Tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment (TME) and are critical for cancer initiation and progression. MicroRNAs (miRNAs) could notably influence the phenotype of TAMs through various targets and signal pathways during cancer progression due to their post-transcriptional regulation. In this review, we discuss mainly the regulatory function of miRNAs on macrophage differentiation, functional polarization, and cellular crosstalk. Firstly, during the generation process, miRNAs take part in the differentiation from myeloid cells to mature macrophages, and this maturation process directly influences their recruitment into the TME, attracted by tumor cells. Secondly, macrophages in the TME can be either tumor-promoting or tumor-suppressing, depending on their functional polarization. Large numbers of miRNAs can influence the polarization of macrophages, which is crucial for tumor progression, including tumor cell invasion, intravasation, extravasation, and premetastatic site formation. Thirdly, crosstalk between tumor cells and macrophages is essential for TME formation and tumor progression, and miRNAs can be the mediator of communication in different forms, especially when encapsulated in microvesicles or exosomes. We also assess the potential value of certain macrophage-related miRNAs (MRMs) as diagnostic and prognostic markers, and discuss the possible development of MRM-based therapies.
Cell Communication ; Cell Differentiation ; Cell Polarity ; Humans ; Macrophages/physiology* ; MicroRNAs/physiology* ; Myeloid Cells/cytology* ; Neoplasms/therapy* ; Tumor Microenvironment

Glioma is one of the most common primary tumors in the human brain with poor prognosis. The local and systemic immunosuppressive environment created by glioma cells enables them to evade immunosurveillance. Myeloid-derived suppressor cells (MDSCs) are a critical component of the immunosuppression system. They are a heterogeneous cell population composed of early myeloid progenitor cells and precursor cells. Although the cells are diverse in phenotypes and functions, they all have strong immunosuppressive functions. MDSCs are extensively infiltrated into tumor tissues and play an important role in the glioma immunosuppressive microenvironment, which also hinders the immunotherapeutic effects of glioma. This article will review the phenotypic characteristics of MDSCs in the glioma microenvironment and their role in the progression of glioma. It is of positive significance to better understand the pathogenesis of glioma and explore effective comprehensive treatments.
Glioma ; pathology ; Humans ; Immune Tolerance ; Myeloid-Derived Suppressor Cells ; cytology ; Tumor Microenvironment

To investigate the effects of adenosine triphosphate (ATP) on expression of inflammatory factors induced by lipopolysaccharide (LPS) in endothelial progenitor cells (EPCs), and to elucidate the possible mechanisms.
 Methods: Mononuclear cells were isolated from human umbilical cord blood by density gradient centrifugation, RT-PCR was performed to detect the expression of inflammatory factors induced by LPS (1 mg/mL) in EPCs, the effect of low concentration (5 μmol/L) of ATP on expression of IL-1β, MCP-1 and ICAM-1, and the effect of different concentrations (5, 50 μmol/L) of ATP on the expression of Toll-like receptor (TLR) 4, myeloid differentiation primary response protein 88 (MyD88) and CD14. Western blot was performed to detect expression of TLR4 regulated proteins MyD88 and CD14 or to detect the low concentration (1, 5 μmol/L) of ATP on the expression of TLR4, MyD88 and CD14 and the NF-κB signaling pathway.
 Results: EPCs highly expressed TLR4, and its ligand LPS (1 mg/mL) significantly upregulated mRNA expression of IL-1β, MCP-1 and ICAM-1 and protein expression of MyD88 and CD14 in a time-dependent manner (P<0.01), accompanied by activation of ERK and NF-κB signal pathway. ATP at low concentration (5 μmol/L) significantly inhibited LPS-induced mRNA expression of IL-1β, MCP-1 and ICAM-1(P<0.05), downregulated the LPS-induced protein expression of TLR4, MyD88 and CD14 in EPCs (P<0.05), and suppressed LPS-induced activation of NF-κB signaling pathway (P<0.05).
 Conclusion: ATP at low concentration may suppress LPS-induced expression of inflammatory factors in EPCs through negative regulation of the TLR4 signaling pathway.
Adenosine Triphosphate ; pharmacology ; Endothelial Progenitor Cells ; drug effects ; Gene Expression Regulation ; drug effects ; Humans ; Leukocytes, Mononuclear ; cytology ; Lipopolysaccharide Receptors ; genetics ; Lipopolysaccharides ; pharmacology ; Myeloid Differentiation Factor 88 ; genetics ; NF-kappa B ; metabolism ; Signal Transduction ; drug effects ; Toll-Like Receptor 4 ; genetics

