Expression Changes of Hypoxia-Inducible Factor-1α in G-CSF Induced Hematopoietic Stem Cell Mobilization / 中国实验血液学杂志

OBJECTIVE@#To investigate the expression and its relative mechanism of hypoxia-inducible factor-1α(HIF-1α) in bone marrow(BM) of mice during G-CSF mobilization of hematopoietic stem cells (HSC) .@*METHODS@#Flow cytometry was used to detect the proportion of Lin-Sca-1+ c-kit+ (LSK) cells in peripheral blood of C57BL/6J mice before and after G-CSF mobilization. And the expression of HIF-1α and osteocalcin (OCN) mRNA and protein were detected by RQ-PCR and immunohistochemistry. The number of osteoblasts in bone marrow specimens of mice was counted under the microscope.@*RESULTS@#The proportion of LSK cells in peripheral blood began to increase at day 4 of G-CSF mobilization, and reached the peak at day 5, which was significantly higher than that of control group (P<0.05). There was no distinct difference in the expression of HIF-1α mRNA between bone marrow nucleated cells and osteoblasts of steady-state mice (P=0.073), while OCN mRNA was mainly expressed in osteoblasts, which was higher than that in bone marrow nucleated cells (P=0.034). After mobilization, the expression level of HIF-1α increased, but OCN decreased, and the number of endosteum osteoblasts decreased. The change of HIF-1α expression was later than that of OCN and was consistent with the proportion of LSK cells in peripheral blood.@*CONCLUSION@#The expression of HIF-1α in bone marrow was increased during the mobilization of HSC mediated by G-CSF, and one of the mechanisms may be related to the peripheral migration of HSC induced by osteoblasts inhibition.

Avaliação dos efeitos modulatórios da hematopoese no envelhecimento: Papel das células tronco mesenquimais medulares / Evaluation of the modulatory effects of hematopoiesis during aging: Role of bone marrow mesenchymal stem cells

O envelhecimento é um processo fisiológico que traz consigo uma série de alterações no organismo que se estendem até o nível molecular. Diante disto, este é um processo complexo que afeta diversos tecidos, sendo um deles o hematopoético, local onde, através de interações da Célula Tronco Hematopoética (CTH) com o ambiente ao seu redor, incluindo a Célula Tronco Mesenquimal (CTM), ocorre a hematopoese. Embora já sejam descritas na literatura algumas alterações na medula óssea consequentes do envelhecimento, os mecanismos por trás de tais mudanças permanecem elusivas, principalmente no âmbito das interações celulares ocorrentes na medula óssea. Portanto, este trabalho buscou investigar como o envelhecimento afeta a regulação hematopoética no contexto de sua relação com as CTM medulares. Para esta pesquisa, foram utilizados camundongos machos isogênicos da linhagem C57BL/6, dividindoos em grupos conforme sua idade: jovens (3 ­ 5 meses) e idosos (18 ­ 19 meses). Foi realizada a caracterização do modelo através de aspectos físicos como consumo proteico, variação de peso, entre outros, seguido de avaliação bioquímica e hematológica. Adicionalmente, foram coletadas células medulares e, posteriormente, realizado o isolamento das CTMs. Para estudar a relação destas células com a hematopoese, foram realizados ensaios in vitro utilizando a linhagem celular leucêmica C1498 (TIB-49™, ATCC®) mantidas em contato com o sobrenadante das CTMs isoladas. Quanto aos parâmetros bioquímicos, os animais idosos apresentaram menores níveis de albumina, aspartato alanina transferase (ALT) e de triglicerídeos quando comparados aos animais jovens. Contrariamente, os animais idosos apresentaram um maior nível de colesterol. Na avaliação hematológica, foi constatado pelo hemograma que os animais idosos apresentaram valores comparáveis aos animais jovens, todavia, o mielograma mostrou menor celularidade geral, seguido de menor número de células da linhagem eritroide e maior número de precursores granulocíticos. Através da imunofenotipagem, foi revelado um maior número de CTHs e de precursores grânulosmonocíticos na medula de animais idosos quando comparado aos jovens, e uma menor frequência de progenitores linfoides. Na imunofenotipagem de sangue periférico de animais idosos houve uma redução no número de linfócitos B e de eritrócitos, e aumento na população de células natural killers. Na imunofenotipagem de CTMs, o marcador CD73 apresentou menor expressão nos animais idosos. Avaliando o secretoma destas células estromais, foram encontrados no sobrenadante de CTMs de animais idosos aumentos significativos nas concentrações de CXCL12 e SCF e redução de IL-11. No âmbito molecular, as CTMs de animais idosos apresentaram aumento na expressão de Akt1, Nos e Ppar-γ, e redução na expressão de Csf3 e Cdh2. Adicionalmente, quando comparado a ação das CTMs de animais idosos em relação as CTMs de animais jovens, observou-se que CTMs de animais idosos foram capazes de aumentar a expressão de Sox2, Pou5f1 e Nanog e diminuir a expressão de Cdkn1a de células da linhagem C1498. O sobrenadante de CTMs de animais idosos também resultou na maior proliferação e migração de células da linhagem C1498. Portanto, levando em consideração a importância das CTMs sobre a regulação do sistema hematopoético, pode-se concluir que, no envelhecimento, as CTMs criam um ambiente propício para a proliferação celular no qual a manutenção da pluripotência é estimulada, o que pode acarretar em uma desregulação do sítio hematopoético quando habitado por células malignas

