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1.
Genes Dev ; 38(15-16): 738-754, 2024 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-39168636

RESUMEN

Despite recent advances in therapeutic treatments, multiple myeloma (MM) remains an incurable malignancy. Epigenetic factors contribute to the initiation, progression, relapse, and clonal heterogeneity in MM, but our knowledge on epigenetic mechanisms underlying MM development is far from complete. The SAGA complex serves as a coactivator in transcription and catalyzes acetylation and deubiquitylation. Analyses of data sets in the Cancer Dependency Map Project revealed that many SAGA components are selective dependencies in MM. To define SAGA-specific functions, we focused on ADA2B, the only subunit in the lysine acetyltransferase (KAT) module that specifically functions in SAGA. Integration of RNA sequencing (RNA-seq), assay for transposase-accessible chromatin with sequencing (ATAC-seq), and cleavage under targets and release using nuclease assay (CUT&RUN) results identified pathways directly regulated by ADA2B including MTORC1 signaling and oncogenic programs driven by MYC, E2F, and MM-specific MAF. We discovered that ADA2B is recruited to MAF and MYC gene targets, and that MAF shares a majority of its targets with MYC in MM cells. Furthermore, we found that the SANT domain of ADA2B is required for interaction with both GCN5 and PCAF acetyltransferases, incorporation into SAGA, and ADA2B protein stability. Our findings uncover previously unknown SAGA KAT module-dependent mechanisms controlling MM cell growth, revealing a vulnerability that might be exploited for future development of MM therapy.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Mieloma Múltiple , Mieloma Múltiple/genética , Humanos , Línea Celular Tumoral , Proteínas Proto-Oncogénicas c-maf/genética , Proteínas Proto-Oncogénicas c-maf/metabolismo , Proteínas Proto-Oncogénicas c-myc/metabolismo , Proteínas Proto-Oncogénicas c-myc/genética , Transducción de Señal/genética
2.
Proc Natl Acad Sci U S A ; 121(27): e2320454121, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38923983

RESUMEN

Biologically detailed models of brain circuitry are challenging to build and simulate due to the large number of neurons, their complex interactions, and the many unknown physiological parameters. Simplified mathematical models are more tractable, but harder to evaluate when too far removed from neuroanatomy/physiology. We propose that a multiscale model, coarse-grained (CG) while preserving local biological details, offers the best balance between biological realism and computability. This paper presents such a model. Generally, CG models focus on the interaction between groups of neurons-here termed "pixels"-rather than individual cells. In our case, dynamics are alternately updated at intra- and interpixel scales, with one informing the other, until convergence to equilibrium is achieved on both scales. An innovation is how we exploit the underlying biology: Taking advantage of the similarity in local anatomical structures across large regions of the cortex, we model intrapixel dynamics as a single dynamical system driven by "external" inputs. These inputs vary with events external to the pixel, but their ranges can be estimated a priori. Precomputing and tabulating all potential local responses speed up the updating procedure significantly compared to direct multiscale simulation. We illustrate our methodology using a model of the primate visual cortex. Except for local neuron-to-neuron variability (necessarily lost in any CG approximation) our model reproduces various features of large-scale network models at a tiny fraction of the computational cost. These include neuronal responses as a consequence of their orientation selectivity, a primary function of visual neurons.


Asunto(s)
Modelos Neurológicos , Neuronas , Corteza Visual , Animales , Neuronas/fisiología , Corteza Visual/fisiología , Humanos , Red Nerviosa/fisiología , Corteza Cerebral/fisiología , Simulación por Computador
3.
Proc Natl Acad Sci U S A ; 120(32): e2303647120, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37523521

RESUMEN

Multimodal single-cell technologies profile multiple modalities for each cell simultaneously, enabling a more thorough characterization of cell populations. Existing dimension-reduction methods for multimodal data capture the "union of information," producing a lower-dimensional embedding that combines the information across modalities. While these tools are useful, we focus on a fundamentally different task of separating and quantifying the information among cells that is shared between the two modalities as well as unique to only one modality. Hence, we develop Tilted Canonical Correlation Analysis (Tilted-CCA), a method that decomposes a paired multimodal dataset into three lower-dimensional embeddings-one embedding captures the "intersection of information," representing the geometric relations among the cells that is common to both modalities, while the remaining two embeddings capture the "distinct information for a modality," representing the modality-specific geometric relations. We analyze single-cell multimodal datasets sequencing RNA along surface antibodies (i.e., CITE-seq) as well as RNA alongside chromatin accessibility (i.e., 10x) for blood cells and developing neurons via Tilted-CCA. These analyses show that Tilted-CCA enables meaningful visualization and quantification of the cross-modal information. Finally, Tilted-CCA's framework allows us to perform two specific downstream analyses. First, for single-cell datasets that simultaneously profile transcriptome and surface antibody markers, we show that Tilted-CCA helps design the target antibody panel to complement the transcriptome best. Second, for developmental single-cell datasets that simultaneously profile transcriptome and chromatin accessibility, we show that Tilted-CCA helps identify development-informative genes and distinguish between transient versus terminal cell types.


