磁珠分选U251细胞系中的CD133+细胞及其生物学特性

背景：脑肿瘤干细胞理论认为,脑肿瘤干细胞是脑肿瘤细胞中“种子”细胞,是脑肿瘤发生、浸润和复发的关键细胞。 目的：观察人多形性胶质母细胞瘤U251细胞系中CD133⁺细胞的增殖、分化及体内致瘤性等生物学特性。 方法：运用磁珠分选技术分选U251细胞系中的CD133⁺和CD133^-细胞亚群;MTT法绘制两个亚群细胞的生长曲线;单克隆形成率实验检测2个亚群细胞的增殖能力;免疫荧光检测CD133⁺细胞亚群的多向分化能力;裸鼠移植实验检测2个亚群细胞在裸鼠体内致瘤性的差异。 结果与结论：U251细胞系中只有约4.5%的CD133⁺细胞;分选后的CD133⁺细胞能增殖形成典型的脑肿瘤干细胞球,生长曲线显示CD133⁺细胞增殖能力明显强于CD133^-细胞;单克隆形成率实验显示CD133⁺细胞能形成脑肿瘤干细胞球的细胞比率达到78.5%~92.4%,而CD133^-细胞仅有0.8%~2.4%;CD133⁺细胞能分化为具有GFAP和NeuN成熟表型的肿瘤细胞;CD133⁺的致瘤率为71.42%,而CD133^-细胞无致瘤性。提示U251细胞系中存在少量具有增殖、多向分化与体内致瘤能力的CD133⁺细胞,CD133⁺细胞是符合肿瘤干细胞定义的细胞亚群。     

CD133+卵巢癌干细胞样细胞在血管内皮细胞中的分化

背景：大量研究证实,新生血管形成在肿瘤的生长、浸润以及转移过程中发挥重要作用。 目的：探讨CD133+卵巢癌干细胞样细胞向血管内皮细胞分化的特点。 方法：通过无血清培养方法从卵巢癌A2780细胞株中成功诱导出CD133⁺卵巢癌干细胞样细胞,在体外接种于铺或不铺Matrigel基质胶的96孔板内,观察不同时间点CD133⁺卵巢癌干细胞样细胞和人脐静脉内皮细胞形成管腔样结构能力。通过裸鼠皮下移植实验,免疫荧光法观察CD133⁺卵巢癌干细胞样细胞在卵巢癌血管新生中的作用。 结果与结论：CD133⁺卵巢癌干细胞样细胞和人脐静脉内皮细胞(阳性对照)在未铺 Matrigel基质胶上并不能形成相应的管腔结构,且不表达内皮细胞标志物CD31,在Matrigel基质胶上能够形成相对稳定的管腔结构,CD31表达明显。CD133⁺卵巢癌干细胞样细胞接种裸鼠皮下成瘤后,可观察到肿瘤组织中有人源性CD31的表达。结果表明CD133⁺卵巢癌干细胞样细胞能够分化为血管内皮细胞,参与肿瘤血管重建。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

β-catenin基因沉默对肝癌干细胞干性转录因子的影响

背景：肝癌干细胞是导致癌细胞形成、更新和增殖的原因,寻找针对肝癌干细胞治疗的关键靶点,并进一步拓展肝癌综合治疗手段是重要研究课题。目的：观察β-catenin基因沉默后CD133⁺Hep G2细胞干性转录因子变化,探讨β-catenin调控肝癌干细胞干性的作用机制。方法：采用免疫磁珠筛选CD133⁺Hep G2细胞,然后经干细胞培养基诱导、扩增方案获得CD133⁺Hep G2肝癌干细胞,流式细胞术鉴定CD133⁺Hep G2细胞阳性率,RNA干扰技术构建沉默β-catenin基因表达的β-catenin-sh RNA慢病毒质粒,转染CD133⁺Hep G2肝癌干细胞72 h,荧光标记并评估转染效率。确认β-catenin沉默后,平板克隆形成实验观察CD133⁺Hep G2肝癌干细胞增殖情况,流式细胞术检测CD133⁺Hep G2肝癌干细胞的细胞周期,q RT-PCR和Western blot检测干性转录因子SOX2,NANOG,OCT...     

