Multiple myeloma (MM) is a malignant proliferative disease of plasma cells. Bone marrow mesenchymal stem cells (MSC) play an important role in the progression of MM. Compared with normal donor derived MSC (ND-MSC), MM patients derived MSC (MM-MSC) exhibit abnormalities in genes, signaling pathways, protein expression levels and cytokines secreted by themselves. Moreover, the exosomes of MM-MSC can interact with the bone marrow microenvironment. The above reasons can lead to MM cell proliferation, chemoresistance, impaired osteogenic differentiation of MM-MSC, and affect the immunomodulatory capacity of MM patients. In order to further understand the pathogenesis and related influencing factors of MM, this paper reviews the latest research progress of MM-MSC.
Humans ; Multiple Myeloma/pathology* ; Osteogenesis ; Mesenchymal Stem Cells ; Cell Differentiation ; Bone Marrow/metabolism* ; Bone Marrow Cells/metabolism* ; Tumor Microenvironment

BACKGROUND: Imatinib mesylate (IM) resistance is an emerging problem for chronic myeloid leukemia (CML). Previous studies found that connexin 43 (Cx43) deficiency in the hematopoietic microenvironment (HM) protects minimal residual disease (MRD), but the mechanism remains unknown. METHODS: Immunohistochemistry assays were employed to compare the expression of Cx43 and hypoxia-inducible factor 1α (HIF-1α) in bone marrow (BM) biopsies of CML patients and healthy donors. A coculture system of K562 cells and several Cx43-modified bone marrow stromal cells (BMSCs) was established under IM treatment. Proliferation, cell cycle, apoptosis, and other indicators of K562 cells in different groups were detected to investigate the function and possible mechanism of Cx43. We assessed the Ca 2+ -related pathway by Western blotting. Tumor-bearing models were also established to validate the causal role of Cx43 in reversing IM resistance. RESULTS: Low levels of Cx43 in BMs were observed in CML patients, and Cx43 expression was negatively correlated with HIF-1α. We also observed that K562 cells cocultured with BMSCs transfected with adenovirus-short hairpin RNA of Cx43 (BMSCs-shCx43) had a lower apoptosis rate and that their cell cycle was blocked in G0/G1 phase, while the result was the opposite in the Cx43-overexpression setting. Cx43 mediates gap junction intercellular communication (GJIC) through direct contact, and Ca 2+ is the key factor mediating the downstream apoptotic pathway. In animal experiments, mice bearing K562, and BMSCs-Cx43 had the smallest tumor volume and spleen, which was consistent with the in vitro experiments. CONCLUSIONS Cx43 deficiency exists in CML patients, promoting the generation of MRD and inducing drug resistance. Enhancing Cx43 expression and GJIC function in the HM may be a novel strategy to reverse drug resistance and promote IM efficacy.
Animals ; Humans ; Mice ; Apoptosis ; Bone Marrow Cells ; Cell Communication ; Connexin 43/genetics* ; Gap Junctions/metabolism* ; Imatinib Mesylate/therapeutic use* ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology* ; Mesenchymal Stem Cells/metabolism* ; Tumor Microenvironment ; Calcium/metabolism*

Multiple myeloma (MM) is a common hematologic tumor characterized by malignant proliferation of clonal plasma cells, the exact pathogenesis of which is not yet fully understood. The extracellular vesicles (EV) are structures released by cells into their surroundings that do not have a functional nucleus and can communicate between cells or deliver biologically active proteins and nucleic acids to target cells. EV play an important role in the interaction between myeloma cells and the bone marrow microenvironment, and they can promote MM progression. In this paper, we summarize the recent research progress in the mechanism of action of EV on MM in order to provide inspiration for exploring new strategies for MM treatment and prognostic stratification.
Bone Marrow/metabolism* ; Extracellular Vesicles/pathology* ; Hematologic Neoplasms/metabolism* ; Humans ; Multiple Myeloma/pathology* ; Nucleic Acids/metabolism* ; Tumor Microenvironment

No abstract available.
Bone Marrow/pathology ; Chromosomes, Human, Pair 12 ; Chromosomes, Human, Pair 9 ; Core Binding Factor Alpha 2 Subunit/*genetics ; DNA/metabolism ; Gene Rearrangement ; Humans ; In Situ Hybridization, Fluorescence ; Karyotyping ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis/*genetics ; Male ; Middle Aged ; Oncogene Proteins, Fusion/*genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Translocation, Genetic

