Objective To investigate the effects of miR-181b-5p on cells proliferation and apoptosis in acute myeloid leukemia (AML) by targeting paired box 9 (PAX9). Methods The relationship between expression level of PAX9 and prognosis in AML patients was analyzed by gene expression profiling interactive analysis (GEPIA) database and The Cancer Genome Atlas (TCGA) database. Kasumi-1 and AML5 cells were transfected with empty vector (Vector group) or PAX9 (PAX9 group). The proliferation activity was detected by CCK-8 assay, and cells cycle and apoptosis were detected by flow cytometry. Expressions of cyclin-dependent kinase 2 (CDK2), cyclin B1 (CCNB1), B-cell lymphoma 2 (Bcl2) and Bcl2-associated X protein (BAX) were detected by Western blot analysis. The targeted microRNA (miRNA) by PAX9 was predicted by bioinformatics analysis, and the targeted effect was verified by luciferase reporter assay. The level of PAX9 mRNA was detected by real-time quantitative PCR, and expression of PAX9 protein was detected by Western blot analysis. Kasumi-1 and AML5 cells were transfected with miR-NC (miR-NC group) or miR-181b-5p (miR-181b-5p group). The cells were further transfected with PAX9 (miR-181b-5p combined with PAX9 group) in miR-181b-5p group. The proliferation, cycle and apoptosis of cells were detected by the above methods.Results GEPIA and TCGA databases showed that the expression of PAX9 was down-regulated in AML patients, which was correlated with poor prognosis. In Kasumi-1 and AML5 cells, compared with Vector group, proliferation activity of cells, percentage of cells in S phase, and expressions of CDK2, CCNB1 and Bcl2 proteins were decreased, while percentage of cells in G0/G1 phase, apoptosis rate and the expression of BAX protein were increased in PAX9 group. It was confirmed by double luciferase reporter assay that PAX9 was the target gene of miR-181b-5p. Compared with miR-NC group, proliferation activity of cells, percentage of cells in S phase, and expressions of CDK2, CCNB1 and Bcl2 proteins were increased, while percentage of cells in G0/G1 phase, apoptosis rate and the expression of BAX protein were decreased in miR-181b-5p group. Compared with miR-181b-5p group, proliferation activity of cells, percentage of cells in S phase, and expressions of CDK2, CCNB1 and Bcl2 proteins were decreased, while percentage of cells in G0/G1 phase, apoptosis rate and the expression of BAX protein were increased in miR-181b-5p combined with PAX9 group. Conclusion The miR-181b-5p can promote the proliferation of AML cells and delay apoptosis by inhibiting PAX9.
Humans ; Apoptosis/genetics* ; bcl-2-Associated X Protein ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Leukemia, Myeloid, Acute/pathology* ; Luciferases ; MicroRNAs/metabolism* ; PAX9 Transcription Factor/genetics*

OBJECTIVE: To investigate the effects of long non-coding RNA (lncRNA) GATA3 antisense RNA 1 (GATA3-AS1) targeting miR-515-5p on the proliferation and apoptosis of childhood acute lymphoblastic leukemia (ALL) cells. METHODS: RT-qPCR was used to determine the expression of GATA3-AS1 and miR-515-5p in the plasma of controls and ALL children. Human ALL cells Jurkat were divided into si-GATA3-AS1, si-NC, miR-NC, miR-515-5p, si-GATA3-AS1+anti-miR-NC and si-GATA3-AS1+anti-miR-515-5p groups. CCK-8 assay was used to detect the cell proliferation, and flow cytometry was used to detect the cell apoptosis. The targeting relationship between GATA3-AS1 and miR-515-5p was determined by dual-luciferase reporter assay. RESULTS: The expression level of GATA3-AS1 in the plasma of ALL children was significantly higher than that of controls (P <0.001), while the expression level of miR-515-5p was significantly lower than that of controls (P <0.001). Compared with the si-NC group, the cell inhibition rate, apoptosis rate, and miR-515-5p expression level in si-GATA3-AS1 group were significantly increased (P <0.001). Compared with the miR-NC group, the cell inhibition rate and apoptosis rate in miR-515-5p group were significantly increased (P <0.001). GATA3-AS1 could directly and specifically bind to miR-515-5p. Compared with the si-GATA3-AS1+anti-miR-NC group, the cell inhibition rate and apoptosis rate in si-GATA3-AS1+anti-miR-515-5p group were significantly decreased (P <0.001). CONCLUSION Down-regulation of GATA3-AS1 can inhibit proliferation and induce apoptosis of childhood ALL cells by targeting up-regulation of miR-515-5p expression.
Child ; Humans ; MicroRNAs/metabolism* ; RNA, Long Noncoding/metabolism* ; Antagomirs/pharmacology* ; Cell Line, Tumor ; Cell Proliferation ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Apoptosis ; Gene Expression Regulation, Neoplastic ; GATA3 Transcription Factor/metabolism*

