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1.
JCI Insight ; 9(9)2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38716731

RESUMEN

T cells are required for protective immunity against Mycobacterium tuberculosis. We recently described a cohort of Ugandan household contacts of tuberculosis cases who appear to "resist" M. tuberculosis infection (resisters; RSTRs) and showed that these individuals harbor IFN-γ-independent T cell responses to M. tuberculosis-specific peptide antigens. However, T cells also recognize nonprotein antigens via antigen-presenting systems that are independent of genetic background, known as donor-unrestricted T cells (DURTs). We used tetramer staining and flow cytometry to characterize the association between DURTs and "resistance" to M. tuberculosis infection. Peripheral blood frequencies of most DURT subsets were comparable between RSTRs and latently infected controls (LTBIs). However, we observed a 1.65-fold increase in frequency of MR1-restricted T (MR1T) cells among RSTRs in comparison with LTBIs. Single-cell RNA sequencing of 18,251 MR1T cells sorted from 8 donors revealed 5,150 clonotypes that expressed a common transcriptional program, the majority of which were private. Sequencing of the T cell receptor α/T cell receptor δ (TCRα/δ) repertoire revealed several DURT clonotypes were expanded among RSTRs, including 2 MR1T clonotypes that recognized mycobacteria-infected cells in a TCR-dependent manner. Overall, our data reveal unexpected donor-specific diversity in the TCR repertoire of human MR1T cells as well as associations between mycobacteria-reactive MR1T clonotypes and resistance to M. tuberculosis infection.


Asunto(s)
Mycobacterium tuberculosis , Humanos , Mycobacterium tuberculosis/inmunología , Uganda , Adulto , Masculino , Antígenos de Histocompatibilidad Menor/inmunología , Antígenos de Histocompatibilidad Menor/genética , Femenino , Tuberculosis/inmunología , Tuberculosis/microbiología , Linfocitos T/inmunología , Tuberculosis Latente/inmunología , Tuberculosis Latente/microbiología , Células Clonales/inmunología , Resistencia a la Enfermedad/inmunología , Resistencia a la Enfermedad/genética , Adulto Joven , Antígenos de Histocompatibilidad Clase I
2.
BMC Cancer ; 24(1): 410, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566115

RESUMEN

BACKGROUND: High expression of the glycosyltransferase UGT2B17 represents an independent adverse prognostic marker in chronic lymphocytic leukemia (CLL). It also constitutes a predictive marker for therapeutic response and a drug resistance mechanism. The key determinants driving expression of the UGT2B17 gene in normal and leukemic B-cells remain undefined. The UGT2B17 transcriptome is complex and is comprised of at least 10 alternative transcripts, identified by previous RNA-sequencing of liver and intestine. We hypothesized that the transcriptional program regulating UGT2B17 in B-lymphocytes is distinct from the canonical expression previously characterized in the liver. RESULTS: RNA-sequencing and genomics data revealed a specific genomic landscape at the UGT2B17 locus in normal and leukemic B-cells. RNA-sequencing and quantitative PCR data indicated that the UGT2B17 enzyme is solely encoded by alternative transcripts expressed in CLL patient cells and not by the canonical transcript widely expressed in the liver and intestine. Chromatin accessible regions (ATAC-Seq) in CLL cells mapped with alternative promoters and non-coding exons, which may be derived from endogenous retrotransposon elements. By luciferase reporter assays, we identified key cis-regulatory STAT3, RELA and interferon regulatory factor (IRF) binding sequences driving the expression of UGT2B17 in lymphoblastoid and leukemic B-cells. Electrophoretic mobility shift assays and pharmacological inhibition demonstrated key roles for the CLL prosurvival transcription factors STAT3 and NF-κB in the leukemic expression of UGT2B17. CONCLUSIONS: UGT2B17 expression in B-CLL is driven by key regulators of CLL progression. Our data suggest that a NF-κB/STAT3/IRF/UGT2B17 axis may represent a novel B-cell pathway promoting disease progression and drug resistance.


Asunto(s)
Leucemia Linfocítica Crónica de Células B , FN-kappa B , Humanos , FN-kappa B/metabolismo , Leucemia Linfocítica Crónica de Células B/tratamiento farmacológico , Pronóstico , Apoptosis , ARN , Glucuronosiltransferasa/genética , Antígenos de Histocompatibilidad Menor
3.
Sci Rep ; 14(1): 7967, 2024 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-38575661

