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1.
Front Immunol ; 15: 1351739, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38690281

RESUMEN

Background: A useful clinical biomarker requires not only association but also a consistent temporal relationship. For instance, chemotherapy-induced neutropenia and epidermal growth-factor inhibitor-related acneiform rash both occur within weeks of treatment initiation, thereby providing information prior to efficacy assessment. Although immune checkpoint inhibitor (ICI)-associated immune-related adverse events (irAE) have been associated with therapeutic benefit, irAE may have delayed and highly variable onset. To determine whether ICI efficacy and irAE could serve as clinically useful biomarkers for predicting each other, we determined the temporal relationship between initial efficacy assessment and irAE onset in a diverse population treated with ICI. Methods: Using two-sided Fisher exact and Cochran-Armitage tests, we determined the relative timing of initial efficacy assessment and irAE occurrence in a cohort of 155 ICI-treated patients (median age 68 years, 40% women). Results: Initial efficacy assessment was performed a median of 50 days [interquartile range (IQR) 39-59 days] after ICI initiation; median time to any irAE was 77 days (IQR 28-145 days) after ICI initiation. Median time to first irAE was 42 days (IQR 20-88 days). Overall, 58% of any irAE and 47% of first irAE occurred after initial efficacy assessment. For clinically significant (grade ≥2) irAE, 60% of any and 53% of first occurred after initial efficacy assessment. The likelihood of any future irAE did not differ according to response (45% for complete or partial response vs. 47% for other cases; P=1). In landmark analyses controlling for clinical and toxicity follow-up, patients demonstrating greater tumor shrinkage at initial efficacy assessment were more likely to develop future grade ≥2 (P=0.05) and multi-organ (P=0.02) irAE. Conclusions: In contrast to that seen with chemotherapy and molecularly targeted therapies, the temporal relationship between ICI efficacy and toxicity is complex and bidirectional. In practice, neither parameter can be routinely relied on as a clinical biomarker to predict the other.


Asunto(s)
Biomarcadores , Inhibidores de Puntos de Control Inmunológico , Neoplasias , Humanos , Femenino , Masculino , Anciano , Inhibidores de Puntos de Control Inmunológico/efectos adversos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Persona de Mediana Edad , Neoplasias/tratamiento farmacológico , Neoplasias/inmunología , Neoplasias/terapia , Inmunoterapia/efectos adversos , Inmunoterapia/métodos , Resultado del Tratamiento , Factores de Tiempo
2.
Cancer Discov ; 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38591846

RESUMEN

Cancer cells exhibit phenotypical plasticity and epigenetic reprogramming, which allows them to evade lineage-dependent targeted treatments by adopting lineage plasticity. The underlying mechanisms by which cancer cells exploit the epigenetic regulatory machinery to acquire lineage plasticity and therapy resistance remain poorly understood. We identified Zinc Finger Protein 397 (ZNF397) as a bona fide coactivator of the androgen receptor (AR), essential for the transcriptional program governing AR-driven luminal lineage. ZNF397 deficiency facilitates the transition of cancer cell from an AR-driven luminal lineage to a Ten-Eleven Translocation 2 (TET2)-driven lineage plastic state, ultimately promoting resistance to therapies inhibiting AR signaling. Intriguingly, our findings indicate that a TET2 inhibitor can eliminate the resistance to AR targeted therapies in ZNF397-deficient tumors. These insights uncover a novel mechanism through which prostate cancer acquires lineage plasticity via epigenetic rewiring and offer promising implications for clinical interventions designed to overcome therapy resistance dictated by lineage plasticity.

4.
Bioinformatics ; 40(1)2024 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-38237909

RESUMEN

MOTIVATION: Non-informative or diffuse prior distributions are widely employed in Bayesian data analysis to maintain objectivity. However, when meaningful prior information exists and can be identified, using an informative prior distribution to accurately reflect current knowledge may lead to superior outcomes and great efficiency. RESULTS: We propose MetaNorm, a Bayesian algorithm for normalizing NanoString nCounter gene expression data. MetaNorm is based on RCRnorm, a powerful method designed under an integrated series of hierarchical models that allow various sources of error to be explained by different types of probes in the nCounter system. However, a lack of accurate prior information, weak computational efficiency, and instability of estimates that sometimes occur weakens the approach despite its impressive performance. MetaNorm employs priors carefully constructed from a rigorous meta-analysis to leverage information from large public data. Combined with additional algorithmic enhancements, MetaNorm improves RCRnorm by yielding more stable estimation of normalized values, better convergence diagnostics and superior computational efficiency. AVAILABILITY AND IMPLEMENTATION: R Code for replicating the meta-analysis and the normalization function can be found at github.com/jbarth216/MetaNorm.


