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BACKGROUND: Primary liver cancer is a prevalent and deadly cancer type. Despite treatment advances, prognosis remains poor, with high recurrence rates. Early detection is crucial but challenging due to the disease's insidious nature. Myosin proteins play significant roles in cancer development, influencing cell migration, invasion, and tumor suppression. MYL6B, a myosin light chain, is involved in various cellular processes and has been associated with poor prognosis in colorectal adenocarcinoma and potential as a biomarker in breast cancer. AIM: To investigate the expression of MYL6B in liver hepatocellular carcinoma (LIHC) and its impact on prognosis and potential mechanisms of action using bioinformatics methods. METHODS: The expression of MYL6B in pan-cancer and normal tissues was analyzed using the gene expression profiling interactive analysis 2 and tumor immune estimation resource databases. The expression level of MYL6B in LIHC tissues and its relationship with prognosis were analyzed, immunohistochemical analysis of MYL6B and its effect on immune cell infiltration, and the protein network were further studied. RESULTS: MYL6B was highly expressed in diffuse large b-cell lymphoma, LIHC, pancreatic adenocarcinoma, skin cutaneous melanoma, thymoma, uterine corpus endometrial carcinoma, uterine carcinosarcoma, and lowly expressed in kidney chromophobe, acute myeloid leukemia, testicular germ cell tumors. The expression level of MYL6B was significantly different between cancer and normal tissues. It had a significant impact on both overall survival and disease-free survival. MYL6B is highly expressed in hepatocellular carcinoma and its expression level increases with cancer progression. High MYL6B expression is associated with poor prognosis in terms of overall survival and recurrence-free survival. The immunohistochemical level of MYL6B is high in hepatocellular carcinoma tissues, and MYL6B has a high level of immune infiltration inflammation. In protein network analysis, MYL6B is correlated with MYL2, MYL6, MYL9, MYLK4, MYLK2, MYL12A, MYL12B, MYH11, MYH9 and MYH10. CONCLUSION: The expression level of MYL6B in LIHC was significantly higher than in normal liver tissues, and it was correlated with the degree of differentiation survival rate, and immune infiltration. MYL6B is a potential target for LIHC treatment.
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As a well-known natural and innocuous plant constituent, cellulose consists of abundant hydroxyl groups and can tightly adsorb onto material surfaces hydrogen bonding, resulting in a superhydrophilic surface. In this work, the hydrophobic polyvinylidene fluoride (PVDF) membranes were modified by immersing them in cellulose hydrogel using a simple one-step process. The modified PVDF membrane exhibited excellent resistance to fouling and oil adhesion, making it highly effective in separating various oil-in-water emulsions. The cellulose-modified PVDF membranes achieved a high oil rejection rate (>99 %) and a maximum separation flux of 2675.2 L·m-2·h-1. Furthermore, even an oil-in-water emulsion containing bovine serum albumin maintained a steady permeation flux after four filtration cycles. Additionally, these cellulose-modified PVDF membranes demonstrated excellent underwater superoleophobicity across a wide range of pH levels and high saline conditions. Overall, these cellulose-modified superhydrophilic PVDF membranes are sustainable, environmentally friendly, easily scalable, and hold great promise for practical applications in oily wastewater treatment.
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Incrustação Biológica , Celulose , Polímeros de Fluorcarboneto , Polivinil , Celulose/química , Emulsões , Hidrogéis , ÓleosRESUMO
Alternative pre-mRNA splicing, which produces various mRNA isoforms with distinct structures and functions from a single gene, is regulated by specific RNA-binding proteins and is an essential method for regulating gene expression in mammals. Recent studies have shown that abnormal change during neuronal development triggered by splicing mis-regulation is an important feature of various neurological diseases. Polypyrimidine tract binding protein 1 (PTBP1) is a kind of RNA-binding proteins with extensive biological functions. As a well-known splicing regulator, it affects the neuronal development process through its involvement in axon formation, synaptogenesis, and neuronal apoptosis, according to the most recent studies. Here, we summarized the mechanism of alternative splicing, structure and function of PTBP1, and the latest research progress on the role of alternative splicing events regulated by PTBP1 in axon formation, synaptogenesis and neuronal apoptosis, to reveal the mechanism of PTBP1-regulated changes in neuronal development process.
