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Circular RNAs are a class of covalently closed single-stranded loop RNAs that have been implicated to play a functional role in almost all types of cancers. Previous studies have revealed that circMYBL2 acts as a tumor-promoting circular RNA. In this study, we found that circMYBL2 in colorectal cancer encodes a 185-amino acid protein, p185. Functionally, circMYBL2-encoded p185 suppressed the growth and aggressiveness of colorectal cancer cells in vitro and in vivo. Mechanistically, p185 counteracted ubiquitin C-terminal hydrolase L3 (UCHL3)-mediated deubiquitination of phosphoglycerate dehydrogenase (PHGDH) by competitively binding to the C1 domain of UCHL3, resulting in PHGDH degradation and a subsequent reduction in serine and glycine biosynthesis. These data revealed that the circMYBL2-encoded p185 isoform serves as a tumor suppressor to inhibit the progression of colorectal cancer by reducing serine biosynthesis. Significance: A p185 protein encoded by circMYBL2 functions as a tumor suppressor that inhibits the progression of colorectal cancer by increasing the degradation of PHGDH to reduce serine biosynthesis.
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Neoplasias Colorrectales , Progresión de la Enfermedad , Fosfoglicerato-Deshidrogenasa , ARN Circular , Serina , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Serina/metabolismo , Serina/biosíntesis , Ratones , Animales , ARN Circular/genética , Fosfoglicerato-Deshidrogenasa/metabolismo , Fosfoglicerato-Deshidrogenasa/genética , Ratones Desnudos , Proliferación Celular , Línea Celular Tumoral , Masculino , Ratones Endogámicos BALB C , Femenino , Regulación Neoplásica de la Expresión Génica , Ensayos Antitumor por Modelo de Xenoinjerto , Células HCT116RESUMEN
Phosphatases can dephosphorylate phosphorylated kinases, leading to their inactivation, and ferroptosis is a type of cell death. Therefore, our aim is to identify phosphatases associated with ferroptosis by analyzing the differentially expressed genes (DEGs) of the Luminal A Breast Cancer (LumABC) cohort from the Cancer Genome Atlas (TCGA). An analysis of 260 phosphatase genes from the GeneCard database revealed that out of the 28 DEGs with high expression, only the expression of pyruvate dehydrogenase phosphatase 2 (PDP2) had a significant correlation with patient survival. In addition, an analysis of DEGs using gene ontology, Kyoto Encyclopedia of Genes and Genomes and gene set enrichment analysis revealed a significant variation in the expression of ferroptosis-related genes. To further investigate this, we analyzed 34 ferroptosis-related genes from the TCGA-LumABC cohort. The expression of long-chain acyl-CoA synthetase 4 (ACSL4) was found to have the highest correlation with the expression of PDP2, and its expression was also inversely proportional to the survival rate of patients. Western blot experiments using the MCF-7 cell line showed that the phosphorylation level of ACSL4 was significantly lower in cells transfected with the HA-PDP2 plasmid, and ferroptosis was correspondingly reduced (p < 0.001), as indicated by data from flow cytometry detection of membrane-permeability cell death stained with 7-aminoactinomycin, lipid peroxidation, and Fe2+. Immunoprecipitation experiments further revealed that the phosphorylation level of ACSL4 was only significantly reduced in cells where PDP2 and ACSL4 co-precipitated. These findings suggest that PDP2 may act as a phosphatase to dephosphorylate and inhibit the activity of ACSL4, which had been phosphorylated and activated in LumABC cells. Further experiments are needed to confirm the molecular mechanism of PDP2 inhibiting ferroptosis.
