Tracing Leukemia Stem Cells and Their Influence on Clinical Course of Adult Acute Myeloid Leukemia

BackgroundAcute myeloid leukemia (AML) evolves from neoplastic transformation of stem cell disease termed “leukemia stem cells” (LSCs). An unsatisfactory response to AML therapy is determined by the presence of minimal residual disease (MRD). The predominance of LSCs might anticipate sustained MRD results. The present study aimed to demonstrate the effect of LSCs on MRD at induction days 14 and 28 on overall survival (OS) and disease-free survival (DFS) and to compare LSC expression with MRD status.Patients and MethodsA total of 84 patients with de novo adult AML underwent testing using LSC panels for CD38/CD123/CD34/CD45 and CD90/CD133/CD45/CD33 and different regular MRD panels.ResultsAt day 14 after induction, the high expression of CD123 and CD133 had adverse effects on both OS and DFS (P = .004 and P ≤ .001 and P ≤ .001 and P ≤ .001, respectively). Greater expression of CD34⁺/CD38⁻/CD123⁺ resulted in unfavorable OS and DFS (P ≤ .001 for both). Both CD34⁺/CD38⁻/CD123⁺ and CD34⁻/CD38⁺/CD123⁺ expression at day 14 after induction had an adverse effect on DFS only (P < .001 and P = .029, respectively). On multivariate analysis, CD133 expression and MRD status were independent prognostic parameters (hazard ratio [HR], 2.3; 95% confidence interval [CI], 1.2-4.4; P = .015; and HR, 2.9; 95% CI, 1.0-7.9; P = .041). At day 28 after induction, MRD and increased CD123⁺/CD34⁻, CD34⁺/CD38⁻/CD123⁺, CD133⁺/CD33⁻ expression were associated with inferior OS (P = .016, P = .0035, P = .0.002, and P = .002, respectively). MRD and high expression of CD34⁺CD123⁺, CD133⁺/CD33⁻, CD34⁺/CD38⁻/CD123⁺ were associated with inferior DFS (P < .001, P = .002, P < .001, P < .001, respectively). On multivariate analysis, only CD133⁺/CD33⁻ expression was the independent prognostic factor (HR, 3.1; 95% CI, 1.5-6.7; P = .003).ConclusionsEstimation of LSC expression is a sensitive indicator of the response to therapy in adult patients with AML and might be a better prognosticator than the findings from regular MRD panels.     

合成成骨生长肽对人骨髓间充质干细胞成骨转化的促进

背景：成骨生长肽在体内外细胞培养中具有明显的促成骨活性,这种促成骨作用的分子机制还不清楚,现已通过人工方法成功制备了合成成骨生长肽。 目的：探讨合成成骨生长肽对体外培养的人骨髓间充质干细胞向成骨方向分化的作用。 设计、时间及地点：基因和蛋白水平的细胞学体外观察,于2006-07/2007-12在福建省医学科学研究所基因工程实验室及复旦大学附属中山医院中心实验室完成。 材料：骨髓标本来源于福建省立医院骨一科收治的男性髂骨植骨患者,合成成骨生长肽由中国科学院上海生命科学研究院生物化学与细胞生物学研究所崔大敷教授惠赠,ERK1/2抑制剂U0126为美国CST公司产品。 方法：密度梯度离心法体外分离培养人骨髓间充质干细胞,单纯矿化液组加入由10 mmol/Lβ-甘油磷酸钠、50 mg/L L-抗坏血酸组成的矿化液;10-7,10-9,10-11 mol/L合成成骨生长肽组分别加入对应浓度的合成成骨生长肽,再加入矿化液;常规培养组加入含体积分数为0.1胎牛血清的低糖DMEM。 主要观察指标：倒置显微镜观察细胞形态变化,RT-PCR法和免疫组织化学染色检测成骨标志物的表达,Western-blot法分析合成成骨生长肽对ERK1/2信号通路的影响,观察U0126对合成成骨生长肽作用的干预。 结果：加入合成成骨生长肽后,骨髓间充质干细胞体积增大,突起增多,呈多角形,胞浆含有较多颗粒状物质,出现致密细胞结节。合成成骨生长肽在mRNA和蛋白水平均能促进成骨标志物碱性磷酸酶、Ⅰ型胶原、骨钙素的表达,定量分析结果显示10-9 mol/L合成成骨生长肽促成骨作用最强。加入合成成骨生长肽后能够引起ERK1/2信号通路的持续性激活,经U0126预处理后几乎完全阻断了合成成骨生长肽对骨髓间充质干细胞的促成骨作用。 结论：合成成骨生长肽可明显促进人骨髓间充质干细胞向成骨方向的转化,在10-9 mol/L浓度下促成骨能力最强,其促成骨作用可能是通过激活MAPK家族ERK1/2途径实现的。     

基因干扰机制及其在细胞信号转导中的应用

基因干扰是一种新兴的基因阻断技术,是外源和内源性双链RNA在细胞内使特异性序列的基因表达受抑。基因干扰技术能高效特异的阻断基因的表达,可以确定复杂的信号传导途径中不同基因的上下游关系,是研究信号转导通路的有力工具。基因干扰技术可有效抑制目的基因表达mRNA以及蛋白质产物,其可以简便、特异、高效、稳定地下调目的基因的表达,亦可在不影响其他物质的情况下,剔除目的基因。基因干扰技术比以前用于基因功能研究和应用的各种方法更优秀,但基因干扰技术对于哺乳动物细胞株的转染效率低;哺乳动物细胞中对双链RNA或小干扰RNA的导入会产生拮抗作用等方面亦有待改进。将有效且具高度安全性的小干扰RNA用于医疗,前景令人期待。     