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Doenças do Sistema Nervoso , Neurogênese , Proteína de Ligação a Regiões Ricas em Polipirimidinas , RNA , Animais , Mamíferos/genética , Mamíferos/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , RNA/metabolismo , Splicing de RNA , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Doenças do Sistema Nervoso/genética , Neurogênese/genéticaRESUMO
Risk-stratification of acute myeloid leukemia (AML) based on (cyto)genetic aberrations, including hotspot mutations, deletions and point mutations have evolved substantially in recent years. With the development of next-generation sequence technology, more and more novel mutations in the AML were identified. Thus, to unravel roles and mechanism of novel mutations would improve prognostic and predictive abilities. In this study, two novel germline JAK2 His608Tyr (H608Y) and His608Asn (H608N) mutations were identified and the molecular basis of these mutations in the leukemiagenesis of AML was elucidated. Our results indicated that JAK2 H608Y and H608N mutations disrupted the hydrogen bond between Q656 and H608 which reduced the JH2 domain's activity and abolished interactions between JH1 and JH2 domains, forced JAK2 into the active conformation, facilitated the entrance of substrates and thus caused JAK2 hyperactivation. Further studies suggested that JAK2 H608Y and H608N mutations enhanced the cell proliferation and inhibited the differentiation of Ba/F3 and MV4-11 cells via activating the JAK2-STAT5 signaling pathway. Moreover, rescue experiments demonstrated that mutations repaired the hydrogen bond between Q656 and H608 displayed opposite results. Thus, this study revealed the molecular basis of JAK2 H608Y and H608N mutations in the pathology of AML.
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Janus Quinase 2 , Leucemia Mieloide Aguda , Humanos , Janus Quinase 2/metabolismo , Mutação , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patologia , Proliferação de Células/genética , Transdução de Sinais/genética , Diferenciação CelularRESUMO
Central nervous system injury diseases can cause the loss of many neurons, and it is difficult to regenerate. The field of regenerative medicine believes that supplementing the missing neurons may be an ideal method for nerve injury repair. Recent studies have found that down-regulation of polypyrimidine tract binding protein 1 (PTBP1) expression can make glial cells transdifferentiate into different types of neurons, which is expected to be an alternative therapy to restore neuronal function. This article summarized the research progress on the structure and biological function of the PTBP family, the mutual regulation of PTBP1 and PTBP2, their role in neurogenesis, and the latest research progress in targeting PTBP1 to mediate the transdifferentiation of glial cells into neurons, which may provide some new strategies and new ideas for the future treatment of central nervous system injury and neurodegenerative diseases. This article is categorized under: RNA Processing > Splicing Regulation/Alternative Splicing.
