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Ipomoeassin F (Ipom-F) is a natural compound with embedded carbohydrates that exhibits a potent cytotoxic effect on triple-negative breast cancer (TNBC) cells. The mechanism behind this selective potency remains unclear. To elucidate this mechanism, we analyzed the proteome profiles of the TNBC MDA-MB-231 cells after exposure to Ipom-F at different time points and increasing doses using a quantitative proteomic method. Our proteomic data demonstrate that the major effect of Ipom-F on MDA-MB-231 cells is the inhibition of membrane and secreted protein expression. Our proteomic data are consistent with the recently uncovered molecular mechanism of action of Ipom-F, which binds to Sec61-α and inhibits the co-translational import of proteins into the endoplasmic reticulum. We have defined a subset of membrane and secreted proteins that are particularly sensitive to Ipom-F. Analysis of the expression of these Ipom-F-sensitive proteins in cancer cell lines and breast cancer tissues demonstrates that some of these proteins are upregulated in TNBC cells. Thus, it is likely that TNBC cells may have adapted to the elevated levels of some proteins identified as sensitive to Ipom-F in this study; inhibition of the expression of these proteins leads to a crisis in proliferation and/or survival for the cells.
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Receptor de Anafilatoxina C5a , Humanos , Receptor de Anafilatoxina C5a/metabolismo , Receptor de Anafilatoxina C5a/inmunología , Receptor de Anafilatoxina C5a/genética , Animales , Ratones , Microambiente Tumoral/inmunología , Neoplasias/radioterapia , Neoplasias/inmunología , Neoplasias/metabolismoRESUMEN
Translational studies benefit from experimental designs where laboratory organisms use human-relevant behaviors. One such behavior is decision-making, however studying complex decision-making in rodents is labor-intensive and typically restricted to two levels of cost/reward. We design a fully automated, inexpensive, high-throughput framework to study decision-making across multiple levels of rewards and costs: the REward-COst in Rodent Decision-making (RECORD) system. RECORD integrates three components: 1) 3D-printed arenas, 2) custom electronic hardware, and 3) software. We validated four behavioral protocols without employing any food or water restriction, highlighting the versatility of our system. RECORD data exposes heterogeneity in decision-making both within and across individuals that is quantifiably constrained. Using oxycodone self-administration and alcohol-consumption as test cases, we reveal how analytic approaches that incorporate behavioral heterogeneity are sensitive to detecting perturbations in decision-making. RECORD is a powerful approach to studying decision-making in rodents, with features that facilitate translational studies of decision-making in psychiatric disorders.
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Conducta Animal , Toma de Decisiones , Animales , Masculino , Ratas , Ratones , Oxicodona/administración & dosificación , Recompensa , Consumo de Bebidas Alcohólicas/psicología , Conducta Alimentaria , Autoadministración , Programas InformáticosRESUMEN
BACKGROUND: Organisms frequently experience environmental stresses that occur in predictable patterns and combinations. For wild Saccharomyces cerevisiae yeast growing in natural environments, cells may experience high osmotic stress when they first enter broken fruit, followed by high ethanol levels during fermentation, and then finally high levels of oxidative stress resulting from respiration of ethanol. Yeast have adapted to these patterns by evolving sophisticated "cross protection" mechanisms, where mild 'primary' doses of one stress can enhance tolerance to severe doses of a different 'secondary' stress. For example, in many yeast strains, mild osmotic or mild ethanol stresses cross protect against severe oxidative stress, which likely reflects an anticipatory response important for high fitness in nature. RESULTS: During the course of genetic mapping studies aimed at understanding the mechanisms underlying natural variation in ethanol-induced cross protection against H2O2, we found that a key H2O2 scavenging enzyme, cytosolic catalase T (Ctt1p), was absolutely essential for cross protection in a wild oak strain. This suggested the absence of other compensatory mechanisms for acquiring H2O2 resistance in that strain background under those conditions. In this study, we found surprising heterogeneity across diverse yeast strains in whether CTT1 function was fully necessary for acquired H2O2 resistance. Some strains exhibited partial dispensability of CTT1 when ethanol and/or salt were used as mild stressors, suggesting that compensatory peroxidases may play a role in acquired stress resistance in certain genetic backgrounds. We leveraged global transcriptional responses to ethanol and salt stresses in strains with different levels of CTT1 dispensability, allowing us to identify possible regulators of these alternative peroxidases and acquired stress resistance in general. CONCLUSIONS: Ultimately, this study highlights how superficially similar traits can have different underlying molecular foundations and provides a framework for understanding the diversity and regulation of stress defense mechanisms.