RESUMEN

Behçet's disease (BD) manifests as an autoimmune disorder featuring recurrent ulcers and multi-organ involvement, influenced by genetic factors associated with both HLA and non-HLA genes, including TNF-α and ERAP1. The study investigated the susceptible alleles of both Class I and II molecules of the HLA gene in 56 Thai BD patients and 192 healthy controls through next-generation sequencing using a PacBio kit. The study assessed 56 BD patients, primarily females (58.9%), revealing diverse manifestations including ocular (41.1%), vascular (35.7%), skin (55.4%), CNS (5.4%), and GI system (10.7%) involvement. This study found associations between BD and HLA-A*26:01:01 (OR 3.285, 95% CI 1.135-9.504, P-value 0.028), HLA-B*39:01:01 (OR 6.176, 95% CI 1.428-26.712, P-value 0.015), HLA-B*51:01:01 (OR 3.033, 95% CI 1.135-8.103, P-value 0.027), HLA-B*51:01:02 (OR 6.176, 95% CI 1.428-26.712, P-value 0.015), HLA-C*14:02:01 (OR 3.485, 95% CI 1.339-9.065, P-value 0.01), HLA-DRB1*14:54:01 (OR 1.924, 95% CI 1.051-3.522, P-value 0.034), and HLA-DQB1*05:03:01 (OR 3.00, 95% CI 1.323-6.798, P-value 0.008). However, after Bonferroni correction none of these alleles were found to be associated with BD. In haplotype analysis, we found a strong linkage disequilibrium in HLA-B*51:01:01, HLA-C*14:02:01 (P-value 0.0, Pc-value 0.02). Regarding the phenotype, a significant association was found between HLA-DRB1*14:54:01 (OR 11.67, 95% CI 2.86-47.57, P-value 0.001) and BD with ocular involvement, apart from this, no distinct phenotype-HLA association was documented. In summary, our study identifies specific HLA associations in BD. Although limited by a small sample size, we acknowledge the need for further investigation into HLA relationships with CNS, GI, and neurological phenotypes in the Thai population.


Asunto(s)
Síndrome de Behçet , Femenino , Humanos , Síndrome de Behçet/epidemiología , Cadenas HLA-DRB1/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Antígenos HLA-C/genética , Tailandia , Antígenos HLA-B/genética , Alelos , Tecnología , Predisposición Genética a la Enfermedad , Aminopeptidasas/genética , Antígenos de Histocompatibilidad Menor
4.
Nat Commun ; 15(1): 3301, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38671004

RESUMEN

Diphthamide is a modified histidine residue unique for eukaryotic translation elongation factor 2 (eEF2), a key ribosomal protein. Loss of this evolutionarily conserved modification causes developmental defects through unknown mechanisms. In a patient with compound heterozygous mutations in Diphthamide Biosynthesis 1 (DPH1) and impaired eEF2 diphthamide modification, we observe multiple defects in neural crest (NC)-derived tissues. Knockin mice harboring the patient's mutations and Xenopus embryos with Dph1 depleted also display NC defects, which can be attributed to reduced proliferation in the neuroepithelium. DPH1 depletion facilitates dissociation of eEF2 from ribosomes and association with p53 to promote transcription of the cell cycle inhibitor p21, resulting in inhibited proliferation. Knockout of one p21 allele rescues the NC phenotypes in the knockin mice carrying the patient's mutations. These findings uncover an unexpected role for eEF2 as a transcriptional coactivator for p53 to induce p21 expression and NC defects, which is regulated by diphthamide modification.


Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Histidina , Histidina/análogos & derivados , Antígenos de Histocompatibilidad Menor , Cresta Neural , Factor 2 de Elongación Peptídica , Proteína p53 Supresora de Tumor , Proteínas Supresoras de Tumor , Animales , Cresta Neural/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Humanos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Ratones , Factor 2 de Elongación Peptídica/metabolismo , Factor 2 de Elongación Peptídica/genética , Histidina/metabolismo , Ribosomas/metabolismo , Mutación , Proliferación Celular , Xenopus laevis , Femenino , Técnicas de Sustitución del Gen , Xenopus , Masculino , Ratones Noqueados
5.
Molecules ; 29(8)2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38675657

RESUMEN

Triple-negative breast cancer (TNBC) is a malignant breast cancer. There is an urgent need for effective drugs to be developed for TNBC. Tubocapsicum anomalum (T. anomalum) has been reported to have an anti-tumor effect, and six novel withanolides were isolated from it and designated as TAMEWs. However, its anti-TNBC effect is still unknown. The results of an MTT assay indicated a higher sensitivity of TNBC cells to TAMEWs compared to other cells. TAMEWs induced apoptosis via mitochondrial dysfunction. They caused increased levels of lipid ROS and Fe2+, with downregulation of GSH and cystine uptake, and it has been confirmed that TAMEWs induced ferroptosis. Additionally, the results of Western blotting indicate that TAMEWs significantly decrease the expressions of ferroptosis-related proteins. Through further investigation, it was found that the knockdown of the p53 gene resulted in a significant reversal of ferroptosis and the expressions of its associated proteins SLC7A11, ASCT2, and GPX4. In vivo, TAMEWs suppressed TNBC growth with no obvious damage. The IHC results also showed that TAMEWs induced apoptosis and ferroptosis in vivo. Our findings provide the first evidence that TAMEWs suppress TNBC growth through apoptosis and ferroptosis.