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Neoplasias de la Mama , Ferroptosis , Femenino , Humanos , Neoplasias de la Mama/genética , Coenzima A Ligasas/genética , Ferroptosis/genética , Peroxidación de Lípido , Monoéster Fosfórico Hidrolasas , Fosforilación , Piruvato Deshidrogenasa (Lipoamida)-Fosfatasa/metabolismoRESUMEN
BACKGROUND: Triple-negative breast cancer is a complex breast malignancy subtype characterized by poor prognosis. The pursuit of effective therapeutic approaches for this subtype is considerably challenging. Notably, recent research has illuminated the key role of the tricarboxylic acid cycle in cancer metabolism and the complex landscape of tumor development. Concurrently, an emerging body of evidence underscores the noteworthy role that long non-coding RNAs play in the trajectory of breast cancer development. Despite this growing recognition, the exploration of whether long non-coding RNAs can influence breast cancer progression by modulating the tricarboxylic acid cycle has been limited. Moreover, the underlying mechanisms orchestrating these interactions have not been identified. METHODS: The expression levels of LINC00571 and IDH2 were determined through the analysis of the public TCGA dataset, transcriptome sequencing, qRTâPCR, and Western blotting. The distribution of LINC00571 was assessed using RNA fluorescence in situ hybridization. Alterations in biological effects were evaluated using CCK-8, colony formation, EdU, cell cycle, and apoptosis assays and a tumor xenograft model. To elucidate the interaction between LINC00571, HNRNPK, and ILF2, RNA pull-down, mass spectrometry, coimmunoprecipitation, and RNA immunoprecipitation assays were performed. The impacts of LINC00571 and IDH2 on tricarboxylic acid cycle metabolites were investigated through measurements of the oxygen consumption rate and metabolite levels. RESULTS: This study revealed the complex interactions between a novel long non-coding RNA (LINC00571) and tricarboxylic acid cycle metabolism. We validated the tumor-promoting role of LINC00571. Mechanistically, LINC00571 facilitated the interaction between HNRNPK and ILF2, leading to reduced ubiquitination and degradation of ILF2, thereby stabilizing its expression. Furthermore, ILF2 acted as a transcription factor to enhance the expression of its downstream target gene IDH2. CONCLUSIONS: Our study revealed that the LINC00571/HNRNPK/ILF2/IDH2 axis promoted the progression of triple-negative breast cancer by regulating tricarboxylic acid cycle metabolites. This discovery provides a novel theoretical foundation and new potential targets for the clinical treatment of triple-negative breast cancer.
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ARN Largo no Codificante , Neoplasias de la Mama Triple Negativas , Humanos , Línea Celular Tumoral , Neoplasias de la Mama Triple Negativas/patología , Ciclo del Ácido Cítrico , Hibridación Fluorescente in Situ , ARN/metabolismo , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Ribonucleoproteína Heterogénea-Nuclear Grupo K/metabolismo , Proteína del Factor Nuclear 45/genética , Proteína del Factor Nuclear 45/metabolismoRESUMEN
Gankyrin is found in high levels in triple-negative breast cancer (TNBC) and has been established to form a complex with the E3 ubiquitin ligase MDM2 and p53, resulting in the degradation of p53 in hepatocarcinoma cells. Therefore, this study sought to determine whether gankyrin could inhibit ferroptosis through this mechanism in TNBC cells. The expression of gankyrin was investigated in relation to the prognosis of TNBC using bioinformatics. Co-immunoprecipitation and GST pull-down assays were then conducted to determine the presence of a gankyrin and MDM2 complex. RT-qPCR and immunoblotting were used to examine molecules related to ferroptosis, such as gankyrin, p53, MDM2, SLC7A11, and GPX4. Additionally, cell death was evaluated using flow cytometry detection of 7-AAD and a lactate dehydrogenase release assay, as well as lipid peroxide C11-BODIPY. Results showed that the expression of gankyrin is significantly higher in TNBC tissues and cell lines, and is associated with a poor prognosis for patients. Subsequent studies revealed that inhibiting gankyrin activity triggered ferroptosis in TNBC cells. Additionally, silencing gankyrin caused an increase in the expression of the p53 protein, without altering its mRNA expression. Co-immunoprecipitation and GST pull-down experiments indicated that gankyrin and MDM2 form a complex. In mouse embryonic fibroblasts lacking both MDM2 and p53, this gankyrin/MDM2 complex was observed to ubiquitinate p53, thus raising the expression of molecules inhibited by ferroptosis, such as SLC7A11 and GPX4. Furthermore, silencing gankyrin in TNBC cells disrupted the formation of the gankyrin/MDM2 complex, hindered the degradation of p53, increased SLC7A11 expression, impeded cysteine uptake, and decreased GPX4 production. Our findings suggest that TNBC cells are able to prevent cell ferroptosis through the gankyrin/p53/SLC7A11/GPX4 signaling pathway, indicating that gankyrin may be a useful biomarker for predicting TNBC prognosis or a potential therapeutic target.
