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1.
Mol Cell ; 84(18): 3513-3529.e5, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39255795

RESUMO

Innate immunity serves as the primary defense against viral and microbial infections in humans. The precise influence of cellular metabolites, especially fatty acids, on antiviral innate immunity remains largely elusive. Here, through screening a metabolite library, palmitic acid (PA) has been identified as a key modulator of antiviral infections in human cells. Mechanistically, PA induces mitochondrial antiviral signaling protein (MAVS) palmitoylation, aggregation, and subsequent activation, thereby enhancing the innate immune response. The palmitoyl-transferase ZDHHC24 catalyzes MAVS palmitoylation, thereby boosting the TBK1-IRF3-interferon (IFN) pathway, particularly under conditions of PA stimulation or high-fat-diet-fed mouse models, leading to antiviral immune responses. Additionally, APT2 de-palmitoylates MAVS, thus inhibiting antiviral signaling, suggesting that its inhibitors, such as ML349, effectively reverse MAVS activation in response to antiviral infections. These findings underscore the critical role of PA in regulating antiviral innate immunity through MAVS palmitoylation and provide strategies for enhancing PA intake or targeting APT2 for combating viral infections.


Assuntos
Aciltransferases , Proteínas Adaptadoras de Transdução de Sinal , Imunidade Inata , Fator Regulador 3 de Interferon , Lipoilação , Ácido Palmítico , Transdução de Sinais , Imunidade Inata/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/imunologia , Humanos , Animais , Ácido Palmítico/farmacologia , Camundongos , Células HEK293 , Fator Regulador 3 de Interferon/metabolismo , Fator Regulador 3 de Interferon/genética , Fator Regulador 3 de Interferon/imunologia , Aciltransferases/genética , Aciltransferases/imunologia , Aciltransferases/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Camundongos Endogâmicos C57BL , Antivirais/farmacologia , Proteínas de Neoplasias , Peptídeos e Proteínas de Sinalização Intracelular
2.
Immunity ; 54(9): 2117-2132.e7, 2021 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-34525340

RESUMO

The nature of the anti-tumor immune response changes as primary tumors progress and metastasize. We investigated the role of resident memory (Trm) and circulating memory (Tcirm) cells in anti-tumor responses at metastatic locations using a mouse model of melanoma-associated vitiligo. We found that the transcriptional characteristics of tumor-specific CD8+ T cells were defined by the tissue of occupancy. Parabiosis revealed that tumor-specific Trm and Tcirm compartments persisted throughout visceral organs, but Trm cells dominated lymph nodes (LNs). Single-cell RNA-sequencing profiles of Trm cells in LN and skin were distinct, and T cell clonotypes that occupied both tissues were overwhelmingly maintained as Trm in LNs. Whereas Tcirm cells prevented melanoma growth in the lungs, Trm afforded long-lived protection against melanoma seeding in LNs. Expanded Trm populations were also present in melanoma-involved LNs from patients, and their transcriptional signature predicted better survival. Thus, tumor-specific Trm cells persist in LNs, restricting metastatic cancer.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Linfonodos/imunologia , Melanoma Experimental/imunologia , Melanoma/imunologia , Neoplasias Cutâneas/imunologia , Animais , Humanos , Camundongos , Vitiligo , Melanoma Maligno Cutâneo
3.
Nature ; 593(7858): 211-217, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33981050

