Circulating hematopoietic stem cells, endothelial progenitor cells and cancer stem cells in hepatocellular carcinoma patients: contribution to diagnosis and prognosis

Increasing evidence reveals that lysophosphatidylcholine (LPC) is closely related to endothelial dysfunction. The present study aimed to investigate the mechanism of LPC in inhibiting the proangiogenesis and vascular inflammation of human endothelial progenitor cells (EPCs) derived from CD34+ cells. The early EPCs were derived from CD34+ hematopoietic stem cells whose purity was identified using flow cytometry analysis. The surface markers (CD34, KDR, CD31; VE-cadherin, vWF, eNOS) of EPCs were examined by flow cytometry analysis and immunofluorescence. RT-qPCR was used to detect the mRNA expression of inflammatory cytokines (CCL2, IL-8, CCL4) and genes associated with angiogenesis (VEGF, ANG-1, ANG-2) in early EPCs after treatment of LPC (10 μg/ml) or phosphatidylcholine (PC, 10 μg/ml, control). The angiogenesis of human umbilical vein endothelial cells (HUVECs) incubated with the supernatants of early EPCs was detected by a tube formation assay. The mRNA and protein levels of key factors on the PKC pathway (phosphorylated PKC, TGF-β1) were measured by RT-qPCR and western blot. The localization of PKC-β1 in EPCs was determined by immunofluorescence staining. We found that LPC suppressed the expression of CCL2, CCL4, ANG-1, ANG-2, promoted IL-8 expression and had no significant effects on VEGF expression in EPCs. EPCs promoted the angiogenesis of HUVECs, which was significantly inhibited by LPC treatment. Moreover, LPC was demonstrated to promote the activation of the PKC signaling pathway in EPCs. In conclusion, LPC inhibits proangiogenesis of human endothelial progenitor cells derived from CD34+ hematopoietic stem cells.

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Endothelial Progenitor Cell Marker CD133 Identifies Tumor Endothelium

Blood ◽

10.1182/blood.v112.11.5449.5449 ◽

2008 ◽

Vol 112 (11) ◽

pp. 5449-5449

Author(s):

Muhamed Baljevic ◽

Sergey V Shmelkov ◽

Daniel J Nolan ◽

Andrea T Hooper ◽

Adilia Hormigo ◽

...

Keyword(s):

Stem Cells ◽

Endothelial Cells ◽

Cancer Stem Cells ◽

Brain Tumors ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Tumor Vasculature ◽

Significant Heterogeneity ◽

Endothelial Progenitor ◽

Hematopoietic Stem

Abstract CD133, a pentaspan surface antigen, is considered a marker of tissue-specific stem cells, including hematopoietic stem cells and endothelial progenitors. We and others have previously shown that CD133 expression is high on endothelial progenitor cells; that it is downregulated during their differentiation and that it is not found on mature endothelium. In addition, CD133+ cells in brain tumors were shown to exhibit features of cancer stem cells. Recent report showed that CD133+ tumor cells are located in perivascular niches in astrocytomas and glioblastomas. It was also demonstrated that in glioblastomas, CD133+ cancer stem cells are tightly associated with tumor vasculature and that signals from endothelial cells are the key factors in self-renewal and proliferation of cancer stem cells. However, the contribution of CD133+ endothelial progenitor cells to tumor angiogenesis remains unknown. We sought to investigate the role of CD133+ cells in human brain tumors and their relation to endothelial progenitor cells and to the mature endothelium. To this end we examined tumor samples resected from patients with glioblastomas. Histological and immunohistochemical analyses revealed that CD133+ cells in these tumors are predominantly endothelial cells as demonstrated by co-staining with CD31 and CD133. We further analyzed a population of endothelial cells using multicolor flow cytometry analysis and we demonstrated that on average 60% of endothelial cells, as defined by the expression of CD31 and VE-cadherin, also express CD133. However, we also found significant heterogeneity between glioblastomas obtained from different patients. Additionally, CD133 was not expressed on CD45−CD31+ subpopulation in meningiomas. Taken together, we demonstrated that high percentage of endothelial cells in glioblastomas expresses CD133, while CD133 could also be found on other cell types within the tumor. Furthermore, our data suggest that tumor vasculature might be enriched with bone marrow derived hemangiogenic progenitors.