BACKGROUNDTriggering receptor expressed on myeloid cell-1 (TREM-1) may play a vital role in mammalian target of rapamycin (mTOR) modulation of CD8+ T-cell differentiation through the transcription factors T-box expressed in T-cells and eomesodermin during the immune response to invasive pulmonary aspergillosis (IPA). This study aimed to investigate whether the mTOR signaling pathway modulates the proliferation and differentiation of CD8+ T-cells during the immune response to IPA and the role TREM-1 plays in this process.

METHODSCyclophosphamide (CTX) was injected intraperitoneally, and Aspergillus fumigatus spore suspension was inoculated intranasally to establish the immunosuppressed IPA mouse model. After inoculation, rapamycin (2 mg.kg-1.d-1) or interleukin (IL)-12 (5 μg/kg every other day) was given for 7 days. The number of CD8+ effector memory T-cells (Tem), expression of interferon (IFN)-γ, mTOR, and ribosomal protein S6 kinase (S6K), and the levels of IL-6, IL-10, galactomannan (GM), and soluble TREM-1 (sTREM-1) were measured.

RESULTSViable A. fumigatus was cultured from the lung tissue of the inoculated mice. Histological examination indicated greater inflammation, hemorrhage, and lung tissue injury in both IPA and CTX + IPA mice groups. The expression of mTOR and S6K was significantly increased in the CTX + IPA + IL-12 group compared with the control, IPA (P = 0.01; P= 0.001), and CTX + IPA (P = 0.034; P= 0.032) groups, but significantly decreased in the CTX + IPA + RAPA group (P < 0.001). Compared with the CTX + IPA group, the proportion of Tem, expression of IFN-γ, and the level of sTREM-1 were significantly higher after IL-12 treatment (P = 0.024, P= 0.032, and P= 0.017, respectively), and the opposite results were observed when the mTOR pathway was blocked by rapamycin (P < 0.001). Compared with the CTX + IPA and CTX + IPA + RAPA groups, IL-12 treatment increased IL-6 and downregulated IL-10 as well as GM, which strengthened the immune response to the IPA infection.

CONCLUSIONSmTOR modulates CD8+ T-cell differentiation during the immune response to IPA. TREM-1 may play a vital role in signal transduction between mTOR and the downstream immune response.

Animals ; CD8-Positive T-Lymphocytes ; cytology ; metabolism ; Cell Differentiation ; genetics ; physiology ; Female ; Interferon-gamma ; metabolism ; Invasive Pulmonary Aspergillosis ; metabolism ; Lymphocyte Activation ; genetics ; physiology ; Mice ; Mice, Inbred BALB C ; Myeloid Cells ; cytology ; metabolism ; Ribosomal Protein S6 Kinases ; metabolism ; TOR Serine-Threonine Kinases ; genetics ; metabolism ; Tissue Culture Techniques

No abstract available.
Adult ; Antigens, CD4/*metabolism ; Antigens, CD56/*metabolism ; Bone Marrow/metabolism/pathology ; Dendritic Cells/cytology/*metabolism ; Diagnostic Errors ; Exons ; Female ; Flow Cytometry ; Gene Rearrangement ; Hematologic Neoplasms/diagnosis ; Histone-Lysine N-Methyltransferase/genetics ; Humans ; Immunohistochemistry ; In Situ Hybridization, Fluorescence ; Leukemia, Myeloid, Acute/*diagnosis ; Male ; Middle Aged ; Myeloid-Lymphoid Leukemia Protein/genetics ; Real-Time Polymerase Chain Reaction ; Sequence Analysis, DNA ; Transcription Factors/genetics ; Translocation, Genetic