人骨骼肌源性血管外膜细胞对人脐血CD34+细胞的体外造血支持作用#br#

文题释义： 血管外膜细胞：是血管周围星状细胞,分布于全身的毛细血管和微血管的管壁,是血管周围微环境的重要核心组成成分。它们表达CD146、NG2、PDGFRβ、LepR、Nestin等标记物,而不表达内皮细胞标记物CD144、vWF、CD31及造血细胞标记物CD34、CD45、CD14。研究显示血管外膜细胞是间充质干细胞的前体细胞,其表达间充质干细胞表面标记物,具有多向分化潜能,并可支持造血。 造血干细胞微环境：是造血组织中造血干细胞赖以生存并进行自我更新、多向分化的场所。它由骨内膜微环境和血管微环境组成,前者维持造血干细胞的静止及自我更新,后者促进造血干细胞动员、增殖、分化。 背景：研究显示血管外膜细胞是间充质干细胞的前体细胞,其通过细胞接触或旁分泌效应调节造血干细胞的行为并支持造血,人骨骼肌源性血管外膜细胞对造血的支持作用有待于研究。 目的：从人骨骼肌中分离培养血管外膜细胞并进行生物学特性鉴定,研究其对脐血CD34⁺细胞的体外支持作用。 方法：①利用多参数流式细胞术从人骨骼肌中分选表型为CD146⁺CD56^-CD34^-CD144^-CD45^-的血管外膜细胞,并对其进行生物学鉴定;②建立以CD146⁺人骨骼肌源性血管外膜细胞为滋养层的脐血CD34⁺细胞体外培养体系(实验组),以人骨髓间充质干细胞为滋养层的脐血CD34⁺细胞体外培养体系为阳性对照组,共培养1,2,4周检测培养体系的细胞数量、集落形成能力及免疫表型并进行统计分析。 结果与结论：①通过多参数流式细胞术分选出CD146⁺人骨骼肌源性血管外膜细胞,回测纯度为(91.5±1.85)% (n=5);其表达间充质干细胞表面抗原CD73、CD90、CD105、CD44,不表达造血细胞及内皮细胞表面抗原CD45、CD34、CD31;经诱导培养可向骨细胞、软骨细胞、脂肪细胞及肌细胞分化;②实验组与阳性对照组相比,在细胞数、集落形成能力及免疫表型方面(CD45⁺、CD34⁺CD33^-、CD14⁺、CD10⁺/CD19)差异均无显著性意义(P > 0.05,n=6);无滋养层的空白对照组培养1周时细胞数量明显减少,2周时几乎无细胞存活;③结果表明,CD146⁺人骨骼肌源性血管外膜细胞与人骨髓间充质干细胞一样对脐血CD34⁺细胞具有体外支持作用。 ORCID: 0000-0002-6768-5273(郑波) 中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程     

酸性成纤维细胞生长因子与胚胎干细胞的造血分化

背景：有研究表明,在卵黄囊造血、胎肝造血和胚胎干细胞向造血干细胞分化过程中,酸性成纤维细胞生长因子可强烈表达。 目的：探讨酸性成纤维细胞生长因子对小鼠胚胎干细胞造血分化的作用,在拟胚体培养阶段施加酸性成纤维细胞生长因子,验证酸性成纤维细胞生长因子对造血形成细胞产生的调控作用。 方法：培养小鼠胚胎干细胞,将饲养层上生长状态良好的小鼠胚胎干细胞用胰酶消化成单个细胞后,利用悬滴法制备拟胚体,拟胚体继续悬浮培养,以1,2和5 μg/L酸性成纤维细胞生长因子分别培养3,5,7,9 d,通过免疫荧光法检测胚胎干细胞与拟胚体中酸性成纤维细胞生长因子的表达,流式细胞术检测Flk-1⁺与CD133⁺阳性细胞率。 结果与结论：酸性成纤维细胞生长因子在拟胚体中呈阳性表达。在5 μg/L酸性成纤维细胞生长因子作用下,Flk-1⁺细胞随时间增加表达增加,CD133⁺细胞表达模式与Flk-1⁺细胞类似。在1 μg/L时,Flk-1⁺细胞在7 d时表达达到高峰,随后下降。CD133⁺细胞表达结果类似。而在2 μg/L时,5 d时Flk-1⁺细胞表达升高,随后下降,在9 d时表达又增高。而CD133⁺细胞则总体呈现升高趋势。酸性成纤维细胞生长因子可促进Flk-1⁺与CD133⁺细胞的产生,证明酸性成纤维细胞生长因子能够有效促进拟胚体的扩增以及成血管血液干细胞的产生与增殖。     