RESUMO

Advanced beyond-silicon electronic technology requires both channel materials and also ultralow-resistance contacts to be discovered1,2. Atomically thin two-dimensional semiconductors have great potential for realizing high-performance electronic devices1,3. However, owing to metal-induced gap states (MIGS)4-7, energy barriers at the metal-semiconductor interface-which fundamentally lead to high contact resistance and poor current-delivery capability-have constrained the improvement of two-dimensional semiconductor transistors so far2,8,9. Here we report ohmic contact between semimetallic bismuth and semiconducting monolayer transition metal dichalcogenides (TMDs) where the MIGS are sufficiently suppressed and degenerate states in the TMD are spontaneously formed in contact with bismuth. Through this approach, we achieve zero Schottky barrier height, a contact resistance of 123 ohm micrometres and an on-state current density of 1,135 microamps per micrometre on monolayer MoS2; these two values are, to the best of our knowledge, the lowest and highest yet recorded, respectively. We also demonstrate that excellent ohmic contacts can be formed on various monolayer semiconductors, including MoS2, WS2 and WSe2. Our reported contact resistances are a substantial improvement for two-dimensional semiconductors, and approach the quantum limit. This technology unveils the potential of high-performance monolayer transistors that are on par with state-of-the-art three-dimensional semiconductors, enabling further device downscaling and extending Moore's law.

4.
J Cell Sci ; 136(22)2023 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-37902010

RESUMO

The contractile vacuole complex (CVC) is a dynamic and morphologically complex membrane organelle, comprising a large vesicle (bladder) linked with a tubular reticulum (spongiome). CVCs provide key osmoregulatory roles across diverse eukaryotic lineages, but probing the mechanisms underlying their structure and function is hampered by the limited tools available for in vivo analysis. In the experimentally tractable ciliate Tetrahymena thermophila, we describe four proteins that, as endogenously tagged constructs, localize specifically to distinct CVC zones. The DOPEY homolog Dop1p and the CORVET subunit Vps8Dp localize both to the bladder and spongiome but with different local distributions that are sensitive to osmotic perturbation, whereas the lipid scramblase Scr7p colocalizes with Vps8Dp. The H+-ATPase subunit Vma4 is spongiome specific. The live imaging permitted by these probes revealed dynamics at multiple scales including rapid exchange of CVC-localized and soluble protein pools versus lateral diffusion in the spongiome, spongiome extension and branching, and CVC formation during mitosis. Although the association with DOP1 and VPS8D implicate the CVC in endosomal trafficking, both the bladder and spongiome might be isolated from bulk endocytic input.


Assuntos
Tetrahymena thermophila , Vacúolos , Vacúolos/metabolismo , Endossomos , Proteínas/metabolismo , Mitose
5.
PLoS Genet ; 18(5): e1010194, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35587496

RESUMO

In the ciliate Tetrahymena thermophila, lysosome-related organelles called mucocysts accumulate at the cell periphery where they secrete their contents in response to extracellular events, a phenomenon called regulated exocytosis. The molecular bases underlying regulated exocytosis have been extensively described in animals but it is not clear whether similar mechanisms exist in ciliates or their sister lineage, the Apicomplexan parasites, which together belong to the ecologically and medically important superphylum Alveolata. Beginning with a T. thermophila mutant in mucocyst exocytosis, we used a forward genetic approach to uncover MDL1 (Mucocyst Discharge with a LamG domain), a novel gene that is essential for regulated exocytosis of mucocysts. Mdl1p is a 40 kDa membrane glycoprotein that localizes to mucocysts, and specifically to a tip domain that contacts the plasma membrane when the mucocyst is docked. This sub-localization of Mdl1p, which occurs prior to docking, underscores a functional asymmetry in mucocysts that is strikingly similar to that of highly polarized secretory organelles in other Alveolates. A mis-sense mutation in the LamG domain results in mucocysts that dock but only undergo inefficient exocytosis. In contrast, complete knockout of MDL1 largely prevents mucocyst docking itself. Mdl1p is physically associated with 9 other proteins, all of them novel and largely restricted to Alveolates, and sedimentation analysis supports the idea that they form a large complex. Analysis of three other members of this putative complex, called MDD (for Mucocyst Docking and Discharge), shows that they also localize to mucocysts. Negative staining of purified MDD complexes revealed distinct particles with a central channel. Our results uncover a novel macromolecular complex whose subunits are conserved within alveolates but not in other lineages, that is essential for regulated exocytosis in T. thermophila.