Aging is a physiological process in which occurs a series of alterations in an organism that extend to a molecular level. It is a complex process that affects various tissues, one of them being the bone marrow, wherethrough the interactions of the hematopoietic stem cell (CTH) with its surrounding environment, including with the mesenchymal stem cell (CTM), hematopoiesis takes place. Although some aging-associated alterations in the bone marrow can be found described in the literature, the mechanisms behind said changes remain elusive, especially when regarding the cellular interactions present inside the bone marrow. Therefore, this research aimed to investigate how aging affects the regulation of hematopoiesis in the context of its interactions with bone marrow-derived CTMs. For this investigation, male isogenic C57BL/6 mice were used as animal models. These were separated in two groups according to their age: young (3 ­ 5 months) and aged (18 ­ 19 months). The animal models were characterized by their physical properties such as protein intake and weight variation, followed by biochemical and hematological evaluation. Bone marrow cells were obtained and identified through immunophenotyping, thus isolating different cell populations, including the CTMs. To study the relationship between these cells and hematopoiesis, in vitro assays were conducted utilizing the leukemic cell lineage C1498 (TIB-49™, ATCC®) maintained in contact with the supernatant of isolated CTMs. By their biochemical profile, aged mice showed lower levels of albumin, alanine-aspartate transferase (ALT) and triglycerides compared to the young group. In contrast, aged mice had a higher cholesterol level. Hematological evaluation by total blood count showed similar results between the two groups, however, the myelogram revealed that the aged animals had lower cellularity, with less frequent cells from the erythroid lineage, with an increase in granulocytic precursors. Through immunophenotyping, it was also revealed that aged mice have higher numbers of hematopoietic stem cells, while also being noted a reduced population of lymphoid progenitors. An increase in the granulomonocytic progenitors was also found. Immunophenotyping peripheral blood cells of aged mice revealed reduced numbers of B lymphocytes and erythrocytes, and an increased natural killer cell population. Additionally, the cell surface marker CD73 was found to be less expressed in aged mice CTMs. The secretome of these stromal cells obtained from aged mice showed higher levels of CXCL12 and SCF, and lower levels of IL-11when compared to the young counterparts. At a molecular level, CTMs obtained from aged mice expressed more Akt1, Nos and Ppar-γ, while the expression of Csf3 and Cdh2 was reduced. Additionally, when comparing the effects of aged mice CTMs with young mice CTMs, it was observed that the first expressed were capable of increasing the expression of Sox2, Pou5f1 and Nanog, while decreasing Cdkn1a expression in the C1498 cell lineage. The supernatant obtained from aged mice also favored the proliferation and cell migration of the C1498 cell line. Thus, considering the importance that CTMs have over the hematopoietic system, we can conclude that, in aging, CTMs create a special environment which favors cell proliferation and maintenance of pluripotency, which can result in a dysregulation of the hematopoietic tissue when malignant cells are present

Advances in understanding leukemia bone marrow microenvironments / 药学学报

The bone marrow microenvironment, also known as the bone marrow niche, plays a critical role in maintaining the functions of hematopoietic stem cells. Under physiological conditions, various bone marrow cells regulate each other to sustain hematopoietic homeostasis. However, bone marrow cells gain abnormal function under pathological conditions to cause and promote the occurrence of leukemia and induce drug resistance. Recent findings indicate that abnormal proliferation and differentiation are not the sole reason to cause leukemia. Different types of bone marrow cells also induce intercellular adhesion, abnormally secrete cytokines and chemokines, accelerating leukemia's progress. This article reviews the multiple signaling pathways that regulate the formation and progress of leukemia bone marrow niche, such as C-X-C motif chemokine ligand 12/C-X-C motif chemokine receptor 4 signaling pathway, et al. It emphasizes that targeting leukemia bone marrow niche is a vital strategy for improving the leukemia treatment.