骨髓基质细胞联合细胞因子对脐血单个核细胞表面抗原表达的影响

背景：课题组已建立胎儿骨髓基质细胞联合细胞因子的造血细胞体外培养体系,该培养体系能否有效扩增各个发育阶段的造血细胞有待验证。 目的：观察骨髓基质细胞联合细胞因子培养体系对脐血单个核细胞表面抗原CD133、CD34表达的影响。 方法：将从脐血标本中分离出来的单个核细胞接种于无血清培养体系,实验分为3组：①F组：干细胞因子+Flt3配体+促血小板生成素+单个核细胞。②S组：基质细胞+单个核细胞。③SF组：基质细胞+干细胞因子+Flt3配体+促血小板生成素+单个核细胞。在第0,6,10,14天检测有核细胞总数、CD133⁺、CD34⁺、CD133⁺CD34⁺细胞数以及集落形成单位数。 结果与结论：SF组有核细胞总数在各个检测时间点均比其他两组高;除了第14天外,第6、10天两个时间点SF组中CD133⁺、CD34⁺、CD133⁺CD34⁺细胞及集落形成单位数均高于其他组;含骨髓基质细胞的S组和SF组中CD133⁺细胞/有核细胞、CD34⁺细胞/有核细胞、CD133⁺CD34⁺细胞/有核细胞的比例保持在较高的水平。结果说明骨髓基质细胞联合细胞因子能有效的扩增脐血单个核细胞及其中的CD133⁺、CD34⁺、CD133⁺CD34⁺细胞,基质细胞对维持造血干细胞的原始性具有重要的作用。     

肝癌干细胞分离及其细胞生物学特性

背景：正常干细胞和肿瘤干细胞在基因表达和依赖的细胞信号通路上应该存在不同,如何发现能选择性杀伤肿瘤干细胞的治疗手段是一个仍然需要大量研究的课题。 目的：分离人肝癌细胞系肿瘤干细胞MHCC97,分析其细胞生物学特性。 方法：采用流式细胞技术在人高转移肝癌细胞系MHCC97中筛选肿瘤干细胞,分离正常人肝脏干细胞CD133^-CD34^- MHCC97和人肝癌细胞系肿瘤干细胞CD133⁺CD34⁺ MHCC97,分别检测其表型、生长曲线、细胞周期和多系分化能力。 结果与结论：人肝癌细胞系CD133⁺CD34⁺ MHCC97肿瘤干细胞的表型为CD133⁺CD34⁺ ,人肝癌细胞系CD133⁺CD34⁺ MHCC97具有与CD133^-CD34^- MHCC97相似的细胞曲线和生长周期,可以向上皮和内皮细胞分化,并表达相应特异性的分子标志。提示人肝癌细胞系中CD133⁺CD34⁺MHCC97细胞具有肿瘤干细胞的特性,可以向内皮和上皮细胞分化,同时具有肿瘤干细胞的生物学特性,是肿瘤复发转移的根源,也是临床治疗的靶点。中国组织工程研究杂志出版内容重点：干细胞;骨髓干细胞;造血干细胞;脂肪干细胞;肿瘤干细胞;胚胎干细胞;脐带脐血干细胞;干细胞诱导;干细胞分化;组织工程全文链接：     

干细胞相关因子在大肠癌组织及SW620细胞株的表达

背景：肿瘤细胞有多种干细胞标记的表达,深入研究其表达规律有助于揭示肿瘤发病机制、完善肿瘤干细胞理论。 目的：检测大肠癌实体组织中干细胞相关分子标记CD133、CD166、Oct4、Sox2、C-myc、Klf4、Bmi-1与癌旁组织的表达差异,以及CD133免疫磁珠分选阳性与阴性SW620细胞中上述基因的表达差异。 方法：选临床病理诊断清楚的29例大肠癌组织标本提取RNA,RT-PCR检测CD133、CD166、Oct4、Sox2、C-myc、Klf4、Bmi-1在大肠癌组织与癌旁对照组织中的表达。CD133免疫磁珠分选SW620,提取CD133细胞与CD133阴性细胞RNA,RT-PCR检测分选后上述基因的表达差异。 结果与结论：29例标本均诊断为低、中分化腺癌或黏液腺癌,干细胞相关分子标记癌组织与癌旁组织表达灰度相对值癌组织表达均高于癌旁组织(P < 0.05)。RT-PCR检测分选后CD133⁺细胞CD133,CD166,Oct4,Sox2,C-myc,Klf4,Bmi-1表达,结果均高于CD133^-细胞。提示,CD133、CD166、Oct4、Sox2、C-myc、Klf4、Bmi-1相关干细胞标记可作为大肠癌肿瘤干细胞标记并有望用于诊断检测。     