Asunto(s)
Sistema de Transporte de Aminoácidos y+ , Apoptosis , Ferroptosis , Neoplasias de la Mama Triple Negativas , Proteína p53 Supresora de Tumor , Witanólidos , Ferroptosis/efectos de los fármacos , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Humanos , Proteína p53 Supresora de Tumor/metabolismo , Proteína p53 Supresora de Tumor/genética , Witanólidos/farmacología , Witanólidos/química , Apoptosis/efectos de los fármacos , Femenino , Sistema de Transporte de Aminoácidos y+/metabolismo , Sistema de Transporte de Aminoácidos y+/genética , Animales , Línea Celular Tumoral , Ratones , Antígenos de Histocompatibilidad Menor/metabolismo , Antígenos de Histocompatibilidad Menor/genética , Especies Reactivas de Oxígeno/metabolismo , Proliferación Celular/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
6.
Front Immunol ; 15: 1346687, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38495872

RESUMEN

Introduction: Immunotherapy with biologics targeting programmed cell death protein-1 (PD-1) is highly effective in the treatment of various malignancies. Nevertheless, it is frequently responsible for unexpected cutaneous manifestations, including psoriasis-like dermatitis. The pathogenesis of anti-PD-1-induced psoriasis has yet to be clarified, even though it is plausible that some innate and adaptive immunity processes are in common with canonical psoriasis. The genetic predisposition to psoriasis of patients could also be a contributing factor. Here, we investigated the immunological and genetic profiles of two patients with metastatic melanoma and one patient affected by lung cancer, who developed severe psoriasis after receiving anti-PD-1 nivolumab therapy. Methods: The immune patterns of the three patients were compared with those detectable in classical, chronic plaque-type psoriasis or paradoxical psoriasis induced by anti-TNF-α therapy, mostly sustained by adaptive and innate immunity processes, respectively. Therefore, immunohistochemistry and mRNA analyses of innate and adaptive immunity molecules were conducted on skin biopsy of patients. Genetic analysis of polymorphisms predisposing to psoriasis was carried out by NGS technology. Results: We found that anti-PD-1-induced psoriasis showed immunological features similar to chronic psoriasis, characterized by the presence of cellular players of adaptive immunity, with abundant CD3+, CD8+ T cells and CD11c+ dendritic cells infiltrating skin lesions, and producing IL-23, IL-6, TNF-α, IFN-γ and IL-17. On the contrary, a lower number of innate immunity cells (BDCA2+ plasmacytoid dendritic cells, CD15+ neutrophils, CD117+ mast cells) and reduced IFN-α/ß, lymphotoxin (LT)-α/ß, were observed in anti-PD-1-induced psoriasis lesions, as compared with anti-TNF-α-induced paradoxical psoriasis. Importantly, the disintegrin and metalloprotease domain containing thrombospondin type 1 motif-like 5 (ADAMTSL5) psoriasis autoantigen was significantly upregulated in psoriasis lesions of anti-PD-1-treated patients, at levels comparable with chronic plaque-type psoriasis. Finally, NGS analysis revealed that all patients carried several allelic variants in psoriasis susceptibility genes, such as HLA-C, ERAP1 and other genes of the major psoriasis susceptibility PSORS1 locus. Discussion: Our study showed that adaptive immunity predominates over innate immunity in anti-PD-1-induced psoriasis lesions, consistently with the local ADAMTSL5 overexpression. The presence of numerous SNPs in psoriasis susceptibility genes of the three patients also suggested their strong predisposition to the disease.


Asunto(s)
Linfocitos T CD8-positivos , Psoriasis , Humanos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores del Factor de Necrosis Tumoral/uso terapéutico , Piel , Factor de Necrosis Tumoral alfa/metabolismo , Aminopeptidasas/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo , Proteínas ADAMTS
7.
Cancer Lett ; 588: 216727, 2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38431035

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) is a formidable cancer type that poses significant treatment challenges, including radiotherapy (RT) resistance. The metabolic characteristics of tumors present substantial obstacles to cancer therapy, and the relationship between RT and tumor metabolism in HNSCC remains elusive. Ferroptosis is a type of iron-dependent regulated cell death, representing an emerging disease-modulatory mechanism. Here, we report that after RT, glutamine levels rise in HNSCC, and the glutamine transporter protein SLC1A5 is upregulated. Notably, blocking glutamine significantly enhances the therapeutic efficacy of RT in HNSCC. Furthermore, inhibition of glutamine combined with RT triggers immunogenic tumor ferroptosis, a form of nonapoptotic regulated cell death. Mechanistically, RT increases interferon regulatory factor (IRF) 1 expression by activating the interferon signaling pathway, and glutamine blockade augments this efficacy. IRF1 drives transferrin receptor expression, elevating intracellular Fe2+ concentration, disrupting iron homeostasis, and inducing cancer cell ferroptosis. Importantly, the combination treatment-induced ferroptosis is dependent on IRF1 expression. Additionally, blocking glutamine combined with RT boosts CD47 expression and hinders macrophage phagocytosis, attenuating the treatment effect. Dual-blocking glutamine and CD47 promote tumor remission and enhance RT-induced ferroptosis, thereby ameliorating the tumor microenvironment. Our work provides valuable insights into the metabolic and immunological mechanisms underlying RT-induced ferroptosis, highlighting a promising strategy to augment RT efficacy in HNSCC.