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Peróxido de Hidrógeno , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/fisiología , Saccharomyces cerevisiae/efectos de los fármacos , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/metabolismo , Etanol/farmacología , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Estrés Oxidativo/efectos de los fármacos , Estrés Fisiológico/genética , Estrés Fisiológico/efectos de los fármacos , Presión Osmótica , Catalasa/metabolismo , Catalasa/genética , Variación GenéticaRESUMEN
BACKGROUND: The prevalence of obesity-associated insulin resistance (IR) is increasing along with the increase in obesity rates. In this study, we compared the predictive utility of four alternative indexes of IR [triglyceride glucose index (TyG index), metabolic score for insulin resistance (METS-IR), the triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio and homeostatic model assessment of insulin resistance (HOMA-IR)] for all-cause mortality and cardiovascular mortality in the general population based on key variables screened by the Boruta algorithm. The aim was to find the best replacement index of IR. METHODS: In this study, 14,653 participants were screened from the National Health and Nutrition Examination Survey (2001-2018). And TyG index, METS-IR, TG/HDL-C and HOMA-IR were calculated separately for each participant according to the given formula. The predictive values of IR replacement indexes for all-cause mortality and cardiovascular mortality in the general population were assessed. RESULTS: Over a median follow-up period of 116 months, a total of 2085 (10.23%) all-cause deaths and 549 (2.61%) cardiovascular disease (CVD) related deaths were recorded. Multivariate Cox regression and restricted cubic splines analysis showed that among the four indexes, only METS-IR was significantly associated with both all-cause and CVD mortality, and both showed non-linear associations with an approximate "U-shape". Specifically, baseline METS-IR lower than the inflection point (41.33) was negatively associated with mortality [hazard ratio (HR) 0.972, 95% CI 0.950-0.997 for all-cause mortality]. In contrast, baseline METS-IR higher than the inflection point (41.33) was positively associated with mortality (HR 1.019, 95% CI 1.011-1.026 for all-cause mortality and HR 1.028, 95% CI 1.014-1.043 for CVD mortality). We further stratified the METS-IR and showed that significant associations between METS-IR levels and all-cause and cardiovascular mortality were predominantly present in the nonelderly population aged < 65 years. CONCLUSIONS: In conjunction with the results of the Boruta algorithm, METS-IR demonstrated a more significant association with all-cause and cardiovascular mortality in the U.S. population compared to the other three alternative IR indexes (TyG index, TG/HDL-C and HOMA-IR), particularly evident in individuals under 65 years old.
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Biomarcadores , Glucemia , Enfermedades Cardiovasculares , Causas de Muerte , Resistencia a la Insulina , Síndrome Metabólico , Encuestas Nutricionales , Valor Predictivo de las Pruebas , Triglicéridos , Humanos , Masculino , Femenino , Enfermedades Cardiovasculares/mortalidad , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/sangre , Persona de Mediana Edad , Medición de Riesgo , Adulto , Estados Unidos/epidemiología , Biomarcadores/sangre , Anciano , Triglicéridos/sangre , Pronóstico , Glucemia/metabolismo , Factores de Tiempo , Síndrome Metabólico/mortalidad , Síndrome Metabólico/diagnóstico , Síndrome Metabólico/sangre , Síndrome Metabólico/epidemiología , HDL-Colesterol/sangre , Insulina/sangre , Factores de Riesgo de Enfermedad Cardiaca , Factores de RiesgoRESUMEN
Fibroblast activation protein-α (FAP) plays a crucial role in various physiological and pathological processes, making it a key target for cancer diagnostics and therapeutics. However, in vivo detection of FAP activity with fluorogenic probes remains challenging due to the rapid diffusion and clearance of fluorescent products from the target. Herein, we developed a self-immobilizing near-infrared (NIR) fluorogenic probe, Hcy-CF2H-PG, by introducing a difluoromethyl group to FAP substrate-caged NIR fluorophore. Upon selective activation by FAP, the fluorescence of Hcy-CF2H-PG was triggered, followed by the covalent labelling of FAP. Hcy-CF2H-PG demonstrated significantly improved sensitivity, selectivity, and long-lasting labelling capacity for FAP both in vitro and in vivo, compared to that of non-immobilized probes. This represents a noteworthy advancement in FAP detection and cancer diagnostics within complex physiological systems.