胶质瘤细胞及其干细胞的放疗敏感性差异

目的探讨脑胶质瘤细胞与脑肿瘤干细胞(BTSCs)的放射敏感性差异。方法胶质瘤细胞接种于含10%胎牛血清的DMEM/F12培养基进行培养。用血清剥夺法(无血清的DMEM/F12培养基添加bFGF、EGF和B27,即干细胞培养液)培养胶质瘤干细胞。CD133免疫细胞化学染色鉴定BTSCs。用直线加速器分别以0、2、4、6、8、10Gy X线照射胶质瘤细胞及BTSCs,然后继续培养36h。流式细胞仪检测上述细胞中CD133+细胞比率。采用MTT法检测细胞的存活情况。结果胶质瘤细胞中存在BTSCs,后者能在干细胞培养液中存活并悬浮生长,增殖形成克隆球,具有自我更新和增殖能力,表达特异性标志物CD133。胶质瘤细胞及BTSCs在X线照射后,其增殖能力都下降,但BTSCs的下降幅度远没有胶质瘤细胞大(P0.05)。CD133+比率显示,X射线对普通胶质瘤细胞中极其微量的CD133+细胞几乎没有影响,而BTSCs中的CD133+细胞的比例在0-10GyX射线放射过程中,与放射剂量成正比(P0.05)。结论 BTSCs的放射敏感性明显低于胶质瘤细胞,其机制可能与放疗过程中CD133+细胞的增加有关。     

海洋单细胞海藻体外对人脑胶质瘤干细胞生物学活性的影响

背景：海藻具有广阔的药理活性前景,加强其研究对有目的进行应用开发有重要的指导意义。 目的：观察海洋单细胞海藻在体外对人脑胶质瘤干细胞生物学活性的影响。 方法：以酶消化法培养人脑胶质瘤干细胞,流式细胞分选出CD133阳性细胞,细胞传代获得第3代细胞。流式细胞仪检测海洋单细胞海藻作用前后细胞CD133表达变化,免疫组织化学检测贴壁细胞巢蛋白及胶质纤维酸性蛋白的表达。实验组分别加入不同质量浓度的海洋单细胞海藻,阴性对照加不含药的PBS,将稀释成4,6,8,10 g/L的海洋单细胞海藻加入细胞培养液中并作用24,48,72 h,流式细胞仪检测胶质瘤干细胞生长周期,应用酶标仪检测细胞生长抑制情况。 结果与结论：随着浓度和时间的增加,与对照组相比倒置显微镜下可见实验组胶质瘤干细胞不易聚团成球,出现贴壁分化,并逐渐明显;加药后胶质瘤干细胞CD133表达量明显减少;出现的贴壁细胞免疫组织化学染色巢蛋白及胶质纤维酸性蛋白表达阳性;流式细胞仪检测显示,停滞在S、G2/M期细胞数增加,而G0/G1期细胞数减少;随着浓度和时间的增加,胶质瘤干细胞增殖明显抑制,与对照组相比差异有显著性意义(P < 0.05~0.01)。提示海洋单细胞海藻能够抑制人脑胶质瘤干细胞的增殖,并促进其分化,且作用具有浓度和时间依赖性。     