Asunto(s)
Algoritmos , Análisis de Correlación Canónica , Transcriptoma , Análisis de la Célula Individual/métodos
4.
Mol Ther ; 32(1): 74-83, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-37990495

RESUMEN

Recombinant adeno-associated virus (rAAV) vectors could be manufactured by plasmid transfection into human embryonic kidney 293 (HEK293) cells or baculovirus infection of Spodoptera frugiperda (Sf9) insect cells. However, systematic comparisons between these systems using large-scale, high-quality AAV vectors are lacking. rAAV from Sf9 cells (Sf9-rAAV) at 2-50 L and HEK293 cells (HEK-rAAV) at 2-200 L scales were characterized. HEK-rAAV had ∼40-fold lower yields but ∼10-fold more host cell DNA measured by droplet digital PCR and next-generation sequencing, respectively. The electron microscope observed a lower full/empty capsid ratio in HEK-rAAV (70.8%) than Sf9-rAAV (93.2%), while dynamic light scattering and high-performance liquid chromatography analysis showed that HEK-rAAV had more aggregation. Liquid chromatography tandem mass spectrometry identified different post-translational modification profiles between Sf9-rAAV and HEK-rAAV. Furthermore, Sf9-rAAV had a higher tissue culture infectious dose/viral genome than HEK-rAAV, indicating better infectivity. Additionally, Sf9-rAAV achieved higher in vitro transgene expression, as measured by ELISA. Finally, after intravitreal dosing into a mouse laser choroidal neovascularization model, Sf9-rAAV and HEK-rAAV achieved similar efficacy. Overall, this study detected notable differences in the physiochemical characteristics of HEK-rAAV and Sf9-rAAV. However, the in vitro and in vivo biological functions of the rAAV from these systems were highly comparable. Sf9-rAAV may be preferred over HEK293-rAAV for advantages in yields, full/empty ratio, scalability, and cost.


Asunto(s)
Vectores Genéticos , Riñón , Animales , Ratones , Humanos , Células HEK293 , Vectores Genéticos/genética , Transfección , Células Sf9 , Dependovirus/genética
5.
BMC Bioinformatics ; 25(1): 113, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38486150

RESUMEN

BACKGROUND: Single-cell RNA-sequencing (scRNA) datasets are becoming increasingly popular in clinical and cohort studies, but there is a lack of methods to investigate differentially expressed (DE) genes among such datasets with numerous individuals. While numerous methods exist to find DE genes for scRNA data from limited individuals, differential-expression testing for large cohorts of case and control individuals using scRNA data poses unique challenges due to substantial effects of human variation, i.e., individual-level confounding covariates that are difficult to account for in the presence of sparsely-observed genes. RESULTS: We develop the eSVD-DE, a matrix factorization that pools information across genes and removes confounding covariate effects, followed by a novel two-sample test in mean expression between case and control individuals. In general, differential testing after dimension reduction yields an inflation of Type-1 errors. However, we overcome this by testing for differences between the case and control individuals' posterior mean distributions via a hierarchical model. In previously published datasets of various biological systems, eSVD-DE has more accuracy and power compared to other DE methods typically repurposed for analyzing cohort-wide differential expression. CONCLUSIONS: eSVD-DE proposes a novel and powerful way to test for DE genes among cohorts after performing a dimension reduction. Accurate identification of differential expression on the individual level, instead of the cell level, is important for linking scRNA-seq studies to our understanding of the human population.


Asunto(s)
Perfilación de la Expresión Génica , Análisis de Expresión Génica de una Sola Célula , Humanos , Perfilación de la Expresión Génica/métodos , Programas Informáticos , Análisis de la Célula Individual/métodos
6.
Mol Cancer ; 23(1): 40, 2024 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-38383439

RESUMEN

Finding effective therapeutic targets to treat NRAS-mutated melanoma remains a challenge. Long non-coding RNAs (lncRNAs) recently emerged as essential regulators of tumorigenesis. Using a discovery approach combining experimental models and unbiased computational analysis complemented by validation in patient biospecimens, we identified a nuclear-enriched lncRNA (AC004540.4) that is upregulated in NRAS/MAPK-dependent melanoma, and that we named T-RECS. Considering potential innovative treatment strategies, we designed antisense oligonucleotides (ASOs) to target T-RECS. T-RECS ASOs reduced the growth of melanoma cells and induced apoptotic cell death, while having minimal impact on normal primary melanocytes. Mechanistically, treatment with T-RECS ASOs downregulated the activity of pro-survival kinases and reduced the protein stability of hnRNPA2/B1, a pro-oncogenic regulator of MAPK signaling. Using patient- and cell line- derived tumor xenograft mouse models, we demonstrated that systemic treatment with T-RECS ASOs significantly suppressed the growth of melanoma tumors, with no noticeable toxicity. ASO-mediated T-RECS inhibition represents a promising RNA-targeting approach to improve the outcome of MAPK pathway-activated melanoma.