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Ferroptosis , Neoplasias de la Mama Triple Negativas , Humanos , Animales , Ratones , Proteínas Proto-Oncogénicas c-mdm2/metabolismo , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/patología , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Fibroblastos/metabolismo , Sistema de Transporte de Aminoácidos y+/genéticaRESUMEN
To address the issue of pipeline blockage caused by the formation of waxy deposits inside pipelines, hindering the flow of petroleum in the Shengli oilfield, eight new-style polyacrylic acid pour point depressants (PPD) for Shengli crude oil were prepared by maleic anhydride and ene monomers with different polar and aromatic pendant chains. The synthesized Pour Point Depressants were characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), gel permeation chromatography (GPC), and polarizing optical microscopy (POM). The results were promising and demonstrated that any type of pour point depressant exhibited excellent performance on high-pour-point crude oil. The reduction in pour-point after additive addition was largely dependent on the polymer structure. Notably, polymers containing long alkyl side chains and aromatic units displayed the most impressive performance, capable of depressing the pour point by 12 °C.
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Increasing studies have suggested that some cardiac glycosides, such as conventional digoxin (DIG) and digitoxin, can induce immunogenic cell death (ICD) in various tumors. We previously found that 3'-epi-12ß-hydroxyfroside (HyFS), a novel cardenolide compound isolated by our group, could induce cytoprotective autophagy through inactivation of the Akt/mTOR pathway. However, whether HyFS can induce ICD remains unknown. In this study, we extend our work to further investigate whether HyFS could induce both autophagy and ICD, and we investigated the relationship between autophagy and ICD in three TNBC cell lines. Unexpectedly, compared to DIG, we found that HyFS could induce complete autophagy flux but not ICD in three human triple-negative breast cancer (TNBC) cell lines and one murine TNBC model. Inhibition of HyFS-induced autophagy resulted in the production of ICD in TNBC MDA-MB-231, MDA-MB-436, and HCC38 cells. A further mechanism study showed that formation of RIPK1/RIPK3 necrosomes was necessary for ICD induction in DIG-treated TNBC cells, while HyFS treatment led to receptor-interacting serine-threonine kinase (RIPK)1/3 necrosome degradation via an autophagy process. Additionally, inhibition of HyFS-induced autophagy by the autophagy inhibitor chloroquine resulted in the reoccurrence of ICD and reversion of the tumor microenvironment, leading to more significant antitumor effects in immunocompetent mice than in immunodeficient mice. These findings indicate that HyFS-mediated autophagic degradation of RIPK1/RIPK3 necrosomes leads to inactivation of ICD in TNBC cells. Moreover, combined treatment with HyFS and an autophagy inhibitor may enhance the antitumor activities, suggesting an alternative therapeutic for TNBC treatment.
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Neoplasias de la Mama Triple Negativas , Animales , Humanos , Ratones , Apoptosis , Autofagia , Línea Celular Tumoral , Muerte Celular Inmunogénica , Proteína Serina-Treonina Quinasas de Interacción con Receptores/metabolismo , Neoplasias de la Mama Triple Negativas/metabolismo , Microambiente TumoralRESUMEN
Long noncoding RNAs (lncRNAs) play crucial regulatory roles in the progression of various cancers. However, the functional roles of lncRNAs in breast cancer remain unclear. In this study, we investigated the functional role of a novel long noncoding RNA SEMA3B-AS1 (lncRNA SEAS1) in breast cancer progression and the underlying mechanisms. SEAS1 was downregulated in the triple-negative breast cancer (TNBC) tissues compared with the para-carcinoma tissues, which was associated with poor prognosis of TNBC patients. We demonstrated that SEAS1 knockdown significantly increased the proliferation, migration, and invasion of TNBC cell lines, whereas SEAS1 overexpression reversed these effects. Bioinformatics analysis demonstrated that microRNA (miR)-3940-3p was a potential target of SEAS1. Mechanistically, RNA immunoprecipitation (RIP) and luciferase reporter assays confirmed that lncRNA SEMA3B-AS1 acted as sponge for miR-3940-3p, preventing the degradation of its target gene KLLN, which acts as a tumor-inhibiter in TNBC. Moreover, RNA pulldown, mass spectrometry, ChIP, and luciferase reporter assays confirmed that SMAD3 directly interacted with the promoter of SEAS1 and suppressed its transcription, thereby promoting TNBC progression. The clinical samples of TNBC confirmed SEAS1 was correlated inversely with lymphatic and distant metastasis. In conclusion, our findings reveal a novel pathway for TNBC progression via SMAD3/lncRNA SEAS1/miR-3940-3p/KLLN axis, and suggest that SEAS1 may serve as a potential biomarker and therapeutic target for TNBC.
