益气养阴方诱导急性白血病细胞凋亡的实验研究

目的：观察益气养阴方诱导急性白血病模型小鼠细胞凋亡的作用。探讨益气养阴方治疗急性白血病的作用机制。方法：以L7212白血病小鼠为研究对象，用益气养阴方浓缩液给小鼠灌胃8d后处死，利用光学显微镜，DNA琼脂糖凝胶电泳等手段观察益气养阴方对急性白血病的作用。结果：形态学观察可见细胞凋亡特征，DNA琼脂糖凝胶电泳图谱显示细胞凋亡现象。结论：本研究提示诱导白血病细胞凋亡是益气养阴方治疗急性白血病的重要机制之一。     

阿克拉霉素诱导原代白血病细胞凋亡的实验研究

目的　研究阿克拉霉素 (ACM)体外抑制原代急性白血病 (AL)细胞的生长及其机理。方法　MTT法研究 37例初发AL细胞的生长抑制。DNA片段原位末端标记 (TUNEL)法检测 2 0例AL细胞的凋亡率。结果　ACM体外能明显抑制原代AL细胞的生长 ;细胞形态学、DNA琼脂糖凝胶电泳均证实ACM能诱导原代AL细胞凋亡 ;与空白对照相比 ,ACM在体外与原代AL细胞共同培养 15小时后 ,TUNEL阳性细胞率明显增高 ,差异有统计学意义 (30 89± 15 90 %对 14 85± 15 90 %;P <0 0 1) ;且TUNEL阳性细胞率与MTT抑制率呈正相关 (r =0 32 6 ,P =0 0 4)。结论　诱导细胞凋亡是ACM抑制原代AL细胞增殖的重要机制之一。     

化疗药物诱导急性白血病原代细胞凋亡的研究

目的：探讨化疗药物诱导急性白血病（AL）原代细胞凋亡的时间,剂量,效应,关系,方法：以成人AL原代细胞为研究,采用高,中、低3种浓度梯度,模拟人体应用HHar,Ara-C和ACR后的最大血液浓度,应用一系列经典方法检测细胞凋亡,并分析得出相应的时间,剂量,效应关系。结果：HHar,Ara-C具有时间－效应及剂量－效应线性趋势,而CR低剂量组诱导细胞凋亡的能力大于高剂量组,并且有时间－效应线趋势;高剂量组HHar,Ara-C诱导细胞凋亡的能力大于高剂量组ACR,而低剂量组ACR诱导细胞凋亡的能力大于低剂量组HHar及Aar-C,3种花物对AML原代细胞诱导凋亡的效果优于对ALL原代细胞,结论：AL原代细胞对细胞凋亡的敏感性也是决定化疗效果的关键因素。     

氧化酚砷诱导急性早幼粒细胞性白血病细胞凋亡的研究

目的：了解氧化酚砷（ｐｈｅｎｙｌａｒｓｉｎｅ ｏｘｉｄｅ,ＰＡＯ）对急性早幼粒细胞性白血病（ＡＰＬ）细胞系ＮＢ４细胞的可能作用。方法：在台盼蓝排除法计数活细胞和细胞活力的基础上,通过细胞形态不和流式细胞仪检测细胞凋亡。通过对细胞进行Ｒｈｏｄａｍｉｎｅ（Ｒｈ）１２３和碘化丙啶双重染色,并应用流式细胞仪检测其荧光强度,以反映细胞线粒体跨膜电位（ΔΨｍ）。结果和结论：低浓度（０．０５和０．０１μｍｏｌ／     

FLT3靶向抑制诱导急性髓细胞白血病细胞凋亡的实验研究

目的通过检测FMS样酪氨酸激酶3（FLT3）靶向抑制对急性髓细胞白血病（AML）细胞株THP-1、HL-60凋亡的作用,探讨FLT3异常表达在AML细胞凋亡中的作用。方法用FLT3靶向短发夹状干扰RNA (FLT3-shRNA)特异性下调THP-1、HL-60细胞中FLT3的表达。用Annexin V-FITC检测早期凋亡细胞比例,用 DNA Ladder检测细胞凋亡的特征条带,用TUNEL细胞原位杂交的方法检测细胞凋亡晚期形态学变化和比例,用流式细胞法（FCM）检测细胞周期的变化。结果用Annexin V-FITC检测FLT3-shRNA处理48 h的THP-1、HL-60细胞的早期凋亡率与对照组相比都有增加（P＜0.01）;两细胞株都检测到了凋亡细胞梯状条带（DNA Ladder）;细胞周期都出现G0/G1期细胞比例的增加（P＜0.01）,S期细胞比例的下降（P＜0.05）。另外在THP-1细胞TUNEL细胞原位杂交也观察到晚期凋亡细胞比例的明显增加（P＜0.01）。结论shRNA介导的FLT3抑制可诱导THP-1、HL-60细胞凋亡,支持FLT3过表达具有抗AML细胞凋亡的作用。     