Asunto(s)
Melanoma , ARN Largo no Codificante , Humanos , Ratones , Animales , Melanoma/patología , ARN Largo no Codificante/genética , Apoptosis/genética , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/uso terapéutico , Línea Celular Tumoral , Proteínas de la Membrana/genética , GTP Fosfohidrolasas/genética , GTP Fosfohidrolasas/metabolismo
7.
Mol Cancer ; 23(1): 158, 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-39103848

RESUMEN

PARP inhibitor (PARPi) therapy has transformed outcomes for patients with homologous recombination DNA repair (HRR) deficient ovarian cancers, for example those with BRCA1 or BRCA2 gene defects. Unfortunately, PARPi resistance is common. Multiple resistance mechanisms have been described, including secondary mutations that restore the HR gene reading frame. BRCA1 splice isoforms △11 and △11q can contribute to PARPi resistance by splicing out the mutation-containing exon, producing truncated, partially functional proteins. However, the clinical impacts and underlying drivers of BRCA1 exon skipping are not fully understood.We analyzed nine ovarian and breast cancer patient derived xenografts (PDX) with BRCA1 exon 11 frameshift mutations for exon skipping and therapy response, including a matched PDX pair derived from a patient pre- and post-chemotherapy/PARPi. BRCA1 exon 11 skipping was elevated in PARPi resistant PDX tumors. Two independent PDX models acquired secondary BRCA1 splice site mutations (SSMs) that drive exon skipping, confirmed using qRT-PCR, RNA sequencing, immunoblotting and minigene modelling. CRISPR/Cas9-mediated disruption of splicing functionally validated exon skipping as a mechanism of PARPi resistance. SSMs were also enriched in post-PARPi ovarian cancer patient cohorts from the ARIEL2 and ARIEL4 clinical trials.Few PARPi resistance mechanisms have been confirmed in the clinical setting. While secondary/reversion mutations typically restore a gene's reading frame, we have identified secondary mutations in patient cohorts that hijack splice sites to enhance mutation-containing exon skipping, resulting in the overexpression of BRCA1 hypomorphs, which in turn promote PARPi resistance. Thus, BRCA1 SSMs can and should be clinically monitored, along with frame-restoring secondary mutations.


Asunto(s)
Proteína BRCA1 , Resistencia a Antineoplásicos , Exones , Neoplasias Ováricas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Sitios de Empalme de ARN , Humanos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Resistencia a Antineoplásicos/genética , Proteína BRCA1/genética , Femenino , Animales , Ratones , Neoplasias Ováricas/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Mutación , Neoplasias de la Mama/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Ensayos Antitumor por Modelo de Xenoinjerto , Línea Celular Tumoral
8.
Br J Cancer ; 131(5): 820-831, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38971950

RESUMEN

BACKGROUND: Combining PARP inhibitors (PARPis) with immune checkpoint inhibitors may improve clinical outcomes in selected cancers. We evaluated rucaparib and atezolizumab in advanced gynaecological or triple-negative breast cancer (TNBC). METHODS: After identifying the recommended dose, patients with PARPi-naive BRCA-mutated or homologous recombination-deficient/loss-of-heterozygosity-high platinum-sensitive ovarian cancer or TNBC received rucaparib plus atezolizumab. Tumour biopsies were collected pre-treatment, during single-agent rucaparib run-in, and after starting combination therapy. RESULTS: The most common adverse events with rucaparib 600 mg twice daily and atezolizumab 1200 mg on Day 1 every 3 weeks were gastrointestinal effects, fatigue, liver enzyme elevations, and anaemia. Responding patients typically had BRCA-mutated tumours and higher pre-treatment tumour levels of PD-L1 and CD8 + T cells. Markers of DNA damage repair decreased during rucaparib run-in and combination treatment in responders, but typically increased in non-responders. Apoptosis signature expression showed the reverse. CD8 + T-cell activity and STING pathway activation increased during rucaparib run-in, increasing further with atezolizumab. CONCLUSIONS: In this small study, rucaparib plus atezolizumab demonstrated acceptable safety and activity in BRCA-mutated tumours. Increasing anti-tumour immunity and inflammation might be a key mechanism of action for clinical benefit from the combination, potentially guiding more targeted development of such regimens. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov (NCT03101280).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica , Indoles , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Inhibidores de Poli(ADP-Ribosa) Polimerasas/administración & dosificación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/patología , Anticuerpos Monoclonales Humanizados/administración & dosificación , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Indoles/administración & dosificación , Indoles/efectos adversos , Indoles/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Persona de Mediana Edad , Anciano , Adulto , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/patología , Neoplasias Ováricas/genética , Antígeno B7-H1 , Proteína BRCA1/genética
9.
Bioinformatics ; 39(10)2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37713474