OBJECTIVE: To investigate the effects of methionine restriction on proliferation, cell cycle and apoptosis of human acute leukemia cells. METHODS: Cell Counting Kit-8 (CCK-8) assay was used to detect the effect of methionine restriction on HL-60 and Jurkat cells proliferation. The effect of methionine restriction on cell cycle of HL-60 and Jurkat cells was examined by PI staining. Annexin V-FITC / PI double staining was applied to detect apoptosis of HL-60 and Jurkat cells following methionine restriction. The expression of cell cycle-related proteins cyclin B1, CDC2 and apoptosis-related protein Bcl-2 was evaluated by Western blot assay. RESULTS: Methionine restriction significantly inhibited the proliferation of HL-60 and Jurkat cells in a time-dependent manner (HL-60: r =0.7773, Jurkat: r =0.8725), arrested the cells at G2/M phase (P < 0.001), and significantly induced apoptosis of HL-60 and Jurkat cells (HL-60: P < 0.001; Jurkat: P < 0.05). Furthermore, Western blot analysis demonstrated that methionine restriction significantly reduced the proteins expression of Cyclin B1 (P < 0.05), CDC2 (P < 0.01) and Bcl-2 (P < 0.001) in HL-60 and Jurkat cells. CONCLUSION Acute leukemia cells HL-60 and Jurkat exhibit methionine dependence. Methionine restriction can significantly inhibit the proliferation, promote cell cycle arrest and induce apoptosis of HL-60 and Jurkat cells, which suggests that methionine restriction may be a potential therapeutic strategy for acute leukemia.
Humans ; Cyclin B1/pharmacology* ; Cell Proliferation ; Methionine/pharmacology* ; Cell Cycle ; Apoptosis ; Leukemia, Myeloid, Acute ; Cell Division ; Cell Cycle Proteins ; Jurkat Cells ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; HL-60 Cells

OBJECTIVE: To investigate the effect of phorbol-12-myristate-13-ace-tate (TPA) on the proliferation and apoptosis of acute promyelocytic leukemia cell line NB4 and its molecular mechanism. METHODS: The effect of different concentrations of TPA on the proliferation of NB4 cells at different time points was detected by CCK-8 assay. The morphological changes of NB4 cells were observed by Wright-Giemsa staining. The cell cycle and apoptosis of NB4 cells after TPA treatment were detected by flow cytometry. The mRNA expressions of NB4 cells after TPA treatment were analyzed by high-throughput microarray analysis and real-time quantitative PCR. Western blot was used to detect the protein expression of CDKN1A, CDKN1B, CCND1, MYC, Bax, Bcl-2, c-Caspase 3, c-Caspase 9, PIK3R6, AKT and p-AKT. RESULTS: Compared with the control group, TPA could inhibit the proliferation of NB4 cells, induce the cells to become mature granulocyte-monocyte differentiation, and also induce cell G₁ phase arrest and apoptosis. Differentially expressed mRNAs were significantly enriched in PI3K/AKT pathway. TPA treatment could increase the mRNA levels of CCND1, CCNA1, and CDKN1A, while decrease the mRNA level of MYC. It could also up-regulate the protein levels of CDKN1A, CDKN1B, CCND1, Bax, c-Caspase 3, c-Caspase 9, and PIK3R6, while down-regulate MYC, Bcl-2, and p-AKT in NB4 cells. CONCLUSION TPA induces NB4 cell cycle arrest in G₁ phase and promotes its apoptosis by regulating PIK3/AKT signaling pathway.
Humans ; Leukemia, Promyelocytic, Acute ; Caspase 3/metabolism* ; Caspase 9/pharmacology* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Cell Line, Tumor ; Cell Division ; Apoptosis ; RNA, Messenger ; Cell Proliferation