T细胞急性淋巴细胞白血病对肿瘤坏死因子相关的凋亡诱导配体的敏感度研究

目的观察T细胞急性淋巴细胞白血病（T-ALL）对肿瘤坏死因子（TNF）相关的凋亡诱导配体(TRAIL)所介导的细胞毒的敏感度,并探讨其机制。方法以T-ALL细胞株3株及原代细胞为研究对象,通过测定细胞表面TRAIL受体表达、TRAIL作用后细胞的存活率及凋亡,观察T-ALL对TRAIL的敏感性。结果T-ALL细胞对TRAIL中度至高度耐受,其原因主要是细胞表面凋亡受体表达低下。 结论T-ALL对TRAIL耐受,有可能是T-ALL迅速克隆扩增及GVL效应差的一个重要机制。     

紫草素调节有氧糖酵解代谢诱导急性淋巴细胞白血病细胞凋亡

目的:探讨紫草素通过调节白血病细胞能量代谢影响细胞增殖与凋亡的具体机制。方法:采用MTS法检测细胞增殖,流式细胞术检测细胞凋亡;采用Western blotting 法检测细胞凋亡相关蛋白的表达,包括cleaved-caspase 8、cleaved-PARP、cleaved-caspase 3。利用丙酮酸激酶（PK）活性检测试剂盒评估紫草素对PK酶活性的影响;利用海马能量代谢检测仪检测Reh细胞经紫草素处理后其有氧糖酵解代谢水平的变化。结果:紫草素以时间剂量依赖性的方式抑制白血病细胞增殖,并诱导白血病细胞凋亡,凋亡率与药物剂量呈正相关关系（P＜0.01）。紫草素激活caspase级联反应,凋亡相关蛋白cleaved-caspase 8、cleaved-PARP及cleaved-caspase 3的表达随紫草素的剂量增加而增加。紫草素抑制白血病细胞PK酶的活性,并抑制有氧糖酵解代谢的代偿能力（P＜0.001）。结论:紫草素抑制急性淋巴细胞白血病Reh细胞有氧糖酵解代谢的代偿能力,并诱导Reh细胞以caspase依赖性的方式凋亡。     

细胞毒化疗对急性白血病原位凋亡诱导作用的体内研究

目的：观察细胞毒化疗对急性白血病细胞原位凋亡的影响。方法：应用ＤＮＡ原位末端标记（ＩＳＥＬ）方法,检测初发及经治的３１例急性白血病骨髓塑包切片内细胞原位凋亡数量及特征,以１０例缺铁性贫血为对照,并进行自身组间对照。结果：初始ＡＬ凋亡减少,与对照组相比有显著差异（Ｐ〈０．０１）。化疗有效者凋亡明显增加,凋亡细胞数与原始细胞下降百分数呈正相关（ｒ值０．９１４２）。结论：未经治疗的ＡＬ存在凋亡逃逸现象,细胞毒化疗产生疗效的机制可能是促进细胞凋亡。凋亡检测可能成为判断急性白血病预后的有用指标。     

高三尖杉酯碱诱导急性白血病原代细胞凋亡和杀伤作用的研究

目的　探讨高三尖杉酯碱 (HHar)对AML的疗效明显优于ALL的可能机制。方法　以成人AL原代细胞为研究对象 ,采用高、中、低三种浓度梯度对HHar进行研究。采用光镜、扫描电镜下观察细胞凋亡的形态变化 ,透射电镜下观察细胞超微结构改变 ,DNA凝胶电泳、二苯胺法、流式细胞术等方法 ,证实HHar确可诱导AL原代细胞凋亡。尔后采用光镜计数细胞凋亡率、二苯胺定量测定凋亡细胞的DNA片段化率及台盼蓝染色光镜下计数坏死率三种方法来观察HHar对ALL及AML原代细胞的诱导凋亡和杀伤 ,得出相应的时间、剂量、效应关系 ,并进行对比分析。结果　HHar对AML原代细胞诱导凋亡的敏感性高于ALL原代细胞。结论　Hhar对AML原代细胞诱导凋亡的敏感性高是其临床疗效优于ALL的可能机制     

Morphologic Evidence of Apoptosis in Childhood Acute Myeloblastic Leukemia Treated with High-Dose Methylprednisolone

