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@#Objective To investigate the effects of long non-coding RNA(LncRNA) growth arrest specific transcript 5(GAS5) negatively regulating nucleophosmin 1(NPM1) on cisplatin(DDP) resistance of gastric cancer cells.Methods The normal human gastric mucosa cell line GES-1 and human gastric cancer cell lines BG3-823,MGC-803 and AGS were selected as the research objects,of which the level of LncRNA GAS5 in each cell was measured by qRT-PCR.The drug resistance of AGS cells to DDP(AGS/DDP) was induced,and the experiment was divided into control group,empty plasmid group(BC group),GAS5 nonsense interference group(pLJM-GAS5 NC group) and GAS5 overexpression group(pLJM-GAS5 group).MTT method was used to determine the effect of DDP on the proliferation of AGS and AGS/DDP cells;and the levels of NPM1,multidrug resistance 1(MDR1),excision repair cross complementation group 1(ERCC1),multidrug resistance-associated protein 1(MRP1) and N-cadherin in AGS and AGS/DDP cells were measured by Western blot.Results Compared with the normal gastric mucosa GES-1 cells,the level of LncRNA GAS5 in BG3-823 and AGS cells decreased significantly,and among them,the level of LncRNA GAS5 in AGS cells was the lowest,so AGS cells were used for the follow-up experiments.Compared with the control group,the level of LncRNA GAS5 in AGS cells of BC group and pLJM-GAS5 NC group decreased significantly,while the levels of NPM1,MDRl,ERCC1,MRP1 and N-cadherin increased significantly;compared with BC group and pLJM-GAS5 NC group,the level of LncRNA GAS5 in AGS/DDP cells of pLJM-GAS5 group increased significantly,while the levels of NPM1,MDR1,ERCC1,MRP1 and N-cadherin decreased significantly;after treatment with DDP of the same concentration(except 0 μmol/L),compared with the control group,the inhibition rate of AGS/DDP cell proliferation in BC group and pLJM-GAS5 NC group decreased significantly;compared with BC group and pLJM-GAS5 NC group,the inhibition rate of AGS/DDP cell proliferation in pLJM-GAS5group was significantly higher.The semi inhibitory concentration(IC_(50)) of DDP on AGS/DDP cells in pLJM-GAS5 group for 48 h was(65.38±5.04) μmol/L,which was significantly lower than(120.74±4.17) μmol/L and(120.24±4.29) μmol/L in BC group and pLJM-GAS5 NC group.Conclusion Up-regulating the level of LncRNA GAS5 in AGS/DDP cells can reverse the drug resistance of AGS/DDP cells,which may be related to the down-regulation of NPM1expression
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Objective To explore the protein acetylation/succinylation and histone 2AX (H2AX) expression levels in breast cancer, as well as their correlation. Methods By Western blotting and RT-PCR methods to detect the protein modification and H2AX expression levels in 11 breast cancer tissues and cells, as well as to explore the common regulation way of protein acetylation and succinylation by treatment of histone deacetylase inhibitors ; To study the relationship between H2AX expression level and protein modification level through the construction and over-expression of indicated plasmids. Results Compared with the adjacent normal tissues, there existed an increase protein acetylation/succinylation levels in breast cancer tissues, and the protein acetylation and succinylation were both regulated by histone deacetylase (HDAC) members. The H2AX mRNA and protein expression levels were increased both in breast cancer cell and tissues, its expression level and the expression and modification level of represented protein nucleophosmin 1(NPM1) showed a positive correlation. Conclusion The breast cancer possesses a characteristic of high protein acetylation/succinylation levels and high H2AX expression level, the H2AX expression level and the modification level of partial proteins in breast cancer have a positive correlation.
