CD34+/CD38- Stem Cell Burden Could Predict Chronic Myeloid Leukemia Patients’ Outcome

Background: The current predictor of the Chronic myeloid leukemia (CML)  patients’ outcome is the degree of response to targeted therapy; here we search for a biomarker predicting CML outcome before start of therapy. This study aimed to assess the impact of the  CD34+/CD38- stem cells (SCs) burden in chronic myeloid leukemia (CML) on  treatment response and patients’ outcomes. Methods: Our study included 65 CML patients in the chronic phase. The patients’  CD34+/CD38- stem cells were quantified  using flowcytometry before and after treatment by frontline imatinib (IM) therapy. The median follow-up for all patients was 18 months. Results: CD34+/CD38- stem cells frequency at diagnosis and after therapies are correlated to known prognostic markers (blast cells count, spleen size, total White cell count, and clinical scores). After therapy, the leukemic stem cells count dropped rapidly. The pretreatment CD34+/CD38- stem cells burden predicts response to frontline therapy. In addition, high SCs frequency at diagnosis predicts poor molecular response, transformation to AML, and poor patients’ outcomes. Conclusion: The percentage of CD34+/CD38- SCs burden at diagnosis reflects the CML disease behavior and is considered a biomarker for predicting CML patients’ response to first-line Tyrosine kinase inhibitors (TKI) therapy.     

rhTPO对CD_(34)~+细胞增殖及形成CFU-MK作用的研究

目的研究重组人TPO（rhTPO）单独及与rhIL-3、rhIL－6、rhSCF协同体外对巨核系的增殖效应。方法采用纯化的CD+34细胞，进行求固体巨核细胞集落培养和液体悬浮培养，研究TPO及与IL－3、IL－6、SCF协同体外对CD+34细胞增殖及向巨核系空向分化的特性，和形成CFU－MK的作用。结果rhTPO可以诱导CD+34细胞形成CFU－MK，增加巨核细胞集落数，这种作用可以被rhIL－3、rhIL－6、rhSCF增强。液体培养中，rhTPO促进CD+34变细胞分化／成熟为表达GPⅡb／Ⅱa的细胞，增加体系中CD+34。细胞，rhIL-3、rhIL－6、rhSCF可以协同TPO的作用。结论TPO作为一种促增殖因子，促进巨核系祖细胞的增殖及分化。     

血小板因子4对巨核细胞的保护作用及其在肿瘤化疗中的意义

目的：研究血小板因子４对造血细胞的艇及其机制。方法：用液体或半固体培养法及流式细胞术测定血小板因子４对ＣＤ３４阳性脐血细胞的增殖与分化的作用。结果：血小反因子４可逆性地抑制ＣＤ３４阳性细胞向巨核细胞的发育。这种抑制可保留更多的巨核系干细胞并使其对５－氟尿嘧啶具有更强的抗性。血小板因子４还可抑制的血小板生成素诱导的巨核细胞生长。结论：血小板因子４通过调控血小板生成素的作用而使一些巨核细胞祖细胞 发育     

人脐带间充质干细胞分离培养及表面标志检测

 目的　探讨体外分离培养人脐带源间充质干细胞（hUCMSC）的方法,并检测hUCMSC的表面标志。方法　分离脐带华通胶（Wharton's jelly）,将其剪碎后利用组织块贴壁法培养获得hUCMSC,生长至一定密度后进行传代,采用流式细胞术检测第3代hUCMSC表面标志。结果　由人脐带华通胶可方便、有效地获得hUCMSC,其体外生长形态类似成纤维细胞,并可稳定增殖和传代。hUCMSC表面标志CD29、CD44、CD105高表达,而表面标志CD45、CD34、HLA-DR、HLA-G、CD80、CD86不表达。结论　利用人脐带华通胶组织块培养可有效获得hUCMSC,为组织工程提供丰富的细胞来源。     

Novel function of the chromosome 7 open reading frame 41 gene to promote leukemic megakaryocyte differentiation by modulating TPA-induced signaling