Establishment and Validation of Immune Risk Score for Predicting Survival of Patients with Acute Myeloid Leukemia / 中国实验血液学杂志

OBJECTIVE@#To establish an immune gene prognostic model of acute myeloid leukemia (AML) and explore its correlation with immune cells in bone marrow microenvironment.@*METHODS@#Gene expression profile and clinical data of TCGA-AML were downloaded from TCGA database. Immune genes were screened by LASSO analysis to construct prognosis prediction model, and prediction accuracy of the model was quantified by receiver operating characteristic curve and area under the curve. Survival analysis was performed by Log-rank test. Enriched pathways in the different immune risk subtypes were evaluated from train cohort. The relationship between immune prediction model and bone marrow immune microenvironment was verified by flow cytometry in the real world.@*RESULTS@#Patients with low-risk score of immune gene model had better prognosis than those with high-risk score. Multivariate analysis showed that the immune gene risk model was an independent prognostic factor. The risk ratio for AML patients in the training concentration was HR=24.594 (95%CI: 6.180-97.878), and the AUC for 1-year, 3-year, and 5-year overall survival rate was 0.811, 0.815, and 0.837, respectively. In addition, enrichment analysis of differential gene sets indicated activation of immune-related pathways such as cytokines and chemokines as well as autoimmune disease-related pathways. At the same time, real world data showed that patients with high immune risk had lower numbers of CD8+T cells and B lymphocytes compared with low immune risk patients.@*CONCLUSION@#We constructed a stable prognostic model for AML, which can not only predict the prognosis of AML, but also reveal the dysregulation of immune microenvironment.

Research advance in bone marrow metastasis in children′s neuroblastoma / 国际儿科学杂志

Neuroblastoma is the most common extracranial solid tumor for infants and young children.About 50% of patients have extensive metastasis before diagnosis, and the neuroblastoma can metastasize to bone marrow, bone, lymph node, orbit, liver and skin.Bone marrow is the most common site of neuroblastoma metastasis and recurrence.Once neuroblastoma metastasize or relapse, their survival rate will reduce significantly.The mechanism of neuroblastoma bone marrow metastasis has not been elucidated.The drug resistance of tumor cells, the interaction of bone marrow microenvironment, and the regulation of cell signaling pathways may play important roles in regulating tumor cell bone marrow metastasis.This review summarizes the research progress of bone marrow metastasis in neuroblastoma, which helps us to better understand the mechanism of interaction between neuroblastoma and the bone marrow microenvironment, and to provide new ideas for the diagnosis and treatment of patients.

Research advances of mesenchymal stem cells from bone marrow in myelodysplastic syndrome / 基础医学与临床

Myelodysplastic syndrome (MDS) is definded as a group of clonal hematological malignancies characterized by bone marrow (BM) ineffective.hematopoiesis and increases risk for progression to acute myeloid leukemia. The altered BM mesenchymal stem cells (MSCs) play a pivotal role in the evolution and propagation of MDS. Com-pared to normal MSCs, MSCs in MDS often exhibit altered Cytogenetic, epigenetic, differentiation and functional properties, moreover, high MSCs density is associated with poor prognostic factors, which translated into a signifi-cantly diminished ability to support normal hematopoiesis, facilitates survival of malignant hematopoietic cells, ulti-mately promote disease progression and transform to acute myeloid leukemia.Therefore, characterization of key steps in the pathogenesis of MDS will lead to new approaches to treat patients with this disease.

Progress of exosomes in multiple myeloma / 肿瘤研究与临床

Exosomes are small vesicles that are released from multivesicular bodies to the extracellular. They can carry proteins, lipids, DNA, miRNA and mRNA to the recipient cells, thereby altering the biological behavior of the recipient cells. In multiple myeloma (MM), exosomes could regulate the immune system, promote angiogenesis and the transformation of cancer-associated fibroblasts, interact with bone mesenchymal stem cells, enhance osteoclast activity, and induce MM resistance. Exosomes in the blood can be used as an early diagnostic marker for MM in order to provide a new diagnosis and treatment strategy for MM patients. This article summarizes the progress of the function, diagnosis and treatment of exosomes in MM.