RESUMEN

MOTIVATION: DNA-based data storage is a quickly growing field that hopes to harness the massive theoretical information density of DNA molecules to produce a competitive next-generation storage medium suitable for archival data. In recent years, many DNA-based storage system designs have been proposed. Given that no common infrastructure exists for simulating these storage systems, comparing many different designs along with many different error models is increasingly difficult. To address this challenge, we introduce FrameD, a simulation infrastructure for DNA storage systems that leverages the underlying modularity of DNA storage system designs to provide a framework to express different designs while being able to reuse common components. RESULTS: We demonstrate the utility of FrameD and the need for a common simulation platform using a case study. Our case study compares designs that utilize strand copies differently, some that align strand copies using multiple sequence alignment algorithms and others that do not. We found that the choice to include multiple sequence alignment in the pipeline is dependent on the error rate and the type of errors being injected and is not always beneficial. In addition to supporting a wide range of designs, FrameD provides the user with transparent parallelism to deal with a large number of reads from sequencing and the need for many fault injection iterations. We believe that FrameD fills a void in the tools publicly available to the DNA storage community by providing a modular and extensible framework with support for massive parallelism. As a result, it will help accelerate the design process of future DNA-based storage systems. AVAILABILITY AND IMPLEMENTATION: The source code for FrameD along with the data generated during the demonstration of FrameD is available in a public Github repository at https://github.com/dna-storage/framed, (https://dx.doi.org/10.5281/zenodo.7757762).

10.
J Clin Gastroenterol ; 58(3): 259-270, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36753456

RESUMEN

BACKGROUND: Colorectal cancer screening uptake in the United States overall has increased, but racial/ethnic disparities persist and data on colonoscopy uptake by racial/ethnic subgroups are lacking. We sought to better characterize these trends and to identify predictors of colonoscopy uptake, particularly among Asian and Hispanic subgroups. STUDY: We used data from the New York City Community Health Survey to generate estimates of up-to-date colonoscopy use in Asian and Hispanic subgroups across 6 time periods spanning 2003-2016. For each subgroup, we calculated the percent change in colonoscopy uptake over the study period and the difference in uptake compared to non-Hispanic Whites in 2015-2016. We also used multivariable logistic regression to identify predictors of colonoscopy uptake. RESULTS: All racial and ethnic subgroups with reliable estimates saw a net increase in colonoscopy uptake between 2003 and 2016. In 2015-2016, compared with non-Hispanic Whites, Puerto Ricans, Dominicans, and Central/South Americans had higher colonoscopy uptake, whereas Chinese, Asian Indians, and Mexicans had lower uptake. On multivariable analysis, age, marital status, insurance status, primary care provider, receipt of flu vaccine, frequency of exercise, and smoking status were the most consistent predictors of colonoscopy uptake (≥4 time periods). CONCLUSIONS: We found significant variation in colonoscopy uptake among Asian and Hispanic subgroups. We also identified numerous demographic, socioeconomic, and health-related predictors of colonoscopy uptake. These findings highlight the importance of examining health disparities through the lens of disaggregated racial/ethnic subgroups and have the potential to inform future public health interventions.


Asunto(s)
Asiático , Colonoscopía , Neoplasias Colorrectales , Hispánicos o Latinos , Grupos de Población en Estados Unidos , Humanos , Pueblos Caribeños/estadística & datos numéricos , Colonoscopía/estadística & datos numéricos , Colonoscopía/tendencias , Hispánicos o Latinos/etnología , Hispánicos o Latinos/estadística & datos numéricos , Ciudad de Nueva York/epidemiología , Pueblos de América del Norte/estadística & datos numéricos , Estados Unidos/epidemiología , Asiático/estadística & datos numéricos , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/epidemiología , Neoplasias Colorrectales/etnología , Detección Precoz del Cáncer/métodos , Detección Precoz del Cáncer/estadística & datos numéricos , Detección Precoz del Cáncer/tendencias , Blanco , Disparidades en Atención de Salud/etnología , Disparidades en Atención de Salud/estadística & datos numéricos , Grupos de Población en Estados Unidos/etnología , Grupos de Población en Estados Unidos/estadística & datos numéricos
11.
Mol Cell ; 62(4): 558-71, 2016 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-27132940

RESUMEN

Histone H2B monoubiquitination (H2Bub1) is centrally involved in gene regulation. The deubiquitination module (DUBm) of the SAGA complex is a major regulator of global H2Bub1 levels, and components of this DUBm are linked to both neurodegenerative diseases and cancer. Unexpectedly, we find that ablation of USP22, the enzymatic center of the DUBm, leads to a reduction, rather than an increase, in global H2bub1 levels. In contrast, depletion of non-enzymatic components, ATXN7L3 or ENY2, results in increased H2Bub1. These observations led us to discover two H2Bub1 DUBs, USP27X and USP51, which function independently of SAGA and compete with USP22 for ATXN7L3 and ENY2 for activity. Like USP22, USP51 and USP27X are required for normal cell proliferation, and their depletion suppresses tumor growth. Our results reveal that ATXN7L3 and ENY2 orchestrate activities of multiple deubiquitinating enzymes and that imbalances in these activities likely potentiate human diseases including cancer.