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MicroARNs , ARN Largo no Codificante , Semaforinas , Neoplasias de la Mama Triple Negativas , Movimiento Celular/genética , Proliferación Celular/genética , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Humanos , Glicoproteínas de Membrana/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Semaforinas/genética , Semaforinas/metabolismo , Neoplasias de la Mama Triple Negativas/patologíaRESUMEN
We propose an explicitly calculable example of holography on three-dimensional de Sitter space by providing a prescription to analytic continue a higher-spin holography on three-dimensional anti-de Sitter space. Applying the de Sitter holography, we explicitly compute bulk correlation functions on three-dimensional de Sitter space at late time in a higher-spin gravity. These expressions are consistent with recent analysis based on bulk Feynman diagrams. Our explicit computations reveal how holographic computations could provide fruitful information.
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Background: The role of human epidermal growth factor receptor 2 (HER2) in metaplastic breast cancer (MBC) patients remains unclear. The present study aimed to evaluate the effect of HER2 status on MBC patients by propensity-score matching (PSM). Methods: The SEER data from 2010 to 2016 were extracted. The breast cancer-specific survival (BCSS) of MBC patients, diagnosed from 2001 to 2016, was compared using Kaplan-Meier analysis. The multivariate Cox proportional model between groups was performed. PSM was used to make 1:1 case-control matching. Results: We included 1887 patients with a median follow-up time of 28 months (range 1-83 months). 1749 (92.7%) and 138 (7.3%) patients presented in the HER2-negative group and HER2-positive group. 833 (44.1%) patients received post-mastectomy radiotherapy (PMRT). The HER2-positive group had younger patients, lower tumor grades, and more advanced tumor stages. The prognoses were related to age of diagnosis, race/ethnicity, TNM stage, and PMRT in multivariate Cox analysis. ER status and HER2 status had no impact on BCSS. In the Kaplan-Meier analysis, PMRT was associated with a better prognosis. Importantly, patients with HER2-negative status can benefit from PMRT, but not those with HER2-positive status. After PSM, on multivariate Cox analysis, the prognosis was related to HER2 status and PMRT. In the Kaplan-Meier analysis, PMRT was related to a better prognosis for HER2-negative patients. Conclusions: Our findings supported that PMRT and HER2-positive status were associated with a better prognosis after PSM. However, HER2-negative, but not HER2-positive patients could benefit from PMRT.
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Neoplasias de la Mama , Receptor ErbB-2 , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Humanos , Mastectomía , Puntaje de Propensión , Receptor ErbB-2/genéticaRESUMEN
BACKGROUND: Several agents for oncolytic immunotherapy have been approved for clinical use, but monotherapy is modest for most oncolytic agents. The combination of several therapeutic strategies through recombinant and nanotechnology to engineer multifunctional oncolytic viruses for oncolytic immunotherapy is a promising strategy. METHODS: An endothelium-targeting iRGD-liposome encapsulating a recombinant Newcastle disease virus (NDV), which expresses the dendritic cell (DC) chemokine MIP-3α (iNDV3α-LP), and three control liposomes were constructed. MIP-3α, HMGB1, IgG, and ATP were detected by western blotting or ELISA. The chemotaxis of DCs was examined by Transwell chambers. The phenotypes of the immune cells were analyzed by flow cytometry. The antitumor efficiency was investigated in B16 and 4T1 tumor-bearing mice. Immunofluorescence and immunohistochemistry were used to observe the localization of liposomes, molecular expression and angiogenesis. Synergistic index was calculated using the data of tumor volume, tumor angiogenesis and tumor-infiltrating lymphocytes. RESULTS: Compared with NDV-LP, treatment with iNDV3α-LP and NDV3α-LP induced stronger virus replication and cell lysis in B16 and 4T1 tumor cells and human umbilical vein endothelial cells (HUVECs) with the best response observed following iNDV3α-LP treatment. B16 and 4T1 cells treated with iNDV3α-LP produced more damage-associated molecular pattern molecules, including secreted HMGB1, ATP, and calreticulin. Moreover, iNDV3α-LP specifically bound to αvß3-expressing 4T1 cells and HUVECs and to tumor neovasculature. Tumor growth was significantly suppressed, and survival was longer in iNDV3α-LP-treated B16-bearing and 4T1-bearing mice. A mechanism study showed that iNDV3α-LP treatment initiated the strongest tumor-specific cellular and humoral immune response. Moreover, iNDV3α-LP treatment could significantly suppress tumor angiogenesis and reverse the tumor immune suppressive microenvironment in both B16-bearing and 4T1-bearing mice. CONCLUSIONS: In this study, iNDV3α-LP had several functions, such as tumor and vessel lysis, MIP-3α immunotherapy, and binding to αvß3-expressing tumor and its neovasculature. iNDV3α-LP treatment significantly suppressed tumor angiogenesis and reversed the tumor immunosuppressive microenvironment. These findings offer a strong rationale for further clinical investigation into a combination strategy for oncolytic immunotherapy, such as the formulation iNDV3α-LP in this study.