Asunto(s)
Algoritmos , Análisis de Datos , Teorema de Bayes
5.
Oncogene ; 43(4): 265-280, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38030789

RESUMEN

Prostate cancer (PCa) is primarily driven by aberrant Androgen Receptor (AR) signaling. Although there has been substantial advancement in antiandrogen therapies, resistance to these treatments remains a significant obstacle, often marked by continuous or enhanced AR signaling in resistant tumors. While the dysregulation of the ubiquitination-based protein degradation process is instrumental in the accumulation of oncogenic proteins, including AR, the molecular mechanism of ubiquitination-driven AR degradation remains largely undefined. We identified UBE2J1 as the critical E2 ubiquitin-conjugating enzyme responsible for guiding AR ubiquitination and eventual degradation. The absence of UBE2J1, found in 5-15% of PCa patients, results in disrupted AR ubiquitination and degradation. This disruption leads to an accumulation of AR proteins, promoting resistance to antiandrogen treatments. By employing a ubiquitination-based AR degrader to adeptly restore AR ubiquitination, we reestablished AR degradation and inhibited the proliferation of antiandrogen-resistant PCa tumors. These findings underscore the fundamental role of UBE2J1 in AR degradation and illuminate an uncharted mechanism through which PCa maintains heightened AR protein levels, fostering resistance to antiandrogen therapies.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Neoplasias de la Próstata , Proteolisis , Receptores Androgénicos , Enzimas Ubiquitina-Conjugadoras , Humanos , Masculino , Antagonistas de Andrógenos/farmacología , Andrógenos , Línea Celular Tumoral , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/metabolismo , Receptores Androgénicos/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo
6.
bioRxiv ; 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38105939

RESUMEN

Profiling the binding of T cell receptors (TCRs) of T cells to antigenic peptides presented by MHC proteins is one of the most important unsolved problems in modern immunology. Experimental methods to probe TCR-antigen interactions are slow, labor-intensive, costly, and yield moderate throughput. To address this problem, we developed pMTnet-omni, an Artificial Intelligence (AI) system based on hybrid protein sequence and structure information, to predict the pairing of TCRs of αß T cells with peptide-MHC complexes (pMHCs). pMTnet-omni is capable of handling peptides presented by both class I and II pMHCs, and capable of handling both human and mouse TCR-pMHC pairs, through information sharing enabled this hybrid design. pMTnet-omni achieves a high overall Area Under the Curve of Receiver Operator Characteristics (AUROC) of 0.888, which surpasses competing tools by a large margin. We showed that pMTnet-omni can distinguish binding affinity of TCRs with similar sequences. Across a range of datasets from various biological contexts, pMTnet-omni characterized the longitudinal evolution and spatial heterogeneity of TCR-pMHC interactions and their functional impact. We successfully developed a biomarker based on pMTnet-omni for predicting immune-related adverse events of immune checkpoint inhibitor (ICI) treatment in a cohort of 57 ICI-treated patients. pMTnet-omni represents a major advance towards developing a clinically usable AI system for TCR-pMHC pairing prediction that can aid the design and implementation of TCR-based immunotherapeutics.