Asunto(s)
Neoplasias de la Mama/enzimología , Proliferación Celular , Enzimas Desubicuitinizantes/metabolismo , Histonas/metabolismo , Factores de Transcripción/metabolismo , Carga Tumoral , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Enzimas Desubicuitinizantes/genética , Endopeptidasas/genética , Endopeptidasas/metabolismo , Femenino , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genotipo , Células HEK293 , Humanos , Células MCF-7 , Ratones Endogámicos NOD , Ratones Noqueados , Ratones SCID , Fenotipo , Interferencia de ARN , Transducción de Señal , Tioléster Hidrolasas/genética , Tioléster Hidrolasas/metabolismo , Factores de Tiempo , Factores de Transcripción/genética , Transfección , Ubiquitina Tiolesterasa , Proteasas Ubiquitina-Específicas/genética , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitinación
12.
J Prosthodont ; 33(3): 273-280, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36973859

RESUMEN

PURPOSE: This in vitro study evaluated the fracture strength of screw-retained zirconia crowns connected to zirconia (Zr) and titanium (Ti) implants after undergoing a simulation of 5 years of clinical use. MATERIALS AND METHODS: Forty-eight screw-retained zirconia crowns were fabricated and assembled on four implant systems, with 12 in each group: (1) Zr implant (pure ceramic; Straumann AG) (PZr); (2) Zr implant (NobelPearl; Nobel Biocare) (NPZr); (3) Ti-Zr implant (Bone Level Roxolid; Straumann AG) (RSTiZr); (4) Ti implant (Conical Connection PMC; Nobel Biocare) (NRTi). Crowns were luted to their associated abutments using resin cement and then torqued to their assigned implants at the recommended torque value. Specimens were subjected to dynamic loading for 1,200,000 loading cycles. Fracture strength, measured in Newtons (N), was tested under static compression load using a universal testing machine at an angle of 30°. One-way ANOVA and Tukey's multiple comparisons post hoc test were used to compare the mean fracture values between the groups at a significance level of 0.05. RESULTS: The average fracture strengths for the RSTiZr and NRTi groups were 1207 ± 202 and 1073 ± 217 N, respectively, which was significantly (p < 0.0001) higher than the PZr and NPZr groups (712 ± 76 and 571.6 ± 167 N, respectively). However, no significant difference was found between the fracture strength value of RSTiZr and NRTi (p = 0.260) or PZr and NPZr (p = 0.256) groups. CONCLUSIONS: Zirconia crowns connected to Zr implants have the potential to withstand the average physiological occlusal forces which occur in the anterior and premolar regions.


Asunto(s)
Implantes Dentales , Porcelana Dental , Resistencia Flexional , Titanio , Ensayo de Materiales , Pilares Dentales , Fracaso de la Restauración Dental , Análisis del Estrés Dental , Coronas , Circonio
13.
Mol Cancer ; 22(1): 138, 2023 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-37596643

RESUMEN

The PI3K/AKT/mTOR (PAM) signaling pathway is a highly conserved signal transduction network in eukaryotic cells that promotes cell survival, cell growth, and cell cycle progression. Growth factor signalling to transcription factors in the PAM axis is highly regulated by multiple cross-interactions with several other signaling pathways, and dysregulation of signal transduction can predispose to cancer development. The PAM axis is the most frequently activated signaling pathway in human cancer and is often implicated in resistance to anticancer therapies. Dysfunction of components of this pathway such as hyperactivity of PI3K, loss of function of PTEN, and gain-of-function of AKT, are notorious drivers of treatment resistance and disease progression in cancer. In this review we highlight the major dysregulations in the PAM signaling pathway in cancer, and discuss the results of PI3K, AKT and mTOR inhibitors as monotherapy and in co-administation with other antineoplastic agents in clinical trials as a strategy for overcoming treatment resistance. Finally, the major mechanisms of resistance to PAM signaling targeted therapies, including PAM signaling in immunology and immunotherapies are also discussed.