Cytokine expression patterns and mesenchymal stem cell karyotypes from the bone marrow microenvironment of patients with myelodysplastic syndromes

The purpose of this study was to explore cytokine expression patterns and cytogenetic abnormalities of mesenchymal stem cells (MSCs) from the bone marrow microenvironment of Chinese patients with myelodysplastic syndromes (MDS). Bone marrow samples were obtained from 30 cases of MDS (MDS group) and 30 healthy donors (control group). The expression pattern of cytokines was detected by customized protein array. The karyotypes of MSCs were analyzed using fluorescence in situ hybridization. Compared with the control group, leukemia inhibitory factor, stem cell factor (SCF), stromal cell-derived factor (SDF-1), bone morphogenetic protein 4, hematopoietic stem cell (HSC) stimulating factor, and transforming growth factor-β in the MDS group were significantly downregulated (P<0.05), while interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), and programmed death ligand (B7-H1) were significantly upregulated (P<0.05). For chromosome abnormality analysis, the detection rate of abnormal karyotypes (+8, -8, -20, 20q-, -Y, -7, 5q-) was 30% in the MDS group and 0% in the control group. In conclusion, the up- and downregulated expression of these cytokines might play a key role in the pathogenesis of MDS. Among them, SCF and SDF-1 may play roles in the apoptosis of HSCs in MDS; and IFN-γ, TNF-α, and B7-H1 may be associated with apoptosis of bone marrow cells in MDS. In addition, the abnormal karyotypes might be actively involved in the pathogenesis of MDS. Further studies are required to determine the role of abnormal karyotypes in the occurrence and development of MDS.

Analysis of Treg in bone marrow of patients with multiple myeloma and its correlation with clinical prog-nostic factors / 实用肿瘤学杂志

Objective To evaluate immune function of patients with multiple myeloma ( MM) by detect the changes of the Treg cells in bone marrow of patients with MM .Methods Treg cells in peripheral blood and bone marrow of 45 patients with MM and 15 healthy controls were measured by flow cytometry .Results The per-centage of Treg cells in peripheral blood of MM was higher than that in healthy person ;The percentage of Treg cells in MM bone marrow was lower than that in healthy person ,and the extent was positively correlated with the level of β2-MG and ISS(P<0.05).Conclusion MM Patients display an abnormal level of CD 4 +CD25 +Treg cells,which may be an important mechanism of MM immune deficiency .

Research progress of hematopoietic stem cells location and its interaction with surrounding microenvironment / 白血病·淋巴瘤

Homing and engraftment of transplanted hematopoietic stem cells (HSCs) can directly influence the effect of the transplantation.Exploration on its spatial distribution,location and interaction with the bone marrow (BM) microenvironment is great significance.Since the BM cavity is closed and surrounded by thick compact bone,it makes a colossal challenge to track the transplanted HSCs in vivo directly.Recently,researchers used different innovative methods to observe the spatial distribution and interaction with the BM microenvironment of the transplanted HSCs.The present review summarized the progress in the HSCs transplantation.

Effect of salidroside on radiation-induced bone marrow adipogenesis / 中华放射医学与防护杂志

Objective To investigate the potential and underlying molecular mechanism of salidroside in ameliorating radiation-induced bone marrow adipogenesis and stimulating hematopoiesis.Methods The female BALB/c mice aged 6-7 weeks were randomly divided into normal control group,radiation group and salidroside group.The radiation group and salidroside group were irradiated with 6.0 Gy of 60Co γ-rays.The salidroside group was intraperitoneally injected with 30 mg· kg-1 · d-1 salidroside at 12 h and then every day until 8th d after radiation.The normal control group and radiation group were treated with equal volume of saline as control of salidroside.At 14 d after radiation,the mice weight,peripheral blood count,femur bone marrow histology,and the proportion of adipocyte area were measured,and the expressions of PPAR-γ and FABP4 were detected by q-PCR.Results After irradiation,the numbers of white blood cells,hemoglobin and platelet in peripheral blood were reduced obviously,and the percentage of adipocyte area was increased significantly.Compared with mice in the radiation group,salidroside inhibited adipogenesis and reduced the proportion of adipocyte area (t =13.31,P ＜ 0.05) by reducing the expressions of PPAR-γ and FABP4 (t =8.64,13.19,P ＜ 0.05).The number of white blood cells was partly recovered at 7 d after irradiation (t =5.80,P ＜ 0.05).Both white blood cells and hemoglobinin in peripheral blood of the salidroside group were higher than those in the radiation group at 14 d after irradiation.Conclusions Salidroside could inhibit radiation-induced bone marrow adipogenesis and regulate bone marrow microenvironment,thereby promotes hematopoietic recovery in mice after radiation injury.

