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BACKGROUND: Recently, many studies have been conducted to examine immune response modification at epigenetic level, but the candidate effect of RNA 5-methylcytosine (m5 C) modification on tumor microenvironment (TME) of acute myeloid leukemia (AML) is still unknown at present. METHODS: We assessed the patterns of m5 C modification among 417 AML cases by using nine m5 C regulators. Thereafter, we associated those identified modification patterns with TME cell infiltration features. Additionally, stepwise regression and LASSO Cox regression analyses were conducted for quantifying patterns of m5 C modification among AML cases to establish the m5 C-score. Meanwhile, we validated the expression of genes in the m5C-score model by qRT-PCR. Finally, the present work analyzed the association between m5 C-score and AML clinical characteristics and prognostic outcomes. RESULTS: In total, three different patterns of m5 C modification (m5 C-clusters) were identified, and highly differentiated TME cell infiltration features were also identified. On this basis, evaluating patterns of m5 C modification in single cancer samples was important for evaluating the immune/stromal activities in TME and for predicting prognosis. In addition, the m5 C-score was established, which showed a close relation with the overall survival (OS) of test and training set samples. Moreover, multivariate Cox analysis suggested that our constructed m5 C-score served as the independent predicting factor for the prognosis of AML (hazard ratio = 1.57, 95% confidence interval = 1.38-1.79, p < 1e-5 ). CONCLUSIONS: This study shows that m5 C modification may be one of the key roles in the formation of diversity and complexity of TME. Meanwhile, assessing the patterns of m5 C modification among individual cancer samples is of great importance, which provides insights into cell infiltration features within TME, thereby helping to develop relevant immunotherapy and predict patient prognostic outcomes.
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Leucemia Mieloide Aguda , Microambiente Tumoral , Humanos , Microambiente Tumoral/genética , Leucemia Mieloide Aguda/genética , ARN , Diferenciación Celular , MetilaciónRESUMEN
Objective: This study aimed to investigate the role and mechanism of circular RNA PVT1 (circPVT1) in patients with acute myeloid leukemia (AML). Materials and Methods: The expression of circPVT1 in 23 patients with de novo AML (not acute promyelocytic leukemia, not APL) and cell lines were detected by RT-qPCR. Loss of function assays were carried out to explore the influence of silenced circPVT1 on the proliferation, migration, and apoptosis in the THP-1 cell line. CCK-8 assays, trans-well assays, and annexin V/PI staining assays were performed to assess proliferation, migration, and apoptosis, respectively. Results: CircPVT1 was highly expressed in AML patients and myeloid cell lines compared to healthy controls. Higher expression of circPVT1 was related to shorter overall survival (OS) and relapse-free survival (RFS) in AML patients. Cell viability and migration were inhibited and apoptosis was increased when circPVT1 was knocked down in THP-1 cells. Knockdown of circPVT1 resulted in marked suppression of c-Myc protein with no significant change in mRNA levels. We also found that circPVT1 knockdown markedly increased the phosphorylation of c-Myc Thr-58, which was responsible for c-Myc degradation. Silencing of c-Myc caused a significant decrease in CXCR4 mRNA and protein expression, whereas the overexpression of c-Myc caused the opposite result, suggesting that CXCR4 is a target molecule of c-Myc. Finally, we found that overexpression of c-Myc could partially reverse circPVT1 knockdown-induced anti-tumor effects on THP-1 cells in vitro. Conclusion: Our findings showed that circPVT1 was highly expressed in AML patients and was related to shorter OS and RFS. CircPVT1 may exert an oncogenic effect in THP-1 cells by stabilizing c-Myc protein expression and downstream target CXCR4 expression. These data indicate that circPVT1 may be a promising therapeutic target for AML.