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Endopeptidasas , Colorantes Fluorescentes , Gelatinasas , Proteínas de la Membrana , Serina Endopeptidasas , Colorantes Fluorescentes/química , Animales , Humanos , Proteínas de la Membrana/análisis , Proteínas de la Membrana/metabolismo , Gelatinasas/metabolismo , Endopeptidasas/metabolismo , Serina Endopeptidasas/metabolismo , Serina Endopeptidasas/análisis , Rayos Infrarrojos , Ratones , Imagen ÓpticaRESUMEN
OBJECTIVE: Deep brain stimulation (DBS) is a promising approach for the treatment of epilepsy. However, the optimal target for DBS and underlying mechanisms are still not clear. Here, we compared the therapeutic effects of DBS on distinct septal subregions, aimed to find the precise targets of septal DBS and related mechanisms for the clinical treatment. METHODS: Assisted by behavioral test, electroencephalography (EEG) recording and analyzing, selectively neuronal manipulation and immunohistochemistry, we assessed the effects of DBS on the three septal subregions in kainic acid (KA)-induced mouse seizure model. RESULTS: DBS in the medial septum (MS) not only delayed generalized seizure (GS) development, but reduced the severity; DBS in the vertical diagonal band of Broca (VDB) only reduced the severity of GS, while DBS in the horizontal diagonal band of Broca (HDB) subregion showed no anti-seizure effect. Notably, DBS in the MS much more efficiently decreased abnormal activation of hippocampal neurons. EEG spectrum analysis indicated that DBS in the MS and VDB subregions mainly increased the basal hippocampal low-frequency (delta and theta) rhythm. Furthermore, ablation of cholinergic neurons in the MS and VDB subregions blocked the anti-seizure and EEG-modulating effects of septal DBS, suggesting the seizure-alleviating effect of DBS was dependent on local cholinergic neurons. SIGNIFICANCE: DBS in the MS and VDB, rather than HDB, attenuates hippocampal seizure by activation of cholinergic neurons-augmented hippocampal delta/theta rhythm. This may be of great therapeutic significance for the clinical treatment of epilepsy with septal DBS. PLAIN LANGUAGE SUMMARY: The optical target of deep brain stimulation in the septum is still not clear. This study demonstrated that stimulation in the medial septum and vertical diagonal band of Broca subregions, but not the horizontal diagonal band of Broca, could alleviate hippocampal seizure through cholinergic neurons-augmented hippocampal delta/theta rhythm. This study may shed light on the importance of precise regulation of deep brain stimulation therapy in treating epileptic seizures.