12-O-tetradecanoylphorbol-13-acetate (TPA) activates multiple signaling pathways, alters gene expression and causes leukemic cell differentiation. How TPA-induced genes contribute to leukemic cell differentiation remains elusive. We noticed that chromosome 7 open reading frame 41 (C7ORF41) was a TPA-responsive gene and its upregulation concurred with human megakaryocyte differentiation. In K562 cells, ectopic expression of C7ORF41 significantly increased CD61 expression, enhanced ERK and JNK signaling, and upregulated RUNX1 and FLI1, whereas C7ORF41 knockdown caused an opposite phenotype. These observations suggest that C7ORF41 may promote megakaryocyte differentiation partially through modulating ERK and JNK signaling that leads to upregulation of RUNX1 and FLI1. In supporting this, C7ORF41 overexpression rescued megakaryocyte differentiation blocked by ERK inhibition while JNK inhibition abrogated the upregulation of FLI1 by C7ORF41. Furthermore, we found that Y34F mutant C7ORF41 inhibited megakaryocyte differentiation. nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was the major activator of C7ORF41 that in turn repressed NF-κB activity by inhibiting its phosphorylation at serine 536, while MAPK/ERK was the potent repressor of C7ORF41. Finally, we showed that C7ORF41 knockdown in mouse fetal liver cells impaired megakaryocyte differentiation. Taken together, we have identified the function of a novel gene C7ORF41 that forms interplaying regulatory network in TPA-induced signaling and promotes leukemic and normal megakaryocyte differentiation.     

Preferential expression of the vasoactive intestinal peptide (VIP) receptor VPAC1 in human cord blood-derived CD34+CD38- cells: possible role of VIP as a growth-promoting factor for hematopoietic stem/progenitor cells.

Primitive hematopoietic progenitor cells such as severe combined immunodeficiency- repopulating cells and long-term culture-initiating cells are enriched in CD34+CD38- cells derived from various stem cell sources. In this study, to elucidate the features of such primitive cells at the molecular level, we tried to isolate genes that were preferentially expressed in umbilical cord blood (CB)-derived CD34+CD38- cells by subtractive hybridization. The gene for VPAC1 receptor, a receptor for the neuropeptide vasoactive intestinal peptide (VIP), was thereby isolated and it was shown that this gene was expressed in both CD34+CD38- and CD34+CD38+ CB cells and that the expression levels were higher in CD34+CD38- CB cells. Next, we assessed the effects of VIP on the proliferation of CD34+ CB cells using in vitro culture systems. In serum-free single-cell suspension culture, VIP enhanced clonal growth of CD34+ CB cells in synergy with FLT3 ligand (FL), stem cell factor (SCF), and thrombopoietin (TPO). In serum-free clonogenic assays, VIP promoted myeloid (colony-forming unit-granulocyte/macrophage (CFU-GM)) and mixed (CFU-Mix) colony formations. Furthermore, in Dexter-type long-term cultures, VIP increased colony-forming cells at week 5 of culture. These results suggest that VIP functions as a growth-promoting factor of CB-derived hematopoetic progenitor cells.     

A robust culture method for maintaining tumorigenic cancer stem cells in the hepatocellular carcinoma cell line Li‐7

Cancer tissues contain small populations of highly tumorigenic cells termed cancer stem cells (CSCs). Immortalized cell lines containing CSCs are valuable and powerful experimental tools for research into the characteristics of these stem cells. We previously reported that the hepatocellular carcinoma cell line Li‐7 includes abundant CD13⁺CD166^? CSCs; however, the number of these cells decreases after long‐term culture as a result of differentiation to non‐CSC populations. To ensure consistent and reproducible results in experiments using Li‐7 cells, it is important that the CSC population is maintained stably regardless of culture duration and passage. In the present study, we found that a commercially available culture medium for maintenance of embryonic stem cells and induced pluripotent stem cells, mTeSR1, effectively prevented spontaneous differentiation by CD13⁺CD166^? cells to CD13^?CD166⁺ cells and therefore maintained the CSC population in Li‐7 cell cultures. CD13⁺CD166^? CSCs maintained using this culture medium retained high tumorigenicity after transplantation into mice; they also showed the ability to differentiate in vitro into non‐CSC populations in RPMI‐1640 with 10% FBS medium. We analyzed gene expression profiles of CSC and non‐CSC populations in Li‐7 cultures using an RNA sequencing method. Genes such as FGFR, NOTCH1, and JAG1, that are associated with tumorigenicity and stemness, were upregulated in the CSC population. Our results suggest that CSCs can be maintained in immortalized cancer cell lines cultured over an extended period using a medium developed for culture of embryonic/induced pluripotent stem cells.     

Gene expression profiling of myelodysplastic CD34+ hematopoietic stem cells treated in vitro with decitabine

Abnormal gene promoter methylation contributes to deregulate gene expression of hematopoietic progenitors in myelodysplastic syndromes (MDS). We analyzed the gene expression profile of myelodysplastic and normal CD34+ hematopoietic stem cells (HSCs) treated in vitro with decitabine. We identified a list of candidate tumor suppressor genes, expressed at low levels in MDS HSCs and induced by hypomethylating treatment only in MDS, but not in normal HSCs. Real-time RT-PCR confirmed reduced CD9 expression in MDS CD34+ and bone marrow mononuclear cells, compared to normal controls. CD9 was specifically up-regulated by decitabine treatment in myelodysplastic CD34+ cells.     