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Leucemia Mieloide Aguda , ARN Circular , Receptores CXCR4 , Humanos , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular , Leucemia Mieloide Aguda/tratamiento farmacológico , Receptores CXCR4/genética , ARN Circular/genética , ARN MensajeroRESUMEN
A rare but clinically important diagnostic dilemma arises when cases meet the criteria for both acute myeloid leukemia with myelodysplasia-related changes (AML-MRC) and mixed phenotype acute leukemia, especially those that evolve from myelodysplastic syndrome. We describe a 56-year-old male patient who presented with cytopenias and was initially diagnosed with myelodysplastic syndrome with single lineage dysplasia. Nearly 1 year later, this patient progressed to acute leukemia, and his blast cells simultaneously expressed T-lymphoid and myeloid antigens. Cytogenetic analysis showed a 20q deletion, and next-generation sequencing showed mutations of ASXL1, NRAS, PHF6, RUNX1, TP53, and PIGA. He was diagnosed with AML-MRC with blasts of the mixed T/myeloid phenotype according to the latest World Health Organization guidelines. In accordance with the treatment principles of AML-MRC, we chose an AML-like regimen for four cycles, but the patient did not achieve remission. Finally, we adhered to the treatment principles of mixed phenotype acute leukemia, and he achieved remission after a course of ALL-like regimen chemotherapy.
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Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Análisis Citogenético , Humanos , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/genética , Masculino , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/diagnóstico , Síndromes Mielodisplásicos/genética , FenotipoRESUMEN
Objective: We retrospectively compared the outcomes of patients with severe aplastic anemia (SAA) who received haploidentical hematopoietic stem cell transplantation (haplo-HSCT) combined or not combined with umbilical cord-derived mesenchymal stem cells (UC-MSCs). Materials and Methods: A total of 101 patients with SAA were enrolled in this study and treated with haplo-HSCT plus UC-MSC infusion (MSC group, n=47) or haplo-HSCT alone (non-MSC group, n=54). Results: The median time to neutrophil engraftment in the MSC and non-MSC group was 11 (range: 8-19) and 12 (range: 8-23) days, respectively (p=0.049), with a respective cumulative incidence (CI) of 97.82% and 97.96% (p=0.101). Compared to the non-MSC group, the MSC group had a lower CI of chronic graft-versus-host disease (GVHD) (8.60±0.25% vs. 24.57±0.48%, p=0.048), but similar rates of grades II-IV acute GVHD (23.40±0.39% vs. 24.49±0.39%, p=0.849), grades III-IV acute GVHD (8.51±0.17% vs. 10.20±0.19%, p=0.765), and moderate-severe chronic GVHD (2.38±0.06% vs. 7.45±0.18%, p=0.352) were observed. The estimated 5-year overall survival (OS) rates were 78.3±6.1% and 70.1±6.3% (p=0.292) while the estimated 5-year GVHD-free, failure-free survival (GFFS) rates were 76.6±6.2% and 56.7±6.9% (p=0.045) in the MSC and non-MSC groups, respectively. Conclusion: In multivariate analysis, graft failure was the only adverse predictor for OS. Meanwhile, graft failure, grades III-IV acute GVHD, and moderate-severe chronic GVHD could predict worse GFFS. Our results indicated that haplo-HSCT combined with UC-MSCs infusion was an effective and safe option for SAA patients.
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Anemia Aplásica , Enfermedad Injerto contra Huésped , Trasplante de Células Madre Hematopoyéticas , Células Madre Mesenquimatosas , Anemia Aplásica/terapia , Enfermedad Injerto contra Huésped/etiología , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Humanos , Estudios Retrospectivos , Acondicionamiento Pretrasplante/métodos , Cordón UmbilicalRESUMEN
BACKGROUND: Both omacetaxine (HHT) and curcumin were shown to exhibit anti-proliferative effect on lymphoma cells. However, the role of combination of HHT with curcumin (HHT/curcumin combination) on lymphoma cells remains unclear. Thus, this study aimed to investigate the effect of HHT/curcumin combination on the proliferation, migration, and angiogenesis of lymphoma cells. METHODS: Cell counting kit-8 (CCK-8), Ki67 immunofluorescence and transwell assays were used to assess the viability, proliferation and migration of U937 and Raji cells respectively. In addition, tube formation assay was used to determine the effects of HHT/curcumin combination on angiogenesis in human umbilical vein endothelial cells (HUVECs). RESULTS: In this study, we found that HHT/curcumin combination significantly inhibited the proliferation, migration and invasion in U937 and Raji cells (all P < 0.01). In addition, combination treatment markedly inhibited the secreted levels of vascular endothelial growth factor (VEGF)-(A-D) (all P < 0.01) in Raji cells. Moreover, combination treatment exhibited anti-tumor effects in Raji cells, as shown by the decreased signals of phosphorylated VEGF receptor 2 (p-VEGFR2) and phosphorylated protein kinase B (p-Akt) (all P < 0.01). Meanwhile, combination treatment inhibited VEGFA levels (P < 0.01) in exosomes derived from Raji cells. Application of exosomes with downregulated VEGF to HUVECs notably inhibited proliferation, migration and tube formation of HUVECs, evidenced by the decreased signals of p-Akt, angiogenin-1, matrix metallopeptidase 2 (MMP2) and matrix metallopeptidase 9 (MMP9) (all P < 0.01). CONCLUSION: Our findings indicated that combination of HHT and curcumin could inhibit lymphoma cell growth and angiogenesis via inhibition of VEGF/Akt signaling pathway. These results suggested that HHT combined with curcumin might be regarded as a promising therapeutic approach for the treatment of lymphoma.