Assuntos
Tetrahymena thermophila , Tetrahymena , Animais , Exocitose/genética , Lisossomos/metabolismo , Organelas/metabolismo , Vesículas Secretórias/genética , Vesículas Secretórias/metabolismo , Tetrahymena thermophila/genética
6.
PLoS Genet ; 18(4): e1010137, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35421082

RESUMO

Viral infections can alter host transcriptomes by manipulating host splicing machinery. Despite intensive transcriptomic studies on SARS-CoV-2, a systematic analysis of alternative splicing (AS) in severe COVID-19 patients remains largely elusive. Here we integrated proteomic and transcriptomic sequencing data to study AS changes in COVID-19 patients. We discovered that RNA splicing is among the major down-regulated proteomic signatures in COVID-19 patients. The transcriptome analysis showed that SARS-CoV-2 infection induces widespread dysregulation of transcript usage and expression, affecting blood coagulation, neutrophil activation, and cytokine production. Notably, CD74 and LRRFIP1 had increased skipping of an exon in COVID-19 patients that disrupts a functional domain, which correlated with reduced antiviral immunity. Furthermore, the dysregulation of transcripts was strongly correlated with clinical severity of COVID-19, and splice-variants may contribute to unexpected therapeutic activity. In summary, our data highlight that a better understanding of the AS landscape may aid in COVID-19 diagnosis and therapy.


Assuntos
COVID-19 , Processamento Alternativo/genética , COVID-19/genética , Teste para COVID-19 , Humanos , Proteômica , SARS-CoV-2/genética , Transcriptoma
7.
Genomics ; 116(5): 110917, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147335

RESUMO

Alternative splicing (AS) has significant clinical relevance with cancers and is a potential source of neoepitopes. In this study, RNA-seq data of 94 solid tumor and matched adjacent normal tissues from 47 clinical patients covering nine cancer types were comprehensively analyzed using SUVA developed by ourselves. The results identified highly conserved pan-cancer differential alternative splicing (DAS) events and cancer-specific DAS events in a series of tumor samples, which in turn revealed the heterogeneity of AS post-transcriptional regulation across different cancers. The co-disturbed network between spliceosome factors (SFs) and common cancer-associated DAS was further constructed, suggesting the potential possibility of the regulation of differentially expressed SFs on DAS. Finally, the common cancer-associated DAS events were fully validated using the TCGA dataset, confirming the significant correlation between cancer-associated DAS and prognosis. Briefly, our study elucidates new insights into conservatived and specific DAS in cancer, providing valuable resources for cancer therapeutic targets.


Assuntos
Processamento Alternativo , Neoplasias , Humanos , Neoplasias/genética , Spliceossomos/metabolismo , Spliceossomos/genética
8.
Nano Lett ; 24(29): 8880-8886, 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-38981026

RESUMO

We develop a novel metal contact approach using an antimony (Sb)-platinum (Pt) bilayer to mitigate Fermi-level pinning in 2D transition metal dichalcogenide channels. This strategy allows for control over the transport polarity in monolayer WSe2 devices. By adjustment of the Sb interfacial layer thickness from 10 to 30 nm, the effective work function of the contact/WSe2 interface can be tuned from 4.42 eV (p-type) to 4.19 eV (n-type), enabling selectable n-/p-FET operation in enhancement mode. The shift in effective work function is linked to Sb-Se bond formation and an emerging n-doping effect. This work demonstrates high-performance n- and p-FETs with a single WSe2 channel through Sb-Pt contact modulation. After oxide encapsulation, the maximum current density at |VD| = 1 V reaches 170 µA/µm for p-FET and 165 µA/µm for n-FET. This approach shows promise for cost-effective CMOS transistor applications using a single channel material and metal contact scheme.