7.
bioRxiv ; 2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37961351

RESUMEN

Cancer cells exhibit phenotypical plasticity and epigenetic reprogramming, which allows them to evade lineage-dependent targeted treatments by adopting lineage plasticity. The underlying mechanisms by which cancer cells exploit the epigenetic regulatory machinery to acquire lineage plasticity and therapy resistance remain poorly understood. We identified Zinc Finger Protein 397 (ZNF397) as a bona fide co-activator of the androgen receptor (AR), essential for the transcriptional program governing AR-driven luminal lineage. ZNF397 deficiency facilitates the transition of cancer cell from an AR-driven luminal lineage to a Ten-Eleven Translocation 2 (TET2)-driven lineage plastic state, ultimately promoting resistance to therapies inhibiting AR signaling. Intriguingly, our findings indicate that TET2 inhibitor can eliminate the AR targeted therapies resistance in ZNF397-deficient tumors. These insights uncover a novel mechanism through which prostate and breast cancers acquire lineage plasticity via epigenetic rewiring and offer promising implications for clinical interventions designed to overcome therapy resistance dictated by lineage plasticity. Statement of Significance: This study reveals a novel epigenetic mechanism regulating tumor lineage plasticity and therapy response, enhances understanding of drug resistance and unveils a new therapeutic strategy for prostate cancer and other malignancies. Our findings also illuminate TET2's oncogenic role and mechanistically connect TET2-driven epigenetic rewiring to lineage plasticity and therapy resistance.

8.
Genome Biol ; 24(1): 262, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-37974276

RESUMEN

Recently, many analysis tools have been devised to offer insights into data generated via cytometry by time-of-flight (CyTOF). However, objective evaluations of these methods remain absent as most evaluations are conducted against real data where the ground truth is generally unknown. In this paper, we develop Cytomulate, a reproducible and accurate simulation algorithm of CyTOF data, which could serve as a foundation for future method development and evaluation. We demonstrate that Cytomulate can capture various characteristics of CyTOF data and is superior in learning overall data distributions than single-cell RNA-seq-oriented methods such as scDesign2, Splatter, and generative models like LAMBDA.


Asunto(s)
Algoritmos , Análisis de la Célula Individual , Simulación por Computador , Análisis de la Célula Individual/métodos , Citometría de Flujo/métodos
9.
Cancer Cell ; 41(8): 1427-1449.e12, 2023 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-37478850

RESUMEN

Tumor mutational burden and heterogeneity has been suggested to fuel resistance to many targeted therapies. The cytosine deaminase APOBEC proteins have been implicated in the mutational signatures of more than 70% of human cancers. However, the mechanism underlying how cancer cells hijack the APOBEC mediated mutagenesis machinery to promote tumor heterogeneity, and thereby foster therapy resistance remains unclear. We identify SYNCRIP as an endogenous molecular brake which suppresses APOBEC-driven mutagenesis in prostate cancer (PCa). Overactivated APOBEC3B, in SYNCRIP-deficient PCa cells, is a key mutator, representing the molecular source of driver mutations in some frequently mutated genes in PCa, including FOXA1, EP300. Functional screening identifies eight crucial drivers for androgen receptor (AR)-targeted therapy resistance in PCa that are mutated by APOBEC3B: BRD7, CBX8, EP300, FOXA1, HDAC5, HSF4, STAT3, and AR. These results uncover a cell-intrinsic mechanism that unleashes APOBEC-driven mutagenesis, which plays a significant role in conferring AR-targeted therapy resistance in PCa.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Mutagénesis , Mutación , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/genética , Receptores Androgénicos/genética , Proteínas Cromosómicas no Histona , Ribonucleoproteínas Nucleares Heterogéneas , Citidina Desaminasa , Antígenos de Histocompatibilidad Menor , Complejo Represivo Polycomb 1
10.
Transl Oncol ; 34: 101689, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37285748

RESUMEN

INTRODUCTION: Preclinical studies have demonstrated the ability of radiation therapy (RT) to augment immune response and tumor control by immune checkpoint inhibitors (ICI). However, numerous clinical trials combining RT and ICI have yielded relatively disappointing results. To improve understanding of optimal use of these therapies, we assessed systemic immune effects of prior RT in patients receiving ICI. METHODS AND MATERIALS: Pre- and post-ICI blood samples were collected from patients enrolled in a prospective immunotherapy biospecimen protocol. Mutiplex panels of 40 cytokines and 120 autoantibodies (Ab) were analyzed. We identified differences in these parameters according to receipt, timing, and type of prior RT. We calculated P values using the Pearson product-moment correlation coefficient and false discovery rate (FDR) using the Benjamini-Hochberg Procedure. RESULTS: Among 277 total patients, 69 (25%) received RT in the 6 months prior to ICI initiation. Among RT-treated patients, 23 (33%) received stereotactic RT, and 33 (48%) received curative intent RT. There was no significant difference in demographics or type of immunotherapy between patients according to prior RT exposure. Baseline complement C8 Ab and MIP-1d/CCL15 were significantly higher among patients with prior RT. For MIP-1d/CCL15, only prior stereotactic RT was associated with significant differences. CONCLUSIONS: Prior RT is associated with few changes in systemic immune parameters in patients receiving ICI. The underlying mechanisms and optimal approach to harnessing the potential synergy of RT and ICI require further prospective clinical investigation.