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Both homoharringtonine (HHT) and curcumin exhibit anti-proliferative effects on lymphoma cells, but the effects of combined HHT and curcumin treatment remain unclear. Here, we investigated the effects of HHT/curcumin combination on the proliferation, apoptosis, and invasion in lymphoma cells. CCK-8, flow cytometry, and transwell assays were used to assess proliferation, apoptosis, and invasion of U937 and Raji cells. p-Smad3, E-cadherin, and N-cadherin expression were also measured in Raji cells using Western blot assays. Combination of HHT and curcumin synergistically inhibited U937 and Raji cell proliferation and invasion. In addition, the combination treatment markedly increased apoptosis of Raji cells as evidenced by increased Bax, cleaved caspase 3, and cleaved caspase 9 expression. Meanwhile, the combination treatment promoted anti-tumor mechanisms in Raji cells as indicated by decreases in p-Smad3 and N-cadherin and increases in E-cadherin. In vivo experiments showed that the combination treatment suppressed tumor growth in a mouse Raji xenograft model. Our findings indicate that combination of HHT and curcumin inhibited lymphoma cell growth by downregulating the TGF-ß/Smad3 pathway. These results suggest that HHT combined with curcumin might be a promising therapeutic approach for the treatment of lymphoma.
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Antineoplásicos/farmacología , Curcumina/farmacología , Homoharringtonina/farmacología , Linfoma/tratamiento farmacológico , Extractos Vegetales/farmacología , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Antineoplásicos/uso terapéutico , Apoptosis , Cadherinas/metabolismo , Caspasa 3/metabolismo , Caspasa 9/metabolismo , Línea Celular Tumoral , Proliferación Celular , Cephalotaxus/química , Curcuma/química , Curcumina/uso terapéutico , Quimioterapia Combinada , Homoharringtonina/uso terapéutico , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Fitoterapia , Extractos Vegetales/uso terapéutico , Transducción de Señal , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína X Asociada a bcl-2/metabolismoRESUMEN
BACKGROUND: Diffuse large B-cell lymphoma (DLBCL) is a common type of the Non-Hodgkin lymphomas (NHLs) formed by the neoplastic transformation of mature B cells. As the first-line therapeutics, CHOP (cyclophosphamide/doxorubicin/vincristine/prednisone) chemotherapy and R-CHOP (Rituximab + CHOP), either using alone or in combination with GM-CSF, have achieved great efficacy in DLBCL patients. However, the underlying mechanisms are still largely unknown. METHODS: In the present study, the combination use of CHOP and R-CHOP with GM-CSF was used to evaluate their effects on the tumor immune microenvironment of DLBCL. CHOP and R-CHOP administration was found to inhibit the growth and metastasis of DLBCL, with a higher efficacy in R-CHOP-challenged DLBCL mice. The anti-tumor effect of CHOP and R-CHOP was further amplified by GM-CSF. RESULTS: CHOP and R-CHOP therapeutics potentiated the anti-tumor properties of macrophages, as evidenced by the increased M1 macrophage and the decreased M2 macrophage accumulation in DLBCL-bearing mice. In a co-culture system, macrophages primed with CHOP and R-CHOP therapeutics inhibited multiple malignant behaviors of DLCBL cells. Mechanistically, CHOP/R-CHOP suppressed the activation of AKT signaling. These anti-tumor effects of CHOP/R-CHOP were all augmented by GM-CSF. CONCLUSIONS: Our work provided new insights into the immune-regulatory roles of CHOP and R-CHOP in the treatment of DLBCL, as well as the synergistic effects of GM-CSF in CHOP and R-CHOP therapeutics. Although our results suggest the synergistic effect of GM-CSF on DLBCL already sensitive to CHOP and R-CHOP, however, future studies are warranted to explore the role of GM-CSF on R-CHOP-resistant DLBCL. Trial registration Not applicable.