miR-1231对结肠癌干细胞增殖、凋亡和侵袭的影响

BACKGROUND:Previous studies have found that miR-1231 is down-regulated in colon cancer stem cells (CCSCs), but the effect of miR-1231 on CCSCs remains unclear. OBJECTIVE:To explore the effect of miR-1231 on the proliferation, apoptosis and invasion of CCSCs (CD133⁺CD44⁺). METHODS: CD133⁺CD44⁺ cells and CD133^-CD44^- cells were separated from SW1116 cells by immunomagnetic bead separation. The expression level of miR-1231 in CD133⁺CD44⁺ and CD133^-CD44^- cells was detected by qRT-PCR. miR-1231-overexpressing CD133⁺CD44⁺ cells were transfected with miR-1231 mimics or miR-control by lipofection transfection. The effects of miR-1231 on CD133⁺CD44⁺ cell proliferation, apoptosis and invasion were investigated by MTT, flow cytometry and Transwell assays, respectively. In addition, the expression levels of Ki67, Bax, Bcl-2, MMP-2 and MMP-9 protein in miR-1231-overexpressing CD133+CD44+ cells and control cells were detected by western blot. RESULTS AND CONCLUSION:CD133⁺CD44⁺ and CD133^-CD44^- cells were obtained by the immunomagnetic bead separation. The expression level of miR-1231 in CD133⁺CD44⁺ cells was significantly lower than that in CD133^-CD44^- cells. miR-1231 suppressed CD133⁺CD44⁺ cell proliferation and invasion, but promoted the apoptosis in these cells. Western blot analysis showed that miR-1231-overexpressing CD133⁺CD44⁺ cells had obvious decreases in Ki67, Bcl-2, MMP-2 and MMP-9 protein expression and a significant increase in Bax protein expression compared with control cells. All these results further confirm that miR-1231 inhibits the proliferation and invasion but promotes the apoptosis in CD133⁺CD44⁺ cells. These findings suggest that miR-1231 can be a suppressor of CCSCs, which offers a novel potential therapeutic target for CCSCs and colon cancer.     

miR-34a通过Notch1信号通路对肺癌干细胞的抑制

BACKGROUND:It has been proved that miR-34a plays an inhibitory role in the growth of lung cancer stem cells, but the underlying mechanism remains unclear. OBJECTIVE:To explore the inhibitory effect of miR-34a on lung cancer stem cells and the underlying mechanism. METHODS:The CD133⁺ lung cancer stem cells were separated from lung cancer A549 cell lines using magnetic activated cell sorting method. And miR-34a-overexpressing CD133⁺ lung cancer stem cells were established by liposome transfection technology. Besides, the targeted relationship between miR-34a and Notch1 was analyzed by the dual-luciferase reporter. Afterwards, Notch1 silencing was performed by gene knockout, and its effect on lung cancer stem cells was determined. RESULTS AND CONCLUSION:After sorted and detected by immunomagetic selection and flow cytometry assay respectively, a high rate of CD133⁺ lung cancer stem cell was obtained. And qRT-PCR detected that the expression level of miR-34a in CD133⁺ lung cancer stem cells was significantly lower than that in CD133^- lung cancer stem cells. Moreover, miR-34a-overexpressing CD133⁺ lung cancer stem cells were successfully constructed and miR-34a significantly inhibited proliferation and induced apoptosis of lung cancer stem cells. Dual-luciferase reporter assay indicated that Notch1 mRNA was a target of miR-34a. In addition, Notch1 silencing obviously inhibited proliferation and induced apoptosis of lung cancer stem cells. These findings suggest that miR-34a can inhibite lung cancer stem cells via the Notch1 signaling pathway.     

欧前胡素通过下调c-met的表达提高肺癌CD133~+细胞亚群对吉非替尼的敏感性

目的:研究PC9 CD133~+细胞亚群对吉非替尼的耐药性并探讨欧前胡素提高吉非替尼抗肺癌活性的机制。方法:MTT法检测PC9细胞在吉非替尼和欧前胡素处理下的细胞活力。Western blot实验检测吉非替尼和欧前胡素对PC9细胞c-met表达水平、caspases活化水平及表皮生长因子受体(EGFR)、PI3K、AKT磷酸化水平的影响。流式细胞术检测欧前胡素和吉非替尼对PC9细胞系的CD133~+细胞亚群种群比例的影响及PC9细胞在二者处理下的凋亡率。结果:PC9 CD133~+细胞亚群对吉非替尼的敏感性显著低于PC9 CD133~-细胞亚群。吉非替尼能显著抑制PC9 CD133~-细胞亚群EGFR/PI3K/AKT的活化,但对PC9 CD133~+细胞亚群该通路的影响不大。吉非替尼单独处理能提高PC9细胞系中CD133~+细胞亚群的比例,然而联用欧前胡素后PC9 CD133~+细胞亚群的种群比例显著下降。Western blot实验表明欧前胡素能显著降低PC9 CD133~+细胞亚群的c-met蛋白表达水平表明c-met是欧前胡素的治疗靶点。MTT、Western blot、流式细胞术实验结果表明在PC9 CD133~+细胞亚群中,欧前胡素通过抑制c-met的表达提高吉非替尼对PI3K/AKT的抑制作用,从而诱导PC9 CD133~+细胞亚群发生caspases活化和凋亡。结论:欧前胡素通过下调c-met的表达提高肺癌CD133~+细胞亚群对吉非替尼的敏感性,两者存在协同抗肿瘤效应。     

