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Introduction: Acute myeloid leukemia (AML) is an aggressive blood cancer with high heterogeneity and poor prognosis. Although the metabolic reprogramming of nicotinamide adenine dinucleotide (NAD) has been reported to play a pivotal role in the pathogenesis of acute myeloid leukemia (AML), the prognostic value of NAD metabolism and its correlation with the immune microenvironment in AML remains unclear. Methods: We utilized our large-scale RNA-seq data on 655 patients with AML and the NAD metabolism-related genes to establish a prognostic NAD metabolism score based on the sparse regression analysis. The signature was validated across three independent datasets including a total of 1,215 AML patients. ssGSEA and ESTIMATE algorithms were employed to dissect the tumor immune microenvironment. Ex vivo drug screening and in vitro experimental validation were performed to identify potential therapeutic approaches for the high-risk patients. In vitro knockdown and functional experiments were employed to investigate the role of SLC25A51, a mitochondrial NAD+ transporter gene implicated in the signature. Results: An 8-gene NAD metabolism signature (NADM8) was generated and demonstrated a robust prognostic value in more than 1,800 patients with AML. High NADM8 score could efficiently discriminate AML patients with adverse clinical characteristics and genetic lesions and serve as an independent factor predicting a poor prognosis. Immune microenvironment analysis revealed significant enrichment of distinct tumor-infiltrating immune cells and activation of immune checkpoints in patients with high NADM8 scores, acting as a potential biomarker for immune response evaluation in AML. Furthermore, ex vivo drug screening and in vitro experimental validation in a panel of 9 AML cell lines demonstrated that the patients with high NADM8 scores were more sensitive to the PI3K inhibitor, GDC-0914. Finally, functional experiments also substantiated the critical pathogenic role of the SLC25A51 in AML, which could be a promising therapeutic target. Conclusion: Our study demonstrated that NAD metabolism-related signature can facilitate risk stratification and prognosis prediction in AML and guide therapeutic decisions including both immunotherapy and targeted therapies.
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Biomarcadores Tumorais , Leucemia Mieloide Aguda , NAD , Microambiente Tumoral , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/imunologia , Prognóstico , NAD/metabolismo , Microambiente Tumoral/imunologia , Microambiente Tumoral/genética , Biomarcadores Tumorais/genética , Feminino , Masculino , Pessoa de Meia-Idade , Regulação Leucêmica da Expressão Gênica , Perfilação da Expressão Gênica , Transcriptoma , Linhagem Celular TumoralRESUMO
Patients with primary refractory acute myeloid leukemia (AML) have a dismal long-term prognosis. Elucidating the resistance mechanisms to induction chemotherapy could help identify strategies to improve AML patient outcomes. Herein, we retrospectively analyzed the multiomics data of more than 1,500 AML cases and found that patients with spliceosome mutations had a higher risk of developing refractory disease. RNA splicing analysis revealed that the mis-spliced genes in refractory patients converged on translation-associated pathways, promoted mainly by U2AF1 mutations. Integrative analyses of binding and splicing in AML cell lines substantiated that the splicing perturbations of mRNA translation genes originated from both the loss and gain of mutant U2AF1 binding. In particular, the U2AF1S34F and U2AF1Q157R mutants orchestrated the inclusion of exon 11 (encoding a premature termination codon) in the eukaryotic translation initiation factor 4A2 (EIF4A2). This aberrant inclusion led to reduced eIF4A2 protein expression via nonsense-mediated mRNA decay. Consequently, U2AF1 mutations caused a net decrease in global mRNA translation that induced the integrated stress response (ISR) in AML cells, which was confirmed by single-cell RNA sequencing. The induction of ISR enhanced the ability of AML cells to respond and adapt to stress, contributing to chemoresistance. A pharmacologic inhibitor of ISR, ISRIB, sensitized U2AF1 mutant cells to chemotherapy. These findings highlight a resistance mechanism by which U2AF1 mutations drive chemoresistance and provide a therapeutic approach for AML through targeting the ISR pathway. SIGNIFICANCE: U2AF1 mutations induce the integrated stress response by disrupting splicing of mRNA translation genes that improves AML cell fitness to enable resistance to chemotherapy, which can be targeted to improve AML treatment.