Asunto(s)
Ferroptosis , Neoplasias de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Carcinoma de Células Escamosas de Cabeza y Cuello/radioterapia , Glutamina/metabolismo , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Antígeno CD47 , Línea Celular Tumoral , Hierro/metabolismo , Microambiente Tumoral , Antígenos de Histocompatibilidad Menor/metabolismo , Sistema de Transporte de Aminoácidos ASC/metabolismo
8.
J Immunother Cancer ; 12(3)2024 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-38519054

RESUMEN

Human leukocyte antigen (HLA) restriction of conventional T-cell targeting introduces complexity in generating T-cell therapy strategies for patients with cancer with diverse HLA-backgrounds. A subpopulation of atypical, major histocompatibility complex-I related protein 1 (MR1)-restricted T-cells, distinctive from mucosal-associated invariant T-cells (MAITs), was recently identified recognizing currently unidentified MR1-presented cancer-specific metabolites. It is hypothesized that the MC.7.G5 MR1T-clone has potential as a pan-cancer, pan-population T-cell immunotherapy approach. These cells are irresponsive to healthy tissue while conferring T-cell receptor(TCR) dependent, HLA-independent cytotoxicity to a wide range of adult cancers. Studies so far are limited to adult malignancies. Here, we investigated the potential of MR1-targeting cellular therapy strategies in pediatric cancer. Bulk RNA sequencing data of primary pediatric tumors were analyzed to assess MR1 expression. In vitro pediatric tumor models were subsequently screened to evaluate their susceptibility to engineered MC.7.G5 TCR-expressing T-cells. Targeting capacity was correlated with qPCR-based MR1 mRNA and protein overexpression. RNA expression of MR1 in primary pediatric tumors varied widely within and between tumor entities. Notably, embryonal tumors exhibited significantly lower MR1 expression than other pediatric tumors. In line with this, most screened embryonal tumors displayed resistance to MR1T-targeting in vitro MR1T susceptibility was observed particularly in pediatric leukemia and diffuse midline glioma models. This study demonstrates potential of MC.7.G5 MR1T-cell immunotherapy in pediatric leukemias and diffuse midline glioma, while activity against embryonal tumors was limited. The dismal prognosis associated with relapsed/refractory leukemias and high-grade brain tumors highlights the promise to improve survival rates of children with these cancers.


Asunto(s)
Glioma , Leucemia , Neoplasias de Células Germinales y Embrionarias , Humanos , Niño , Antígenos de Histocompatibilidad Clase I , Receptores de Antígenos de Linfocitos T , Antígenos de Histocompatibilidad Clase II , Antígenos de Histocompatibilidad Menor
9.
J Hepatol ; 80(2): 293-308, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38450598

RESUMEN

BACKGROUND & AIMS: The role of solute carrier family 25 member 15 (SLC25A15), a critical component of the urea cycle, in hepatocellular carcinoma (HCC) progression remains poorly understood. This study investigated the impact of SLC25A15 on HCC progression and its mechanisms. METHODS: We systematically investigated the function of SLC25A15 in HCC progression using large-scale data mining and cell, animal, and organoid models. Furthermore, we analyzed its involvement in reprogramming glutamine metabolism. RESULTS: SLC25A15 expression was significantly decreased in HCC tissues, and patients with low SLC25A15 levels had a poorer prognosis. Hypoxia-exposed HCC cells or tissues had lower SLC25A15 expression. A positive correlation between HNF4A, a transcription factor suppressed by hypoxia, and SLC25A15 was observed in both HCC tissues and cells. Modulating HNF4A levels altered SLC25A15 mRNA levels. SLC25A15 upregulated SLC1A5, increasing glutamine uptake. The reactive metabolic pathway of glutamine was increased in SLC25A15-deficient HCC cells, providing energy for HCC progression through additional lipid synthesis. Ammonia accumulation due to low SLC25A15 levels suppressed the expression of OGDHL (oxoglutarate dehydrogenase L), a switch gene that mediates SLC25A15 deficiency-induced reprogramming of glutamine metabolism. SLC25A15-deficient HCC cells were more susceptible to glutamine deprivation and glutaminase inhibitors. Intervening in glutamine metabolism increased SLC25A15-deficient HCC cells' response to anti-PD-L1 treatment. CONCLUSION: SLC25A15 is hypoxia-responsive in HCC, and low SLC25A15 levels result in glutamine reprogramming through SLC1A5 and OGDHL regulation, promoting HCC progression and regulating cell sensitivity to anti-PD-L1. Interrupting the glutamine-derived energy supply is a potential therapeutic strategy for treating SLC25A15-deficient HCC. IMPACT AND IMPLICATIONS: We first demonstrated the tumor suppressor role of solute carrier family 25 member 15 (SLC25A15) in hepatocellular carcinoma (HCC) and showed that its deficiency leads to reprogramming of glutamine metabolism to promote HCC development. SLC25A15 can serve as a potential biomarker to guide the development of precision therapeutic strategies aimed at targeting glutamine deprivation. Furthermore, we highlight that the use of an inhibitor of glutamine utilization can enhance the sensitivity of low SLC25A15 HCC to anti-PD-L1 therapy.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Humanos , Carcinoma Hepatocelular/genética , Glutamina , Neoplasias Hepáticas/genética , Hipoxia/genética , Transporte Biológico , Antígenos de Histocompatibilidad Menor , Sistema de Transporte de Aminoácidos ASC/genética
10.
Brain Behav ; 14(3): e3465, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38468469