11.
Nat Commun ; 14(1): 1836, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-37005472

RESUMEN

While experimental and informatic techniques around single cell sequencing (scRNA-seq) are advanced, research around mass cytometry (CyTOF) data analysis has severely lagged behind. CyTOF data are notably different from scRNA-seq data in many aspects. This calls for the evaluation and development of computational methods specific for CyTOF data. Dimension reduction (DR) is one of the critical steps of single cell data analysis. Here, we benchmark the performances of 21 DR methods on 110 real and 425 synthetic CyTOF samples. We find that less well-known methods like SAUCIE, SQuaD-MDS, and scvis are the overall best performers. In particular, SAUCIE and scvis are well balanced, SQuaD-MDS excels at structure preservation, whereas UMAP has great downstream analysis performance. We also find that t-SNE (along with SQuad-MDS/t-SNE Hybrid) possesses the best local structure preservation. Nevertheless, there is a high level of complementarity between these tools, so the choice of method should depend on the underlying data structure and the analytical needs.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de la Célula Individual , Perfilación de la Expresión Génica/métodos , Análisis de Secuencia de ARN/métodos , Análisis de la Célula Individual/métodos , Algoritmos , Análisis por Conglomerados
12.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 39(2): 153-158, 2023 Feb.
Artículo en Chino | MEDLINE | ID: mdl-36872434

RESUMEN

Objective To investigate the effect and mechanism of Mongolian medicine Heisuga-25 on Alzheimer's disease (AD) mice. Methods Six month old SAMP8 mice were divided into model group, Heisuga-25 [360 mg/(kg.d), 90 mg/(kg.d)] treatment group, and donepezil control group[0.92 mg/(kg.d)], with 15 mice in each group. Another 15 6-month-old normal aging SAMR1 mice were selected as blank control group. The mice in the model group and blank control group were fed with normal saline, and the other groups were gavaged according to the dosage. All groups were gavaged once a day for 15 days. From Day 1 to Day 5 after administration, three mice in each group were taken and Morris water maze test was been used to detect the escape latency, times for crossing the platform and the residence time were detected. Nissl staining was used to observe the number of Nissl bodies. Western blot analysis and immunohistochemistry were used to detect the expression of microtubule associated protein 2 (MAP-2) and low molecular weight neurofilament protein (NF-L). ELISA was used to detect the contents of acetylcholine (ACh), 5-hydroxytryptamine (5-HT), norepinephrine (NE) and dopamine (DA) in cortex and hippocampus of mice. Results Compared with the blank control group, the escape latency was significantly prolonged, while the model group showed a decrease in the number of crossing the platform, residence time, Nissl bodies, and the protein expression of MAP-2 and NF-L. Compared with the model group, Heisuga-25 administration group exhibited an increase in the number of crossing the platform and residence time, Nissl bodies, and the protein expression of MAP-2 and NF-L, but a shortened escape latency. The effect of high-dose groupHeisuga-25 [360 mg /(kg.d)] on the above indexes was more obvious. Compared with the blank control group, the contents of ACh, NE, DA and 5-HT in hippocampus and cortex were decreased in the model group. Compared with the model group, the low-dose group, high-dose group and donepezil control group all observed an increase in the contents of ACh, NE, DA and 5-HT. Conclusion Mongolian medicine Heisuga-25 can improve learning and memory by protecting the neural function of AD model mice, which may be accounted for up-regulation of neuronal skeleton protein expression and increased content of neurotransmitters.