BRG1 (Brahma-related gene 1, BRG1) is the ATPase subunit of SWI/SNF chromatin remodeling complexes, which plays an important role in cell cycle regulation, DNA repair and tumor development. Unlike the evidence as tumor suppressor genes in the past reports, latest researches show that BRG1 plays an important role in sustaining the growth of leukemia cells in acute myeloid leukemia, and these effects on normal hematopoietic stem cells are dispensable. Further studies of the role and mechanism of BRG1 in acute myeloid leukemia will contribute to the development of a new and promising targeted therapy strategy. This article reviews the role of BRG1 on leukemia cells and leukemia stem cells in AML and discusses the related mechanism, which providing some reference for the targeted treatment strategy of AML.
Chromatin ; Chromatin Assembly and Disassembly ; DNA Helicases ; genetics ; Humans ; Leukemia, Myeloid, Acute ; genetics ; Neoplastic Stem Cells ; cytology ; Nuclear Proteins ; genetics ; Transcription Factors ; genetics

OBJECTIVETo explore the autophagy activity of CD34+ cells in bone marrow of MDS patients and its clinical significance.

METHODSThe activity of autophagy in bone marrow CD34+ cells from 20 MDS patients, 20 non-malignant anemia patients and 5 AML patients admitted in our hospital from October 2012 to March 2014 was detected by flow cytometry (FCM).

RESULTSThe autophagy activity in low risk MDS patients and non-malignant anemia patients were both significantly higher than that in both high risk MDS and AML patients (P<0.05), and more interestingly, the autophagy activity in MDS negatively correlated with World Health Organization classification-based prognostic system (WPSS) score (r=-0.877) .

CONCLUSIONThe autophagy activity CD34+ cells in the patients with MDS is higher than that in AML patients, and negatively correlated with WPSS scores, indicating that the decrease of autophagy activity maybe accelerate the genesis and development of MDS and relate with the prognosis of MDS patients.

Antigens, CD34 ; metabolism ; Autophagy ; Bone Marrow Cells ; cytology ; pathology ; Flow Cytometry ; Humans ; Leukemia, Myeloid, Acute ; pathology ; Myelodysplastic Syndromes ; pathology ; Prognosis

Myelodysplastic Syndrome (MDS) is a group of clonal disorders of hematopoietic stem cells characterized by peripheral cytopenia, ineffective hematopoiesis, morphologically apparent multilineage dysplasia, and enhanced risk of evolution towards acute myeloid leukemia (AML). Most of the research findings have verified the abnormal proliferation and differentiation of hematopoietic cells in MDS. The defects of cellular and molecular factors such as transcription factors (GATA-1~GATA-3, FOG1, Pu.1), growth factors (Epo, G-CSF, GM-CSF) and anti-apoptosis genes ultimately affect the cell cycle regulation and mismatch repair of DNA, changes of hematopoietic microenvironment and immune response. These defects result in ineffective hematopoiesis and dysplasia.
Apoptosis ; Cell Differentiation ; Cell Proliferation ; Hematopoietic Stem Cells ; cytology ; Humans ; Intercellular Signaling Peptides and Proteins ; metabolism ; Leukemia, Myeloid, Acute ; Myelodysplastic Syndromes ; Transcription Factors ; metabolism

BACKGROUNDSteady-state bone marrow (SS-BM) and granulocyte colony-stimulating growth factor-primed BM/peripheral blood stem-cell (G-BM/G-PBSC) are the main stem-cell sources used in allogeneic hematopoietic stem-cell transplantation. Here, we evaluated the treatment effects of SS-BM and G-BM/G-PBSC in human leucocyte antigen (HLA)-identical sibling transplantation.