Protective effect of 1,25-(OH)2D3 on radiation-induced bone marrow microenvironment injury / 中华放射医学与防护杂志

Objective To investigate the protective effect of 1,25-(OH) 2D3 on radiation-induced bone marrow microenvironment injury and to explore the related molecular mechanism.Methods Sixty 7-week old male BALB/c mice were randomly divided into control group without any treatment; radiation group exposed to 6.0 Gy 60Co γ-rays with DMSO,and 1,25-(OH)2 D3 + radiation group treated with 1,25-(OH)2D32.5 μg/kg dissolved in DMSO each day and 6 Gy of γ-rays.The body weight and peripheral white blood cells,femur bone marrow histology,and the proportion of adipocyte area were measured.The expression of peroxisome proliferator-activated receptor-gamma (PPARγ) was detected immunohistochemistrically at 8 d after irradiation.Results After irradiation,the number of white blood cells and the body weight decreased obviously,and the percentage of adipocyte area was increased significantly.Compared with radiation group,1,25-(OH)2D3 reduced the decrease rate of body weight (t =-2.23,-2.34,P ＜ 0.05),partly recovered the number of white blood cells at 4 or 8 d after irradiation(t =-4.99,-4.46,P ＜ 0.05),and reduced the proportion of adipocyte area (t =-3.75,-2.10,P ＜ 0.05).With immunohistochemistrical assay,it was found that 1,25-(OH) 2D3 inhibited adipogenesis by reducing the expression of PPARγ.Conclusions 1,25-(OH) 2 D3 decreases radiationinduced adipogenesis and hence protects the bone marrow microenvironment from radiation damage.

In Osteoporosis, differentiation of mesenchymal stem cells (MSCs) improves bone marrow adipogenesis

The formation, maintenance, and repair of bone tissue involve close interlinks between two stem cell types housed in the bone marrow: the hematologic stem cell originating osteoclasts and mesenchymal stromal cells (MSCs) generating osteoblasts. In this review, we consider malfunctioning of MSCs as essential for osteoporosis. In osteoporosis, increased bone fragility and susceptibility to fractures result from increased osteoclastogenesis and insufficient osteoblastogenesis. MSCs are the common precursors for both osteoblasts and adipocytes, among other cell types. MSCs' commitment towards either the osteoblast or adipocyte lineages depends on suitable regulatory factors activating lineage-specific transcriptional regulators. In osteoporosis, the reciprocal balance between the two differentiation pathways is altered, facilitating adipose accretion in bone marrow at the expense of osteoblast formation; suggesting that under this condition MSCs activity and their microenvironment may be disturbed. We summarize research on the properties of MSCs isolated from the bone marrow of control and osteoporotic post-menopausal women. Our observations indicate that intrinsic properties of MSCs are disturbed in osteoporosis. Moreover, we found that the regulatory conditions in the bone marrow fluid of control and osteoporotic patients are significantly different. These conclusions should be relevant for the use of MSCs in therapeutic applications.

Expressions of IL-1?,IL-6,SCF,TPO on bone marrow stromal cells in patients with multiple myelo-ma / 肿瘤研究与临床

Objective To study multiple cytokine mRNA expressions of bone marrow stromal cells in patients with multiple myeloma(MM),as well as to explore the role of these cytokines in the occurrence and development of MM.Methods Semi-quantitiative RT-PCR was used to detect the mRNA expressions of IL- 1?,IL-6,SCF,TPO.Results The mRNA expression levels of IL-1? and IL-6 were higher than that of nor- mal controls and other hematological malignancies(P

In vitro protection of Jurkat cells from daunorubicin induced apoptosis by normal bone marrow stromal cells / 中国输血杂志

Objective To study the influence of bone marrow microenvironment on leukemic cells during chemotherapy and the influence on leukemic cells' drug-resistance and anti-apoptosis. Methods Normal bone marrow stromal cells were isolated using Percoll, and then were cocultured with human acute lymphocyte leukemic cell line Jurkat cells in vitro. Apoptosis percentage of Jurkat cells labelled with Annexin V/PI were detected by FCM. Results Apoptosis percentage of Jurkat cells cocultured with bone marrow stromal cells for 24 hours was lower than those maintained in suspension (P