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Estimulación Encefálica Profunda , Electroencefalografía , Hipocampo , Convulsiones , Animales , Ratones , Convulsiones/terapia , Masculino , Ácido Kaínico , Modelos Animales de Enfermedad , Tabique del Cerebro , Ratones Endogámicos C57BL , Banda Diagonal de BrocaRESUMEN
OBJECTIVE: Fat mass and obesity-associated protein (FTO), an eraser of N 6-methyadenosine (m6A), plays oncogenic roles in various cancers. However, its role in hepatocellular carcinoma (HCC) is unclear. Furthermore, small extracellular vesicles (sEVs, or exosomes) are critical mediators of tumourigenesis and metastasis, but the relationship between FTO-mediated m6A modification and sEVs in HCC is unknown. DESIGN: The functions and mechanisms of FTO and glycoprotein non-metastatic melanoma protein B (GPNMB) in HCC progression were investigated in vitro and in vivo. Neutralising antibody of syndecan-4 (SDC4) was used to assess the significance of sEV-GPNMB. FTO inhibitor CS2 was used to examine the effects on anti-PD-1 and sorafenib treatment. RESULTS: FTO expression was upregulated in patient HCC tumours. Functionally, FTO promoted HCC cell proliferation, migration and invasion in vitro, and tumour growth and metastasis in vivo. FTO knockdown enhanced the activation and recruitment of tumour-infiltrating CD8+ T cells. Furthermore, we identified GPNMB to be a downstream target of FTO, which reduced the m6A abundance of GPNMB, hence, stabilising it from degradation by YTH N 6-methyladenosine RNA binding protein F2. Of note, GPNMB was packaged into sEVs derived from HCC cells and bound to the surface receptor SDC4 of CD8+ T cells, resulting in the inhibition of CD8+ T cell activation. A potential FTO inhibitor, CS2, suppresses the oncogenic functions of HCC cells and enhances the sensitivity of anti-PD-1 and sorafenib treatment. CONCLUSION: Targeting the FTO/m6A/GPNMB axis could significantly suppress tumour growth and metastasis, and enhance immune activation, highlighting the potential of targeting FTO signalling with effective inhibitors for HCC therapy.
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BACKGROUND & AIMS: Hepatocellular carcinoma (HCC) is a heterogeneous cancer with varying levels of liver tumor initiating or cancer stem cells in the tumors. We aimed to investigate the expression of different liver cancer stem cell (LCSC) markers in human HCCs and identify their regulatory mechanisms in stemness-related cells. METHODS: We used an unbiased, single-marker sorting approach by flow cytometry, fluorescence-activated cell sorting, and transcriptomic analyses on HCC patients' resected specimens. Knockdown approach was used, and relevant functional assays were conducted on the identified targets of interest. RESULTS: Flow cytometry on a total of 60 HCC resected specimens showed significant heterogeneity in the expression of LCSC markers, with CD24, CD13, and EpCAM mainly contributing to this heterogeneity. Concomitant expression of CD24, CD13, and EpCAM was detected in 32 HCC samples, and this was associated with advanced tumor stages. Transcriptomic sequencing on the HCC cells sorted for these individual markers identified epidermal growth factor receptor kinase substrate 8-like protein 3 (EPS8L3) as a common gene associated with the 3 markers and was functionally validated in HCC cells. Knocking down EPS8L3 suppressed the expression of all 3 markers. To search for the upstream regulation of EPS8L3, we found SP1 bound to EPS8L3 promoter to drive EPS8L3 expression. Furthermore, using Akt inhibitor MK2206, we showed that Akt signaling-driven SP1 drove the expression of the 3 LCSC markers. CONCLUSIONS: Our findings suggest that Akt signaling-driven SP1 promotes EPS8L3 expression, which is critical in maintaining the downstream expression of CD24, CD13, and EpCAM. The findings provide insight into potential LCSC-targeting therapeutic strategies.
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Photodynamic immunotherapy (PDI) is an innovative approach to cancer treatment that utilizes photodynamic therapy (PDT) and photosensitizers (PSs) to induce immunogenic cell death (ICD). However, currently most commonly used PSs have restricted capabilities to generate reactive oxygen species (ROS) via a type-II mechanism under hypoxic environments, which limits their effectiveness in PDI. To overcome this, we propose a novel approach for constructing oxygen independent PSs based on stable organic free-radical molecules. By fine-tuning the characteristics of tris(2,4,6-trichlorophenyl)-methyl (TTM) radicals through the incorporation of electron-donating moieties, we successfully found that TTMIndoOMe could produce substantial amounts of ROS even in hypoxic environments. In vitro experiments showed that TTMIndoOMe could effectively produce O2Ë-, kill tumor cells and trigger ICD. Moreover, in vivo experiments also demonstrated that TTMIndoOMe could further trigger anti-tumor immune response and exhibit a superior therapeutic effect compared with PDT alone. Our study offers a promising approach towards the development of next-generation PSs functioning efficiently even under hypoxic conditions and also paves the way for the creation of more effective PSs for PDI.