RESUMEN

BACKGROUND: SP gene family, consisting of SP100, SP110, SP140, and SP140L, has been implicated in the initiation and advancement of numerous malignancies. Nevertheless, their clinical significance in glioma remains incompletely understood. METHOD: Expression levels and prognostic significance of SP family members were evaluated in the TCGA and CGGA datasets. Multifactorial analysis was used to identify SP gene family members that can independently impact the prognosis of glioma patients. A SP140-based predictive risk model/nomogram was developed in TCGA dataset and validated in CGGA dataset. The model's performance was evaluated through receiver operating characteristic (ROC) curves, calibration plots, and decision curve analyses. Phenotypic associations of SP140 and TRIM22 were examined through CancerSEA and TIMER. The effect of SP140 inhibitor in glioma progress and TRIM22/PI3K/AKT signaling pathway was confirmed in U251/U87 glioma cells. RESULTS: The SP family members exhibited elevated expression in gliomas and were negatively correlated with prognosis. SP140 emerged as an independent prognostic factor, and a SP140-based nomogram/predictive risk model demonstrated high accuracy. SP140 inhibitor, GSK761, lead to the suppression of TRIM22 expression and the PI3K/AKT signaling pathway. GSK761 also restrain glioma proliferation, migration, and invasion. Furthermore, SP140 and TRIM22 coexpressed in glioma cells with high level of vascular proliferation, TRIM22 is closely associated with the immune cell infiltration. CONCLUSION: SP140-based nomogram proved to be a practical tool for predicting the survival of glioma patients. SP140 inhibitor could suppress glioma progress via TRIM22/PI3K/AKT signaling pathway.


Asunto(s)
Glioma , Proteínas Proto-Oncogénicas c-akt , Humanos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proliferación Celular , Transducción de Señal , Glioma/tratamiento farmacológico , Glioma/genética , Proteínas de Motivos Tripartitos/genética , Proteínas de Motivos Tripartitos/farmacología , Proteínas Represoras/metabolismo , Antígenos de Histocompatibilidad Menor/farmacología , Factores de Transcripción , Antígenos Nucleares/metabolismo , Antígenos Nucleares/farmacología
11.
Nat Commun ; 15(1): 2370, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499542

RESUMEN

Antiviral DNA cytosine deaminases APOBEC3A and APOBEC3B are major sources of mutations in cancer by catalyzing cytosine-to-uracil deamination. APOBEC3A preferentially targets single-stranded DNAs, with a noted affinity for DNA regions that adopt stem-loop secondary structures. However, the detailed substrate preferences of APOBEC3A and APOBEC3B have not been fully established, and the specific influence of the DNA sequence on APOBEC3A and APOBEC3B deaminase activity remains to be investigated. Here, we find that APOBEC3B also selectively targets DNA stem-loop structures, and they are distinct from those subjected to deamination by APOBEC3A. We develop Oligo-seq, an in vitro sequencing-based method to identify specific sequence contexts promoting APOBEC3A and APOBEC3B activity. Through this approach, we demonstrate that APOBEC3A and APOBEC3B deaminase activity is strongly regulated by specific sequences surrounding the targeted cytosine. Moreover, we identify the structural features of APOBEC3B and APOBEC3A responsible for their substrate preferences. Importantly, we determine that APOBEC3B-induced mutations in hairpin-forming sequences within tumor genomes differ from the DNA stem-loop sequences mutated by APOBEC3A. Together, our study provides evidence that APOBEC3A and APOBEC3B can generate distinct mutation landscapes in cancer genomes, driven by their unique substrate selectivity.


Asunto(s)
Neoplasias , Proteínas , Humanos , Mutación , Neoplasias/genética , Citidina Desaminasa/genética , Citidina Desaminasa/química , ADN , Antígenos de Histocompatibilidad Menor/genética , Antígenos de Histocompatibilidad Menor/química , Citosina
12.
Nat Commun ; 15(1): 2369, 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38499553

RESUMEN

The APOBEC3 enzymes convert cytosines in single-stranded DNA to uracils to protect against viruses and retrotransposons but can contribute to mutations that diversify tumors. To understand the mechanism of mutagenesis, we map the uracils resulting from expression of APOBEC3B or its catalytic carboxy-terminal domain (CTD) in Escherichia coli. Like APOBEC3A, the uracilomes of A3B and A3B-CTD show a preference to deaminate cytosines near transcription start sites and the lagging-strand replication templates and in hairpin loops. Both biochemical activities of the enzymes and genomic uracil distribution show that A3A prefers 3 nt loops the best, while A3B prefers 4 nt loops. Reanalysis of hairpin loop mutations in human tumors finds intrinsic characteristics of both the enzymes, with a much stronger contribution from A3A. We apply Hairpin Signatures 1 and 2, which define A3A and A3B preferences respectively and are orthogonal to published methods, to evaluate their contribution to human tumor mutations.


Asunto(s)
Citosina , Neoplasias , Humanos , Citosina/metabolismo , Proteínas/metabolismo , Mutación , Citidina Desaminasa/metabolismo , Neoplasias/genética , Uracilo/metabolismo , Antígenos de Histocompatibilidad Menor/metabolismo
13.
Mol Biol Rep ; 51(1): 462, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38551779