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Very Small Embryonic-Like Stem Cells, Endothelial Progenitor Cells, and Different Monocyte Subsets Are Effectively Mobilized in Acute Lymphoblastic Leukemia Patients after G-CSF Treatment

Stem Cells International ◽

10.1155/2018/1943980 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 4

Author(s):

Andrzej Eljaszewicz ◽

Lukasz Bolkun ◽

Kamil Grubczak ◽

Malgorzata Rusak ◽

Tomasz Wasiluk ◽

...

Keyword(s):

Stem Cells ◽

Stem Cell ◽

Acute Lymphoblastic Leukemia ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Lymphoblastic Leukemia ◽

Monocyte Subsets ◽

Endothelial Progenitor ◽

Hematopoietic Stem ◽

Cd34 Cells

Background. Acute lymphoblastic leukemia (ALL) is a malignant disease of lymphoid progenitor cells. ALL chemotherapy is associated with numerous side effects including neutropenia that is routinely prevented by the administration of growth factors such as granulocyte colony-stimulating factor (G-CSF). To date, the effects of G-CSF treatment on the level of mobilization of different stem and progenitor cells in ALL patients subjected to clinically effective chemotherapy have not been fully elucidated. Therefore, in this study we aimed to assess the effect of administration of G-CSF to ALL patients on mobilization of other than hematopoietic stem cell (HSCs) subsets, namely, very small embryonic-like stem cells (VSELs), endothelial progenitor cells (EPCs), and different monocyte subsets. Methods. We used multicolor flow cytometry to quantitate numbers of CD34+ cells, hematopoietic stem cells (HSCs), VSELs, EPCs, and different monocyte subsets in the peripheral blood of ALL patients and normal age-matched blood donors. Results. We showed that ALL patients following chemotherapy, when compared to healthy donors, presented with significantly lower numbers of CD34+ cells, HSCs, VSELs, and CD14+ monocytes, but not EPCs. Moreover, we found that G-CSF administration induced effective mobilization of all the abovementioned progenitor and stem cell subsets with high regenerative and proangiogenic potential. Conclusion. These findings contribute to better understanding the beneficial clinical effect of G-CSF administration in ALL patients following successful chemotherapy.

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Hemangiogenic Role of ELF4 in Bone Marrow Post Myeloablation.

Blood ◽

10.1182/blood.v108.11.1783.1783 ◽

2006 ◽

Vol 108 (11) ◽

pp. 1783-1783

Author(s):

Mariela Sivina ◽

Takeshi Yamada ◽

Natalie Dang ◽

H. Daniel Lacorazza

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Endothelial Cells ◽

Hematopoietic Stem Cells ◽

Blood Vessels ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Bone Marrow Cells ◽