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OBJECTIVE: This study aimed to explore the therapeutic effects of autologous peripheral blood stem cell transplantation (APBSCT) with Jiedu Xiaoluo decoction (JDX) on non-Hodgkin lymphoma (NHL). METHOD: B lymphoma cells A20 were used to establish nude mice-transplanted tumor model. The peripheral blood of mice was analyzed by automatic blood cell counter. Inflammatory cytokines in tumor tissues were measured by ELISA, real-time qRT-PCR, and western blotting assays. Immunohistochemical staining was employed to evaluate tumor cell growth and apoptosis. CCK8 and Transwell assays were used to detect cell viability, migration, and invasion. Cell apoptosis in vitro was evaluated with flow cytometry. RESULT: In the in vitro co-culture system of A20 cells and hemopoietic stem cells (HSC), JDX notably inhibited the proliferation, migration, and invasion and promoted apoptosis of A20 cells compared to HSC treatment alone. In animal tumor xenografts of NHL, the combination of APBSCT with JDX significantly promoted hematopoietic reconstitution, inhibited tumorigenesis of A20 cell, promoted the inflammatory microenvironment remission, inhibited cell proliferation, and promoted apoptosis compared to APBSCT alone. CONCLUSION: The combination of APBSCT with JDX might be an effective strategy to treat NHL through inhibiting tumorigenesis and reconstructing hematopoietic and immune microenvironment. Our finding provided a novel insight into the clinical application of Traditional Chinese Medicine (TCM) against NHL.
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OBJECTIVES: To investigate the role of Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in acute myeloid leukemia (AML) and analyze the potential regulatory network of MALAT1/miR-146a/ CXCR4. METHODS: The expressions of MALAT1, miR-146a and CXCR4 were performed by qRT-PCR and Western Blot. We conducted trans-well assay, CCK-8 assay and flow cytometry to evaluate the migration, proliferation and apoptosis of AML cells. Also by using luciferase reporter assay, we investigated the interaction between miR-146a and MALAT1 or CXCR4. RESULTS: Firstly, MALAT1 and CXCR4 were upregulated while miR-146a was downregulated in AML patients compared with healthy controls. We observed a negative correlation between miR-146a and MALAT1 or CXCR4, but a positive correlation between MALAT1 and CXCR4 in AML patients. MALAT1 knockdown inhibited migration and proliferation but induced apoptosis of HL-60 cells. MALAT1 restrained miR-146a expression by acting as a ceRNA. miR-146a regulated HL-60 cells migration, proliferation and apoptosis by directly targeting CXCR4 expression. Finally, we found that CXCR4 expression was downregulated by MALAT1 knockdown and partially restored by miR-146a abrogation. CONCLUSIONS: Our results showed that MALAT1 regulates migration, proliferation and apoptosis by sponging miR-146a to regulate CXCR4 expression in AML cells, providing novel insights into the role of MALAT1 as a therapeutic target in AML.
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Regulación Leucémica de la Expresión Génica , Leucemia Mieloide Aguda/genética , MicroARNs/genética , ARN Largo no Codificante/genética , Receptores CXCR4/genética , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Leucemia Mieloide Aguda/patología , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
BACKGROUND: Therapy-related acute promyelocytic leukemia (t-APL) is a rare complication observed in solitary bone plasmacytoma (SBP), and SBP after radiotherapy evolving to APL harboring the FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutation has never been reported. Here, we present the first case reported until now. CASE SUMMARY: We describe a 64-year-old woman who presented with lumbar pain and was initially diagnosed with SBP. However, after one year of radiotherapy treatment, this patient experienced a long-standing bone-marrow-suppressive period and finally developed APL harboring the FLT3-ITD mutation, as confirmed by analyses of clinical features, bone marrow morphology, flow cytometry, cytogenetic examination, and molecular biology. On admission, the patient had disseminated intravascular coagulation and intracranial hemorrhage, and the peripheral blood and bone marrow smear displayed abundant abnormal promyelocytes. Unfortunately, she died when the definite diagnosis was made. CONCLUSION: The patient with t-APL harboring FLT3-ITD mutation evolving from SBP after radiotherapy had not been reported and had poor clinical outcomes. FLT3-ITD mutation in t-APL may be a potential pathogenesis of leukemogenesis. We should consider the potential risk of secondary neoplasms in SBP patients after radiotherapy.