Asunto(s)
Neoplasias , Fosfatidilinositol 3-Quinasas , Humanos , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Neoplasias/tratamiento farmacológico , Neoplasias/genética
14.
Br J Cancer ; 128(2): 255-265, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36482193

RESUMEN

BACKGROUND: Study 10, a four-part Phase 1/2 study, evaluated oral rucaparib monotherapy in patients with advanced solid tumours. Here we report the final efficacy and safety results in heavily pretreated patients with ovarian cancer who received rucaparib in Study 10 Parts 2A and 2B. METHODS: Parts 2A and 2B (Phase 2 portions) enrolled patients with relapsed, high-grade, platinum-sensitive or platinum-resistant, BRCA-mutated ovarian cancer who had received 2-4 (Part 2A) or 3-4 (Part 2B) prior chemotherapies. Patients received oral rucaparib 600 mg twice daily (starting dose). The primary endpoint was the investigator-assessed objective response rate (ORR) by RECIST v1.1. RESULTS: Fifty-four patients were enrolled: 42 in Part 2A (all had platinum-sensitive disease) and 12 in Part 2B (4 with platinum-sensitive disease; 8 with platinum-resistant disease). ORR was 59.3% (95% CI 45.0-72.4%). The median time to onset of the most common nonhaematological treatment-emergent adverse events (TEAEs) was typically early (<56 days) and was later for haematological TEAEs (53-84 days). The median duration of grade ≥3 TEAEs was ≤13 days. CONCLUSIONS: In patients with relapsed, platinum-sensitive or platinum-resistant germline BRCA-mutant high-grade ovarian cancer who had received ≥2 prior chemotherapies, rucaparib had robust antitumour activity with a safety profile consistent with prior reports. CLINICAL TRIAL REGISTRATION: NCT01482715.


Asunto(s)
Proteína BRCA2 , Neoplasias Ováricas , Humanos , Femenino , Proteína BRCA2/genética , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Carcinoma Epitelial de Ovario/genética , Platino (Metal)/uso terapéutico , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/genética
15.
Ann Surg Oncol ; 30(10): 6079-6088, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37464138

RESUMEN

BACKGROUND: Randomized trials have shown that risk-adapted intraoperative radiation therapy (IORT) after breast-conserving surgery for low-risk breast cancer patients is a safe alternative to whole-breast radiation therapy (WBRT). The risk-adapted strategy allows additional WBRT for predefined high-risk pathologic characteristics discovered on final histopathology. The greater the percentage of patients receiving WBRT, the lower the recurrence rate. The risk-adapted strategy, although important and necessary, can make IORT appear better than it actually is. METHODS: Risk-adapted IORT was used to treat 1600 breast cancers. They were analyzed by the intention-to-treat method and per protocol to better understand the contribution of IORT with and without additional whole-breast treatment. Any ipsilateral breast tumor event was considered a local recurrence. RESULTS: During a median follow-up period of 63 months, local recurrence differed significantly between the patients who received local treatment and those who received whole-breast treatment. For 1393 patients the treatment was local treatment alone. These patients experienced 79 local recurrences and a 5-year local recurrence probability of 5.95 %. For 207 patients with high-risk final histopathology, additional whole-breast treatment was administered. They experienced two local recurrences and a 5-year local recurrence probability of 0.5 % (p = 0.0009). CONCLUSIONS: Whole-breast treatment works well at reducing local recurrence, and it is a totally acceptable and necessary addition to IORT as part of a risk-adapted program. However, the more whole-breast treatment that is given, the more it dilutes the original plan of simplifying local treatment and the less we understand exactly what IORT contributes to local control as a stand-alone treatment.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Neoplasias de la Mama/patología , Mama/patología , Mastectomía Segmentaria/métodos , Terapia Combinada , Cuidados Intraoperatorios/métodos , Recurrencia , Recurrencia Local de Neoplasia/cirugía
16.
J Clin Gastroenterol ; 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37556383

RESUMEN

BACKGROUND: Asian Americans have the lowest colorectal cancer screening uptake of any racial and ethnic group in the United States. Asian Indians are among the most under-screened Asian American subgroups, but there is limited data for this population. We sought to characterize predictors of colonoscopy use among Asian Indians in New York City. METHODS: Using 2003 to 2016 data from the New York City Community Health Survey, we identified all Asian Indian participants aged 50 years or older. We examined the association between sociodemographic and medical factors and up-to-date colonoscopy use (defined as colonoscopy within the last 10 y) using logistic regression over 4 time periods: 2003 to 2008, 2009 to 2012, 2013 to 2014, 2015 to 2016. RESULTS: On multivariable analysis, language, age, income, recent exercise, body mass index, and influenza vaccination were associated with colonoscopy uptake in 1 time period. Compared with participants who preferred English, those who preferred an Indian language were less likely to have been up-to-date in 2013 to 2014 (odds ratio 0.12, 95% CI 0.02-0.66). Individuals older than 65 years were more likely than those aged 50 to 64 years to have received a colonoscopy in 2009 to 2012 (odds ratio 3.91, 95% CI 1.49-10.24), although the risk estimates were also consistently positive in the other 3 time periods. CONCLUSIONS: Among Asian Indians living in New York City, several demographic, socioeconomic, and health-related characteristics predict colonoscopy use. These findings highlight the importance of examining determinants of colonoscopy uptake in this understudied population to inform future public health interventions.