人脐血单个核细胞中CD133+细胞移植治疗心力衰竭的评价

BACKGROUND:Cell purification can eliminate the biological variability of cells, providing new insight into cell regeneration therapy. OBJECTIVE:To study the Influence of CD133⁺ cells on human umbilical cord blood mononuclear cell transplantation for treatment of heart failure. METHODS:Human cord blood mononuclear cells were isolated using lymphocyte separation medium method, and CD133⁺ and CD133^- cells were sorted using immunomagnetic beads at a cell density of 1×10⁸/L. Forty Sprague-Dawley rats were randomized into five groups: sham group, model group, CD133⁺ cell group, CD133^- cell group and mononuclear cell group. Animal models of heart failure were made using intraperitoneal injection of isoproterenol in all the groups except for the sham group. Rats in the CD133⁺ cell group and CD133^- cell group were given 1 mL CD133⁺ cells plus 1 mL PBS and 1 mL CD133^- cells plus 1 mL PBS via the tail vein, respectively. Rats in the mononuclear cell group were given 1 mL CD133⁺ cells plus 1 mL CD133^- cells via the tail vein, and those in the sham and model groups given 2 mL PBS via the tail vein. After 4 weeks, cardiac pathology, degree of myocardial fibrosis and colonization of CD133⁺ cells in myocardial tissues were observed. RESULTS AND CONCLUSION:Hematoxylin-eosin staining showed that myocardial tissues arranged disorderly in the model group, but regularly in the sham group; myocardial disorders were mildest in the CD133⁺ cell group, successively followed by the mononuclear cell group, and severest in the CD133^- cell group and model group. Masson staining showed that in the model group, collagen fibers were proliferated, arranged irregularly and even broken, while in the sham group, the collagen fibers were less in number and arranged in order. Additionally, there was less reduction in collagen fibers and milder myocardial disorders in the CD133⁺ cell group compared with the other groups. Area of collagen fibers was increased significantly in all the groups except for the sham group (P < 0.05), but this increment was the minimal in the CD133⁺ cell group. Findings from immunohistochemistry and immunofluorescence staining showed that there were no CD133⁺ cells in the myocardial tissues of rats. Therefore, our data indicate that compared with the mononuclear cell transplantation, CD133⁺ cell transplantation exerts superiorities in relieving myocardial damage and reducing myocardial fibrosis. However, CD133⁺ cells are not colonized in the myocardial tissue after transplantation.     

miR-125b通过下调HAX-1的表达提高CD133~+ SW480细胞对顺铂的敏感性

目的:探讨miR-125b在CD133~+结直肠癌细胞中发挥的作用并研究其是否和顺铂的体外治疗有关。方法:用RT-qPCR方法检测miR-125b在常规SW480肿瘤细胞及CD133~+ SW480肿瘤细胞中的表达水平。流式细胞术检测miR-125b和顺铂对SW480细胞系中CD133~+ 细胞比例的影响。MTT法检测miR-125b对顺铂杀伤CD133~+ SW480细胞能力的影响。利用生物信息学及Western blot方法验证miR-125b是否调节CD133~+ SW480细胞中HAX-1的表达。运用JC-1染色、Annexin V染色及Western blot方法研究miR-125b影响顺铂疗效的信号通路的效应。结果:CD133~+ SW480细胞中的miR-125b表达水平显著低于正常结直肠上皮细胞系FHC和常规SW480肿瘤细胞。顺铂体外单独治疗能提高SW480细胞系中CD133~+细胞的比例,然而联用miR-125b模拟物后CD133~+ SW480细胞的比例显著下降。MTT实验结果表明miR-125b可显著增强顺铂对CD133~+ SW480细胞的杀伤活性。Western blot实验表明miR-125b的靶基因可能为HAX-1。miR-125b联合顺铂可引起CD133~+ SW480细胞线粒体膜电位的丧失并诱导线粒体内细胞色素C的释放,进而引起细胞凋亡。转染HAX-1表达载体后miR-125b联合顺铂对CD133~+ SW480细胞的凋亡诱导效应显著降低。结论:miR-125b通过下调HAX-1的表达提高CD133~+结直肠癌细胞对顺铂的敏感性。     