RESUMEN

BACKGROUND: Ankylosing spondylitis (AS) is a chronic and systemic seronegative inflammatory spondyloarthropathy, an autoimmune disease that has been associated with impaired Endoplasmic Reticulum Aminopeptidase (ERAP)-1 activity, which is involved in priming antigenic peptides. The purpose of this study is to investigate the association of 3-UTR of ERAP1 gene polymorphism (rs13167972) with the AS occurrence susceptibility in a sample of Iraqi male patients. METHODS: The AS patients were diagnosed clinically and by magnetic resonance imaging (MRI) and other clinical and laboratory criteria like symptoms, increased C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR). The blood grouping and Body Mass Index (BMI) were also investigated to be associated with AS occurrence. The genotyping of the 3-UTR region of the ERAP1 gene (rs13167972) was done by Sanger sequencing. RESULTS: The results revealed that the AS occurred significantly in the age group of 20-35 years (p = 0.013). The BMI shows that the AS patients were overweighted males (p = 0.013) and the most predominant blood group in AS patients was O- (p = 0.002). The ESR and serum level of CRP were significantly raised in AS patient sera (< 0.001). The results of the receiver-operating characteristics curve analysis (ROC) revealed that the CRP (AUC: 0.995, cut-off: 2.48 mg/L, had 95% %sensitivity, 100% specificity, p < 0.001) is more discriminative than BMI (AUC: 0.300, cut-off: 46.91 kg, had 0% sensitivity, 100% specificity, p = 0.001), and ESR (AUC: 0.808, cut-off: 7.50 mm/hr, had 60% sensitivity, 88% specificity, p < 0.001) in distinguishing between AS patients and control group. The genotyping of the 3-UTR region of ERAP1 gene (rs13167972) result shows that the AG and GG genotypes are significantly occurring in AS patients (70%, OR: 2.33, 95%CI: 1.02-5.36, p = 0.04). The G allele is significantly occurring in AS patients (47%, OR: 2.07, 95CI%: 1.15-3.71, p = 0.01). CONCLUSION: The AS occurred in young overweight males with blood group O-. The AG and GG genotypes are risk factors for AS development while the G allele is a risk factor that increases the chances for disease incidence.


Asunto(s)
Antígenos de Grupos Sanguíneos , Espondilitis Anquilosante , Humanos , Masculino , Adulto Joven , Adulto , Espondilitis Anquilosante/diagnóstico , Irak/epidemiología , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Aminopeptidasas/genética , Retículo Endoplásmico , Antígenos de Histocompatibilidad Menor/genética
14.
Cell Rep ; 43(4): 113992, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38536815

RESUMEN

Insulin is packaged into secretory granules that depart the Golgi and undergo a maturation process that involves changes in the protein and lipid composition of the granules. Here, we show that insulin secretory granules form physical contacts with the endoplasmic reticulum and that the lipid exchange protein oxysterol-binding protein (OSBP) is recruited to these sites in a Ca2+-dependent manner. OSBP binding to insulin granules is positively regulated by phosphatidylinositol-4 (PI4)-kinases and negatively regulated by the PI4 phosphate (PI(4)P) phosphatase Sac2. Loss of Sac2 results in excess accumulation of cholesterol on insulin granules that is normalized when OSBP expression is reduced, and both acute inhibition and small interfering RNA (siRNA)-mediated knockdown of OSBP suppress glucose-stimulated insulin secretion without affecting insulin production or intracellular Ca2+ signaling. In conclusion, we show that lipid exchange at endoplasmic reticulum (ER)-granule contact sites is involved in the exocytic process and propose that these contacts act as reaction centers with multimodal functions during insulin granule maturation.


Asunto(s)
Colesterol , Retículo Endoplásmico , Secreción de Insulina , Insulina , Antígenos de Histocompatibilidad Menor , Receptores de Esteroides , Vesículas Secretoras , Retículo Endoplásmico/metabolismo , Vesículas Secretoras/metabolismo , Animales , Colesterol/metabolismo , Insulina/metabolismo , Receptores de Esteroides/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Ratones , Humanos , Calcio/metabolismo , Fosfotransferasas (Aceptor de Grupo Alcohol)/metabolismo , Glucosa/metabolismo
15.
Blood ; 143(18): 1856-1872, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38427583

RESUMEN

ABSTRACT: Allogeneic stem cell transplantation (alloSCT) is a curative treatment for hematological malignancies. After HLA-matched alloSCT, antitumor immunity is caused by donor T cells recognizing polymorphic peptides, designated minor histocompatibility antigens (MiHAs), that are presented by HLA on malignant patient cells. However, T cells often target MiHAs on healthy nonhematopoietic tissues of patients, thereby inducing side effects known as graft-versus-host disease. Here, we aimed to identify the dominant repertoire of HLA-I-restricted MiHAs to enable strategies to predict, monitor or modulate immune responses after alloSCT. To systematically identify novel MiHAs by genome-wide association screening, T-cell clones were isolated from 39 transplanted patients and tested for reactivity against 191 Epstein-Barr virus transformed B cell lines of the 1000 Genomes Project. By discovering 81 new MiHAs, we more than doubled the antigen repertoire to 159 MiHAs and demonstrated that, despite many genetic differences between patients and donors, often the same MiHAs are targeted in multiple patients. Furthermore, we showed that one quarter of the antigens are cryptic, that is translated from unconventional open reading frames, for example long noncoding RNAs, showing that these antigen types are relevant targets in natural immune responses. Finally, using single cell RNA-seq data, we analyzed tissue expression of MiHA-encoding genes to explore their potential role in clinical outcome, and characterized 11 new hematopoietic-restricted MiHAs as potential targets for immunotherapy. In conclusion, we expanded the repertoire of HLA-I-restricted MiHAs and identified recurrent, cryptic and hematopoietic-restricted antigens, which are fundamental to predict, follow or manipulate immune responses to improve clinical outcome after alloSCT.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Antígenos de Histocompatibilidad Clase I , Antígenos de Histocompatibilidad Menor , Humanos , Antígenos de Histocompatibilidad Menor/genética , Antígenos de Histocompatibilidad Menor/inmunología , Antígenos de Histocompatibilidad Clase I/inmunología , Antígenos de Histocompatibilidad Clase I/genética , Neoplasias Hematológicas/inmunología , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/genética , Linfocitos T/inmunología , Estudio de Asociación del Genoma Completo , Trasplante Homólogo , Femenino , Masculino
16.
J Exp Clin Cancer Res ; 43(1): 44, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-38326863