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Proteína HMGB1 , Neoplasias , Viroterapia Oncolítica , Adenosina Trifosfato/metabolismo , Animales , Células Endoteliales , Endotelio , Proteína HMGB1/metabolismo , Humanos , Factores Inmunológicos , Inmunoterapia , Liposomas/metabolismo , Ratones , Neoplasias/terapia , Virus de la Enfermedad de Newcastle , Microambiente TumoralRESUMEN
It has been previously reported that transcription factor-microRNA (TF-miRNA) axes play a significant role in the carcinogenesis of several types of malignant tumor. However, there is a lack of research into the differences in the mechanism of Helicobacter pylori (HP)-positive [HP(+)] and HP-negative [HP(-)] gastric cancer. The aim of the present study was to identify the hub genes and TF-miRNA axes, and to determine the potential mechanisms involved in HP-associated gastric cancer. HP-associated mRNA and miRNA data, as well as the corresponding clinical information, was downloaded from The Cancer Genome Atlas database. Differentially expressed genes (DEGs) and DE miRNAs (DEMs) were then identified from the HP(+) and HP(-) cancer mRNA and miRNA datasets, respectively. Subsequently, gene set enrichment analysis and the protein-protein interaction (PPI) networks were investigated using the ClusterProfiler packages. Lastly, TF-miRNA-DEG networks were constructed using the miRWalk online tool. A total of 1,050 DEGs and 13 DEMs were identified from the normalized mRNA and miRNA expression datasets, respectively. In addition, 180 Gene Ontology terms and 30 Kyoto Encyclopedia of Genes and Genomes pathways were found to be enriched, while 6 hub genes were identified from the PPI analysis. Furthermore, 7 TF-miRNA interactions and 181 TF-miRNA-DEG axes were constructed using an integrated bioinformatics approach, while 2 TF-miRNA interactions (ZEB1-miRNA-144-3p and PAX2-miRNA-592) were confirmed using reverse transcription-quantitative PCR in samples from enrolled patients. Moreover, the ZEB1-miRNA-144-3p axis was further validated based on dual luciferase reporter assay results. In summary, an integrated bioinformatics approach was used to screen the significant molecular and regulatory axes, which may provide a novel direction to investigate the pathogenesis of gastric cancer associated with HP.
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BACKGROUND: N6-methyladenosine (m6A) is the most common post-transcriptional modification at the RNA level. However, the exact molecular mechanisms of m6A epigenetic regulation in breast cancer remain largely unknown and need to be fully elucidated. METHODS: The integrating bioinformatics analyses were used to screen clinical relevance and dysregulated m6A "reader" protein YTHDF1 in breast cancer from TCGA databases, which was further validated in a cohort of clinical specimens. Furthermore, functional experiments such as the CCK-8 assay, EdU assay, wound healing assay, transwell invasion assay and cell cycle assay were used to determine the biological role of YTHDF1 in breast cancer. RIP, m6A-IP, and CLIP assays were used to find the target of YTHDF1 and further verification by RT-qPCR, western blot, polysome profiling assay. The protein-protein interaction between YTHDF1 and FOXM1 was detected via co-immunoprecipitation. RESULTS: Our study showed that YTHDF1 was overexpressed in breast cancer cells and clinical tissues specimens. At the same time, the high expression level of YTHDF1 was positively correlated with tumor size, lymph node invasion, and distant metastasis in breast cancer patients. YTHDF1 depletion repressed the proliferation, invasion and epithelial-mesenchymal transformation (EMT) and induced G0/G1 phase cell cycle arrest of breast cancer cells in vitro and in vivo. We also demonstrated that FOXM1 is a target of YTHDF1. Through recognizing and binding to the m6A-modified mRNA of FOXM1, YTHDF1 accelerated the translation process of FOXM1 and promoted breast cancer metastasis. Whereas overexpression of FOXM1 in breast cancer cells partially counteracted the tumor suppressed effects caused by YTHDF1 silence, which further verified the regulatory relationship between YTHDF1 and FOXM1. CONCLUSION: Our study reveals a novel YTHDF1/FOXM1 regulatory pathway that contributes to metastasis and progression of breast cancer, suggesting that YTHDF1 might be applied as a potential biomarker and therapeutic target. That also advances our understanding of the tumorigenesis for breast cancer from m6A epigenetic regulation.