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Transdiferenciação Celular , Proteína de Ligação a Regiões Ricas em Polipirimidinas , Fatores de Processamento de RNA/metabolismo , Proteína de Ligação a Regiões Ricas em Polipirimidinas/genética , Proteína de Ligação a Regiões Ricas em Polipirimidinas/química , Proteína de Ligação a Regiões Ricas em Polipirimidinas/metabolismo , Neurônios/metabolismo , Processamento Alternativo , Neuroglia/metabolismo , Ribonucleoproteínas Nucleares Heterogêneas/genética , Ribonucleoproteínas Nucleares Heterogêneas/metabolismoRESUMO
Polo-like kinase 4 (PLK4), a key regulator of centriole biogenesis, is frequently overexpressed in cancer cells. However, roles and the mechanism of PLK4 in the leukemiagenesis of acute myeloid leukemia (AML) remain unclear. In this study, the PLK4 inhibitor Centrinone and the shRNA knockdown were used to investigate roles and the mechanism of PLK4 in the leukemiagenesis of AML. Our results indicated that Centrinone inhibited the proliferation of AML cells in a dose- and time-dependent manner via reduced the expression of PLK4 both in the protein and mRNA levels. Moreover, colony formation assay revealed that Centrinone reduced the number and the size of the AML colonies. Centrinone induced AML cell apoptosis by increasing the activation of Caspase-3/poly ADP-ribose polymerase (PARP). Notably, Centrinone caused the G2/M phase cell cycle arrest by decreasing the expression of cell cycle-related proteins such as Cyclin A2, Cyclin B1, and Cyclin-dependent kinase 1 (CDK1). Consistent with above results, knockdown the expression of PLK4 also inhibited cell proliferation and colony formation, induced cell apoptosis, and caused G2/M phase cell cycle arrest without affecting cell differentiation. All in all, this study suggested that PLK4 inhibited the progression of AML in vitro, and these results herein may provide clues in roles of PLK4 in the leukemiagenesis of AML.
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PURPOSE: FLT3 mutations occurred in approximately one third of patients with acute myeloid leukemia (AML). FLT3-ITD mutations caused the constitutive activation of the RAS/MAPK signaling pathway. Ribosomal S6 Kinases (RSKs) were serine/threonine kinases that function downstream of the Ras/Raf/MEK/ERK signaling pathway. However, roles and mechanisms of RSKs inhibitor LJH-685, and combinational effects of LJH-685 and FLT3 inhibitor FF-10101 on AML cells were till unclear. METHODS: Cell viability assay, CFSE assay, RT-qPCR, Colony formation assay, PI stain, Annexin-V/7-AAD double stain, Western blot, and Xenogeneic transplantation methods were used to used to investigate roles and mechanisms of LJH-685 in the leukemogenesis of AML. RESULTS: LJH-685 inhibited the proliferation and clone formation of AML cells, caused cell cycle arrest and induced the apoptosis of AML cells via inhibiting the RSK-YB-1 signaling pathway. MV4-11 and MOLM-13 cells carrying FLT3-ITD mutations were more sensitive to LJH-685 than that of other AML cell lines. Further studies suggested that LJH-685 combined with Daunorubicin or FF- 10101 synergistically inhibited the cell viability, promoted the apoptosis and caused cycle arrest of AML cells carrying FLT3-ITD mutations. Moreover, in vivo experiments also indicated that LJH-685 combined with FF-10101 or Daunorubicin prolonged the survival time of NSG mice and reduced the leukemogenesis of AML. CONCLUSION: Thus, these observations demonstrated combination of RSK inhibitor LJH-685 and FLT3 inhibitor FF-10101 showed synergism anti-leukemia effects in AML cell lines with FLT3-ITD mutations via inhibiting MAPK-RSKs-YB-1 pathway and provided new targets for therapeutic intervention especially for AML with FLT3-ITD mutations and Daunorubicin-resistant AML.
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Leucemia Mieloide Aguda , Inibidores de Proteínas Quinases , Animais , Camundongos , Apoptose , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Daunorrubicina/farmacologia , Daunorrubicina/uso terapêutico , Tirosina Quinase 3 Semelhante a fms/genética , Tirosina Quinase 3 Semelhante a fms/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Mutação , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêuticoRESUMO
We report the case of a 20-year-old man with acne conglobata (AC) who was treated with 5-aminolevulinic acid photodynamic therapy (ALA-PDT) sequentially to deroofing, and finally used fractional carbon dioxide laser for esthetic requirements, achieving satisfying results. AC is a severe form of acne vulgaris that can lead to significant scarring and has serious negative effects on a patient's psychological well-being and quality of life. Some cases are likely resistant to currently available treatments. This report describes a promising, and effective method for the treatment of AC.