急性白血病干细胞研究进展

白血病干细胞很可能是起源于发生了突变的正常造血干细胞。除与正常造血干细胞具有相同的CD34~ 、CD38~-、HLA-DR~-等细胞表型外,急性髓系白血病干细胞还具有自己特有的CD90~-、CD117~-、CD123~ 细胞表型、对热更敏感、持续活化的核因子kB以及比正常造血干细胞具有更高的自我更新和分化增殖能力等特征。核因子kB的异常活化、白细胞介素受体3以及PI3K信号传导等通路可能参与白血病干细胞生长和生存的调节,在白血病的发生与发展中起着重要的作用。     

Vitamin K2 induces apoptosis of a novel cell line established from a patient with myelodysplastic syndrome in blastic transformation.

We have previously reported that vitamin K2 (VK2) has a potent apoptosis inducing activity toward various types of primary cultured leukemia cells including acute myelogenous leukemia arising from myelodysplastic syndromes (MDS). We established a novel cell line, designated MDS-KZ, from a patient with MDS in blastic transformation, and further investigated the effects of VK2 using this novel cell line. MDS-KZ shows complex chromosomal anomaly including -4, 5q-, -7, 13q+, 20q-, consistent with that seen in the original patient. Culture of MDS-KZ cells in RPMI1640 medium containing 10% FBS lead to steady but very slow proliferation with a doubling time of 14 days. However, the cellular growth rate was significantly accelerated in the presence of various growth factors such as granulocyte colony-stimulating factor, stem cell factor, granulocyte-macrophage colony-stimulating factor, interleukin-3, and thrombopoietin. Most of the cultured cells show the morphological features of myeloblasts. They are positive for CD7, CD33, CD34, CD45, CD117, and HLA-DR. However, about 10% of the cells are more mature metamyelocytes and neutrophils with various dysplastic characteristics such as pseudo-Pelger nuclear anomaly and hypersegmentation, suggesting a potential for differentiation in this cell line. As previously reported for cultured primary leukemia cells, exposure to VK2, but not to VK1, resulted in induction of apoptosis of MDS-KZ cells in a dose-dependent manner (IC50: 5 microM). In addition, VK2 treatment induced down-regulation of BCL-2 and up-regulation of BAX protein expression with concomitant activation of caspase-3 (CPP32). A tetrapeptide functioning as antagonist of caspase-3, Ac-DEVD-H, suppressed the VK2-induced inhibition of cell growth, suggesting that caspase-3 is, at least in part, involved in VK2-induced apoptosis. These observations suggest that the MDS-KZ cell line can serve as a model for the study of the molecular mechanisms of VK2-induced apoptosis.     

无血清悬浮法培养MCF-7细胞系并筛选该细胞系中肿瘤干细胞相关亚群的初步研究

目的：研究无血清培养基悬浮培养MCF-7乳腺癌细胞系,筛选并鉴定MCF-7乳腺癌细胞系中的肿瘤干细胞相关亚群。方法：应用乳腺癌培养基在无血清的条件下悬浮培养MCF-7乳腺癌细胞系。通过无血清培养筛选乳腺癌细胞系肿瘤干细胞相关亚群,将其接种于含血清培养基,观察分化。应用单克隆形成实验、表面标志检测、HOECHST33342染色检测来确定培养出的细胞中肿瘤干细胞的比例及其培养后肿瘤干细胞含量的变化。结果：乳腺癌MCF-7细胞系中有约2.12%的肿瘤细胞在无血清培养基中能够存活、增殖,形成自由漂浮的细胞球。细胞球可连续传代,若重新接种于含血清培养基中可重新贴壁分化,贴壁分化后细胞形态与直接在含血清培养基中培养的MCF-7无明显差别。流式细胞仪表面标志检测,细胞球中约含83.13%表达CD24^-CD44^＋的细胞,HOECHST33342染色提示细胞球中约含10.06%的侧亚群（sidepopulation）细胞。结论：MCF-7细胞系可在含生长因子的无血清培养基中悬浮生长,并维持细胞系。该细胞系中含有比例较低的具有增殖和分化能力的乳腺癌干细胞相关亚群。表面标志以及HOECHST33342检测差异提示细胞球中仅约1/8细胞具有干细胞的功能。     

Establishment and phenotypic characterization of the first human pulmonary blastoma cell line

Background

Sarcomatoid carcinomas are a group of poorly differentiated carcinomas containing a sarcomatoid component with the presence of epithelial-mesenchymal transition.