17.
Mikrochim Acta ; 191(1): 46, 2023 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-38129631

RESUMEN

Immobilization of proteins and enzymes on solid supports has been utilized in a variety of applications, from improved protein stability on supported catalysts in industrial processes to fabrication of biosensors, biochips, and microdevices. A critical requirement for these applications is facile yet stable covalent conjugation between the immobilized and fully active protein and the solid support to produce stable, highly bio-active conjugates. Here, we report functionalization of solid surfaces (gold nanoparticles and magnetic beads) with bio-active proteins using site-specific and biorthogonal labeling and azide-alkyne cycloaddition, a click chemistry. Specifically, we recombinantly express and selectively label calcium-dependent proteins, calmodulin and calcineurin, and cAMP-dependent protein kinase A (PKA) with N-terminal azide-tags for efficient conjugation to nanoparticles and magnetic beads. We successfully immobilized the proteins on to the solid supports directly from the cell lysate with click chemistry, forgoing the step of purification. This approach is optimized to yield low particle aggregation and high levels of protein activity post-conjugation. The entire process enables streamlined workflows for bioconjugation and highly active conjugated proteins.


Asunto(s)
Azidas , Nanopartículas del Metal , Oro , Proteínas/metabolismo , Catálisis
18.
Lancet Oncol ; 23(4): 465-478, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35298906

RESUMEN

BACKGROUND: Few prospective studies have compared poly(adenosine diphosphate-ribose) polymerase (PARP) inhibitors to chemotherapy for the treatment of BRCA1-mutated or BRCA2-mutated ovarian carcinoma. We aimed to assess rucaparib versus platinum-based and non-platinum-based chemotherapy in this setting. METHODS: In this open-label, randomised, controlled, phase 3 study (ARIEL4), conducted in 64 hospitals and cancer centres across 12 countries (Brazil, Canada, Czech Republic, Hungary, Israel, Italy, Poland, Russia, Spain, Ukraine, the UK, and the USA), we recruited patients aged 18 years and older with BRCA1-mutated or BRCA2-mutated ovarian carcinoma, with an Eastern Cooperative Oncology Group performance status of 0 or 1, and who had received two or more previous chemotherapy regimens. Eligible patients were randomly assigned (2:1), using an interactive response technology and block randomisation (block size of six) and stratified by progression-free interval after the most recent platinum-containing therapy, to oral rucaparib (600 mg twice daily) or chemotherapy (administered per institutional guidelines). Patients assigned to the chemotherapy group with platinum-resistant or partially platinum-sensitive disease were given paclitaxel (starting dose 60-80 mg/m2 on days 1, 8, and 15); those with fully platinum-sensitive disease received platinum-based chemotherapy (single-agent cisplatin or carboplatin, or platinum-doublet chemotherapy). Patients were treated in 21-day or 28-day cycles. The primary endpoint was investigator-assessed progression-free survival, assessed in the efficacy population (all randomly assigned patients with deleterious BRCA1 or BRCA2 mutations without reversion mutations), and then in the intention-to-treat population (all randomly assigned patients). Safety was assessed in all patients who received at least one dose of assigned study treatment. This study is registered with ClinicalTrials.gov, NCT02855944; enrolment is complete, and the study is ongoing. FINDINGS: Between March 1, 2017, and Sept 24, 2020, 930 patients were screened, of whom 349 eligible patients were randomly assigned to rucaparib (n=233) or chemotherapy (n=116). Median age was 58 years (IQR 52-64) and 332 (95%) patients were White. As of data cutoff (Sept 30, 2020), median follow-up was 25·0 months (IQR 13·8-32·5). In the efficacy population (220 patients in the rucaparib group; 105 in the chemotherapy group), median progression-free survival was 7·4 months (95% CI 7·3-9·1) in the rucaparib group versus 5·7 months (5·5-7·3) in the chemotherapy group (hazard ratio [HR] 0·64 [95% CI 0·49-0·84]; p=0·0010). In the intention-to-treat population (233 in the rucaparib group; 116 in the chemotherapy group), median progression-free survival was 7·4 months (95% CI 6·7-7·9) in the rucaparib group versus 5·7 months (5·5-6·7) in the chemotherapy group (HR 0·67 [95% CI 0·52-0·86]; p=0·0017). Most treatment-emergent adverse events were grade 1 or 2. The most common grade 3 or worse treatment-emergent adverse event was anaemia or decreased haemoglobin (in 52 [22%] of 232 patients in the rucaparib group vs six [5%] of 113 in the chemotherapy group). Serious treatment-emergent adverse events occurred in 62 (27%) patients in the rucaparib group versus 13 (12%) in the chemotherapy group; serious adverse events considered related to treatment by the investigator occurred in 32 (14%) patients in the rucaparib group and six (5%) in the chemotherapy group. Three deaths were considered to be potentially related to rucaparib (one due to cardiac disorder, one due to myelodysplastic syndrome, and one with an unconfirmed cause). INTERPRETATION: Results from the ARIEL4 study support rucaparib as an alternative treatment option to chemotherapy for patients with relapsed, BRCA1-mutated or BRCA2-mutated ovarian carcinoma. FUNDING: Clovis Oncology.