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This study investigates the genetic determinants of seed coat color and pattern variations in cowpea (Vigna unguiculata), employing a genome-wide association approach. Analyzing a mapping panel of 296 cowpea varieties with 110,000 single nucleotide polymorphisms (SNPs), we focused on eight unique coat patterns: (1) Red and (2) Cream seed; (3) White and (4) Brown/Tan seed coat; (5) Pink, (6) Black, (7) Browneye and (8) Red/Brown Holstein. Across six GWAS models (GLM, SRM, MLM, MLMM, FarmCPU from GAPIT3, and TASSEL5), 13 significant SNP markers were identified and led to the discovery of 23 candidate genes. Among these, four specific genes may play a direct role in determining seed coat pigment. These findings lay a foundational basis for future breeding programs aimed at creating cowpea varieties aligned with consumer preferences and market requirements.
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Status epilepticus (SE), a serious and often life-threatening medical emergency, is characterized by abnormally prolonged seizures. It is not effectively managed by present first-line anti-seizure medications and could readily develop into drug resistance without timely treatment. In this study, we highlight the therapeutic potential of CZL80, a small molecule that inhibits caspase-1, in SE termination and its related mechanisms. We found that delayed treatment of diazepam (0.5 h) easily induces resistance in kainic acid (KA)-induced SE. CZL80 dose-dependently terminated diazepam-resistant SE, extending the therapeutic time window to 3 h following SE, and also protected against neuronal damage. Interestingly, the effect of CZL80 on SE termination was model-dependent, as evidenced by ineffectiveness in the pilocarpine-induced SE. Further, we found that CZL80 did not terminate KA-induced SE in Caspase-1-/- mice but partially terminated SE in IL1R1-/- mice, suggesting the SE termination effect of CZL80 was dependent on the caspase-1, but not entirely through the downstream IL-1ß pathway. Furthermore, in vivo calcium fiber photometry revealed that CZL80 completely reversed the neuroinflammation-augmented glutamatergic transmission in SE. Together, our results demonstrate that caspase-1 inhibitor CZL80 terminates diazepam-resistant SE by blocking glutamatergic transmission. This may be of great therapeutic significance for the clinical treatment of refractory SE.
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Anticonvulsivantes , Caspasa 1 , Ratones Endogámicos C57BL , Estado Epiléptico , Animales , Estado Epiléptico/tratamiento farmacológico , Caspasa 1/metabolismo , Ratones , Masculino , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Ácido Kaínico/farmacología , Ratones Noqueados , Ácido Glutámico/metabolismo , Inhibidores de Caspasas/farmacología , Inhibidores de Caspasas/uso terapéutico , Diazepam/farmacología , Diazepam/uso terapéutico , Transmisión Sináptica/efectos de los fármacosRESUMEN
Two-photon excitation (TPE) microscopy with near-infrared (NIR) emission has emerged as a promising technique for deep-tissue optical imaging. Recent developments in fluorescence lifetime imaging with long-lived emission probes have further enhanced the spatial resolution and precision of fluorescence imaging, especially in complex systems with short-lived background signals. In this study, two innovative lysosome-targeting probes, Cz-NA and tCz-NA, are introduced. These probes offer a combination of advantages, including TPE (λex = 880 nm), NIR emission (λem = 650 nm), and thermally activated delayed fluorescence (TADF) with long-lived lifetimes (1.05 and 1.71 µs, respectively). These characteristics significantly improve the resolution and signal-to-noise ratio in deep-tissue imaging. By integrating an acousto-optic modulator (AOM) device with TPE microscopy, the authors successfully applied Cz-NA in two-photon excited delayed fluorescence (TPEDF) imaging to track lysosomal adaptation and immune responses to inflammation in mice. This study sheds light on the relationship between lysosome tubulation, innate immune responses, and inflammation in vivo, providing valuable insights for the development of autofluorescence-free molecular probes in the future.