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Acne Conglobata , Acne Vulgar , Fotoquimioterapia , Acne Conglobata/tratamento farmacológico , Acne Vulgar/tratamento farmacológico , Adulto , Ácido Aminolevulínico/uso terapêutico , Humanos , Masculino , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Qualidade de Vida , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To investigate the relationship between the levels of ferritin, C-reactive protein (CRP), lactate dehydrogenase (LDH) and interleukin-6 (IL-6) in peripheral serum and cytokine release syndrome (CRS) in patients with relapse and/or refractory multiple myeloma (R/R MM) after receiving chimeric antigen receptor T cells (CAR-T) immunotherapy. METHODS: Twenty-eight patients with R/R MM were treated with 1×106/kg humanized CD19 CAR-T and mouse B cell maturation antigen CAR-T cells after pretreatment chemotherapy based on fludarabine and cyclophosphamide. The concentrations of ferritin, CRP, LDH, and IL-6 in peripheral blood were measured regularly within 30 days after infusion, and the correlation between severity of CRS and above indexes was analyzed. RESULTS: Among the 28 patients, 27 cases (96.4%) developed CRS, 24 cases (85.7%) in 1-2 grade CRS and 3 cases (10.7%) in 3-5 grade. The severity grade of CRS of 27 patients was positively correlated with the peak values of ferritin, CRP, LDH, and IL-6 in peripheral blood (r1=0.511, r2=0.375, r3=0.480, r4=0.632). The median peak values of ferritin, CRP, LDH and IL-6 in peripheral serum of patients with grade 3-5 CRS were significantly higher than those in patients with grade 0-2 CRS. CONCLUSION: After receiving CAR-T cellular immunotherapy, the incidence of CRS in patients with R/R MM is higher, but most of them are in grade 1 or 2. The severity of CRS is positively correlated with the levels of ferritin, CRP, LDH and IL-6 in peripheral blood.
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Mieloma Múltiplo , Receptores de Antígenos Quiméricos , Animais , Antígenos CD19 , Síndrome da Liberação de Citocina , Humanos , Imunoterapia Adotiva , Camundongos , Mieloma Múltiplo/terapia , Recidiva Local de NeoplasiaRESUMO
OBJECTIVE: To investigate the prognostic significance of CUEDC1 in patients with acute myeloid leukemia (non-M3). METHODS: 52 cases newly diagnosed AML (non-M3) were selected and enrolled in AML non-M3 group, at the same time, 10 cases of iron doficiency anemia were selected and enrolled in control group. The bone marrow mononuclear cells(BMMC) were isolated from bone marrow of patients, the expression level of CUEDC1 in BMMC was detected by RT-PCR, the expression level of CUEDC1 mRNA in BMMC of AML-subtype patients was compared. The AML patients were divided into low and high expression groups according to the expression level of CUEDC1 mRNA, and the complete remission rate after the first chemothrapy course was compared, and the relative expression level of CUEDC1 mRNA between the remission and the non-remission group were compared. RESULTS: CUEDC1 was expressed in BMMC of 52 newly diagnosed patients with AML (non-M3) of all subtypes, which was higher than that in control group (P<0.05), and the expression level of CUEDC1 mRNA in M5 patients was the highest (P<0.05). In CUEDC1 low expression group, induced complete remisson rate ï¼76.2%,16/21ï¼ after the first course of treatment seemed higher than that of the high expression groupï¼67.7%,21/31ï¼, but the difference was not statistically significant; the expression level of CUEDC1 mRNA in the remission group of patients with newly diagnosed AML(non-M3) was lower than that in the non-remission group(P<0.05). CONCLUSION: CUEDC1 is highly expressed in newly diagnosed patients with AML, among which the CUEDC1 mRNA expression level in M5 patients is the highest, the expression of CUEDC1 mRNA possibly relates to the prognosis of patients with AML.