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Objective: To investigate the effect of nucleophosmin 1 (NPM1) mutant A on TGF-β1-induced K562 cell proliferation and AKT phosphorylation. Methods: K562 cells were infected with Ad5-NPM1 to create an NPM1 over-expression cell model. NPM1 levels were determined by ELISA and Western blot analysis. The levels of AKT and P-AKT were determined by Western blot. MTT was used to measure the proliferation of K562 cells. Results: NPM1 protein levels in K562 cells increased in an Ad5-NPM1-MOI-dependent manner. Cell proliferation and NPM1 levels in the supernatant were significantly increased in K562 cells infected with Ad5-NPM1-30 and Ad5-NPM1-100 compared to those infected with Ad5-vector-100 (P<0.01). Treatment with (10 ng/mL) TGF-β1 increased P-AKT levels, but not total AKT levels in K562 cells. TGF-β1-induced phosphorylation of AKT was significantly increased by infection of K562 cells with Ad5-NPM1-100. No significant differences were found in total AKT levels among all groups. TGF-β1 (10 ng/mL) treatment also in-creased the proliferation of K562 cells. TGF-β1-induced K562 cell proliferation was significantly increased by infection with Ad5-NPM1-100 (P<0.01). Conclusions: NPM1 improves TGF-β1-induced cell proliferation by up-regulating AKT phosphorylation levels.
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Objective To investigate the effect of exogenous NPM mA to the subcellular localization of AKT and its significance in the proliferation in leukemia cells.Methods The co-immunoprecipitation assay was used to detect the interaction between NPM mA and AKT.The subcellular localization of NPM mA and AKT was observe by using the immunofluorescence experiment.The cells proliferation potential was assessed by CCK-8 assay.Results NPM mA could be combined with AKT in K562 cells.The immunofluorescence showed that NPM mA was mainly distributed in the cytoplasm.After co-tranfecting NPM mA and AKT into HEK293T cells,AKT was transformed from the dispersive distribution to cytoplasma.Additionally,the in vitro proliferation ability at 72 h in the K562 group was significantly enhanced compared with the K562 c1 and K562 mA groups(P＜0.01).After treating with AKT inhibitor(AKT inhibitor Ⅳ,AKT Ⅳ) for 48 h,the proliferation in the K562 c1 and K562 wt groups was remarkably inhibited,but which in the K562 mA group could still maintain growth(P＜0.01).Conclusion Exogenous NPM mA can change the subcellular localization of AKT,moreover regulates the in vitro malignant proliferation of leukemic cells.
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OBJECTIVE: To investigate the mechanism of nucleophosmin (NPM) in the formation of breast cancer drug resistance. METHODS: The methotrexate-resistant breast cancer cells (MCF-7 /MTX) was established by escalating the concentrations of methotrexate to drug-sensitive MCF-7 cells (MCF-7/S). The cells viability of MCF-7/MTX was detected by MTT test, cell growth curve was drawn and doubling time was calculated. The cell morphology and ultrastructure were observed using optical and transmission electron microscopy. The expression of NPM and factors related to drug resistance were tested by Real-time PCR and Western blot assay. Then the NPM level was attenuated by RNA interfering technology, and the resistance mechanism was explored in MCF-7/MTX cells. RESULTS The MCF-7/MTX cell line was successfully established and resistance factor was 64. The resistant cells has spindle shaped morphology and tended to grow slowly, and the variations appeared in the internal structure of cells. MCF-7/MTX cells possessed cross-resistance to various chemotherapeutic drugs. The expressions of NPM and multidrug-resistant factors P-gp, MRP1, BCRP were up-regulated in the resistant cells. Further, the overexpression of NPM activated PI3K/Akt signaling pathway and inhibited downstream apoptotic factors. Then knockdown of NPM by siRNA significantly decreased the drug resistance of MCF-7/MTX cells, suppressed PI3K/Akt pathway and promoted the downstream cells apoptosis. CONCLUSION The high expression of NPM has an important role in the formation of breast cancer drug resistance, and it is expected to be a novel molecular target for breast cancer treatment in clinical.