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Inflamación , Lisosomas , Lisosomas/metabolismo , Animales , Ratones , Inflamación/diagnóstico por imagen , Inflamación/inmunología , Fotones , Imagen Óptica/métodos , Colorantes Fluorescentes/química , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Humanos , Ratones Endogámicos C57BLRESUMEN
Introduction: Immunotherapy has resulted in pathologic responses in hepatocellular carcinoma (HCC), but the benefits and molecular mechanisms of neoadjuvant immune checkpoint blockade are largely unknown. Methods: In this study, we evaluated the efficacy and safety of preoperative nivolumab (anti-PD-1) in patients with intermediate and locally advanced HCC and determined the molecular markers for predicting treatment response. Results: Between July 2020 and November 2021, 20 treatment-naive HCC patients with intermediate and locally advanced tumors received preoperative nivolumab at 3 mg/kg for 3 cycles prior to surgical resection. Nineteen patients underwent surgical resection on trial. Seven (36.8%) of the 19 patients had major pathologic tumor necrosis (≥60%) in the post-nivolumab resection specimens, with 3 having almost complete (>90%) tumor necrosis. The tumor necrosis was hemorrhagic and often accompanied by increased or dense immune cell infiltrate at the border of the tumors. None of the patients developed major adverse reactions contradicting hepatectomy. RNA-sequencing analysis on both pre-nivolumab tumor biopsies and post-nivolumab resected specimens showed that, in cases with major pathologic necrosis, the proportion of CD8 T cells in the HCC tissues predominantly increased after treatment. Moreover, to investigate noninvasive biomarker for nivolumab response, we evaluated the copy number variation (CNV) using target-panel sequencing on plasma cell-free DNA of the patients and derived a CNV-based anti-PD-1 score. The score correlated with the extent of tumor necrosis and was validated in a Korean patient cohort with anti-PD-1 treatment. Conclusion: Neoadjuvant nivolumab demonstrated promising clinical activity in intermediate and locally advanced HCC patients. We also identified useful noninvasive biomarker predicting responsiveness.
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Background: The tumor microenvironment of cancers has emerged as a crucial component in regulating cancer stemness and plays a pivotal role in cell-cell communication. However, the specific mechanisms underlying these phenomena remain poorly understood. Methods: We performed the single-cell RNA sequencing (scRNA-seq) on nine HBV-associated hepatocellular carcinoma (HCC) patients. The heterogeneity of the malignant cells in pathway functions, transcription factors (TFs) regulation, overall survival, stemness, as well as ligand-receptor-based intercellular communication with macrophages were characterized. The aggressive and stemness feature for the target tumor subclone was validated by the conduction of in vitro assays including sphere formation, proliferation, Annexin V apoptosis, flow cytometry, siRNA library screening assays, and multiple in vivo preclinical mouse models including mouse hepatoma cell and human HCC cell xenograft models with subcutaneous or orthotopic injection. Results: Our analysis yielded a comprehensive atlas of 31,664 cells, revealing a diverse array of malignant cell subpopulations. Notably, we identified a stemness-related subclone of HCC cells with concurrent upregulation of CD24, CD47, and ICAM1 expression that correlated with poorer overall survival. Functional characterization both in vitro and in vivo validated S100A11 as one of the top downstream mediators for tumor initiation and stemness maintenance of this subclone. Further investigation of cell-cell communication within the tumor microenvironment revealed a propensity for bi-directional crosstalk between this stemness-related subclone and tumor-associated macrophages (TAMs). Co-culture study showed that this interaction resulted in the maintenance of the expression of cancer stem cell markers and driving M2-like TAM polarization towards a pro-tumorigenic niche. We also consolidated an inverse relationship between the proportions of TAMs and tumor-infiltrating T cells. Conclusions: Our study highlighted the critical role of stemness-related cancer cell populations in driving an immunosuppressive tumor microenvironment and identified the S100A11 gene as a key mediator for stemness maintenance in HCC. Moreover, our study provides support that the maintenance of cancer stemness is more attributed to M2 polarization than the recruitment of the TAMs.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animales , Ratones , Carcinoma Hepatocelular/patología , Virus de la Hepatitis B , Neoplasias Hepáticas/patología , Macrófagos/metabolismo , Técnicas de Cocultivo , Línea Celular Tumoral , Microambiente TumoralRESUMEN