Asunto(s)
Enfermedad de Alzheimer , Animales , Ratones , Donepezilo , Medicina Tradicional Mongoliana , Serotonina , Acetilcolina , Dopamina , Neurotransmisores
13.
Int J Biol Macromol ; 123: 569-575, 2019 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-30439436

RESUMEN

The starch/polyvinyl alcohol/graphene oxide composite film was prepared by casting method by adding GO to starch/PVA matrix. The effects of GO with different concentrations on the performance of the composite film were studied. With the increase of GO concentration, the thickness increased, the tensile strength increased first and then decreased. When the concentration of GO reached 2 mg/ml, the tensile strength was 25.28 MPa reaching the maximum. The increase of GO concentration caused the enhancement of film's moisture resistance. Through FTIR, SEM and TGA analysis, it was found that the addition of GO did not change the composition of the film, but it could change the phenomenon of matrix agglomeration and improve the thermal stability of the film. The preparation of composite films by adding GO could improve the properties, expand the application of nanomaterials in the food packaging field, and expand the research of biodegradable composite films.


Asunto(s)
Grafito/química , Nanocompuestos/química , Almidón/química , Embalaje de Alimentos , Alcohol Polivinílico/química , Resistencia a la Tracción
14.
Medicine (Baltimore) ; 97(51): e13526, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30572452

RESUMEN

BACKGROUND: Influenza, measles, and mumps are common viral infectious diseases in Mongolia. The traditional Mongolian medicine (TMM) classified them as warm disease, and still plays a major role in the diagnoses and treatments. METHODS: To interpret the connotation of the complex theoretical system in TMM with scientific technique, in this study, a high throughput mass spectrometry was used to identify potential protein markers of TMM symptom types. Fifty venous blood samples were drawn from influenza, measles and mumps patients. Differential proteins between samples of patients diagnosed as immature and mature heat in TMM were detected by mass spectrometry. RESULTS: After proteomics analysis, 1500 proteins and 7619 polypeptides were identified and 1323 in total showed differential expression between those 2 symptom types; then enrichment analysis of the differentially expressed proteins revealed the significant biological functions related to the differentially expressed proteins, including cardiomyopathy, several bacterial and parasitic infections, bacterial invasion of epithelial cells, insulin signaling pathway, and regulation of actin cytoskeleton. The network analysis showed that FBP2 and Talin-1 were critical points and might determine the evolution directions of TMM warm disease symptom. CONCLUSIONS: This study suggests that the identified core differential proteins may be regarded as potential biomarkers, and benefit to evaluate the evolutionary tendency of TMM warm disease symptoms.


Asunto(s)
Fructosa-Bifosfatasa/sangre , Gripe Humana/diagnóstico , Sarampión/diagnóstico , Medicina Tradicional Mongoliana/métodos , Paperas/diagnóstico , Talina/sangre , Adolescente , Adulto , Anciano , Biomarcadores/sangre , Ensayos Analíticos de Alto Rendimiento , Humanos , Espectrometría de Masas , Persona de Mediana Edad , Proteómica , Adulto Joven
15.
Polymers (Basel) ; 9(3)2017 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-30970782

RESUMEN

Ternary blend films were prepared with different ratios of starch/polyvinyl alcohol (PVA)/citric acid. The films were characterized by field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis, as well as Fourier transform infrared (FTIR) analysis. The influence of different ratios of starch/polyvinyl alcohol (PVA)/citric acid and different drying times on the performance properties, transparency, tensile strength (TS), water vapor permeability (WVP), water solubility (WS), color difference (ΔE), and antimicrobial activity of the ternary blends films were investigated. The starch/polyvinyl alcohol/citric acid (S/P/C1:1:0, S/P/C3:1:0.08, and S/P/C3:3:0.08) films were all highly transparent. The S/P/C3:3:0.08 had a 54.31 times water-holding capacity of its own weight and its mechanical tensile strength was 46.45 MPa. In addition, its surface had good uniformity and compactness. The S/P/C3:1:0.08 and S/P/C3:3:0.08 showed strong antimicrobial activity to Listeria monocytogenes and Escherichia coli, which were the food-borne pathogenic bacteria used. The freshness test results of fresh figs showed that all of the blends prevented the formation of condensed water on the surface of the film, and the S/P/C3:1:0.08 and S/P/C3:3:0.08 prevented the deterioration of figs during storage. The films can be used as an active food packaging system due to their strong antibacterial effect.

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