No abstract available.
Aged, 80 and over ; Base Sequence ; Bone Marrow/pathology ; DNA/chemistry/metabolism ; Female ; Fusion Proteins, bcr-abl/*genetics ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/diagnosis/*genetics ; Multiplex Polymerase Chain Reaction ; Protein Isoforms/genetics ; Sequence Analysis, DNA

OBJECTIVETo investigate the IL-32 mRNA expression of bone marrow stromal cells and its correlation with apoptosis of bone marrow mononuclear cells in patients with myelodysplastic syndrome (MDS).

METHODSBone marrow samples from 26 MDS patients and 10 iron deficiency anemia (IDA, as control) patients were collected, RT-PCR was used to detect the IL-32 mRNA expression of bone marrow stromal cells, and the apoptosis of bone marrow mononuclear cells was detected by flow cytometry with Annexin V-FITC/PI dowble staining. The born marrow lymphocytes and NK cells were detected by means of direct immunofluorescence labeling whole blood hemolysis and flow cytometry.

RESULTSIL-32 mRNA expression of bone marrow stromal cells in the MDS patients was significantly higher than that of control group, the IL-32 mRNA expression of bone marrow stromal cells in patients with RA, RAS and RCMD was significantly higher than that in patients with RAEB. There was no obvious difference between RAEB and the control groups. The apoptosis of bone marrow mononuclear cells in MDS group was significantly higher than that in the control group, the apoptosis of bone marrow mononuclear cells in patients with RA, RAS and RCMD was significantly higher than that in RAEB. There was no significant difference between RAEB group and control group. The IL-32 mRNA expression in bone marrow stromal cells significantly correlated with the apoptosis of bone marrow mononuclear cells in MDS patients. The NK cell number in born marrow of MDS patients and the control group had no significant difference.

CONCLUSIONThe expression of IL-32 mRNA in bone marrow stromal cells significantly relates with the apoptosis of MDS cells, and the secretion of IL-32 by bone marrow stromal cells may be one of the reasons for the apoptosis of MDS bone marrow cells. It is speculated that the abnormal MDS bone marrow microenvironment is involved in the apoptosis of bone marrow cells.

Apoptosis ; Bone Marrow Cells ; metabolism ; Flow Cytometry ; Humans ; Interleukins ; metabolism ; Mesenchymal Stromal Cells ; metabolism ; Myelodysplastic Syndromes ; pathology ; RNA, Messenger ; metabolism

OBJECTIVETo investigate the role of Rheb (mTOR activator) in AML development by measuring Rheb expression in bone marrow of adult AML patients and in AML cell line HL-60.

METHODSReal-time PCR assay was used to measure the Rheb mRNA expression in 27 AML patients and 29 ITP patients as control. The relationship between Rheb mRNA expression and age, AML subtype, fusion gene, splenomegaly, hepatomegaly and survival of AML patients was analyzed and compared. In addition, HL-60 cell line over-expressing Rheb was established, and the HL-60 cells and HL-60 cells with overexpression of Rheb were treated with Ara-C of different concentrations, the proliferation level was detected by CCK-8 method, and the IC50 was calculated.

RESULTSThe mRNA level of Rheb in AML patients was similar to that in ITP patients (control). Interestingly, higher expression of Rheb was associated with better survival and was sensitive to Ara-C treatment. However, the expression level of Rheb was not associated with age, AML subtype, fusion gene, and hepatomegaly of patients. Lower expression level of Rheb was associated with splenomegaly. In vitro analysis of HL-60 line indicated that overexpression of Rheb could increased the cell sensitivity to Ara-C treatment (IC50=0.54 µmol/L) and caused HL-60 cell apoptosis.

CONCLUSIONThe lower Rheb expression is a poor prognostic indicator for AML patients, which is associated with AML splenomegaly, the patients and HL-60 cells with low expression of Rheb are insensitive to Ara-C treatment.