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Resistencia a Medicamentos Antineoplásicos , Leucemia Mieloide Aguda , Mutação , Fator de Processamento U2AF , Humanos , Fator de Processamento U2AF/genética , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/genética , Splicing de RNA/genética , Animais , Estudos Retrospectivos , Camundongos , Linhagem Celular Tumoral , Fator de Iniciação 4A em Eucariotos/genética , Fator de Iniciação 4A em Eucariotos/metabolismoRESUMO
Through utilizing density functional theory (DFT), the current work investigates the potential uses of Al24P24 fullerene for detecting CS2, H2S, SO2, and COS. The interaction order for the stability of these gases was SO2 > H2S > COS > CS2. The moment of electric dipole and molecules' adsorption energy seems correlated. Al24P24 fullerene is regarded as an electronic sensor of the Ф-type for detecting SO2 and CS2. According to the findings, CS2 and SO2 might act as Al24P24 fullerenes when H2S is present. Nevertheless, we cannot presume it to be a COS and H2S sensor of Ф-type. At room temperature, the fullerene of Al24P24 has a quick recovery time of 0.50 µs and 0.17 s in CS2 and SO2 desorption from the surface. It can thus be inferred that it has the ability to function in moist media.
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CONTEXT: Ab initio calculations were employed in this investigation to scrutinize the adsorption characteristics of a linear chain (HF)n on a BN nanocage (B24N24), wherein the chain lengths varied (n = 1, 2, 3, and 4). The overarching aim was to assess the efficiency of this setup in detecting and adhering to (HF)n under both liquid and gaseous scenarios. This study encompassed an array of aspects, encompassing adsorption energy, optimal configuration determination, work function analysis, and charge exchange assessment. Furthermore, an exploration was conducted into the impact of HF linear chain dimensions on electrical attributes and adsorption energy. According to the values of adsorption energy, the dimer form of HF adsorbed onto BN nanocages displayed the highest stability. METHODS: This scrutiny was undertaken utilizing density functional theory (DFT), employing the B3LYP functional and the 6-31 + + G(d,p) basis set. Notably, the choice of the 6-31 + + G(d,p) basis set is particularly apt for delving into nanostructure analyses. The HOMO-LUMO energy gap was significantly reduced by (HF)n upon adsorption onto the nanocage, falling from 6.48 to 5.43 eV and enhancing electrical conductivity as a result. Additionally, BN nanocages may be used as sensors to find (HF)n among other environmental pollutants.
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Introduction: Colorectal cancer is one of the most common gastrointestinal cancers and the second leading cause of cancer-related death. Although colonoscopy screening has greatly improved the early diagnosis of colorectal cancer, its recurrence and metastasis are still significant problems. Tumour cells usually have the hallmark of metabolic reprogramming, while fatty acids play important roles in energy storage, cell membrane synthesis, and signal transduction. Many pathways of fatty acid metabolism (FAM) are involved in the occurrence and development of colon cancer, and the complex molecular interaction network contains a variety of genes encoding key enzymes and related products. Methods: Clinical information and RNA sequencing data were collected from TCGA and GEO databases. The prognosis model of colon cancer was constructed by LASSO-Cox regression analysis among the selected fatty acid metabolism genes with differential expression. Nomogram for the prognosis model was also constructed in order to analyze its value in evaluating the survival and clinical stage of the colon cancer patients. The differential expression of the selected genes was verified by qPCR and immunohistochemistry. GSEA and GSVA were used to analyze the enrichment pathways for high- and low-risk groups. CIBERSORT was used to analyze the immune microenvironment of colon cancer and to compare the infiltration of immune cells in the high- and low-risk groups. The "circlize" package was used to explore the correlation between the risk score signature and immunotherapy for colon cancer. Results: We analysed the differential expression of 704 FAM-related genes between colon tumour and normal tissue and screened 10 genes with prognostic value. Subsequently, we constructed a prognostic model for colon cancer based on eight optimal FAM genes through LASSO Cox regression analysis in the TCGA-COAD dataset, and its practicality was validated in the GSE39582 dataset. Moreover, the risk score calculated based on the prognostic model was validated as an independent prognostic factor for colon cancer patients. We further constructed a nomogram composed of the risk score signature, age and American Joint Committee on Cancer (AJCC) stage for clinical application. The colon cancer cohort was divided into high- and low-risk groups according to the optimal cut-off value, and different enrichment pathways and immune microenvironments were depicted in the groups. Discussion: Since the risk score signature was significantly correlated with the expression of immune checkpoint molecules, the prognostic model might be able to predict the immunotherapy response of colon cancer patients. In summary, our findings expand the prognostic value of FAM-related genes in colon cancer and provide evidence for their application in guiding immunotherapy.