OBJECTIVE: To explore the effect of cytokine levels on early death and coagulation function of patients with newly diagnosed acute promyelocytic leukemia (APL). METHODS: Routine examination was performed on 69 newly diagnosed APL patients at admission. Meanwhile, 4 ml fasting venous blood was extracted from the patients. And then the supernatant was taken after centrifugation. The concentrations of cytokines, lactate dehydrogenase (LDH) and ferritin were detected by using the corresponding kits. RESULTS: It was confirmed that cerebral hemorrhage was a major cause of early death in APL patients. Elevated LDH, decreased platelets (PLT) count and prolonged prothrombin time (PT) were high risk factors for early death (P <0.05). The increases of IL-5, IL-6, IL-10, IL-12p70 and IL-17A were closely related to the early death of newly diagnosed APL patients, and the increases of IL-5 and IL-17A also induced coagulation disorder in APL patients by prolonging PT (P <0.05). In newly diagnosed APL patients, ferritin and LDH showed a positive effect on the expression of IL-5, IL-10 and IL-17A, especially ferritin had a highly positive correlation with IL-5 (r =0.867) and IL-17A (r =0.841). Moreover, there was a certain correlation between these five high-risk cytokines, among which IL-5 and IL-17A (r =0.827), IL-6 and IL-10 (r =0.823) were highly positively correlated. CONCLUSION Elevated cytokine levels in newly diagnosed APL patients increase the risk of early bleeding and death. In addition to the interaction between cytokines themselves, ferritin and LDH positively affect the expression of cytokines, thus affecting the prognosis of APL patients.
Humans ; Leukemia, Promyelocytic, Acute/diagnosis* ; Cytokines/metabolism* ; Interleukin-10 ; Interleukin-17/metabolism* ; Interleukin-6/metabolism* ; Interleukin-5/metabolism* ; Blood Coagulation Disorders ; Ferritins ; Tretinoin

OBJECTIVE: To investigate the effect of long non-coding RNA LINC01268 on apoptosis of acute myeloid leukemia (AML) cells and related mechanisms. METHODS: The expression levels of LINC01268 and miR-217 in peripheral blood samples from AML patients and AML cell lines HL-60 and KG-1 were detected by qRT-PCR. HL-60 cells were divided into pcDNA3.1-NC, pcDNA3.1-LINC01268, si-NC, si-LINC01268, miR-NC, miR-217 mimics, si-LINC01268 + inhibitor-NC and si-LINC01268+ miR-217 inhibitor groups. The mRNA expressions of LINC01268 and miR-217 were detected by qRT-PCR. The targeting relationship between LINC01268 and miR-217 was detected by dual-luciferase reporter assay. Cell viability was detected by CCK-8 assay. Cell cycle distribution and apoptosis were detected by flow cytometry. The expression of cell cycle and apoptosis-related proteins p21, Bcl-2, Bax, caspase-3 and PI3K/AKT signaling pathway-related proteins were detected by Western blot. RESULTS: The expression of LINC01268 in peripheral blood samples of AML patients and AML cell lines HL-60 and KG-1 was increased (P < 0.05), and the expression of miR-217 was decreased (P < 0.05). Compared with si-NC group and miR-NC group, the viability of HL-60 cells was decreased in si-LINC01268 group and miR-217 mimics group (P < 0.05), the proportion of cells in G₁ phase and apoptosis rate were increased (P < 0.05), the protein expression levels of p21, Bax and caspase-3 were increased (P < 0.05), while the protein expression level of Bcl-2 was decreased (P < 0.05). LINC01268 targeted and negatively regulated the expression of miR-217, and inhibiting the expression of miR-217 partially reversed the effects of LINC01268 interference on the viability, cell cycle and apoptosis of HL-60 cells. Interference with LINC01268 could inhibit the activity of PI3K/AKT signaling pathway. Inhibiting the expression of miR-217 could partially reverse the inhibition of LINC01268 interference on PI3K/AKT signaling pathway. CONCLUSION LINC01268 is highly expressed and miR-217 is lowly expressed in AML cells. LINC01268 can promote the activity of PI3K/AKT signaling pathway, increase the survival rate and inhibit the apoptosis of AML cells by targeting miR-217 expression.
Humans ; Apoptosis ; bcl-2-Associated X Protein/metabolism* ; Caspase 3 ; Cell Line, Tumor ; Cell Proliferation ; Leukemia, Myeloid, Acute/metabolism* ; MicroRNAs/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; RNA, Long Noncoding/genetics*

OBJECTIVE: To investigate the effect of miR-22 targeting formin-like protein 2 (FMNL2) on the migration and apoptosis of childhood acute myeloid leukemia (AML) cells. METHOD: Peripheral blood samples from 11 children with AML, 10 children with immune thrombocytopenia, human AML cell lines TF-1a, HL-60, THP-1 and human bone marrow stromal cells HS-5 were used as the research objects. UniCel DxH 800 automatic hematology analyzer detected platelet count, hemoglobin, and white blood cell count in peripheral blood samples, and RT-qPCR detected miR-22 expression in peripheral blood samples and AML cells. HL-60 cells were transfected with Lipofectamine^TM 2000 kit, the experiments were divided into seven groups: blank (no cells transfected), miR-NC, miR-22 mimics, si-NC, si-FMNL2 , miR-22 mimics+OE-NC and miR-22 mimics+OE-FMNL2 . RT-qPCR was used to detect the expression of miR-22 in each group. Transwell was used to detect cell migration. Flow cytometry was used to detect cell apoptosis. Dual-luciferase reporter gene detection experiments verified the targeting relationship between miR-22 and FMNL2 . Western blot was used to detect the expression of FMNL2 protein. RESULTS: Compared with the control group, the number of leukocytes in the peripheral blood of children with AML was significantly increased (P <0.001), while the concentration of hemoglobin and the number of platelets were significantly decreased P <0.001). The expression level of miR-22 in peripheral blood of children with AML was significantly lower than that in control group (P <0.001). Compared with HS-5 cells, the expression levels of miR-22 in TF-1a, HL-60, and THP-1 cells were significantly decreased (P <0.05), and in HL-60 cells was the lowest. Therefore, HL-60 cells were selected for subsequent experiments. Up-regulation of miR-22 or silencing of FMNL2 could reduce the number of migrating cells and increase apoptosis rate (P <0.05). MiR-22 targeted and negatively regulated the expression of FMNL2 . FMNL2 overexpression reversed the effects of up-regulated miR-22 on migration and apoptosis of HL-60 cells. CONCLUSION MiR-22 can inhibit the migration and promote apoptosis of HL-60 cells by down regulating the expression of FMNL2 .
Humans ; Child ; MicroRNAs/metabolism* ; Leukemia, Myeloid, Acute/metabolism* ; Cell Proliferation ; Apoptosis ; Myeloproliferative Disorders ; Cell Movement ; Hemoglobins ; Cell Line, Tumor ; Formins

