Objective Acute myeloid leukemia(AML)is an aggressive hematological malignancy characterized by abnormal myeloid blast expansion.Recent studies have demonstrated that circular RNAs play a role in AML pathogenesis.In t...Objective Acute myeloid leukemia(AML)is an aggressive hematological malignancy characterized by abnormal myeloid blast expansion.Recent studies have demonstrated that circular RNAs play a role in AML pathogenesis.In this study,we aimed to investigate the clinical significance of circ_0012152 in AML and elucidate its underlying molecular mechanism in the pathogenesis of this condition.Methods Circ_0012152 expression was detected by quantitative real-time polymerase chain reaction in samples obtained from 247 patients with AML and 40 healthy controls.A systematic analysis of clinical characteristics and prognostic factors was also conducted.Cell growth was assessed using the Cell Counting Kit-8(CCK-8)assay,and apoptosis and cell cycle progression were evaluated by flow cytometry.Moreover,RNA pull-down was performed to identify target microRNAs,and transcriptome RNA sequencing and bioinformatics analyses were utilized to identify downstream mRNA targets.Results Circ_0012152 was significantly upregulated in samples from patients with AML and served as an independent adverse prognostic factor for overall survival(OS)(hazard ratio:2.357;95%confidence interval 1.258–4.415).The circ_0012152 knockdown reduced cell growth,increased apoptosis,and inhibited cell cycle progression in AML cell lines.RNA pull-down and sequencing identified miR-652-3p as a target microRNA of circ_0012152.Cell growth inhibition by circ_0012152 knockdown was significantly relieved by miR-652-3p inhibitors.We suggested that miR-652-3p targeted SOX4,as the decrease in SOX4 expression resulting from circ_0012152 knockdown was upregulated by miR-652-3p inhibitors in AML cells.Conclusion Circ_0012152 is an independent poor prognostic factor for OS in AML,and it promotes AML cell growth by upregulating SOX4 through miR-652-3p.展开更多
Cellular senescence is an irreversible cell cycle arrest triggered by the activation of oncogenes or mitogenic signaling as well as the enforced expression of tumor suppressors such as p53, p16INK4A and promyelocytic ...Cellular senescence is an irreversible cell cycle arrest triggered by the activation of oncogenes or mitogenic signaling as well as the enforced expression of tumor suppressors such as p53, p16INK4A and promyelocytic leukemia protein （PML） in normal cells. E2F-binding protein 1 （E2FBP1）, a transcription regulator for E2F, induces PML reduction and suppresses the formation of PML-nuclear bodies, whereas the down-regulation of E2FBP1 provokes the PML-dependent premature senescence in human normal fibroblasts. Here we report that the depletion of E2FBP1 induces the accumulation of PML through the Ras-dependent activation of MAP kinase signaling. The cellular levels of p16INK4A and p53 are elevated during premature senescence induced by depletion of E2FBP1, and the depletion of p16INK4A, but not p53 rescued senescent cells from growth arrest. Therefore, the premature senescence induced by E2FBP1 depletion is achieved through the pl6INK4A-Rb pathway. Similar to human normal fibroblasts, the growth inhibition induced by E2FBP1 depletion is also observed in human tumor cells with intact p16INK4A and Rb. These results suggest that E2FBP1 functions as a critical antagonist to the pI6INK4A-Rb tumor suppressor machinery by regulating PML stability.展开更多
Summary： Senescence is an important obstacle to cancer development. Engaging a senescent response may be an effective way to cure acute myeloid leukemia （AML）. The aim of this study was to examine the effect of res...Summary： Senescence is an important obstacle to cancer development. Engaging a senescent response may be an effective way to cure acute myeloid leukemia （AML）. The aim of this study was to examine the effect of resveratrol-downregulated phosphorylated liver kinase B1 （pLKB1） on the senescence of acute myeloid leukemia （AML） stem cells. The protein expressions of pLKB 1 and Sirtuin 1 （SIRT1）, a regulator ofpLKB1, were measured in CD34＋CD38-KGla cells treated with resveratrol （40 μmol/L） or not by Western blotting. Senescence-related factors were examined, including p21 mRNA tested by real-time PCR, cell morphology by senescence-associated β-galactosidase （SA-β-gal） staining, cell pro- liferation by MTT assay and cell cycle by flow cytometry. Besides, apoptosis was flow cytometrically determined. The results showed that pLKB1 was highly expressed in CD34＋CD38- KGla cells, and resveratrol, which could downregulate pLKB1 through activation of SIRT1, induced senescence and apoptosis of CD34＋CD38- KGla cells. It was concluded that resveratrol-downregulated pLKB1 is in- volved in the senescence of AML stem cells.展开更多