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BACKGROUND: Candida tropicalis is the most common non-albicans Candida species identified in immunocompromised patients, which often appears with high mortality. However, data on the outcomes of treatment for Candida tropicalis fungemia in patients with neutropenia remain limited. METHODS: In the present study, 90 neutropenic adult patients with proven Candida tropicalis fungemia, who received initial antifungal therapy, were retrospectively analyzed. RESULTS: These results revealed that the overall 8-day and 30-day mortality among patients in the entire data set were 22.2% and 33.3%, respectively. However, there was no significant difference between the survival and death group, in terms of baseline characteristics. The univariate analysis of risk factors identified the treatment with azole as a predictor of mortality, while treatments that containing amphotericin B were associated with reduced mortality. In addition, the survival rate on day 30 was observed in 60.7% (17/28) of patients who were initially treated with echinocandins, while this was observed in 86.4% (19/22, P=0.039) and 100% (13/13, P=0.024) of patients treated with amphotericin B plus echinocandins and amphotericin B, respectively. CONCLUSION: These data indicate for the first time that the initial therapy with amphotericin B-based agents was associated with a better survival rate and could be assessed as the optimal strategy for the treatment of Candida tropicalis fungemia in patients with neutropenia.
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BACKGROUND: Currently, acute myelocytic leukemia (AML) still has a poor prognosis. As a result, gene markers for predicting AML prognosis must be identified through systemic analysis of multi-omics data. METHODS: First of all, the copy number variation (CNV), mutation, RNA-Seq, and single nucleotide polymorphism (SNP) data, as well as those clinical follow-up data, were obtained based on The Cancer Genome Atlas (TCGA) database. Thereafter, all samples (n = 229) were randomized as test set and training set, respectively. Of them, the training set was used to screen for genes related to prognosis, and genes with mutation, SNP or CNV. Then, shrinkage estimate was used for feature selection of all the as-screened genes, to select those stable biomarkers. Eventually, a prognosis model related to those genes was established, and validated within the GEO verification (n = 124 and 72) and test set (n = 127). Moreover, it was compared with the AML prognosis prediction model reported in literature. RESULTS: Altogether 832 genes related to prognosis, 23 related to copy amplification, 774 associated with copy deletion, and 189 with significant genomic variations were acquired in this study. Later, genes with genomic variations and those related to prognosis were integrated to obtain 38 candidate genes; eventually, a shrinkage estimate was adopted to obtain 10 feature genes (including FAT2, CAMK2A, TCERG1, GDF9, PTGIS, DOC2B, DNTTIP1, PREX1, CRISPLD1 and C22orf42). Further, a signature was established using these 10 genes based on Cox regression analysis, and it served as an independent factor to predict AML prognosis. More importantly, it was able to stratify those external verification, test and training set samples with regard to the risk (P < 0.01). Compared with the prognosis prediction model reported in literature, the model established in this study was advantageous in terms of the prediction performance. CONCLUSION: The signature based on 10 genes had been established in this study, which is promising to be used to be a new marker for predicting AML prognosis.
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The selection of chemotherapy regimen for elderly patients with acute myeloid leukemia (AML) remains challenging. Here, we report that granulocyte colony-stimulating factor (G-CSF) upregulates the expression of microRNA (miR)-146a in a nuclear factor kappaB-dependent manner, leading to direct decreases in the expression of the target proteins CXCR4 and Smad4 in AML cells in vitro. The reduction in CXCR4 expression suppressed the migration abilities of leukemia cells. Downregulation of Smad4 promoted cell cycle entry in leukemia cells. Furthermore, an increase in apoptosis was observed when leukemia cells were treated sequentially with G-CSF and cytosine arabinoside in vitro. These findings suggest that G-CSF treatment may disrupt the protection of bone marrow niches from leukemia cells. In a review of data from 78 cases of primary AML, we found that a high miR-146a expression and/or upregulation of this miRNA during G-CSF priming chemotherapy was predictive of better clinical outcomes. Our findings suggest that miR-146a may be a novel biomarker for evaluating the clinical prognosis and treatment effects of a G-CSF priming protocol in elderly patients with AML.