9.
Nano Lett ; 24(22): 6465-6473, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38767853

RESUMO

Neutrophilic superhalide-anion-triggered chalcogen conversion-based Zn batteries, despite latent high-energy merit, usually suffer from a short lifespan caused by dendrite growth and shuttle effect. Here, a superhalide-anion-motivator reforming strategy is initiated to simultaneously manipulate the anode interface and Se conversion intermediates, realizing a bipolar regulation toward longevous energy-type Zn batteries. With ZnF2 chaotropic additives, the original large-radii superhalide zincate anion species in ionic liquid (IL) electrolytes are split into small F-containing species, boosting the formation of robust solid electrolyte interphases (SEI) for Zn dendrite inhibition. Simultaneously, ion radius reduced multiple F-containing Se conversion intermediates form, enhancing the interion interaction of charged products to suppress the shuttle effect. Consequently, Zn||Se batteries deliver a ca. 20-fold prolonged lifespan (2000 cycles) at 1 A g-1 and high energy/power density of 416.7 Wh kgSe-1/1.89 kW kgSe-1, outperforming those in F-free counterparts. Pouch cells with distinct plateaus and durable cyclability further substantiate the practicality of this design.

10.
Plant Mol Biol ; 114(3): 36, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598012

RESUMO

Increasing evidence indicates a strong correlation between the deposition of cuticular waxes and drought tolerance. However, the precise regulatory mechanism remains elusive. Here, we conducted a comprehensive transcriptome analysis of two wheat (Triticum aestivum) near-isogenic lines, the glaucous line G-JM38 rich in cuticular waxes and the non-glaucous line NG-JM31. We identified 85,143 protein-coding mRNAs, 4,485 lncRNAs, and 1,130 miRNAs. Using the lncRNA-miRNA-mRNA network and endogenous target mimic (eTM) prediction, we discovered that lncRNA35557 acted as an eTM for the miRNA tae-miR6206, effectively preventing tae-miR6206 from cleaving the NAC transcription factor gene TaNAC018. This lncRNA-miRNA interaction led to higher transcript abundance for TaNAC018 and enhanced drought-stress tolerance. Additionally, treatment with mannitol and abscisic acid (ABA) each influenced the levels of tae-miR6206, lncRNA35557, and TaNAC018 transcript. The ectopic expression of TaNAC018 in Arabidopsis also improved tolerance toward mannitol and ABA treatment, whereas knocking down TaNAC018 transcript levels via virus-induced gene silencing in wheat rendered seedlings more sensitive to mannitol stress. Our results indicate that lncRNA35557 functions as a competing endogenous RNA to modulate TaNAC018 expression by acting as a decoy target for tae-miR6206 in glaucous wheat, suggesting that non-coding RNA has important roles in the regulatory mechanisms responsible for wheat stress tolerance.


Assuntos
Arabidopsis , MicroRNAs , RNA Longo não Codificante , RNA Endógeno Competitivo , RNA Longo não Codificante/genética , Ácido Abscísico/farmacologia , Arabidopsis/genética , Manitol , MicroRNAs/genética , RNA Mensageiro , Triticum/genética , Ceras
11.
Mol Cancer ; 23(1): 185, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39232758