RESUMEN

BACKGROUND: m6A modification is currently recognized as a major driver of RNA function that maintains cancer cell homeostasis. Long non-coding (Lnc) RNAs control cell proliferation and play an important role in the occurrence and progression of colorectal cancer (CRC). ZCCHC4 is a newly discovered m6A methyltransferase whose role and mechanism in tumors have not yet been elucidated. METHODS: The EpiQuik m6A RNA methylation kit was used to detect the level of total RNA m6A in six types of digestive tract tumors. The Kaplan-Meier method and receiver operating characteristic curve were used to evaluate the prognostic and diagnostic value of the newly discovered m6A methyltransferase, ZCCHC4, in CRC. The effects on CRC growth in vitro and in vivo were studied using gain- and loss-of-function experiments. The epigenetic mechanisms underlying ZCCHC4 upregulation in CRC were studied using RIP, MeRIP-seq, RNA pull-down, and animal experiments. RESULTS: We reported that the ZCCHC4-LncRNAGHRLOS-KDM5D axis regulates the growth of CRC in vitro and in vivo. We found that ZCCHC4 was upregulated in primary CRC samples and could predict adverse clinical outcomes in patients with CRC. Mechanistically, ZCCHC4 downregulated LncRNAGHRLOS to promote CRC tumorigenesis. As a downstream molecule of LncRNAGHRLOS, KDM5D directly controls CRC cell proliferation, migration, and invasion. CONCLUSION: This study suggests that the ZCCHC4 axis contributes to the tumorigenesis and progression of CRC and that ZCCHC4 may be a potential biomarker for this malignancy.


Asunto(s)
Adenina , Neoplasias Colorrectales , ARN Largo no Codificante , Animales , Humanos , Adenina/análogos & derivados , Carcinogénesis/genética , Línea Celular Tumoral , Transformación Celular Neoplásica/genética , Neoplasias Colorrectales/patología , Regulación hacia Abajo , Epigénesis Genética , Histona Demetilasas/genética , Metiltransferasas/metabolismo , Antígenos de Histocompatibilidad Menor , ARN , ARN Largo no Codificante/genética , ARNt Metiltransferasas/genética , ARNt Metiltransferasas/metabolismo
17.
Ann Surg Oncol ; 31(5): 3087-3097, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38347332

RESUMEN

INTRODUCTION: Data on clinical characteristics and disease-specific prognosis among patients with early onset intrahepatic cholangiocarcinoma (ICC) are currently limited. METHODS: Patients undergoing hepatectomy for ICC between 2000 and 2020 were identified by using a multi-institutional database. The association of early (≤50 years) versus typical onset (>50 years) ICC with recurrence-free (RFS) and disease-specific survival (DSS) was assessed in the multi-institutional database and validated in an external cohort. The genomic and transcriptomic profiles of early versus late onset ICC were analyzed by using the Total Cancer Genome Atlas (TCGA) and Memorial Sloan Kettering Cancer Center databases. RESULTS: Among 971 patients undergoing resection for ICC, 22.7% (n = 220) had early-onset ICC. Patients with early-onset ICC had worse 5-year RFS (24.1% vs. 29.7%, p < 0.05) and DSS (36.5% vs. 48.9%, p = 0.03) compared with patients with typical onset ICC despite having earlier T-stage tumors and lower rates of microvascular invasion. In the validation cohort, patients with early-onset ICC had worse 5-year RFS (7.4% vs. 20.5%, p = 0.002) compared with individuals with typical onset ICC. Using the TCGA cohort, 652 and 266 genes were found to be upregulated (including ATP8A2) and downregulated (including UTY and KDM5D) in early versus typical onset ICC, respectively. Genes frequently implicated as oncogenic drivers, including CDKN2A, IDH1, BRAF, and FGFR2 were infrequently mutated in the early-onset ICC patients. CONCLUSIONS: Early-onset ICC has distinct clinical and genomic/transcriptomic features. Morphologic and clinicopathologic characteristics were unable to fully explain differences in outcomes among early versus typical onset ICC patients. The current study offers a preliminary landscape of the molecular features of early-onset ICC.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Humanos , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/cirugía , Colangiocarcinoma/genética , Colangiocarcinoma/cirugía , Pronóstico , Perfilación de la Expresión Génica , Hepatectomía , Genómica , Conductos Biliares Intrahepáticos/patología , Antígenos de Histocompatibilidad Menor , Histona Demetilasas
18.
Arch Med Res ; 55(3): 102970, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38401326