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Peptídeos e Proteínas de Sinalização Intracelular , Leucemia Mieloide Aguda , Medula Óssea , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Ferro , Prognóstico , RNA Mensageiro/genéticaRESUMO
Activating mutations in JAK2 have been described in patients with various hematologic malignancies including acute myeloid leukemia (AML) and myeloproliferative neoplasms. However, mechanism of these mutations in JAK2's activity, structural stability and pathology of AML remains poorly understood. The JAK2 T875N somatic mutation has been detected in about 5.2% of AML patients. But the structural basis and mechanism of JAK2 T875N mutation in the pathology of AML is still unclear. Our results suggested that JAK2 T875N mutation disrupted the T875 and D873 interaction which destroyed the compact structure of JH1 domain, forced it into the active conformation, facilitated the entrance of substrate and thus led to JAK2 hyperactivation. Mutations (T875N, T875A, D873A and D873G) disrupted the T875 and D873 interaction enhanced JAK2's activity, decreased its structural stability and JH2 domain's activity which further enhanced JAK2's activity, while mutations (T875R, D873E, T875R/D873E) repaired this interaction displayed opposite results. Moreover, JAK2 T875N mutation enhanced the activity of JAK2-STAT5 pathway, promoted the proliferation and transformation of OCI-AML3 cells. This study provides clues in understanding structural basis of T875N mutation caused JAK2 hyperactivation and its roles in the pathology of AML.
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Transformação Celular Neoplásica/genética , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mieloide Aguda/patologia , Mutação , Diferenciação Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Ativação Enzimática/genética , Estabilidade Enzimática/genética , Humanos , Janus Quinase 2/química , Modelos Moleculares , Conformação ProteicaRESUMO
Janus tyrosine kinase 2 (JAK2) mediates downstream signaling of cytokine receptors in all hematological lineages, constitutively active somatic JAK2 mutations were important for the leukemogenesis of acute leukemia (AL). The JAK2 R867Q somatic mutation is detected in a subset of AL patients. However, roles of JAK2 R867Q mutation in the pathogenesis of AL remain unclear. In this study, homology modeling analysis showed that loss of interaction between R867 and Y613 disrupted the JAK2 JH1/JH2 domain's interactions was responsible for its activation. JAK2 R867Q and mutations (R867A and R867G) abolished this interaction caused JAK2 constitutive activation. While, mutations (R867K, Y613E, R867K/Y613E) repairing this interaction reduced JAK2 R867Q mutation's activity. Furthermore, our studies showed that abolished R867 and Y613 interaction disrupted JH1/JH2 domains' interactions and led to JAK2 constitutive activation. More importantly, mutations (R867Q, R867A and R867G) disrupted this interaction enhanced the activity of JAK2-STAT5 pathway and the proliferation of Ba/F3 and MV4-11 cells. Further study showed that JAK2 R867Q mutation promoted the expression of proliferation marker and inhibited the differentiation marker of Ba/F3 and MV4-11 cells. Thus our studies provide clues in understanding the pathogenesis of JAK2 R867Q mutation in AL.
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Janus Quinase 2/química , Janus Quinase 2/metabolismo , Leucemia/genética , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Mutação , Doença Aguda , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Humanos , Interleucina-3/farmacologia , Janus Quinase 2/genética , Leucemia/patologia , Modelos Moleculares , Proteínas Mutantes/genética , Redobramento de Proteína , Estrutura Secundária de Proteína/genética , Estrutura Terciária de Proteína/genéticaRESUMO
Oncogenic activation of tyrosine kinase signaling pathway is recurrent in human leukemia. The acquired Janus kinase 2 (JAK2) K607N somatic mutation was detected in about 6.8% of acute myeloid leukemia (AML) patients. However, roles of JAK2 K607N mutation in the leukemogenesis of AML remain unclear. In this study, loss of interaction between K607 and E877 was identified as key reasons for JAK2 K607N mutation constitutive activation. JAK2 K607N and mutations (K607A, K607G and E877A) abolished the K607 and E877 interaction caused JAK2 constitutive activation. While, mutations (K607R, E877D) repairing this interaction reduced K607N mutation's activity. Furthermore, our studies showed that disruption of K607 and E877 interaction abolished JH1/JH2 domains' interactions and led to JAK2 constitutive activation. More importantly, JAK2 K607N and mutations disrupted this interaction enhanced JAK2-STAT5 pathway activation and the proliferation of Ba/F3 cells. Thus our studies provide clues in understanding the leukemogenesis of JAK2 K607N mutation in AML.