RESUMO

The spatial arrangement of immune cells within the tumor microenvironment (TME) and their interactions play critical roles in the initiation and development of cancer. Several advanced technologies such as imaging mass cytometry (IMC) providing the immunological landscape of the TME with single-cell resolution. In this study, we develop a new method to quantify the spatial proximity between different cell types based on single-cell spatial data. Using this method on IMC data from 416 lung adenocarcinoma patients, we show that the proximity between different cell types is more correlated with patient prognosis compared to the traditional features such immune cell density and fractions. Consistent with previous reports, our results validate that proximity of T helper (Th) and B cells to cancer cells is associated with survival benefits. More importantly, we discover that the proximity of M2 macrophages to multiple immune cells is associated with poor prognosis. When Th/B cells are stratified into M2-distal and M2-proximal, the abundance of the former but not the latter category of Th/B cells is correlated with enhanced patient survival. Additionally, the abundance of M2-distal and M2-proximal cytotoxic T cells (Tc) is respectively associated with good and poor prognosis. Our results indicate that the prognostic effect of Th, Tc, and B cells in the tumor microenvironment is modulated by the nearby M2 macrophages. The proposed new method proposed can be readily applied to all single-cell spatial data for revealing functional impact of immune cell interactions.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Linfócitos do Interstício Tumoral , Macrófagos , Microambiente Tumoral , Humanos , Prognóstico , Adenocarcinoma de Pulmão/imunologia , Adenocarcinoma de Pulmão/patologia , Adenocarcinoma de Pulmão/mortalidade , Microambiente Tumoral/imunologia , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/mortalidade , Linfócitos do Interstício Tumoral/imunologia , Linfócitos do Interstício Tumoral/metabolismo , Linfócitos do Interstício Tumoral/patologia , Macrófagos/imunologia , Macrófagos/patologia , Macrófagos/metabolismo , Linfócitos B/imunologia , Linfócitos B/patologia , Linfócitos B/metabolismo , Análise de Célula Única/métodos
12.
Int J Cancer ; 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874435

RESUMO

Multiple myeloma (MM) is a heterogeneous disease with a small subset of high-risk patients having poor prognoses. Identifying these patients is crucial for treatment management and strategic decisions. In this study, we developed a novel computational framework to define prognostic gene signatures by selecting genes with expression driven by clonal copy number alterations. We applied this framework to MM and developed a clonal gene signature (CGS) consisting of 22 genes and evaluated in five independent datasets. The CGS provided significant prognostic values after adjusting for well-established factors including cytogenetic abnormalities, International Staging System (ISS), and Revised ISS (R-ISS). Importantly, CGS demonstrated higher performance in identifying high-risk patients compared to the GEP70 and SKY92 signatures recommended for prognostic stratification of MM. CGS can further stratify patients into subgroups with significantly differential prognoses when applied to the high- and low-risk groups identified by GEP70 and SKY92. Additionally, CGS scores are significantly associated with patient response to dexamethasone, a commonly used treatment for MM. In summary, we proposed a computational framework that requires only gene expression data to identify CGSs for prognosis prediction. CGS provides a useful biomarker for improving prognostic stratification in MM, especially for identifying the highest-risk patients.

13.
Int J Cancer ; 154(12): 2151-2161, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38429627

RESUMO

Lung cancer is the first leading cause of cancer-related death in the United States, with lung adenocarcinoma as the major subtype accounting for 40% of all cases. To improve patient survival, image-based prognostic models were developed due to the ready availability of pathological images at diagnosis. However, the application of these models is hampered by two main challenges: the lack of publicly available image datasets with high-quality survival information and the poor interpretability of conventional convolutional neural network models. Here, we integrated matched transcriptomic and H&E staining data from TCGA (The Cancer Genome Atlas) to develop an image-based prognostic model, termed Deep-learning based Cell Graph (DeepCG) model. Instead of survival data, we used a gene signature to predict patient prognostic risks, which was then used as labels for training DeepCG. Importantly, by employing graph structures to capture cell patterns, DeepCG can provide cell-level interpretation, which was more biologically relevant than previous region-level insights. We validated the prognostic values of DeepCG in independent datasets and demonstrated its ability to identify prognostically informative cells in images.