RESUMEN

BACKGROUND: The relationship between GEMIN4 genetic variants and cancer, especially bladder carcinoma (BLCA), has been explored without conclusive results. This study aims to elucidate the link between GEMIN4 polymorphisms and BLCA susceptibility through genetic analyses, bioinformatics, and molecular dynamics (MD) simulations. METHODS: A cohort of 249 participants (121 BLCA patients and 128 unrelated controls) was enrolled. PCR was employed for allelic discrimination of GEMIN4 variants, followed by subgroup stratification, haplotype analyses, structural prediction using the AlphaFold2 prediction tool, subsequent MD simulations, structural analysis, and residue interaction mapping using Desmond, UCSF ChimeraX, and Cytoscape softwares. RESULTS: The rs.2740348*G variant demonstrated a protective role against BLCA in allelic (OR = 0.55, p = 0.002) and recessive (OR = 0.54, p = 0.017) models, whereas the rs.7813*T variant increased BLCA risk under the recessive model (OR = 1.90, p = 0.019). Haplotype analysis revealed a significant association between GEMIN4 haplotype (rs.2740348*C/rs.7813*T) with increased BLCA risk (OR = 2.01, p = 0.004). Univariate analysis revealed associations of the variants with albumin levels and absolute neutrophil count in BLCA patients. Pathogenicity evaluation categorized p.Gln450Glu as neutral and p.Arg1033Cys as deleterious. MD simulations revealed structural alterations and conformational shifts in the GEMIN4 protein induced by the Glu450 and Cys1033 mutations. CONCLUSIONS: The study highlights the dual role of GEMIN4 variants in BLCA susceptibility, with rs.2740348 conferring protection and rs.7813 increasing risk. The Glu450 residue positively impacted protein stability, while Cys1033 had a detrimental effect on protein function. These findings underscore the significance of GEMIN4 variants in BLCA susceptibility and pave the way for future diagnostic and therapeutic initiatives.


Asunto(s)
Carcinoma , Neoplasias de la Vejiga Urinaria , Humanos , Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/genética , Biología Computacional , Alelos , Antígenos de Histocompatibilidad Menor , Ribonucleoproteínas Nucleares Pequeñas
19.
Angew Chem Int Ed Engl ; 63(16): e202400637, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38409519

RESUMEN

Abnormal physiological processes and diseases can lead to content or activity fluctuations of biocomponents in organelles and whole blood. However, precise monitoring of these abnormalities remains extremely challenging due to the insufficient sensitivity and accuracy of available fluorescence probes, which can be attributed to the background fluorescence arising from two sources, 1) biocomponent autofluorescence (BCAF) and 2) probe intrinsic fluorescence (PIF). To overcome these obstacles, we have re-engineered far-red to NIR II rhodol derivatives that possess weak BCAF interference. And a series of "zero" PIF sensing-platforms were created by systematically regulating the open-loop/spirocyclic forms. Leveraging these advancements, we devised various ultra-sensitive NIR indicators, achieving substantial fluorescence boosts (190 to 1300-fold). Among these indicators, 8-LAP demonstrated accurate tracking and quantifying of leucine aminopeptidase (LAP) in whole blood at various stages of tumor metastasis. Furthermore, coupling 8-LAP with an endoplasmic reticulum-targeting element enabled the detection of ERAP1 activity in HCT116 cells with p53 abnormalities. This delicate design of eliminating PIF provides insights into enhancing the sensitivity and accuracy of existing fluorescence probes toward the detection and imaging of biocomponents in abnormal physiological processes and diseases.


Asunto(s)
Leucil Aminopeptidasa , Imagen Óptica , Humanos , Fluorescencia , Microscopía Fluorescente/métodos , Retículo Endoplásmico , Espectrometría de Fluorescencia/métodos , Colorantes Fluorescentes , Aminopeptidasas , Antígenos de Histocompatibilidad Menor
20.
Eur Rev Med Pharmacol Sci ; 28(2): 463-468, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38305593

RESUMEN

OBJECTIVE: The aim of this study was to screen the differential genes related to ferroptosis in osteoporosis patients. MATERIALS AND METHODS: GEO2R was used to screen the differential genes related to ferroptosis in osteoporosis patients by searching the relevant chips in the GEO database, and Spearman's correlation analysis was used to describe the correlation between quantitative variables without normal distribution. p-values lower than 0.05 were considered statistically significant. Another group of osteoporosis patients was selected in the GEO database to verify the significantly differentially expressed genes. RESULTS: The results showed that 10 samples in chip GSE35956 were identified as research objects, and a total of 5 ferroptosis differential genes were screened out: ATP5MC3, CDKN1A, MT1G, NCOA4, SLC1A5, of which 3 up-regulated genes (CDKN1A, MT1G, SLC1A5), 2 down-regulated genes (ATP5MC3, NCOA4). The above differential genes were placed in 19 samples of chip GSE35959 for verification, and the same expression trend was obtained, but only the MT1G difference was statistically significant. CONCLUSIONS: The gene correlation test found that MT1G and ATP5MC3 had a strong negative correlation.


Asunto(s)
Ferroptosis , Osteoporosis , Humanos , Ferroptosis/genética , Bases de Datos Factuales , Expresión Génica , Osteoporosis/genética , Valores de Referencia , Antígenos de Histocompatibilidad Menor , Sistema de Transporte de Aminoácidos ASC
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