联合用药组G1期细胞所占比例高于SAHA组(P0.05),与VPA组差异无显著性(P0.05)。VPA组、SAHA组、VPA和SAHA联合用药组GATA-1和CDA mRNA表达水平均低于对照组(P0.05),各组间差异无显著性(P0.05);VPA组DCK mRNA表达水平高对照组(P0.05)、SAHA组与对照组比较差异无显著性(P0.05)、VPA和SAHA联合用药组DCK mRNA表达水平高于VPA组和SAHA组(P0.05)。结论 VPA联合SAHA可增强阿糖胞苷对Dami白血病细胞的杀伤作用,可能是通过增加DCK的表达,从而增加阿糖胞苷体内活性代谢产物所致。