Assuntos
Adenocarcinoma de Pulmão , Neoplasias Pulmonares , Humanos , Modelos de Riscos Proporcionais , Adenocarcinoma de Pulmão/patologia , Neoplasias Pulmonares/patologia , Prognóstico , Perfilação da Expressão Gênica
14.
Int J Cancer ; 155(4): 710-718, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38608177

RESUMO

Thymic carcinoma (TC) is a rare malignant tumor with a poor prognosis, and there is currently limited data on the use of immunotherapy in patients with unresectable TC. In this study, data of patients with unresectable TC diagnosed from January 2017 were retrospectively collected from multiple centers. Treatment response, progression-free survival (PFS), overall survival (OS), survival-independent prognostic factor, and adverse events (AEs) were further analyzed. As a result, a total of 93 patients with unresectable TC were enrolled, of which 54 received first-line chemotherapy, and 39 received chemotherapy plus immune checkpoint inhibitors (ICIs). The objective response rate was 50% (27/54) in the chemotherapy group and 76.9% (30/39) in the chemotherapy plus ICIs group. The chemotherapy plus ICIs group achieved significant median PFS benefit (8.8 vs. 34.9 months, p < .001) and median OS benefit (41.8 months vs. not reached, p = .025). Multivariate analysis showed that ICIs and local therapy were independent prognostic factors for PFS. In addition, 17 patients developed immune-related AEs (IRAEs), of which 15 (38.5%) had Grade 1 or 2 IRAEs and 2 (5.1%) had Grade 3 IRAEs in the chemotherapy plus ICIs group. In conclusion, the efficacy of chemotherapy plus ICIs is superior to chemotherapy, and the adverse effects are manageable in patients with unresectable TC.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica , Inibidores de Checkpoint Imunológico , Timoma , Neoplasias do Timo , Humanos , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Inibidores de Checkpoint Imunológico/uso terapêutico , Inibidores de Checkpoint Imunológico/efeitos adversos , Inibidores de Checkpoint Imunológico/administração & dosagem , Idoso , Neoplasias do Timo/tratamento farmacológico , Neoplasias do Timo/mortalidade , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Timoma/tratamento farmacológico , Timoma/mortalidade , Prognóstico , Intervalo Livre de Progressão
15.
Hum Mol Genet ; 31(16): 2831-2843, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35138370

RESUMO

Differences by sex in lung cancer incidence and mortality have been reported which cannot be fully explained by sex differences in smoking behavior, implying existence of genetic and molecular basis for sex disparity in lung cancer development. However, the information about sex dimorphism in lung cancer risk is quite limited despite the great success in lung cancer association studies. By adopting a stringent two-stage analysis strategy, we performed a genome-wide gene-sex interaction analysis using genotypes from a lung cancer cohort including ~ 47 000 individuals with European ancestry. Three low-frequency variants (minor allele frequency < 0.05), rs17662871 [odds ratio (OR) = 0.71, P = 4.29×10-8); rs79942605 (OR = 2.17, P = 2.81×10-8) and rs208908 (OR = 0.70, P = 4.54×10-8) were identified with different risk effect of lung cancer between men and women. Further expression quantitative trait loci and functional annotation analysis suggested rs208908 affects lung cancer risk through differential regulation of Coxsackie virus and adenovirus receptor gene expression in lung tissues between men and women. Our study is one of the first studies to provide novel insights about the genetic and molecular basis for sex disparity in lung cancer development.


Assuntos
Estudo de Associação Genômica Ampla , Neoplasias Pulmonares , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Humanos , Pulmão , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Masculino , Polimorfismo de Nucleotídeo Único/genética
16.
EMBO J ; 39(12): e103181, 2020 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-32368828