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Objective To investigate the clinical characteristics and efficacy of acute myeloid leukemia (AML) with NPM1 and FLT3 mutations.Methods NPM1 and FLT3 mutations were detected in 67 patients with newly diagnosed AML by PCR-capillary electrophoresis.The relationship was analyzed between the mutations and efficacy.Results The incidence of NPM1 mutation was 10.4％ (7/67) in total AML patients and 26.1％ (6/23) in normal karyotypes AML patients.The incidence of FLT3-ITD mutation was 10.4％ (7/67) in total AML patients and 17.4％ (4/23) in normal karyotypes AML patients.The characteristics of 60 NPM1 wild type patients vs that of 7 NPMl mutation patients was as follow,platelet count (BPC) (54× 109/L vs.27.5 × 109/L,P ＜ 0.01),proportion of AML-M5 (57.1％ vs.27.3％,P ＜ 0.01),incidence of CD34+ (28.6％ vs.63.3％,P＜0.01),normal karyotypes (85.7％ vs.28.3％,P＜0.01),cases with particular fusion gene (0 vs.48.3％,P ＜ 0.01),incidence of FLt3-1TD-mutations positive (28.6％ vs.8.3％,P ＜ 0.01),and the differences were significant (P＜0.01).No statistic difference was found in white blood cell(WBC) counts,percentage of blasts in bone marrow,sex,median age and complete remission rate between the two groups (P ＞0.05).The WBC counts (26.9 × 109/L vs.8.1 × 109/L,P =0.013),percentage of blastsin in bone marrow (90％ vs.76％,P=0.014) in the FLT3-ITD mutationg positive patients were clearly higher than those in the FLT3-ITD negative patients.If not associated with FLT3-ITD mutations,mutant NPM1 appears to identify patients with improved response toward treatment.Conclusion It is necessary to detect NPM1 mutation and FLT3-ITD mutation in newly diagnosed AML patients,especially in patients with normal karyotype,which might help to molecular classification and treatment.
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Acute myeloid leukaemia (AML) is one of the fatal haematological malignancies as a consequence of its genetic heterogeneity. At present, the prediction of the clinical response to treatment for AML is based not only on detection of cytogenetic aberrations but also by analysing certain molecular genetic alterations. There are limited in sights into the contribution, disease progression, treatment outcome, and characterisation with respect to the uncommon chromosomal abnormalities leading to AML. Here, we describe the clinical, morphological, cytogenetic, and mutational findings of a 52-year-old female patient with AML without maturation (AML-M1). Conventional karyotyping and spectral karyotyping (SKY) were done on metaphase chromosomes from bone marrow cells at the time of diagnosis. A mutation analysis was performed on the hotspot regions of various genes, including FLT3, CEBPA, NPM1, RAS, c-KIT, IDH1 and IDH2. Cytogenetic and mutation analyses revealed a novel translocation, t(X;2)(q28;p22), with both NPM1 and IDH1 mutations. To the best of our knowledge, the presence of both NPM1 and IDH1 mutations in t(X;2) (q28;p22) is a novel finding in AML.
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Background: Acute promyelocytic leukemia (APL) with t (15;17) is a distinct category of acute myeloid leukemia (AML) and is reported to show better response to anthracyclin based chemotherapy. A favorable overall prognosis over other subtypes of AML has been reported for APL patients but still about 15% patients relapse. Methods: This study evaluated the presence of Famus like tyrosine kinase‑3 (FLT3) and nucleophosmin‑1 (NPM1) gene mutations in a cohort of 40 APL patients. Bone marrow/peripheral blood samples from patients at the time of diagnosis and follow‑up were processed for immunophenotyping, cytogenetic markers and isolation of DNA and RNA. Samples were screened for the presence of mutations in FLT3 and NPM1 genes using polymerase chain reaction followed by sequencing. Results: Frequency of FLT3/internal tandem duplication and FLT3/tyrosine kinase domain was found to be 25% and 7% respectively. We observed a high frequency of NPM1 mutation (45%) in the present population of APL patients.
Subject(s)
Humans , India , Leukemia, Promyelocytic, Acute/epidemiology , Leukemia, Promyelocytic, Acute/genetics , Mutation/genetics , /genetics , Vascular Endothelial Growth Factor Receptor-1/geneticsABSTRACT
Nucleophosmin (NPM) is regularly identified as multifunctional nuclear protein which is widely expressed in different kinds of cells.NPM is identified not only as a potential regulator for cell proliferation,but also as an important player in tumor genesis procession.Aberrant expression of NPM,such as over-expression,rearrangement and mutation could lead to malignant transformation in solid tumor and leukemia cells.Over-expression of NPM had been detected as a poor prognostic factor and was related to drug-resistance development.It is reported that rearrangement of NPM gene played an important role in acute promyelocytic leukemia (APL,M3),myelodysplastic syndrome (MDS) and lymphoma.As the main molecular event in AML,NPM1 mutation occurred in kinds of subtypes of AML,which predicted a different prognosis.The aberrant expression of NPM in acute leukemia was reviewed.