Materials and methods

To obtain a stabilized cell line, three mediums were used: IMDM, BEBM and IMDM/BEBM. CD44, CD29, CD90, CD133, CD326 antigens, cytokeratins and vimentin were tested by flow cytometry and immunofluorescence assay. Side population, spheres formation, tumorigenicity in vitro and in vivo and cell cycle analysis were analyzed.

Results

At day of surgery, cytometric analysis revealed that CD133, CD90 and CD326 levels were very low, CD29 and CD44 were about 80%. After 30 days of culture, CD133 levels increased up to 30%, all cells expressed CD90 and vimentin markers and CD326 was lost. The cells grew only in IMDM/BEBM medium. The cell population was heterogeneous with epithelial and mesenchymal cells. After about 15-30 days, only fibroblast-like cells were observed. LC114 cells were not able to grow as spheres and they did not show a side-population phenotype. The cell cycle analysis confirmed an aneuploid population in the tissue and normal diploid population in cell line.

Conclusions

We selected, characterized and stabilized a primary cell line of human pulmonary blastoma by the expression both of stemness and differentiation markers and confirmed the presence of the marker CD133.     

Elevated TIM3+ hematopoietic stem cells in untreated myelodysplastic syndrome displayed aberrant differentiation,overproliferation and decreased apoptosis

TIM3, as a negative regulator of anti-tumor immunity, is highly expressed on LSCs, but not on normal HSCs. TIM3 on HSCs in MDS patients has not been clarified. Here, both the percentage of TIM3 on HSCs and the MFI of TIM3+ HSCs were higher in untreated MDS than control and were closed to AML, and excessive TIM3+ HSCs was closely related to clinical parameters: WPSS score, karyotype analysis, morphologic blasts, the number of cytopenia involving hematopoietic lineages, anemia and granulocytopenia. TIM3+ HSCs expressed lower CD11b, TpoR, EpoR, G-CSFR and Annexin V, and higher CD71 and GATA2. TIM3+ HSCs displayed aberrant differentiation, overproliferation and decreased apoptosis. TIM3 might be a promising marker for identifying malignant clone cells in MDS and a candidate for targeted therapy.     

Megakaryocytic growth factors: is there a new approach for management of thrombocytopenia in patients with malignancies?

C-mpl ligand acts primarily as a lineage-specific hematopoietic growth factor by promoting proliferation of megakaryocyte precursors and their differentiation into megakaryocytes and platelets. In addition to the ability of c-mpl ligand to support megakaryocytic development from CD34+ precursor cells, several lines of evidence also point to a stimulatory effect on hematopoietic stem cells. When recombinant thrombopoietin or pegylated megakaryocyte growth and development factor is administered to normal animals or humans, there is a dose-dependent increase in the platelet count. When administered following chemotherapy in animal models or humans, c-mpl ligands reduce the duration and sometimes the degree of thrombocytopenia. The issue of whether clinically relevant thrombocytopenia can be ameliorated has so far been more difficult to resolve. Because severe thrombocytopenia is not commonly seen with standard chemotherapy regimens, clinical studies examining c-mpl ligands for their ability to ameliorate chemotherapy-induced thrombocytopenia will focus on treatment of acute leukemias and bone marrow transplantation. The potential utility of c-mpl ligands for treatment of myelodysplastic syndromes, aplastic anemias, or in HIV infection, will have to be evaluated in the future. Possibly the greatest potential of thrombopoietic growth factors in the near future may be in transfusion medicine, to collect and to store platelets from healthy donors or in autologous settings.     

Functional cloning of IGFBP-3 from human microvascular endothelial cells reveals its novel role in promoting proliferation of primitive CD34+CD38- hematopoietic cells in vitro