RESUMO

N6-methyladenosine (m6 A) is an abundant nucleotide modification in mRNA, known to regulate mRNA stability, splicing, and translation, but it is unclear whether it is also has a physiological role in the intratumoral microenvironment and cancer drug resistance. Here, we find that METTL3, a primary m6 A methyltransferase, is significantly down-regulated in human sorafenib-resistant hepatocellular carcinoma (HCC). Depletion of METTL3 under hypoxia promotes sorafenib resistance and expression of angiogenesis genes in cultured HCC cells and activates autophagy-associated pathways. Mechanistically, we have identified FOXO3 as a key downstream target of METTL3, with m6 A modification of the FOXO3 mRNA 3'-untranslated region increasing its stability through a YTHDF1-dependent mechanism. Analysis of clinical samples furthermore showed that METTL3 and FOXO3 levels are tightly correlated in HCC patients. In mouse xenograft models, METTL3 depletion significantly enhances sorafenib resistance of HCC by abolishing the identified METTL3-mediated FOXO3 mRNA stabilization, and overexpression of FOXO3 restores m6 A-dependent sorafenib sensitivity. Collectively, our work reveals a critical function for METTL3-mediated m6 A modification in the hypoxic tumor microenvironment and identifies FOXO3 as an important target of m6 A modification in the resistance of HCC to sorafenib therapy.


Assuntos
Adenosina/análogos & derivados , Autofagia/efeitos dos fármacos , Carcinoma Hepatocelular/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteína Forkhead Box O3/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas de Neoplasias/metabolismo , RNA Mensageiro/metabolismo , RNA Neoplásico/metabolismo , Sorafenibe/farmacologia , Adenosina/genética , Adenosina/metabolismo , Animais , Autofagia/genética , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteína Forkhead Box O3/genética , Células HEK293 , Células Hep G2 , Células Endoteliais da Veia Umbilical Humana , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Metilação/efeitos dos fármacos , Metiltransferases/genética , Metiltransferases/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas de Neoplasias/genética , RNA Mensageiro/genética , RNA Neoplásico/genética
17.
Funct Integr Genomics ; 24(2): 72, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594466

RESUMO

BACKGROUND: Colorectal cancer is a malignant tumor of the digestive system originating from abnormal cell proliferation in the colon or rectum, often leading to gastrointestinal symptoms and severe health issues. Nucleotide metabolism, which encompasses the synthesis of DNA and RNA, is a pivotal cellular biochemical process that significantly impacts both the progression and therapeutic strategies of colorectal cancer METHODS: For single-cell RNA sequencing (scRNA-seq), five functions were employed to calculate scores related to nucleotide metabolism. Cell developmental trajectory analysis and intercellular interaction analysis were utilized to explore the metabolic characteristics and communication patterns of different epithelial cells. These findings were further validated using spatial transcriptome RNA sequencing (stRNA-seq). A risk model was constructed using expression profile data from TCGA and GEO cohorts to optimize clinical decision-making. Key nucleotide metabolism-related genes (NMRGs) were functionally validated by further in vitro experiments. RESULTS: In both scRNA-seq and stRNA-seq, colorectal cancer (CRC) exhibited unique cellular heterogeneity, with myeloid cells and epithelial cells in tumor samples displaying higher nucleotide metabolism scores. Analysis of intercellular communication revealed enhanced signaling pathways and ligand-receptor interactions between epithelial cells with high nucleotide metabolism and fibroblasts. Spatial transcriptome sequencing confirmed elevated nucleotide metabolism states in the core region of tumor tissue. After identifying differentially expressed NMRGs in epithelial cells, a risk prognostic model based on four genes effectively predicted overall survival and immunotherapy outcomes in patients. High-risk group patients exhibited an immunosuppressive microenvironment and relatively poorer prognosis and responses to chemotherapy and immunotherapy. Finally, based on data analysis and a series of cellular functional experiments, ACOX1 and CPT2 were identified as novel therapeutic targets for CRC. CONCLUSION: In this study, a comprehensive analysis of NMRGs in CRC was conducted using a combination of single-cell sequencing, spatial transcriptome sequencing, and high-throughput data. The prognostic model constructed with NMRGs shows potential as a standalone prognostic marker for colorectal cancer patients and may significantly influence the development of personalized treatment approaches for CRC.