METHODSA total of 226 patients (acute myelogenous leukemia-complete remission 1, chronic myelogenous leukemia-chronic phase 1) received SS-BM, G-BM, or G-PBSC from an HLA-identical sibling. Clinical outcomes (graft-versus-host disease [GVHD], overall survival, transplant-related mortality [TRM], and leukemia-free survival [LFS]) were analyzed.

RESULTSWhen compared to SS-BM, G-BM gave faster recovery time to neutrophil or platelet (P < 0.05). Incidence of grade III-IV acute GVHD and extensive chronic GVHD (cGVHD) was lower than seen with SS-BM (P < 0.05) and similar to G-PBSC. Although the incidence of cGVHD in the G-BM group was similar to SS-BM, both were lower than G-PBSC (P < 0.05). G-BM and G-PBSC exhibited similar survival, LFS, and TRM, but were significantly different from SS-BM (P < 0.05). There were no significant differences in leukemia relapse rates among the groups (P > 0.05).

CONCLUSIONSG-CSF-primed bone marrow shared the advantages of G-PBSC and SS-BM. We conclude that G-BM is an excellent stem-cell source that may be preferable to G-PBSC or SS-BM in patients receiving HLA-identical sibling hematopoietic stem-cell transplantation.

Adolescent ; Adult ; Aged ; Bone Marrow ; drug effects ; Bone Marrow Transplantation ; methods ; Child ; Female ; Granulocyte Colony-Stimulating Factor ; pharmacology ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; therapy ; Leukemia, Myeloid, Acute ; therapy ; Male ; Middle Aged ; Retrospective Studies ; Stem Cells ; cytology ; Young Adult

Acute graft-versus-host disease (aGVHD) is a serious complication after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the mechanisms of aGVHD are not well understood. We aim to investigate the roles of the three angiogenic factors: angiopoietin-1 (Ang-1), Ang-2 and vascular endothelial growth factor (VEGF) in the development of aGVHD. Twenty-one patients who underwent allo-HSCT were included in our study. The dynamic changes of Ang-1, Ang-2 and VEGF were monitored in patients before and after allo-HSCT. In vitro, endothelial cells (ECs) were treated with TNF-β in the presence or absence of Ang-1, and then the Ang-2 level in the cell culture medium and the tubule formation by ECs were evaluated. After allo-HSCT, Ang-1, Ang-2 and VEGF all exhibited significant variation, suggesting these factors might be involved in the endothelial damage in transplantation. Patients with aGVHD had lower Ang-1 level at day 7 but higher Ang-2 level at day 21 than those without aGVHD, implying that Ang-1 may play a protective role in early phase yet Ang-2 is a promotion factor to aGVHD. In vitro, TNF-β promoted the release of Ang-2 by ECs and impaired tubule formation of ECs, which were both weakened by Ang-1, suggesting that Ang-1 may play a protective role in aGVHD by influencing the secretion of Ang-2, consistent with our in vivo tests. It is concluded that monitoring changes of these factors following allo-HSCT might help to identify patients at a high risk for aGVHD.
Acute Disease ; Adolescent ; Adult ; Angiogenesis Inducing Agents ; immunology ; metabolism ; pharmacology ; Angiopoietin-1 ; genetics ; immunology ; pharmacology ; Angiopoietin-2 ; genetics ; immunology ; pharmacology ; Antineoplastic Agents ; therapeutic use ; Female ; Gene Expression Regulation, Neoplastic ; Graft vs Host Disease ; genetics ; immunology ; pathology ; Hematopoietic Stem Cell Transplantation ; Human Umbilical Vein Endothelial Cells ; cytology ; drug effects ; immunology ; Humans ; Leukemia, Myeloid ; genetics ; immunology ; pathology ; therapy ; Lymphoma, Non-Hodgkin ; genetics ; immunology ; pathology ; therapy ; Male ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; genetics ; immunology ; pathology ; therapy ; Retrospective Studies ; Signal Transduction ; Transplantation, Homologous ; Tumor Necrosis Factor-alpha ; pharmacology ; Vascular Endothelial Growth Factor A ; genetics ; immunology