Ex vivo expansion of hematopoietic stem cells (HSCs) has been investigated as a means of enhancing engraftment of transplantation therapies, but current ex vivo expansion methods typically result in a loss of functional stem cell activity. Factors that can selectively expand human HSCs remain elusive. Recently we have isolated three functionally distinct human brain microvascular endothelial cells (HBMVECs) that differ greatly in their ability to support in vitro proliferation of human umbilical cord blood (UBC) CD34+CD38-cells. Using these distinct HBMVEC populations, we have devised a cell-based functional cloning assay to identify a molecule(s) capable of facilitating expansion of HSCs in vitro. A gene encoded for IGFBP-3 (insulin-like growth factor binding protein-3) has been identified. IGFBP-3 mRNA and protein are differentially expressed in distinct HBMVEC populations. In vitro cell proliferation assay and CD34+CD38- immunophenotype analysis showed that the addition of an exogenous IGFBP-3 to cultures of purified CD34+/-CD38-Lin- cells (CD2/CD3/CD14/CD16/CD19/CD24/CD56/CD66b/GlyA depleted) enhanced proliferation of primitive hematopoietic cells with CD34+CD38- phenotype, suggesting that IGFBP-3 is capable of expanding primitive human blood cells. These expanded primitive blood cells were illustrated to maintain ability to generate functional progenitors. IGFBP-3 belongs to a family of high-affinity IGFBPs, which binds to IGFs and modulates their actions. IGFBP-3 appears to have intrinsic bioactivity that is independent of IGF binding. We are currently exploring the underlying mechanism by which IGFBP-3 modulates proliferation of primitive hematopoietic cells, and the potential of IGFBP-3 to expand pluripotent human repopulating cells capable of hematopoietic reconstitution of irradiated NOD/SCID recipients.     

Expression of CD133 Cancer Stem Cell Marker in IDH-Mutant and IDH-wildtype (Isocitrate Dehydrogenase) Astrocytoma

Objective: This study evaluated the differences between IDH1-R132H and CD133 expression in different categories of  astrocytoma. Material and methods: This study used a cross-sectional design.  Sixty-seven paraffin embedded block of Diffuse Astrocytoma (DA), Anaplastic Astrocytoma (AA) and Glioblastoma (GB) were assessed using using the monoclonal antibody IDH1-R132H and Rabbit polyclonal antibody CD133. Results: It was found that there was a significant relationship between the expression of IDH1-R132H and CD133 in DA, AA and GB (p<0.001). Astrocytoma with IDH-mutant molecular status will express more markers of cancer stem cell CD133 than IDH-wildtype. Conclusion: The IDH1-R132H and CD133 can provide predictive value on treatment success, disease prognosis, recurrence and can be considered as target combination therapy with chemotherapy.     

人尿源性干细胞的原代培养

目的：建立一种人尿源性干细胞（hUSCs）的原代分离培养及保存方法,为hUSCs的应用奠定基础。方法：取10例成人健康志愿者的尿液分别进行hUSCs原代培养,台盼蓝染色法比较不同冻存液配方复苏后的细胞存活率,进而确定hUSCs的最佳冻存液配方;采用四甲基噻唑蓝（MTT）法检测hUSCs细胞的增殖活性;流式细胞术测定间充质干细胞表面抗原CD44和CD90的表达情况。结果：10例健康成人志愿者中6例成功提取了hUSCs并体外培养形成集落;台盼蓝染色法确定配比为DMSO∶FBS∶hUSCs培养基=1∶4∶5的冻存液细胞存活率最高,与其他组比较差异具有统计学意义（P < 0.05）;MTT法检测显示hUSCs生长曲线呈S形且具有良好的增殖活性;流式细胞术鉴定干细胞表面抗原CD44和CD90呈阳性表达。结论：成功建立了一种人尿源性干细胞的原代分离培养及保存方法。     

Impaired stem cell function of CD34+ cells selected by two different immunomagnetic beads systems.

We have been investigating the hematopoietic stem cell (HSC) activity of peripheral blood-derived CD34(+) cells selected by two different laboratory immunomagnetic beads systems (MiniMACS and Isolex 50). In this study, the quality of purified CD34(+) cells was directly compared using clonal cell culture, a cobblestone area-forming cell (CAFC) assay, and an in vivo severe combined immunodeficiency (SCID)-repopulating cell (SRC) assay. It was found that CD34(+) cells selected by these two immunomagnetic methods showed a reduced yield of colony-forming cells and CAFCs compared with cells enriched by the StemSep device (a negative selection method). However, these CD34(+) cells still showed significant SRC activity, including multilineage lymphomyeloid reconstitution. The percentage of human CD45(+) cells in murine bone marrow after transplanting 5 x 10(5) CD34(+) cells selected by the Isolex 50 was significantly lower than after transplanting cells selected by the MiniMACS or the StemSep. Our findings clearly demonstrated that CD34(+) cells selected by the MiniMACS system had superior HSC functions, including SRC activity, compared with cells separated by the Isolex 50 system. More detailed functional analysis of immunomagnetically separated CD34(+) cells may provide useful knowledge for basic research on HSCs as well as for clinical HSC transplantation.