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Janus Quinase 2 , Leucemia Mieloide Aguda , Proteínas de Neoplasias , Substituição de Aminoácidos , Linhagem Celular Tumoral , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Mutação de Sentido Incorreto , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Domínios Proteicos , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismoRESUMO
OBJECTIVE: To construct a lentiviral vector carrying human CUEDC1 gene, to establish leukemic cell line MOLT-4 stably expressing recombinant plasmid, to analyze the expression of CUEDC1 in MOLT-4 cells and to investigate its effect on the proliferation of MOLT-4 cells. METHODS: The CUEDC1 gene was amplified by RT-PCR, and then was subcloned into the lentiviral vector pCDH to generate a lentiviral vector pCDH-CUEDC1. Recombinant lentivirus was generated by co-transfection of 3 plasmids, and transfected into MOLT-4 cells. The Real-time PCR and Western blot were respectively applied to detect the expression of CUEDC1 mRNA and protein, the CCK-8 and colony formation assay were used to evaluate the effect of CUEDC1 on proliferation of MOLT-4 cells. RESULTS: The recombinant lentiviral vector pCDH-CUEDC1 had been constructed successfully. After infection of MOLT-4 cells with the lentivirus, the recombinant plasmid could stably up-regulate the expression of CUEDC1 and protein. The CCK-8 detection and colony formation assay showed that exogenous CUEDC1 could significantly promote cell growth and the colony formation of MOLT-4 cells. CONCLUSION: The recombinant lentiviral vector carrying human CUEDC1 has been successfully constructed, exogenous CUEDC1 can significantly promote cell growth and the colony formation of MOLT-4 cells.
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Proliferação de Células , Proteínas de Transporte , Linhagem Celular Tumoral , Vetores Genéticos , Humanos , Lentivirus , Proteínas de Membrana , Plasmídeos , TransfecçãoRESUMO
Downregulation of suppressor of cytokine signalling-1 (SOCS1) is one of the vital reasons for JAK1-STAT3 pathway activation in acute myeloid leukaemia (AML). CUE domain-containing 2 (CUEDC2) was a novel interacting partner of SOCS1 and a positive correlation between the expression of CUEDC2 and SOCS1 was confirmed in primary AML cells and AML cell lines without SOCS1 promoter methylation. We aimed to explore roles of CUEDC2 in regulating ubiquitin-mediated degradation of SOCS1 in the leukaemogenesis of AML.According to in vitro experiments, CUEDC2 overexpression increased the level of SOCS1 protein, suppressed JAK1-STAT3 pathway activation. The suppression of this pathway inhibited AML cells' proliferation by causing G1 arrest and enhanced AML cells' sensitivity to cytarabine and idarubicin. Similarity, downregulation of CUEDC2 produced opposite results. Knockout or low expression of CUEDC2 in mouse or AML patients displayed lower overall survival and event-free survival rates, compared with these mouse and AML patients had high-CUEDC2 expression. Mechanistic studies revealed that CUEDC2 overexpression attenuated SOCS1 ubiquitination, facilitated its stabilisation by enhancing SOCS1, Elongin C and Cullin-2 (CUL2) interactions, thus inhibited JAK1-STAT3 pathway and leukaemogenesis of AML. Therefore, our novel findings indicated that CUEDC2 interacted with SOCS1 to suppress SOCS1's ubiquitin-mediated degradation, JAK1-STAT3 pathway activation and leukaemogenesis of AML.