Mesenchymal stem cell (MSC)-based therapy has emerged as a promising treatment for spinal cord injury (SCI), but improving the neurogenic potential of MSCs remains a challenge. Mixed lineage leukemia 1 (MLL1), an H3K4me3 methyltransferases, plays a critical role in regulating lineage-specific gene expression and influences neurogenesis. In this study, we investigated the role and mechanism of MLL1 in the neurogenesis of stem cells from apical papilla (SCAPs). We examined the expression of neural markers, and the nerve repair and regeneration ability of SCAPs using dynamic changes in neuron-like cells, immunofluorescence staining, and a SCI model. We employed a coimmunoprecipitation (Co-IP) assay, real-time RT-PCR, microarray analysis, and chromatin immunoprecipitation (ChIP) assay to investigate the molecular mechanism. The results showed that MLL1 knock-down increased the expression of neural markers, including neurogenic differentiation factor (NeuroD), neural cell adhesion molecule (NCAM), tyrosine hydroxylase (TH), βIII-tubulin and Nestin, and promoted neuron-like cell formation in SCAPs. In vivo, a transplantation experiment showed that depletion of MLL 1 in SCAPs can restore motor function in a rat SCI model. MLL1 can combine with WD repeat domain 5 (WDR5) and WDR5 inhibit the expression of neural markers in SCAPs. MLL1 regulates Hairy and enhancer of split 1 (HES1) expression by directly binds to HES1 promoters via regulating H3K4me3 methylation by interacting with WDR5. Additionally, HES1 enhances the expression of neural markers in SCAPs. Our findings demonstrate that MLL1 inhibits the neurogenic potential of SCAPs by interacting with WDR5 and repressing HES1. These results provide a potential therapeutic target for promoting the recovery of motor function in SCI patients.
Animals ; Humans ; Rats ; Cell Differentiation ; Intracellular Signaling Peptides and Proteins/therapeutic use* ; Leukemia/metabolism* ; Mesenchymal Stem Cells ; Neurogenesis ; Stem Cells ; Transcription Factor HES-1/metabolism*

Acyl-CoA synthetase long chain family member 5 (ACSL5), is a member of the acyl-CoA synthetases (ACSs) family that activates long chain fatty acids by catalyzing the synthesis of fatty acyl-CoAs. The dysregulation of ACSL5 has been reported in some cancers, such as glioma and colon cancers. However, little is known about the role of ACSL5 in acute myeloid leukemia (AML). We found that the expression of ACSL5 was higher in bone marrow cells from AML patients compared with that from healthy donors. ACSL5 level could serve as an independent prognostic predictor of the overall survival of AML patients. In AML cells, the ACSL5 knockdown inhibited cell growth both in vitro and in vivo. Mechanistically, the knockdown of ACSL5 suppressed the activation of the Wnt/β-catenin pathway by suppressing the palmitoylation modification of Wnt3a. Additionally, triacsin c, a pan-ACS family inhibitor, inhibited cell growth and robustly induced cell apoptosis when combined with ABT-199, the FDA approved BCL-2 inhibitor for AML therapy. Our results indicate that ACSL5 is a potential prognosis marker for AML and a promising pharmacological target for the treatment of molecularly stratified AML.
Humans ; Antineoplastic Agents/therapeutic use* ; Apoptosis ; beta Catenin/metabolism* ; Biomarkers, Tumor/metabolism* ; Cell Line, Tumor ; Coenzyme A Ligases/metabolism* ; Leukemia, Myeloid, Acute/metabolism* ; Lipoylation ; Prognosis ; Wnt Signaling Pathway

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*