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Background: The aim of this paper was to identify an immunotherapy-sensitive subtype for estrogen receptor-positive breast cancer (ER+ BC) patients by exploring the relationship between cancer genetic programs and antitumor immunity via multidimensional genome-scale analyses. Methods: Multidimensional ER+ BC high-throughput data (raw count data) including gene expression profiles, copy number variation (CNV) data, single-nucleotide polymorphism mutation data, and relevant clinical information were downloaded from The Cancer Genome Atlas to explore an immune subtype sensitive to immunotherapy using the Consensus Cluster Plus algorithm based on multidimensional genome-scale analyses. One ArrayExpress dataset and eight Gene Expression Omnibus (GEO) datasets (GEO-meta dataset) as well as the Molecular Taxonomy of Breast Cancer International Consortium dataset were used as validation sets to confirm the findings regarding the immune profiles, mutational features, and survival outcomes of the three identified immune subtypes. Moreover, the development trajectory of ER+ BC patients from the single-cell resolution level was also explored. Results: Through comprehensive bioinformatics analysis, three immune subtypes of ER+ BC (C1, C2, and C3, designated the immune suppressive, activation, and neutral subtypes, respectively) were identified. C2 was associated with up-regulated immune cell signatures and immune checkpoint genes. Additionally, five tumor-related pathways (transforming growth factor, epithelial-mesenchymal transition, extracellular matrix, interferon-γ, and WNT signaling) tended to be more activated in C2 than in C1 and C3. Moreover, C2 was associated with a lower tumor mutation burden, a decreased neoantigen load, and fewer CNVs. Drug sensitivity analysis further showed that C2 may be more sensitive to immunosuppressive agents. Conclusion: C2 (the immune activation subtype) may be sensitive to immunotherapy, which provides new insights into effective treatment approaches for ER+ BC.
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BACKGROUND: Circular RNAs (circRNAs) are a class of non-coding RNA that play critical roles in the development and pathogenesis of various cancers. The circRNA circGSK3B (hsa_circ_0003763) has been shown to enhance cell proliferation, migration, and invasion in hepatocellular carcinoma. However, the specific functions and underlying mechanistic involvement of circGSK3B in gastric cancer (GC) have not yet been explored. Our study aimed to investigate the effect of circGSK3B on the progression of GC and to identify any potential mechanisms underlying this process. METHODS: CircRNA datasets associated with GC were obtained from the PubMed, GEO, and ArrayExpress databases, and circRNAs were validated via RT-qPCR and Sanger sequencing. Biotin-labeled RNA pull-down, mass spectrometry, RNA immunoprecipitation, and in vitro binding assays were employed to determine proteins demonstrating interactions with circGSK3B. Gene expression regulation was assessed through RT-qPCR, chromatin immunoprecipitation, and western blot assays. Gain- and loss-of-function assays were used to analyze any effects of circGSK3B and its partner regulatory molecule (EZH2) on the proliferation, invasion, and migration abilities of GC cells both in vitro and in vivo. RESULTS: CircGSK3B was mainly identified in the nucleus. This circRNA was present at a reduced concentration in GC tissues and cell lines. Overexpression of circGSK3B was shown to inhibit the growth, invasion, and metastasis of GC cells both in vitro and in vivo. Mechanistically, circGSK3B directly interacted with EZH2, acting to suppress the binding of EZH2 and H3K27me3 to the RORA promoter, and leading to an elevation in RORA expression and ultimately the suppression of GC progression. CONCLUSIONS: CircGSK3B acts as a tumor suppressor, reducing EZH2 trans-inhibition and GC progression. This demonstrates the potential use of this RNA as a therapeutic target for GC.