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Proteínas de Transporte/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Proteínas de Membrana/metabolismo , Proteína 1 Supressora da Sinalização de Citocina/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Apoptose/genética , Apoptose/fisiologia , Proteínas de Transporte/genética , Ciclo Celular/genética , Ciclo Celular/fisiologia , Linhagem Celular , Proliferação de Células/genética , Proliferação de Células/fisiologia , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Células HL-60 , Humanos , Imunoprecipitação , Células K562 , Leucemia Mieloide Aguda/genética , Proteínas de Membrana/genética , Camundongos , Ligação Proteica , Proteína 1 Supressora da Sinalização de Citocina/genética , Células U937RESUMO
OBJECTIVE: To investigate the effect of steadily down-regulating the expression of VE-cadherin on the chemotheraputic sensitivity of K562 cells, and explore its possible mechanism. METHODS: Specifically targeting interference sequences carrying human VE-cadherin were designed, the recombinant lentiviral vector containing the IRES-GFP and NEO segment was constructed; recombinant lentivirus was generated by three-plasmids packing system, and transfected into K562 cells, then the cells steadily down-regulated were sorted. CCK-8 assay was performed to evaluate the VE-cadherin of chemotherapeutic (Imatinib) sensitivity of K562 cells. The apoptosis was analyzed by flow cytometry with Annexin V/7-AAD double labeling. The expressions of CD133 and ALDH1 mRNA were determined by real time PCR. The protein expressions of VE-cadherin, BCR-ABL and ß-catenin were analyzed by Western blot. RESULTS: The recombinant lentiviral vector pLB-shVEC-NEO-IRES-GFP was successfully constructed, packed into the lentivirus, then the K562 cells steadily down-regulating VE-cadherin expression was obtained. When VE-cadherin was down-rengulated in K562 cells, the proliferation rate was reduced while the the apoptosis rate was increased; the mRNA levels of CD133 and ALDH1 also were reduced; BCR-ABL fusion protein was not obviously changed; the total ß-catenin protein, as well as the nuclear ß-catenin protein were decreased in the K562/shVEC cells. Conclution: K562 cells are more susceptible to chemotherapy when VE-cadherin is down-regulated, that may be realized via reducing the stability and the nuclear transfer of ß-catenin protein.
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Antígenos CD/metabolismo , Caderinas/metabolismo , Apoptose , Proliferação de Células , Proteínas de Fusão bcr-abl , Humanos , Células K562RESUMO
Janus tyrosine kinase 2 (JAK2) mediates downstream signaling of cytokine receptors in all hematological lineages, constitutively active somatic JAK2 mutations play key roles in the pathology of myeloproliferative neoplasms (MPNs). Recently, germline JAK2 mutations are also associated with triple-negative MPNs. A novel germline mutation JAK2 V625F is reported to be involved in a subset of MPNs patients. However, the pathogenesis of this mutation caused MPN is still unclear. In this study, the homology models of JAK2 V625F showed that the newly formed interaction between F625 and Y613 disrupted the JAK2 JH1-JH2 domain interactions was responsible for its activation, when F625 and Y613 interaction was disrupted, its activity significantly decreased. While, when this interaction was repaired whether by forming hydrogen bond or salt bond, it would cause JAK2 activation. Biochemical studies also demonstrated that JAK2 V625F mutation led to JAK2-STAT5 pathway activation and promoted the proliferation of BaF3 cells. Thus, our results herein provide clues to understand the mechanism JAK2 V625F mutation caused MPNs and give information for the development of JAK2 mutation specific inhibitors.