Hematopoietic Stem ◽

Huvec Cells

Abstract Bone marrow suppression is an important cause of death in patients exposed to radiation or in cancer patients treated with conventional chemotherapeutic agents. Myeloablative treatments (i.e. 5-fluorouracil administration) lead to apoptosis of blood forming cells and to regression of blood vessels in bone marrow. It is well known that hematological recovery post-bone marrow insult depends on the capacity of hematopoietic stem cells to regenerate the entire hematopoietic system, however, the transcriptional machinery involved in the regeneration of sinusoidal blood vessels in bone marrow from endothelial progenitor cells is largely unknown. Endothelial cells express the Tie2 receptor tyrosine kinase (a.k.a. Tek), which is involved in the angiogenic remodeling and vessel stabilization. Gene targeting of Tie2 showed that it is not required for differentiation and proliferation of definitive hematopoietic lineages in the embryo although Tie2 is needed during postnatal bone marrow hematopoiesis. ELF is a subgroup of the ETS family of transcription factors composed by ELF1, ELF2 (a.k.a. NERF), ELF3, ELF4 (a.k.a. MEF) and ELF5. ELF1 and ELF2 have been shown to regulate Tie2 expression in vitro. Recently we showed that ELF4 modulates the exit of hematopoietic stem cells (HSC) from quiescence (Lacorazza et al., Cancer Cell2006, 9:175–187). Given the high homology between ELF1 and ELF4 and the same origin of HSC and endothelial progenitor cells, we hypothesize that ELF4 regulates proliferation and Tie2 expression of endothelial cells. We used a luciferase gene reporter system in COS-7 and HEK cells to examine the capacity of ELF proteins to activate Tie2. ELF4 is the strongest activator of Tie2 expression following the hierarchy ELF4>ELF1>ELF2 variant 1>ELF2 variant 2. Site directed mutagenesis of each of the five ETS-binding sites (EBS) present in the Tie2 promoter shows that ELF4 binds preferentially to EBS 1, 3 and 5. Binding of ELF4 to the Tie2 promoter was confirmed by chromatin immunoprecipitation and EMSA. Although Elf1 gene expression is essentially normal in Elf4−/− bone marrow cells collected after 5-FU treatment, we detected diminished Tie2 expression compared to Elf4+/+ bone marrow cells. The association of this effect to human endothelial cells derived from umbilical cord (HUVEC cells) was investigated. All-trans retinoic acid (ATRA) and vascular-endothelial growth factor (VEGF) induced ELF4 expression in HUVEC cells in a dose and time dependent manner which was followed by increased Tie2 expression, suggesting that expression of ELF4 is modulated by angiogenic signals. Moreover, endothelial cells treated with ATRA showed rapid wound colonization in a wound assay. Expression of the pan-endothelial marker MECA-32 was determined by immunohistochemistry to correlate Tie2 with the regeneration of blood vessels: myeloablated Elf4−/− femurs exhibited a reduction of MECA-32 positive arterioles. Finally, temporal and spatial expression of Tie2 during hematological recovery post ablation was measured in bone marrow using transgenic Tie2-LacZ mice crossed to Elf4−/− mice. Collectively, our data suggests that ELF4 regulates Tie2 expression in endothelial cells but most importantly their proliferative capacity in response to angiogenic signals.

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Identification of functional endothelial progenitor cells suitable for the treatment of ischemic tissue using human umbilical cord blood

Blood ◽

10.1182/blood-2006-10-047092 ◽

2007 ◽

Vol 110 (1) ◽

pp. 151-160 ◽

Cited By ~ 91

Author(s):

Masumi Nagano ◽

Toshiharu Yamashita ◽

Hiromi Hamada ◽

Kinuko Ohneda ◽

Ken-ichi Kimura ◽

...

Keyword(s):

Stem Cells ◽

Cord Blood ◽

Progenitor Cells ◽

Endothelial Progenitor Cells ◽

Umbilical Cord ◽

Umbilical Cord Blood ◽

Human Umbilical Cord ◽

Aldh Activity ◽

Endothelial Progenitor ◽

Hematopoietic Stem

Umbilical cord blood (UCB) has been used as a potential source of various kinds of stem cells, including hematopoietic stem cells, mesenchymal stem cells, and endothelial progenitor cells (EPCs), for a variety of cell therapies. Recently, EPCs were introduced for restoring vascularization in ischemic tissues. An appropriate procedure for isolating EPCs from UCB is a key issue for improving therapeutic efficacy and eliminating the unexpected expansion of nonessential cells. Here we report a novel method for isolating EPCs from UCB by a combination of negative immunoselection and cell culture techniques. In addition, we divided EPCs into 2 subpopulations according to the aldehyde dehydrogenase (ALDH) activity. We found that EPCs with low ALDH activity (Alde-Low) possess a greater ability to proliferate and migrate compared to those with high ALDH activity (Alde-High). Moreover, hypoxia-inducible factor proteins are up-regulated and VEGF, CXCR4, and GLUT-1 mRNAs are increased in Alde-Low EPCs under hypoxic conditions, while the response was not significant in Alde-High EPCs. In fact, the introduction of Alde-Low EPCs significantly reduced tissue damage in ischemia in a mouse flap model. Thus, the introduction of Alde-Low EPCs may be a potential strategy for inducing rapid neovascularization and subsequent regeneration of ischemic tissues.

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