Objective: To investigate the expression of neuropilin-1 (NP-1) gene in bone marrow stromal cells (BMSCs) from myeloid leukemia (AML and CML) and normal individuals. Methods: Mononuclear cells were isolated from bone ...Objective: To investigate the expression of neuropilin-1 (NP-1) gene in bone marrow stromal cells (BMSCs) from myeloid leukemia (AML and CML) and normal individuals. Methods: Mononuclear cells were isolated from bone marrow (BM) of CML (14 cases), AML (12 cases) and normal individuals (20 cases). Adherent cells (i.e. BMSCs) were collected after long-term culture in vitro. The expression of NP-1 gene in three groups was detected respectively by reverse-transcription polymerase chain reaction (RT-PCR). Results: The long-term culture of BMSCs was successfully established. The expression level of NP-1 gene was significantly lower in BMSCs from AML (47.1%) and CML (50%) than in normal individuals (85%). Conclusion: NP-1 gene is expressed in BMSCs from some AML or CML patients and most normal individuals. The low-expression of NP-1 gene in BMSCs from AML or CML patients might be related with abnormality of regulation in hematopoiesis.展开更多
Objective： To investigate the association between the T cell inhibitory receptor programmed death 1（PD-1）and T cell exhaustion status in T cells from patients with de novo acute myeloid leukemia（AML） and AML in c...Objective： To investigate the association between the T cell inhibitory receptor programmed death 1（PD-1）and T cell exhaustion status in T cells from patients with de novo acute myeloid leukemia（AML） and AML in complete remission（CR）.Methods：Surface expression of PD-1 and the exhaustion and immunosenescence markers CD244 and CD57 on CD3＋,CD4＋ and CD8＋ T cells from peripheral blood samples from 20 newly diagnosed,untreated AML patients and 10 cases with AML in CR was analyzed by flow cytometry.Twenty-three healthy individuals served as control.Results：A significantly higher percentage of PD-1＋ cells were found for CD3＋ T cells in the de novo AML group compared with healthy controls.In addition,an increased level of PD-1＋ CD8＋ T cells,but not PD-1＋ CD4＋,was found for CD3＋ T cells in the de novo AML and AML-CR samples.A higher percentage of CD244＋ CD4＋,CD244＋ CD8＋,CD57＋ CD4＋ and CD57＋ CD8＋ T cells was found in CD3＋ T cells in samples from those with de novo AML compared with those from healthy controls.Strong increased PD-1＋ CD244＋ and PD-1＋ CD57＋ coexpression was found for CD4＋ and CD8＋ T cells in the de novo AML group compared with healthy controls.Conclusions：We characterized the major T cell defects,including co-expression of PD-1 and CD244,CD57-exhausted T cells in patients with de novo AML,and found a particular influence on CD8＋ T cells,suggesting a poor anti-leukemia immune response in these patients.展开更多
AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, ...AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, Western blotting and enzyme linked immunosorbent assay were conducted to identify the expression of HPPCn and the existence of an autocrine loop of HPPCn/ HPPCn receptor in SMMC7721 and HepG2.Apoptotic cells were detected using fluorescein isothiocyanate (FITC)-conjugated Annexin V and propidium iodide.RESULTS:The HPPCn was highly expressed in human HCC cells and secreted into culture medium(CM). FITC-labeled recombinant human protein(rhHPPCn) could specifically bind to its receptor on HepaG2 cells. Treatment with 400 ng/mL rhHPPCn dramatically increased the viability of HCC-derived cells from 48.1% and 36.9%to 85.6%and 88.4%,respectively(P< 0.05).HPPCn silenced by small-interfering RNA reduced the expression and secretion of HPPCn and increased the apoptosis induced by trichostatin A.Additionally, HPPCn could up-regulate the expression of myeloid cell leukemia-1(Mcl-1)in HCC cells via mitogen-activated protein kinase(MAPK)and sphingosine kinase-1. CONCLUSION:HPPCn is a novel hepatic growth factor that can be secreted to CM and suppresses apoptosis of HCC cells by up-regulating Mcl-1 expression.展开更多
基金supported by grants from the Natural Science Foundation of Zhejiang Province(No.LY20H080001)Medical and Health Science and Technology Projects of Zhejiang Province(No.2021KY997,No.2022KY306,No.2022KY316,No.2023KY263).