Assuntos
Neoplasias Colorretais , MicroRNAs , Humanos , RNA-Seq , Nucleotídeos , Análise da Expressão Gênica de Célula Única , Transcriptoma , Redes e Vias Metabólicas , Neoplasias Colorretais/genética , Microambiente Tumoral/genética
18.
Br J Haematol ; 2024 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-39438259

RESUMO

This retrospective study aimed to analyse the course and outcome of recurrent immune thrombocytopenia (ITP) in children and to identify factors associated with recurrence. A total of 497 newly diagnosed ITP children with platelet <30 × 109/L between January 1988 and December 2019 were included. Recurrent ITP was defined as a new event of thrombocytopenia after at least 3 months of remission without treatment. Twenty-nine (5.8%) children experienced 48 recurrent episodes. The median time from diagnosis to recurrence was 22 months. Most recurrences occurred in children aged 1.5-10 years with a recent infection history. Compared to non-recurrent ITP, children with recurrent ITP had delayed remission with lower platelets at 1 month and 3 months postdiagnosis. Multivariate analysis identified aged 1.5-10 years (hazard ratio [HR] 3.65, 95% confidence interval [CI]: 1.35-9.82) and delayed remission at 7-12 months (HR 4.04, 95% CI: 1.37-11.95) as predictors for recurrence. Most recurrent ITP patients had minor or mild symptoms, higher platelet counts, did not require treatment, and achieved remission within 12 months. The similar remission trajectories among the first and recurrent ITP, but different from the courses in the non-recurrent ITP, suggest that recurrent ITP might have a unique biological basis.

19.
Br J Haematol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39137931

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease characterized by a subset of patients who exhibit treatment resistance and poor prognoses. Genomic assays have been widely employed to identify high-risk individuals characterized by rearrangements in the MYC, BCL2 and BCL6 genes. These patients typically undergo more aggressive therapeutic treatments; however, there remains a significant variation in their treatment outcomes. This study introduces an MYC signature score (MYCSS) derived from gene expression profiles, specifically designed to evaluate MYC overactivation in DLBCL patients. MYCSS was validated across several independent cohorts to assess its ability to stratify patients based on MYC-related genetic and molecular aberrations, enhancing the accuracy of prognostic evaluations compared to conventional MYC biomarkers. Our results indicate that MYCSS significantly refines prognostic accuracy beyond that of conventional MYC biomarkers focused on genetic aberrations. More importantly, we found that nearly 50% of patients identified as high risk by traditional MYC metrics actually share similar survival prospects with those having no MYC aberrations. These patients may benefit from standard GCB-based therapies rather than more aggressive treatments. MYCSS provides a robust signature that identifies high-risk patients, aiding in the precision treatment of DLBCL, and minimizing the potential for overtreatment.

20.
Oncologist ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39250742

RESUMO

In multiple myeloma (MM), while frequent mutations in driver genes are crucial for disease progression, they traditionally offer limited insights into patient prognosis. This study aims to enhance prognostic understanding in MM by analyzing pathway dysregulations in key cancer driver genes, thereby identifying actionable gene signatures. We conducted a detailed quantification of mutations and pathway dysregulations in 10 frequently mutated cancer driver genes in MM to characterize their comprehensive mutational impacts on the whole transcriptome. This was followed by a systematic survival analysis to identify significant gene signatures with enhanced prognostic value. Our systematic analysis highlighted 2 significant signatures, TP53 and LRP1B, which notably outperformed mere mutation status in prognostic predictions. These gene signatures remained prognostically valuable even when accounting for clinical factors, including cytogenetic abnormalities, the International Staging System (ISS), and its revised version (R-ISS). The LRP1B signature effectively distinguished high-risk patients within low/intermediate-risk categories and correlated with significant changes in the tumor immune microenvironment. Additionally, the LRP1B signature showed a strong association with proteasome inhibitor pathways, notably predicting patient responses to bortezomib and the progression from monoclonal gammopathy of unknown significance to MM. Through a rigorous analysis, this study underscores the potential of specific gene signatures in revolutionizing the prognostic landscape of MM, providing novel clinical insights that could influence future translational oncology research.

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