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Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Regulación Neoplásica de la Expresión Génica , Glucógeno Sintasa Quinasa 3 beta/genética , Miembro 1 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , ARN Circular/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Animales , Apoptosis/genética , Biomarcadores de Tumor , Línea Celular Tumoral , Movimiento Celular/genética , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Epigénesis Genética , Perfilación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Xenoinjertos , Humanos , Masculino , Ratones , Modelos Biológicos , Unión Proteica , Interferencia de ARN , Transducción de Señal , Neoplasias Gástricas/patologíaRESUMEN
OBJECTIVE: Various studies have suggested that metabolic genes play a significant role in papillary thyroid cancer (PTC). The current study aimed to identify a metabolic signature related biomarker to predict the prognosis of patients with PTC. METHODS: We conducted a comprehensive analysis on the data obtained from the Cancer Genome Atlas (TCGA) database. The correlation between survival result and metabolic genes was evaluated based on the univariate Cox analyses, least absolute shrinkage and selection operator (LASSO) and multivariate Cox analyses. The performance of a 7-gene signature was assessed according to Kaplan-Meier and receiver operating characteristic (ROC) analysis. Multivariate Cox regression analysis was adopted to unearth clinical factors related to the recurrence free survival (RFS) of patients with PTC. Finally, a prognostic nomogram was developed based on risk score, cancer status and cancer width to improve the prediction for RFS of PTC patients. RESULTS: Seven metabolic genes were used to establish the prognostic model. The ROC curve and C-index exhibited high value in training, testing and the whole TCGA datasets. The established nomogram, incorporating the 7-metabolic gene signature and clinical factors, was able to predict the RFS with high effectiveness. The 7-metabolic gene signature-based nomogram had a good performance to predict the RFS of patients with PTC. CONCLUSION: Our study identified a 7-metabolic gene signature and established a prognostic nomogram, which were useful in predicting the RFS of PTC.
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Biomarcadores de Tumor/genética , Redes y Vías Metabólicas , Nomogramas , Cáncer Papilar Tiroideo/mortalidad , Neoplasias de la Tiroides/mortalidad , Bases de Datos Genéticas , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Estadificación de Neoplasias , Pronóstico , Análisis de Supervivencia , Cáncer Papilar Tiroideo/genética , Cáncer Papilar Tiroideo/patología , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patologíaRESUMEN
OBJECTIVE: Previous investigations of circulating tumor cells (CTCs) have mainly focused on their genomic or transcriptomic features, leaving their epigenetic landscape relatively uncharacterized. Here, we investigated the genome-wide DNA methylome of CTCs with a view to understanding the epigenetic regulatory mechanisms underlying cancer metastasis. METHODS: We evaluated single-cell DNA methylome and copy number alteration (CNA) in 196 single cells, including 107 CTCs collected from 17 cancer patients covering six different cancer types. Our single-cell bisulfite sequencing (scBS-seq) covered on average 11.78% of all CpG dinucleotides and accurately deduced the CNA patterns at 500 kb resolution. RESULTS: We report distinct subclonal structures and different evolutionary histories of CTCs inferred from CNA and DNA methylation profiles. Furthermore, we demonstrate potential tumor origin classification based on the tissue-specific DNA methylation profiles of CTCs. CONCLUSIONS: Our work provides a comprehensive survey of genome-wide DNA methylome in single CTCs and reveals 5-methylcytosine (5-mC) heterogeneity in CTCs, addressing the potential epigenetic regulatory mechanisms underlying cancer metastasis and facilitating the future clinical application of CTCs.
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The selective oxidation of amines into imines is a priority research topic in organic synthesis and has attracted much attention over the past few decades. However, the oxidation of amines generally suffers from the drawback of transition-metal, even noble-metal catalysts. Thus, the strategy of metal- and oxidant-free selective synthesis of imines is highly desirable yet largely unmet. This paper unravels a metal-free and external oxidant-free electrochemical strategy for the oxidative coupling methodology of amines. This general transformation is compatible with various functional amines and led to functionalized imines in moderate to satisfactory yields.
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Cervical cancer is one of the most common female malignancy that occurs worldwide and is reported to cause over 300,000 deaths in 2018. Autophagy controls the survival and death of cancerous cells by regulating the degradation process of cytoplasm and cellular organelle. In the present study, the differentially expressed autophagy-related genes (ARGs) between healthy and cancerous cervical tissues (squamous cell neoplasms) were obtained using data from GTEx and The Cancer Genome Atlas (TCGA) database. The functionalities of the differentially expressed ARGs were analyzed using Gene Ontology (GO) as well as the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. Next, we conducted univariate Cox regression assay and obtained 12 ARGs that were associated with the prognosis of cervical cancer patients. We carried out a multivariate Cox regression analysis and developed six ARG-related prognostic signature for the survival prediction of patients with squamous cell cervical cancer (Risk score = - 0.63*ATG3-0.42*BCL2 + 0.85*CD46-0.38*IFNG+ 0.23*NAMPT+ 0.82*TM9SF1). Following the calculation of risk score using the signature, the patients were divided into high and low-risk groups according to the median value. Kaplan-Meier curve demonstrated that patients with a high-risk score tend to have a poor prognosis (P < 0.001). The value for area under the curves corresponding to the receiver operating characteristic (ROC) was 0.740. As observed, the expression of IFNG was negatively associated with lymph node metastasis (P = 0.026), while a high-risk score was significantly associated with increased age (P = 0.008). To further validate the prognostic signature, we carried out a permutation test and confirmed the performance of the risk score. In conclusion, our study developed six ARG-related prognostic signature for patients with squamous cell cervical cancer, which might help in improving the prognostic predictions of such patients.