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Regulación Leucémica de la Expresión Génica/efectos de los fármacos , Factor Estimulante de Colonias de Granulocitos/farmacología , Leucemia Mieloide Aguda/tratamiento farmacológico , MicroARNs/fisiología , ARN Neoplásico/fisiología , Aclarubicina/administración & dosificación , Aclarubicina/efectos adversos , Aclarubicina/farmacología , Factores de Edad , Anciano , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimiotaxis/efectos de los fármacos , Técnicas de Cocultivo , Citarabina/administración & dosificación , Citarabina/efectos adversos , Citarabina/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Femenino , Factor Estimulante de Colonias de Granulocitos/administración & dosificación , Factor Estimulante de Colonias de Granulocitos/efectos adversos , Células HL-60 , Humanos , Leucemia Mielomonocítica Aguda/tratamiento farmacológico , Masculino , MicroARNs/biosíntesis , MicroARNs/genética , Persona de Mediana Edad , FN-kappa B/metabolismo , Proteínas de Neoplasias/biosíntesis , Proteínas de Neoplasias/genética , Pronóstico , Interferencia de ARN , ARN Neoplásico/biosíntesis , ARN Neoplásico/genética , ARN Interferente Pequeño/genética , Receptores CXCR4/biosíntesis , Receptores CXCR4/genética , Proteína Smad4/biosíntesis , Proteína Smad4/genética , Nicho de Células Madre , Microambiente Tumoral , Regulación hacia Arriba/efectos de los fármacosRESUMEN
Combining cytarabine, aclarubicin and granulocyte colony-stimulating factor (G-CSF) has demonstrated marked efficacy in the treatment of elderly and relapsed/refractory patients with acute myeloid leukemia (AML); however, the role of G-CSF remains poorly understood. The present study aimed to investigate the ability of G-CSF to overcome stromal-mediated drug resistance and the underlying molecular mechanism. Two types of co-culture models were established in the HS-5 human bone marrow/stromal and HL-60 human promyelocytic leukemia cell lines, in order to imitate the interactions between stromal and leukemia cells in vitro, which is mediated by the stromal cell-derived factor (SDF)-1α signaling axis. In the present study, HL-60 cells were attracted and adhered to HS-5 cells using migration assay and flow cytometry, respectively; however, these interactions were inhibited by treatment with G-CSF and/or the C-X-C chemokine receptor type 4 (CXCR4) antagonist, AMD3100. Co-culture with HS-5 cells, including direct and indirect contact, protected HL-60 cells against spontaneous apoptosis or drug-induced apoptosis; however, these protective effects were disrupted by treatment with G-CSF and/or AMD3100. Notably, G-CSF and/or AMD3100 did not alter cell viability or apoptosis when HL-60 cells were cultured with medium alone. In addition, G-CSF significantly reduced the expression levels of surface CXCR4 protein, total CXCR4 protein and CXCR4 mRNA, and significantly upregulated the expression of microRNA (miR)-146a. Conversely, AMD3100 significantly reduced surface CXCR4 expression levels, but not the total CXCR4, CXCR4 mRNA or miR-146a expression levels. The results of the present study suggested that interfering with the CXCR4/SDF-1α signaling axis via G-CSF inhibited the migration and adhesion of HL-60 cells to HS-5 cells and eliminated HS5 cell-mediated protective effects. Furthermore, G-CSF administration reduced CXCR4 expression levels by upregulating the expression of miR-146a, whereas AMD3100 appeared to be predominantly dependent on receptor internalization. Therefore, a G-CSF/miR-146a/CXCR4 pathway may explain how G-CSF inhibits CXCR4/SDF-1α signaling and overcomes stromal cell-mediated drug resistance in acute myeloid leukemia.
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In the presence of catalytic amount of copper iodide, a remote amide-assisted intramolecular arylation followed by alkylation leads to a general and flexible synthetic method toward the synthesis of medicinally interesting hexahydropyrroloindole alkaloids.