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BACKGROUND: Genetic abnormalities in adult AML are caused most frequently by somatic mutations in exon 12 of the NPM1 gene, which is observed in approximately 35% of AML patients and up to 60% of patients with cytogenetically normal AML (CN-AML). METHODS: We performed mutational analysis, including fragment analysis and direct sequencing of exon 12 of the NPM1 gene, on 83 AML patients to characterize the NPM1 mutations completely. RESULTS: In this study, NPM1 mutations were identified in 19 (22.9%) of the 83 AML patients and in 12 (42.9%) of the 28 CN-AML patients. Among the 19 patients with NPM1 mutations, type A NPM1 mutations were identified in 16 (84.2%) patients, whereas non-A type NPM1 mutations were observed in 3 (15.8%) patients. Two of the 3 non-A type NPM1 mutations were novel: c.867_868insAAAC and c.869_873indelCTTTAGCCC. These 2 novel mutant proteins display a nuclear export signal motif (L-xxx-L-xx-V-x-L) less frequently and exhibit a mutation at tryptophan 290 that disrupts the nucleolar localization signal. CONCLUSIONS: This study suggests that novel NPM1 mutations may be non-rare and that supplementary sequence analysis is needed along with conventional targeted mutational analysis to detect non-A types of NPM1 mutations.
Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Amino Acid Motifs , Base Sequence , DNA Mutational Analysis , Exons , Leukemia, Myeloid, Acute/genetics , Mutation , Nuclear Proteins/geneticsABSTRACT
Background: Melanoma is quite a heterogeneous group of diseases of the skin. Prognostic markers of tumor behavior are important to precisely assign individual patients for appropriate treatment protocols. Aim: The aim of our first study was to investigate nucleophosmin expression in melanoma patients and to determine its relationship with the tumor characterictics and patient prognosis. Materials and Methods: We analyzed the immunohistochemical expression of nucleophosmin in 55 melanoma patients. The immunostaining pattern was classified into two groups: Diffuse nuclear and nucleolar relocalization. We also investigated the relationship between the expression of nucleophosmin and the clinicopathological parameters sucssh as Clark level, tumor thickness, stage, histological type, location, and survey. Results: In all cases the neoplastic cells were strongly positive for nucleophosmin (14 cases diffuse nuclear, 41 cases nucleolar relocalization). No correlation was demonstrated between the expression pattern of nucleophosmin and the clinicopathological parameters and survey. Conclusions: The implications of our results, nevertheless, are that the immunohistochemical detection of nucleophosmin is not a valuable tool for predicting the outcome of patients with melanoma or identifying subgroups of patients who may be at a higher risk.
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Immunohistochemistry , Male , Melanoma/diagnosis , Melanoma/pathology , Microscopy , Middle Aged , Nuclear Proteins/analysis , Prognosis , Retrospective Studies , Biomarkers, Tumor/analysisABSTRACT
BACKGROUND: Accumulation of genetic aberrations in MDS is closely associated with progression to AML. FLT3-ITD is commonly found in AML and less frequently in MDS. FLT3-ITD in MDS is associated with a high risk of transformation to AML. Recently, significant interaction of NPM1 and FLT3-ITD was described in AML. This study was conducted to investigate the incidence and prognostic role of FLT3-ITD and NPM1 mutations (NPM1mt) on paired samples at diagnosis of MDS and AML. METHODS: Patients who were diagnosed as MDS transforming to AML were included. FLT3-ITD was detected by PCR, and NPM1mt was confirmed by direct sequencing after screening for NPM by immunohistochemistry. RESULTS: AML developed in 12.0% (43/357) of MDS patients. FLT3-ITD was detected in none of MDS and 14.7% (5/34) of AML. NPM1mt was detected in 2.4% (1/41) of MDS and 11.6% (5/43) of AML. One patient with type B NPM1mt at MDS transformed to type A NPM1mt at AML. FLT3-ITD positive AML showed a tendency of shorter survival and a significantly longer time to achieve complete remission than FLT3-ITD negative AML (P=0.007). Normal karyotype AML with FLT3-ITD showed shorter overall survival than that group of AML without FLT3-ITD (P=0.017). CONCLUSIONS: MDS patients acquired FLT3-ITD during AML transformation, and FLT3-ITD positive AML, especially that with normal karyotype, predicted a poor outcome. NPM1mt was identified in both MDS and AML. NPM1mt was rarely found in MDS patients, and mostly was acquired after AML transformation. Clonal evolution of NPM1mt subtype was found in one patient during acute transformation.