With the advent of cancer immunotherapy, some special features including delayed treatment effect, cure rate, diminishing treatment effect and crossing survival are often observed in survival analysis. They violate the proportional hazard model assumption and pose a unique challenge for the conventional trial design and analysis strategies. Many methods like cure rate model have been developed based on mixture model to incorporate some of these features. In this work, we extend the mixture model to deal with multiple non-proportional patterns and develop its geometric average hazard ratio (gAHR) to quantify the treatment effect. We further derive a sample size and power formula based on the non-centrality parameter of the log-rank test and conduct a thorough analysis of the impact of each parameter on performance. Simulation studies showed a clear advantage of our new method over the proportional hazard based calculation across different non-proportional hazard scenarios. Moreover, the mixture modeling of two real trials demonstrates how to use the prior information on the survival distribution among patients with different biomarker and early efficacy results in practice. By comparison with a simulation-based design, the new method provided a more efficient way to compute the power and sample size with high accuracy of estimation. Overall, both theoretical derivation and empirical studies demonstrate the promise of the proposed method in powering future innovative trial designs.
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Simulación por Computador , Modelos de Riesgos Proporcionales , Proyectos de Investigación , Humanos , Tamaño de la Muestra , Proyectos de Investigación/estadística & datos numéricos , Análisis de Supervivencia , Neoplasias/terapia , Neoplasias/tratamiento farmacológico , Neoplasias/mortalidad , Modelos Estadísticos , Inmunoterapia/métodosRESUMEN
A common mRNA modification is 5-methylcytosine (m5C), whose role in gene-transcript processing and cancer remains unclear. Here, we identify serine/arginine-rich splicing factor 2 (SRSF2) as a reader of m5C and impaired SRSF2 m5C binding as a potential contributor to leukemogenesis. Structurally, we identify residues involved in m5C recognition and the impact of the prevalent leukemia-associated mutation SRSF2P95H. We show that SRSF2 binding and m5C colocalize within transcripts. Furthermore, knocking down the m5C writer NSUN2 decreases mRNA m5C, reduces SRSF2 binding, and alters RNA splicing. We also show that the SRSF2P95H mutation impairs the ability of the protein to read m5C-marked mRNA, notably reducing its binding to key leukemia-related transcripts in leukemic cells. In leukemia patients, low NSUN2 expression leads to mRNA m5C hypomethylation and, combined with SRSF2P95H, predicts poor outcomes. Altogether, we highlight an unrecognized mechanistic link between epitranscriptomics and a key oncogenesis driver.
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Leucemia , Síndromes Mielodisplásicos , Neoplasias , Metilación de ARN , Factores de Empalme Serina-Arginina , Humanos , Leucemia/genética , Síndromes Mielodisplásicos/genética , Neoplasias/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/genética , Factores de Empalme Serina-Arginina/genética , Metilación de ARN/genéticaRESUMEN
As the most prominent RNA modification, N6-methyladenosine (m6 A) participates in the regulation of tumour initiation and progression. Circular RNAs (circRNAs) also play crucial roles in ubiquitous life processes. Whether circRNAs are required for m6 A regulation in renal cell carcinoma (RCC) remains unclear. Meta-analysis and bioinformatics identified that IGF2BP3 was upregulated in RCC and indicated a worse prognosis. IGF2BP3 significantly promoted RCC progression in vitro and in vivo. Mechanistically, circRARS bound to KH1-KH2 domains of IGF2BP3 to enhance m6 A modification recognition. A 12-nt sequence (GUCUUCCAGCAA) was proven to be the IGF2BP3-binding site of circRARS. Additionally, CAPN15, CD44, HMGA2, TNRC6A and ZMIZ2 were screened to be the target genes regulated by the IGF2BP3/circRARS complex in an m6 A-dependent manner. Stabiliser proteins, including HuR, Matrin3 and pAbPC1, were recruited by circRARS, thereby increasing the mRNA stability of the forementioned five target genes. Consequently, the IGF2BP3/circRARS complex facilitated the lipid accumulation of RCC cells and promoted sunitinib resistance via target genes. circRARS synergised with IGF2BP3 to facilitate m6 A recognition, thereby promoting RCC progression. Thus, IGF2BP3 could be a potential biomarker for RCC diagnosis and prognosis and a therapeutic target.