文摘Objective Acute myeloid leukemia(AML)is an aggressive hematological malignancy characterized by abnormal myeloid blast expansion.Recent studies have demonstrated that circular RNAs play a role in AML pathogenesis.In this study,we aimed to investigate the clinical significance of circ_0012152 in AML and elucidate its underlying molecular mechanism in the pathogenesis of this condition.Methods Circ_0012152 expression was detected by quantitative real-time polymerase chain reaction in samples obtained from 247 patients with AML and 40 healthy controls.A systematic analysis of clinical characteristics and prognostic factors was also conducted.Cell growth was assessed using the Cell Counting Kit-8(CCK-8)assay,and apoptosis and cell cycle progression were evaluated by flow cytometry.Moreover,RNA pull-down was performed to identify target microRNAs,and transcriptome RNA sequencing and bioinformatics analyses were utilized to identify downstream mRNA targets.Results Circ_0012152 was significantly upregulated in samples from patients with AML and served as an independent adverse prognostic factor for overall survival(OS)(hazard ratio:2.357;95%confidence interval 1.258–4.415).The circ_0012152 knockdown reduced cell growth,increased apoptosis,and inhibited cell cycle progression in AML cell lines.RNA pull-down and sequencing identified miR-652-3p as a target microRNA of circ_0012152.Cell growth inhibition by circ_0012152 knockdown was significantly relieved by miR-652-3p inhibitors.We suggested that miR-652-3p targeted SOX4,as the decrease in SOX4 expression resulting from circ_0012152 knockdown was upregulated by miR-652-3p inhibitors in AML cells.Conclusion Circ_0012152 is an independent poor prognostic factor for OS in AML,and it promotes AML cell growth by upregulating SOX4 through miR-652-3p.
基金supported by a Grant-in Aid for Scientific Research from the Japan Society for the Promotion of Science
文摘Cellular senescence is an irreversible cell cycle arrest triggered by the activation of oncogenes or mitogenic signaling as well as the enforced expression of tumor suppressors such as p53, p16INK4A and promyelocytic leukemia protein （PML） in normal cells. E2F-binding protein 1 （E2FBP1）, a transcription regulator for E2F, induces PML reduction and suppresses the formation of PML-nuclear bodies, whereas the down-regulation of E2FBP1 provokes the PML-dependent premature senescence in human normal fibroblasts. Here we report that the depletion of E2FBP1 induces the accumulation of PML through the Ras-dependent activation of MAP kinase signaling. The cellular levels of p16INK4A and p53 are elevated during premature senescence induced by depletion of E2FBP1, and the depletion of p16INK4A, but not p53 rescued senescent cells from growth arrest. Therefore, the premature senescence induced by E2FBP1 depletion is achieved through the pl6INK4A-Rb pathway. Similar to human normal fibroblasts, the growth inhibition induced by E2FBP1 depletion is also observed in human tumor cells with intact p16INK4A and Rb. These results suggest that E2FBP1 functions as a critical antagonist to the pI6INK4A-Rb tumor suppressor machinery by regulating PML stability.
基金supported by grants from the National Natural Science Foundation of China(Nos.81370660,81170524)
文摘Summary： Senescence is an important obstacle to cancer development. Engaging a senescent response may be an effective way to cure acute myeloid leukemia （AML）. The aim of this study was to examine the effect of resveratrol-downregulated phosphorylated liver kinase B1 （pLKB1） on the senescence of acute myeloid leukemia （AML） stem cells. The protein expressions of pLKB 1 and Sirtuin 1 （SIRT1）, a regulator ofpLKB1, were measured in CD34＋CD38-KGla cells treated with resveratrol （40 μmol/L） or not by Western blotting. Senescence-related factors were examined, including p21 mRNA tested by real-time PCR, cell morphology by senescence-associated β-galactosidase （SA-β-gal） staining, cell pro- liferation by MTT assay and cell cycle by flow cytometry. Besides, apoptosis was flow cytometrically determined. The results showed that pLKB1 was highly expressed in CD34＋CD38- KGla cells, and resveratrol, which could downregulate pLKB1 through activation of SIRT1, induced senescence and apoptosis of CD34＋CD38- KGla cells. It was concluded that resveratrol-downregulated pLKB1 is in- volved in the senescence of AML stem cells.
基金This work was supported by a grant from National Scaling Height Programm (95-zhuan-10).