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Autofagia/genética , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias del Cuello Uterino/genética , Femenino , Humanos , Pronóstico , Neoplasias del Cuello Uterino/patologíaRESUMEN
BACKGROUND: Thyroid papillary carcinoma (TPC) is the most common type of thyroid cancer (TC). The prognosis of TPC patients with tumor-cell metastasis is poor. Therefore, this study aims to develop a model for predicting TPC patients' recurrence-free survival (RFS). METHODS: We included 546 TPC patients who were clinically and pathologically diagnosed with TPC. The methylation biomarkers that associate with RFS were explored. These 546 samples were divided into training dataset (first 70%) and validation dataset (remaining 30%) randomly. The training dataset was used to identify prognostic biomarkers and construct risk prediction model, in addition, the validation dataset was used to verify the predictive performance of the model. We used Cox proportional hazard analysis and the least absolute shrinkage and selection operator (LASSO) Cox regression analysis to identify the significant predictive biomarkers, and establish the relapse risk prediction model from the identified biomarkers. RESULTS: A 6-DNA methylation signature yielded a high evaluative performance for RFS. The Kaplan-Meier analysis indicated that the 6-DNA methylation signature could significantly distinguish the high- and low-risk patients in training, validation and entire sets. In addition, a nomogram was constructed based on risk score, metastasis status and residual tumor status, and C-index, receiver operating characteristic (ROC) and the calibration plots analysis which demonstrated the good performance and clinical utility of the nomogram. CONCLUSIONS: The results suggested that the 6-DNA methylation signature is the independent prognostic marker for RFS and functioned as a significant tool for guiding the clinical treatment of TPC patients.
Asunto(s)
Biomarcadores de Tumor/genética , Metilación de ADN , Técnicas de Apoyo para la Decisión , Epigenoma , Epigenómica , Nomogramas , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Bases de Datos Genéticas , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Valor Predictivo de las Pruebas , Supervivencia sin Progresión , Reproducibilidad de los Resultados , Medición de Riesgo , Factores de Riesgo , Cáncer Papilar Tiroideo/mortalidad , Cáncer Papilar Tiroideo/cirugía , Neoplasias de la Tiroides/mortalidad , Neoplasias de la Tiroides/cirugía , Tiroidectomía , Factores de Tiempo , Adulto JovenRESUMEN
DNA methylation has been reported to serve an important role in the carcinogenesis and development of gastric cancer. Our aim was to systematically develop an individualized prediction model of the survival risk combing clinical and methylation factors in gastric cancer. A univariate Cox proportional risk regression analysis was used to identify the prognosis-associated methylation sites based on the differentially expressed methylation sites between early and advanced gastric cancer group, then we applied least absolute shrinkage and selection operator (LASSO) Cox regression model to screen candidate methylation sites. Subsequently, multivariate Cox proportional risk regression analysis was conducted to identify predictive signature according to the candidate sites. Relative operating characteristic curve (ROC) analysis manifested that an 11-methylation signature exhibited great predictive efficiency for 1-, 3-, 5-year survival events. Patients in the low-risk group classified according to 11-methylation signature-based risk score yield significantly better survival than that in high-risk group. Moreover, Cox regression analysis combing methylation-based risk score and other clinical factors indicated that 11-methylation signature served as an independent risk factor. The predictive value of risk score was validated in the testing dataset. In addition, a nomogram was constructed and the ROC as well as calibration plots analysis demonstrated the good performance and clinical application of the nomogram. In conclusion, the result suggested the 11-DNA methylation signature may be potentially independent prognostic marker and functioned as a significant tool for guiding the clinical prediction of gastric cancer patients' overall survival.