We have previously demonstrated that various subtypes of AML children respond to high-dose methylprednisolone (HDMP; 20-30 mg/kg/day) which could induce in vivo differentiation of myeloid leukemic cells to mature granulocytes. In this study we have evaluated whether apoptosis occurs in AML cells of patients treated by HDMP using morphological criteria. For light and electronmicro-scopic examination bone marrow aspirates were obtained four days and two weeks after methylprednisolone (30 mg/kg/day) treatment from two children with newly diagnosed AML (AML-M3 and AML-M4). In both patients maturation of leukemic cells has previously been reported four days (in patient with AML-M3) and two weeks (in patient with AML-M4) after HDMP treatment. Electronmicroscopy revealed the characteristic ultrastructural changes of various stages of apoptosis four days after HDMP treatment in a case with AML-M3. Morphologic evidence of apoptosis induced by HDMP were also detected on Wright-stained and toluidine blue stained semithin sections of BM preparations in a patient with AML-M4 and AML-M3 respectively. These findings suggest that HDMP which could induce in vivo terminal differentiation in myeloid leukemic cells is also able to induce apoptosis in patients with AML. The possibility of HDMP-induced apoptosis should be evaluated in a larger series of patients with AML and other types of malignant tumors.     

Targeting Apoptosis Pathways in Acute Myeloid Leukemia

The anti-apoptotic protein BCL2 is overexpressed in hematological malignancies, including acute myeloid leukemia (AML), favoring tumor survival and chemoresistance. BCL2 inhibits BIM and BAX, effector proteins necessary for the formation of pores in the mitochondrial outer membrane, and its inhibition primes cells for the release of cytochrome c and subsequent apoptosis. Such priming can be facilitated by venetoclax, an oral BCL2 inhibitor, therefore representing an ideal strategy to induce

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Lidamycin Induces Apoptosis of B-Cell Lymphoma Cells and Inhibits Xenograft Growth in Nude Mice

OBJECTIVE To study the cytotoxicity of Lidamycin (LDM) and its induction of apoptosis in Raji and Daudi cells of B-cell lymphoma, and the inhibition of growth of the lymphoma Raji xenograft in nude mice.METHODS MTT assay was used to observe the inhibition by LDM on the proliferation of the Raji and Daudi cells. Annexin V-FITC/PI double-stain, in combination with flow cytometry (FCM), was used to determine the induction of apoptosis by LDM in Raji cells. The B-cell lymphoma Raji xenograft model in nude mice was set up to detect the in vivo antitumor activity of LDM.RESULTS LDM markedly inhibited the proliferation of the Raji and Daudi cells in vitro, with IC50 values of 7.13×10-11 mol/L and 2.91×10-10 mol/L, respectively. The apoptotic rates of Raji cells were respectively 77.98% and 67.63% at 0.5 nmol/L and 0.25 nmol/L of LDM, indicating an obvious induction of apoptosis in Raji cells. LDM inhibited the formation and growth of human B-cell lymphoma Raji xenograft in nude mice. The inhibition rates of tumor growth were respectively 74.9% and 65.2% in LDM at dosage group of 0.05 mg/kg and 0.025 mg/kg, suggesting an apparent prolongation of survival time in the nude mouse bearing lymphoma.CONCLUSION LDM can effectively induce apoptosis of the B-cell lymphoma cells and inhibit the xenograft growth in nude mice.     

抗CD44抗体HI44a对白血病细胞分化与凋亡作用的体外研究

背景与目的探讨抗CD44抗体HI44a对新鲜白血病细胞分化及凋亡的作用。材料与方法从细胞形态学、四氮唑蓝(NBT)还原反应和细胞分化特异性抗原CD11b,CD14和CD15的变化,体外研究HI44a对31例急性髓系白血病患者白血病细胞的诱导分化作用。并利用Annexin-Ⅴ试剂盒检测HI44a对白血病细胞的凋亡诱导,RT-PCR方法检测其对细胞分化相关因子G-CSF,M-CSF及原癌基因c-myc表达的影响。结果经HI44a作用后,白血病细胞形态向成熟方向转变;M2~M5各亚型的NBT还原反应阳性率分别升高到31%(对照为9%)、55%(对照为10%)、25%(对照为12%)和32%(对照为11%),与对照组相比,差异均有统计学意义(P<0.01)。CD11b,CD14和CD15表达分别由对照组的9.65%、27.40%、57.38%升高到19.29%、40.60%和66.82%(P均<0.01)。细胞的早期凋亡率由对照组的26.21%升高到41.18%。RT-PCR检测发现HI44a作用后,M-CSF表达增强,而原癌基因c-myc表达降低。结论HI44a能够有效的诱导白血病细胞分化及凋亡,为治疗急性髓性白血病提供了一条新思路。     