文摘Objective: To investigate the expression of neuropilin-1 (NP-1) gene in bone marrow stromal cells (BMSCs) from myeloid leukemia (AML and CML) and normal individuals. Methods: Mononuclear cells were isolated from bone marrow (BM) of CML (14 cases), AML (12 cases) and normal individuals (20 cases). Adherent cells (i.e. BMSCs) were collected after long-term culture in vitro. The expression of NP-1 gene in three groups was detected respectively by reverse-transcription polymerase chain reaction (RT-PCR). Results: The long-term culture of BMSCs was successfully established. The expression level of NP-1 gene was significantly lower in BMSCs from AML (47.1%) and CML (50%) than in normal individuals (85%). Conclusion: NP-1 gene is expressed in BMSCs from some AML or CML patients and most normal individuals. The low-expression of NP-1 gene in BMSCs from AML or CML patients might be related with abnormality of regulation in hematopoiesis.
基金supported by grants from the National Natural Science Foundation of China (No. 81570143 and 91642111)the Guangdong Provincial Basic Research Program (No. 2015B020227003)+3 种基金the Guangdong Provincial Applied Science and Technology Research & Development Program (No. 2016B020237006)the Guangzhou Science and Technology Project (No. 201510010211)the Fundamental Research Funds for the Central Universities (No. 21616108)the Medical Scientific Research Foundation of Guangdong Province, China (No. A2016045)
文摘Objective： To investigate the association between the T cell inhibitory receptor programmed death 1（PD-1）and T cell exhaustion status in T cells from patients with de novo acute myeloid leukemia（AML） and AML in complete remission（CR）.Methods：Surface expression of PD-1 and the exhaustion and immunosenescence markers CD244 and CD57 on CD3＋,CD4＋ and CD8＋ T cells from peripheral blood samples from 20 newly diagnosed,untreated AML patients and 10 cases with AML in CR was analyzed by flow cytometry.Twenty-three healthy individuals served as control.Results：A significantly higher percentage of PD-1＋ cells were found for CD3＋ T cells in the de novo AML group compared with healthy controls.In addition,an increased level of PD-1＋ CD8＋ T cells,but not PD-1＋ CD4＋,was found for CD3＋ T cells in the de novo AML and AML-CR samples.A higher percentage of CD244＋ CD4＋,CD244＋ CD8＋,CD57＋ CD4＋ and CD57＋ CD8＋ T cells was found in CD3＋ T cells in samples from those with de novo AML compared with those from healthy controls.Strong increased PD-1＋ CD244＋ and PD-1＋ CD57＋ coexpression was found for CD4＋ and CD8＋ T cells in the de novo AML group compared with healthy controls.Conclusions：We characterized the major T cell defects,including co-expression of PD-1 and CD244,CD57-exhausted T cells in patients with de novo AML,and found a particular influence on CD8＋ T cells,suggesting a poor anti-leukemia immune response in these patients.
基金Supported by(in part)Grants From the National Natural Science Foundation of China,No.30800558 and No.30930041the Chinese Major Special Science&Technology Project for Development of Major New Drugs,No.2009ZX09103-617
文摘AIM:To investigate the role of hepatopoietin Cn(HPPCn) in apoptosis of hepatocellular carcinoma(HCC)cells and its mechanism. METHODS:Two human HCC cell lines,SMMC7721 and HepG2,were used in this study.Immunostaining, Western blotting and enzyme linked immunosorbent assay were conducted to identify the expression of HPPCn and the existence of an autocrine loop of HPPCn/ HPPCn receptor in SMMC7721 and HepG2.Apoptotic cells were detected using fluorescein isothiocyanate (FITC)-conjugated Annexin V and propidium iodide.RESULTS:The HPPCn was highly expressed in human HCC cells and secreted into culture medium(CM). FITC-labeled recombinant human protein(rhHPPCn) could specifically bind to its receptor on HepaG2 cells. Treatment with 400 ng/mL rhHPPCn dramatically increased the viability of HCC-derived cells from 48.1% and 36.9%to 85.6%and 88.4%,respectively(P< 0.05).HPPCn silenced by small-interfering RNA reduced the expression and secretion of HPPCn and increased the apoptosis induced by trichostatin A.Additionally, HPPCn could up-regulate the expression of myeloid cell leukemia-1(Mcl-1)in HCC cells via mitogen-activated protein kinase(MAPK)and sphingosine kinase-1. CONCLUSION:HPPCn is a novel hepatic growth factor that can be secreted to CM and suppresses apoptosis of HCC cells by up-regulating Mcl-1 expression.