白藜芦醇通过促进Apaf-1/caspase-9复合物的形成增强5-氟尿嘧啶对骨肉瘤CD133~+细胞亚群凋亡的诱导

目的:探讨白藜芦醇联合化疗药物5-氟尿嘧啶对骨肉瘤CD133~+细胞亚群的协同杀伤效应及机制。方法:将人骨肉瘤细胞系MG-63 CD133~+细胞亚群及相应CD133~-细胞亚群用5-氟尿嘧啶及白藜芦醇进行体外处理。MG-63细胞的相对细胞活力用MTT法进行检测;细胞凋亡率用流式细胞术进行检测;用Western blot实验检测caspase-9和caspase-3的活化、Apaf-1的表达水平及细胞色素C的释放;用免疫共沉淀法检测Apaf-1与caspase-9前体的相互作用。结果:5-氟尿嘧啶对MG-63 CD133~+细胞亚群的杀伤活性和凋亡诱导活性均显著低于MG-63 CD133~-细胞亚群。但联用白藜芦醇能显著提高5-氟尿嘧啶对MG-63 CD133~+细胞亚群的细胞活力抑制率。白藜芦醇处理能显著上调MG-63 CD133~+细胞亚群中Apaf-1的表达水平,在MG-63 CD133~+细胞亚群中转染Apaf-1siRNA后,5-氟尿嘧啶联用白藜芦醇的协同效应受到显著抑制。另外,免疫共沉淀实验结果表明白藜芦醇联合5-氟尿嘧啶能显著诱导MG-63 CD133~+细胞亚群中Apaf-1/caspase-9复合物的形成,从而诱导caspase-9发生活化。结论:白藜芦醇通过促进Apaf-1/caspase-9复合物的形成,增强5-氟尿嘧啶对骨肉瘤CD133~+细胞亚群凋亡的诱导。     

恶性肿瘤干细胞标记物CD34在鼻咽癌细胞系的表达

BACKGROUND:Previous research have confirmed that CD34 is closely related to oncogenesis, progress, recurrence, metastasis and drug-resistance of various cancers, but its role in nasopharyngeal carcinoma remains unclear. OBJECTIVE:To sort cells positive and negative for CD34 in nasopharyngeal carcinoma cell lines and to detect cell proliferation and migration. METHODS:Expressions of CD34 in nasopharyngeal carcinoma cell lines 5-8F, 6-10B, CNE1 and CNE2 were detected by flow cytometry. And CD34+ and CD34^- cells were sorted based on cell surface markers for purity identification. Afterwards, proliferation and migration of CD34⁺ and CD34^- cells were detected by MTT assay, colony-formation assay and scratch assay. RESULTS AND CONCLUSION:All four nasopharyngeal carcinoma cell lines expressed CD34 in 0.1%-0.2%, and the level of CD34 was closely related to the cell growth density. The purity of CD34⁺ cell was more than 98% in the sorted CD34⁺ cell populations, but no CD34⁺ cells were found in the sorted CD34^- cell populations. At 1, 3, 5 and 7 days the proliferation rate of CD34⁺ cell, populations was significantly higher than that of CD34^- cells (P < 0.05). Consistently, the colony-formation efficiency of CD34⁺ cell was significantly higher than that of CD34^- cells (P < 0.05). Moreover, CD34⁺ cells migrated significantly faster than CD34^- cells by scratch assay (P < 0.05). In conclusion, CD34⁺ cells cultured in vitro display higher proliferation and migration capacities, indicating that CD34⁺ cells have the potential of nasopharyngeal carcinoma stem cells.