系统性红斑狼疮患者树突状细胞CD11c^＋，CD123^＋亚群与疾病活动性的关系

目的 探讨系统性红斑狼疮(systemic lupus erythematosus,SLE)患者外周血树突状细胞CD11c+,CD123+亚群与疾病活动性、肾脏损伤及血清抗ds-DNA抗体产生的关系.方法 选定SLE疾病组51例、疾病对照组30例(类风湿关节炎、舍格伦综合征患者各15例)和正常对照组30例,采用流式细胞术检测上述指标.结果 ①SLE患者外周血树突状细胞CD11c+,CD123+亚群比例均显著低于正常对照组(P<0.01),而疾病对照组与正常对照组之间差异无统计学意义(P>0.05).②疾病活动期SLE患者外周血树突状细胞CD123+亚群比例显著高于稳定期患者(P<0.01),而两者CD11c+亚群比例之间差异无统计学意义(P>0.05).③SLE肾病组外周血树突状细胞CD123+亚群比例显著高于非肾病组患者(P<0.01),两者CD11c+亚群比例之间差异无统计学意义(P>0.05);ds-DNA+组SLE患者外周血树突状细胞CD11c+,CD123+亚群比例均显著低于ds-DNA-组(P<0.05).结论 树突状细胞CD11c+,CD123+亚群的变化可能是SLE发病机制中的关键环节之一.     

Comparison of [123I]metaiodobenzylguanidine kinetics with heart rate variability and plasma norepinephrine level

Background  [¹²³I]Metaiodobenzylguanidine (MIBG) imaging has been used to assess cardiac sympathetic nerve abnormalities. We evaluated the clinical significance of myocardial MIBG imaging as a measure of cardiac sympathetic nervous system function by comparing it to heart rate variability and plasma norepinephrine level. Methods and Results  In 211 subjects, we analyzed heart rate variability with 24-hour electrocardiography, performed scintigraphy with MIBG, and measured plasma norepinephrine levels. Time and frequency domain measures of heart rate variability were calculated with the Marquette heart rate variability program (Marquette Electronics, Milwaukee, Wis.). Early and late myocardial MIBG uptakes were measured at 15 and 150 minutes after injection, respectively. MIBG clearance rate from the heart and heart-to-lung and heart-to-mediastinum ratios of MIBG activities were calculated. On the whole, heart rate variability, including low-frequency power, correlated positively, but modestly so, with late MIBG uptake and negatively with MIBG clearance rate. The plasma norepinephrine level correlated negatively with late MIBG uptake and with heart rate variability, including low-frequency power, and positively with MIBG clearance rate. Similar correlations were also observed in patient subgroups with coronary artery disease, diabetes mellitus, and renal failure, but these correlations were weak (R ²<0.5). Conclusions  Increased cardiac sympathetic nervous system activity may be associated with increased myocardial MIBG clearance and decreased heart rate variability, including low-frequency power. Because these associations were not strong, however, the combination of heart rate variability with MIBG may allow an interactive assessment of the cardiac autonomic nervous system.     

BQ123对体外循环缺血再灌注心肌胰岛素抵抗干预作用的实验研究

目的:探讨内皮素受体拮抗剂BQ123对体外循环缺血再灌注心肌胰岛素抵抗(IR)的干预作用。方法:将18条杂种犬分为3组(n=6),Ⅰ组主动脉阻断30min,Ⅱ组主动脉阻断120min,Ⅲ组主动脉阻断120min且心脏停博液中加入BQ123。分别于体外循环转流前、主动脉开放后第15、45、75min4个时点,采集动脉、冠状静脉窦血液标本并进行右房心肌活检,测定各相关指标。结果:与Ⅱ组比较,Ⅲ组的动脉血糖、胰岛素、IR指数、应急激素、血浆内皮素-1及血浆肿瘤坏死因子-α水平升高幅度较小,心肌对葡萄糖的摄取和利用提前至再灌注45min,恢复至正常值更快(P<0.05或P<0.01)。结论:BQ123可以减轻体外循环缺血再灌注过程中的心肌IR,对其引起的损伤具有保护作用。     

~(123)I-间碘苄胍心肌显像对慢性心力衰竭的诊断价值

目的:评价123I-间碘苄胍心肌显像对慢性心力衰竭的诊断价值。方法:共检测对象30例,其中慢性心力衰竭患者15例,正常对照健康志愿者15例。采用123I-MIBG行早期(20 min)及延迟(3 h)平面心肌显像,采用心/上纵隔(H/M)作相对半定量分析。结果:两组早期(H/M)均低于延迟相(P<0.01);心力衰竭组早期与延迟H/M均低于正常对照组(P<0.01),M IBG洗脱率(WR)高于正常对照组(P<0.01)。结论:123I-间碘苄胍显像能发现慢性心力衰竭患者早期肾上腺素能神经功能受损,是评价心力衰竭早期自主神经病变的无创伤性指标。     

Two phase imaging of<Superscript>99m</Superscript>Tc-SESTAMIBI and<Superscript>123</Superscript>I-BMIPP for patients with angina pectoris

We saw three cases of angina pectoris in which 99mTc-SESTAMIBI delayed images at rest were useful in diagnosing ischemia risk areas. These findings indicated that delayed 99mTc-SESTAMIBI images may be more sensitive to slight ischemia than 123I-BMIPP images, and suggested that imaging with 99mTc-SESTAMIBI twice at rest may be more effective. The addition of 123I-BMIPP SPECT was considered to be useful in making an evaluation of the severity of ischemia.