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Mutação em Linhagem Germinativa , Neoplasias Hematológicas , Janus Quinase 2 , Mutação de Sentido Incorreto , Transtornos Mieloproliferativos , Proteínas de Neoplasias , Transdução de Sinais , Substituição de Aminoácidos , Linhagem Celular Tumoral , Neoplasias Hematológicas/enzimologia , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/patologia , Humanos , Ligação de Hidrogênio , Janus Quinase 2/química , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Transtornos Mieloproliferativos/enzimologia , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/patologia , Proteínas de Neoplasias/química , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Fator de Transcrição STAT5/genética , Fator de Transcrição STAT5/metabolismoRESUMO
Although roles of somatic JAK2 mutations in clonally myeloproliferative neoplasms (MPNs) are well established, roles of germline JAK2 mutations in the pathogenesis of MPNs remain unclear. Recently, a novel activating, germline JAK2 F556V mutation was identified and involved in the pathogenesis of MPNs, but, its pathogenesis mechanism was still unknown. In this study, homology models of JAK2 demonstrated that F556 located between two threonine residues which interacted with ATP phosphate groups by hydrogen bonds, Thr555 with the γ-phosphate and Thr557 with the ß-phosphate in the active site of JAK2's JH2 domain. Moreover, the hydrogen bond between Thr557 and Arg715 played vital roles in sustaining the structural conformation of JH2's active site and JH1-JH2 domains' interactions. When F556 was replaced by other amino acids except Trp, the hydrogen bond, JH2 domain's structural conformation and JH1-JH2 domains' interactions disrupted for changing the helix between ß2 and ß3 strands which finally caused JAK2 activation. Mechanistic and functional studies showed that JAK2 F556V mutation disrupted JAK2 JH2 domain's activity, caused JAK2-STAT5 pathway activation and promoted the proliferation of BaF3 cells. Thus, our results herein may provide clues to understand the pathogenesis mechanism of JAK2 F556V mutation in the MPNs.
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Transformação Celular Neoplásica , Janus Quinase 2/química , Janus Quinase 2/genética , Mutação , Domínio Catalítico , Proliferação de Células , Estabilidade Enzimática , Humanos , Simulação de Dinâmica Molecular , Fosforilação , Redobramento de ProteínaRESUMO
OBJECTIVE: To investigate a modified protocol of establishing mouse Ph+ ALL model so as to provide a more convenient and more powerful tool for Ph+ ALL studies. METHODS: Immature B cells from BALB/c mice were transfected with the Mig190 retrovirus and infused into irradiated syngeneic mice. The immunophenotype was identified by flow cytometry, the BCR-ABL was identified by RT-PCR and Western blot. Leukemia cells isolated from sick mice were re-infused into syngeneic mice without irradiation. RESULTS: The acute lymphoblastic leukemia was established in mice after Mig190 retroviral transfection, the lymphoblasts were observed by blood smears, the immunophenotype of these leukemic cells was CD19+, and the BCR-ABL was detected by RT-PCR and Western blot, the immunophenotype was conformed as Ph+ ALL, the isolated leukemia cells infused into mice rapidly developed B-ALL. CONCLUSION: A new protocol is established to generate mice with Ph+ ALL. This mouse model can provide a more simple and effective tool in comparison with the conversional protocols.
Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras , Animais , Modelos Animais de Doenças , Proteínas de Fusão bcr-abl , Imunofenotipagem , Camundongos , Camundongos Endogâmicos BALB C , Cromossomo FiladélfiaRESUMO
CUEDC2, a CUE domain containing 2 protein, plays critical roles in many biological processes, such as cell cycle, inflammation and tumorigenesis. However, whether CUEDC2 was involved in tumorigenesis of glioma and the possible mechanism remains to be elucidated. In the present study, our results implied that the expression of CUEDC2 was lower in the glioma tissue and glioma cell lines than that of normal tissue and asctrocyte cells. Downregulation of endogenous CUEDC2 in glioma U251 cell lines by RNAi promoted the tumor cells proliferation, migration, invasion and glioma neurosphere formation, while, overexpression of CUEDC2 showed the opposite effect. Further studies showed that overexpression of CUEDC2 suppressed the activation and nuclear translocation of phosphorylated-STAT3 (p-STAT3) but the level of p-STAT3 increased after interfering with the expression of CUEDC2. Moreover, CUEDC2 expression has an inhibitory effect on the activation of NF-κB. Thus, our studies suggested that the decreased expression of CUEDC2 in glioma led to the activation of transcription factor STAT3 and NF-κB signaling pathway which may be related to the tumorigenicity in glioma.