Asunto(s)
Neoplasias Ováricas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Adolescente , Proteína BRCA1/genética , Proteína BRCA2/genética , Humanos , Indoles , Persona de Mediana Edad , Mutación , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/efectos adversos , Estudios Prospectivos
19.
Development ; 146(4)2019 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-30718289

RESUMEN

USP22, a component of the SAGA complex, is overexpressed in highly aggressive cancers, but the normal functions of this deubiquitinase are not well defined. We determined that loss of USP22 in mice results in embryonic lethality due to defects in extra-embryonic placental tissues and failure to establish proper vascular interactions with the maternal circulatory system. These phenotypes arise from abnormal gene expression patterns that reflect defective kinase signaling, including TGFß and several receptor tyrosine kinase pathways. USP22 deletion in endothelial cells and pericytes that are induced from embryonic stem cells also hinders these signaling cascades, with detrimental effects on cell survival and differentiation as well as on the ability to form vessels. Our findings provide new insights into the functions of USP22 during development that may offer clues to its role in disease states.


Asunto(s)
Endopeptidasas/metabolismo , Regulación del Desarrollo de la Expresión Génica , Placenta/metabolismo , Transducción de Señal , Animales , Sistema Cardiovascular/metabolismo , Diferenciación Celular , Supervivencia Celular , Membrana Corioalantoides/metabolismo , Oído Interno/embriología , Células Madre Embrionarias/metabolismo , Células Endoteliales/metabolismo , Femenino , Expresión Génica , Perfilación de la Expresión Génica , Ratones , Fenotipo , Embarazo , Procesamiento Proteico-Postraduccional , Factores de Tiempo , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Ubiquitina Tiolesterasa
20.
Radiology ; 305(2): 419-428, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35852431

RESUMEN

Background Prostate-specific membrane antigen (PSMA) PET is standard for newly diagnosed high-risk and biochemically recurrent (BCR) prostate cancer. Although studies suggest high specificity of 2-(3-{1-carboxy-5-[(6-[(18)F]fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid (DCFPyL) for targeting PSMA, false-positive findings have been identified and most studies lack histologic confirmation of malignancy. Purpose To estimate the positive predictive value (PPV) of DCFPyL PET/CT by providing histopathologic proof for DCFPyL-avid lesions suspected of being distant metastases at initial diagnosis and recurrence in BCR prostate cancer. Materials and Methods In this prospective trial, men with newly diagnosed high-risk prostate cancer (sample 1) or BCR prostate cancer and negative findings at conventional CT and/or bone scanning (sample 2) were enrolled between January and December 2021. All men underwent DCFPyL PET/CT. Suspected distant metastases and/or recurrences were biopsied. PPV was calculated. Results A total of 92 men with newly diagnosed prostate cancer (median age, 70 years; IQR, 64-75 years) (sample 1) and 92 men with BCR prostate cancer (median age, 71 years; IQR, 66-75 years) (sample 2) were enrolled. In sample 1, 25 of the 92 men (27%) demonstrated DCFPyL-avid lesions suspicious for distant metastases. Biopsy was performed in 23 of the 25 men (92%), with 17 of the 23 (74%) biopsies positive for malignancy and six (26%) benign. Of the six benign biopsies, three were solitary rib foci and three were solitary pelvic bone foci. In sample 2, 57 of the 92 men (62%) demonstrated DCFPyL-avid lesions suspicious for recurrence. Biopsy was performed in 37 of the 57 men (65%), with 33 of the 37 (89%) biopsies positive for malignancy and four (11%) benign. Of the four benign biopsies, two were subcentimeter pelvic nodes and/or nodules, one was a rib, and one was a pelvic bone focus. Conclusion PET/CT with 2-(3-{1-carboxy-5-[(6-[(18)F]fluoro-pyridine-3-carbonyl)-amino]-pentyl}-ureido)-pentanedioic acid (DCFPyL) had a high biopsy-proven positive predictive value for distant metastases in newly diagnosed prostate cancer (74%) and for recurrence sites in men with biochemical recurrence (89%). However, there were DCFPyL-avid false-positive findings (particularly in ribs and pelvic bones). Solitary DCFPyL avidity in these locations should not be presumed as malignant. Biopsy may still be needed prior to therapy decisions. ClinicalTrials.gov registration no. NCT04700332 © RSNA, 2022 See also the editorial by Zukotynski and Kuo in this issue.


Asunto(s)
Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias de la Próstata , Anciano , Humanos , Masculino , Lisina , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Estudios Prospectivos , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/patología , Piridinas , Tomografía Computarizada por Rayos X , Urea , Persona de Mediana Edad
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