抗CD44抗体HI44a诱导THP-1细胞凋亡作用的研究

背景与目的：研究抗CD44抗体HI44a体外诱导白血病细胞THP-1凋亡的作用及其机制。材料与方法：应用Annexin-Ⅴ/PI染色法、原位凋亡检测试剂盒及透射电镜分别检测形态学变化及其凋亡情况,RT-PCR及western-blot方法检测原癌基因c-myc mRNA及蛋白水平的表达,JC-1染色法检测细胞线粒体膜电位的变化,流式细胞仪检测抗凋亡蛋白Bcl-2的表达。结果：采用多种方法均可证实,HI44a对THP-1细胞有明显的诱导凋亡作用。HI44a明显抑制THP-1细胞抗凋亡蛋白Bcl-2的表达（P﹤0.05）;同时c-myc在mRNA及蛋白水平的表达水平均明显降低;并可诱导细胞线粒体膜电位的改变。结论：HI44a能够有效诱导THP-1细胞凋亡。其作用机制可能是与调节相关癌基因及抗凋亡蛋白的表达,降低线粒体膜电位有关。     

体外化疗药物诱导白血病细胞凋亡预测临床疗效

[目的]探讨急性髓系白血病(AML)患者体外化疗药物诱导白血病细胞凋亡在化疗疗效预测中的价值。[方法]应用TdT介导的脱氧核苷酸切口和末端标记法(Tunel)、单克隆抗体免疫组化检测等方法研究42例初治AML患者体外化疗药物诱导白血病细胞凋亡、bcl鄄2表达与临床化疗疗效的关系。[结果]42例AML患者中,30例获完全缓解(CR)者,bcl鄄2表达显著低于12例未缓解(NR)者(P<0.05);CR患者柔红霉素(DNR)和阿糖胞苷(Ara鄄C)体外诱导白血病细胞凋亡率均分别高于NR患者,差异有显著性(P均<0.05);体外DNR和Ara鄄C两药诱导白血病细胞的总凋亡率,可以作为临床预测AML患者DA方案疗效的定量指标。[结论]体外化疗药物能否有效地诱导白血病细胞凋亡是判断AML患者化疗敏感性的重要指标。     

Interaction of Acute Leukemia Cells with the Bone Marrow Microenvironment: Implications for Control of Minimal Residual Disease

There is increasing evidence for an interaction between acute leukemia cells and the microenvironment of the bone marrow. Blast cells from cases of acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) bind to cellular and extracellular matrix components of the bone marrow stroma. In AML, adhesion to stroma is mediated by the combined action of β (principally VLA-4) and β2 integrins, while in precursor-B ALL VLA-4 and VLA-5 integrins play a major role. Adhesion molecules such as CD31, CD44, non-β1, β2 integrins, growth factor receptors such as c-kit, and other molecules are also likely to play a role. Binding of acute leukemia blasts to ligands on stroma has several pathophysiological consequences. Stromal contact is able to inhibit programmed cell death (apoptosis) in a proportion of cases of both AML and ALL. In ALL, diffusible molecules derived from stroma appear to contribute. Marrow stroma also plays a part in regulating leukemic cell proliferation. While this is partly due to stromal production of hemopoictic growth factors, in soluble or transmembrane form or bound to extracellular matrix, signalling mediated directly by binding of adhesion molecules on teukemic cells may also have a role. Contact of ALL blasts with marrow fibrobtasts is followed by migration of leukemic cells, utilizing VLA-4 and VLA-5 integrins, potentially allowing homing of blasts to favourable microenvironmental sites, or controlling egress into the circulation. AML cells compete for stromal binding sites with natural killer cells and cytotoxic lymphocytes, which are known to inhibit their clonogenic growth. We speculate that these complex interactions between leukemic blasts, cellular and matrix components of stroma, and cytotoxic lymphocytes, play a critical role in determining the fate of small numbers of leukemic cells surviving after cytotoxic chemotherapy.     

Prognostic Factors in Acute Promyelocytic Leukemia: A Retrospective Study of 67 Cases

In a cohort of 67 adult patients with newly diagnosed untreated acute promyelocytic leukemia (APL), the initial clinical and biological parameters were submitted to multivariate analysis for potential prognostic significance. Median age of the patients was 40 years and the hematologic characteristics of the patients were those regularly seen. Complete remission (CR) was achieved in 43 cases (64%). Fourteen patients died within 4 weeks of diagnosis, due to severe hemorrhage. Factors predictive of hemorrhagic death in the multivariate analysis were hyperuricemia (p = 0.001), splenomegaly (p = 0.009), anemia (p = 0.02), high serum levels of LDH (p = 0.02), increased prothrombin time (p = 0.04), and hypercreatininemia (p = 0.05). Pretreatment patient characteristics for poor prognosis and achieving CR were hyperuricemia (p = 0.0002), splenomegaly (p = 0.01), anemia (p = 0.02), and lymphadenopathy (p = 0.04). The median disease-free survival (DFS) was 15.6 months. Poor prognostic factors for DFS were hyperuricemia (p = 0.007), and splenomegaly (p = 0.03). Maintenance chemotherapy had no statistically significant impact on CR duration. Median survival duration was 10 months. Poor prognostic factors for survival were hyperuricemia (p = 0.0005), and elevated serum LDH levels (p = 0.01).