Adult ; Apoptosis ; Bone Marrow ; metabolism ; Cytarabine ; pharmacology ; HL-60 Cells ; Humans ; Leukemia, Myeloid, Acute ; genetics ; metabolism ; pathology ; Monomeric GTP-Binding Proteins ; genetics ; metabolism ; Neuropeptides ; genetics ; metabolism ; RNA, Messenger ; genetics ; metabolism ; Ras Homolog Enriched in Brain Protein ; Real-Time Polymerase Chain Reaction ; Spleen ; pathology

No abstract available.
Adolescent ; Anemia, Aplastic/*diagnosis/pathology ; Bone Marrow/pathology ; Child ; Child, Preschool ; Diagnosis, Differential ; Female ; Half-Life ; Humans ; Immunohistochemistry ; Male ; Mutation ; Myelodysplastic Syndromes/*diagnosis/pathology ; Retrospective Studies ; Tumor Suppressor Protein p53/genetics/*metabolism

We report the first Far Eastern case of a Korean child with familial hemophagocytic lymphohistiocytosis (HLH) caused by a novel syntaxin 11 (STX11) mutation. A 33-month-old boy born to non-consanguineous Korean parents was admitted for intermittent fever lasting one week, pancytopenia, hepatosplenomegaly, and HLH in the bone marrow. Under the impression of HLH, genetic study revealed a novel homozygous missense mutation of STX11: c.650T>C, p.Leu217Pro. Although no large deletion or allele drop was identified, genotype analysis demonstrated that the homozygous c.650T>C may have resulted from the duplication of a maternal (unimaternal) chromosomal region and concurrent loss of the other paternal allele, likely caused by meiotic errors such as two crossover events. A cumulative study of such novel mutations and their effects on specific protein interactions may deepen the understanding of how abnormal STX1 expression results in deficient cytotoxic function.
Alleles ; Amino Acid Sequence ; Asian Continental Ancestry Group/*genetics ; Base Sequence ; Bone Marrow/metabolism ; Child, Preschool ; Comparative Genomic Hybridization ; DNA Mutational Analysis ; Genotype ; Haplotypes ; Homozygote ; Humans ; Lymphohistiocytosis, Hemophagocytic/*genetics/pathology ; Male ; Molecular Sequence Data ; Mutation, Missense ; Pedigree ; Qa-SNARE Proteins/*genetics ; Republic of Korea ; Sequence Alignment

OBJECTIVETo observe the effects of Compound Zhebei Granule (, CZBG) combined with chemotherapy on surface markers of leukemia stem cell (LSC) in the bone marrow of patients with acute myeloid leukemia (AML).

METHODSSeventy-eight patients with AML received bone marrow aspiration and the percentages of CD34(+) CD123(+) and CD33(+) CD123(+) cells were tested using flow cytometry method. A total of 24 refractory or relapsed AML patients were enrolled and treated with one cycle of standard chemotherapy combined with CZBG. Bone marrow samples were obtained before and after treatment, and the percentages of CD34(+) CD123(+) and CD33(+) CD123(+) cells were examined by flflow cytometry.

RESULTSCompared with refractory or relapsed AML patients, patients achieved remission had a significant lower percentage of CD34(+) CD123(+) cells(P<0.01) and CD33(+) CD123(+) cells (P<0.01), indicating that controlling the LSC percentage may be important for patients with AML to achieve sustainable remission. Compared with those before treatment, the expression levels of CD34(+) CD123(+) were significantly decreased after CZBG combined with chemotherapy treatment (P<0.01). The percentages of CD34(+) CD123(+) cells and CD33(+) CD123(+) in patients achieving complete remission after CZBG combined with chemotherapy treatment were both significantly lower than those in patients with nonremission (P<0.01).

CONCLUSIONCZBG combining chemotherapy could reduce the percentages of CD34(+) CD123(+) and CD33(+) CD123(+) LSC, which might improve the clinical efficacy of refractory or relapsed AML.

Antigens, CD ; metabolism ; Antineoplastic Agents ; therapeutic use ; Antineoplastic Combined Chemotherapy Protocols ; therapeutic use ; Biomarkers, Tumor ; metabolism ; Bone Marrow Cells ; drug effects ; metabolism ; pathology ; Drugs, Chinese Herbal ; therapeutic use ; Female ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; pathology ; Male ; Middle Aged ; Neoplastic Stem Cells ; metabolism ; pathology ; Remission Induction