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Carcinoma de Células Renales , Neoplasias Renales , Humanos , Calpaína , Carcinoma de Células Renales/genética , Transformación Celular Neoplásica , Neoplasias Renales/genética , Proteínas Inhibidoras de STAT Activados , Metilación de ARN , ARN Circular/genéticaRESUMEN
The objective of this study was to examine the effects of dietary Chinese herbal medicine (CHM) consisting of Astragalus membranaceus (Fisch.) Bunge (AMT) and Codonopsis pilosula (Franch.) Nannf (CPO) extracts on growth performance, antioxidant capacity, immune status, and intestinal health of broiler chickens. Two groups were formed, each consisting of six replicates of 12 one-day-old healthy male 817 white feather broilers. Broilers were fed either a basal diet (CON group) or a basal diet supplemented with 500 mg/kg CHM. The trial lasted 50 days. The results showed that CHM supplementation resulted in enhanced feed efficiency and antioxidant capacity in both the serum and liver, while it reduced uric acid and endotoxin levels, as well as diamine oxidase activity (p < 0.05). Additionally, CHM treatment increased the height of jejunum villi and upregulated Claudin-1 expression in the jejunal mucosa accompanied by an increase in the mRNA levels of interleukin-6 (IL-6), interferon-γ (IFN-γ), interferon-ß (IFN-ß), tumor necrosis factor-α (TNF-α), and anti-inflammatory cytokine interleukin-10 (IL-10) (p < 0.05). The presence of dietary CHM caused an increase in the proportions of Bacteroidetes and unclassified Bacteroidales but led to a decrease in those of Firmicutes and Alistipes (p < 0.05). The composition of the jejunal mucosa microbiota was correlated with the feed conversion ratio, serum metabolites, and gene expression based on Spearman correlation analysis. The findings indicated that the consumption of dietary CHM improved the utilization of feed, increased the mRNA expression of pro-inflammatory cytokines in the jejunal mucosa, and decreased the endotoxin level and activities of diamine oxidase and lactate dehydrogenase in the serum, which could potentially be linked to changes in the gut microbiota of broiler chickens.
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The visible light communication channel has time-varying characteristics and is difficult to predict. This paper proposes an equalization algorithm based on the structure of a convolutional neural network (CNN), combining time series feature length and long short-term memory (LSTM), and adding a residual structure. It can be seen that the equalization coefficient vector of the optical channel is a time series, which can reflect the noise characteristics of the channel and has storage characteristics. The equalizer algorithm can accurately learn the complex channel characteristics and calculate the compensation coefficient according to the channel characteristics. It can also restore the original transmission signal. At the same time, this paper also examines the compensation method of the receiver in the mobile state. The long-term memory parameters of LSTM are used to represent the sequence causality in the memory channel, and CNN and residual structure are used to refine the results and improve the accuracy of the reconstruction. The simulation results show that the algorithm can effectively eliminate the influence of the fading characteristics of the visible optical channel, improve the bit error rate performance of system transmission, solve the overall problem of channel corruption, and precisely restore the original transmission signal with fast convergence speed. In addition, this method can achieve a better balance between performance and complexity compared to the traditional contention balancing method, which proves the potential and effectiveness of the proposed channel balancing method.