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1.
Cell ; 184(22): 5577-5592.e18, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-34644529

RESUMEN

Intratumoral heterogeneity is a critical frontier in understanding how the tumor microenvironment (TME) propels malignant progression. Here, we deconvolute the human pancreatic TME through large-scale integration of histology-guided regional multiOMICs with clinical data and patient-derived preclinical models. We discover "subTMEs," histologically definable tissue states anchored in fibroblast plasticity, with regional relationships to tumor immunity, subtypes, differentiation, and treatment response. "Reactive" subTMEs rich in complex but functionally coordinated fibroblast communities were immune hot and inhabited by aggressive tumor cell phenotypes. The matrix-rich "deserted" subTMEs harbored fewer activated fibroblasts and tumor-suppressive features yet were markedly chemoprotective and enriched upon chemotherapy. SubTMEs originated in fibroblast differentiation trajectories, and transitory states were notable both in single-cell transcriptomics and in situ. The intratumoral co-occurrence of subTMEs produced patient-specific phenotypic and computationally predictable heterogeneity tightly linked to malignant biology. Therefore, heterogeneity within the plentiful, notorious pancreatic TME is not random but marks fundamental tissue organizational units.


Asunto(s)
Neoplasias Pancreáticas/patología , Microambiente Tumoral , Adenocarcinoma/genética , Adenocarcinoma/inmunología , Adenocarcinoma/patología , Fibroblastos Asociados al Cáncer/patología , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/inmunología , Carcinoma Ductal Pancreático/patología , Diferenciación Celular , Proliferación Celular , Epitelio/patología , Matriz Extracelular/metabolismo , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/inmunología , Fenotipo , Células del Estroma/patología , Análisis de Supervivencia , Microambiente Tumoral/inmunología
2.
Faraday Discuss ; 245(0): 164-180, 2023 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-37334658

RESUMEN

We report Atacama Large Millimeter/submillimeter Array (ALMA) high-angular resolution (∼50 au) observations of the binary system SVS13-A. More specifically, we analyse deuterated water (HDO) and sulfur dioxide (SO2) emission. The molecular emission is associated with both the components of the binary system, VLA4A and VLA4B. The spatial distribution is compared to that of formamide (NH2CHO), previously analysed in the system. Deuterated water shows an additional emitting component spatially coincident with the dust-accretion streamer, at a distance ≥120 au from the protostars, and at blue-shifted velocities (>3 km s-1 from the systemic velocities). We investigate the origin of the molecular emission in the streamer, in light of thermal sublimation temperatures calculated using updated binding energy (BE) distributions. We propose that the observed emission is produced by an accretion shock at the interface between the accretion streamer and the disk of VLA4A. Thermal desorption is not completely excluded in case the source is actively experiencing an accretion burst.

3.
Clin Invest Med ; 46(1): E4-14, 2023 03 26.
Artículo en Inglés | MEDLINE | ID: mdl-36966388

RESUMEN

PURPOSE: Women have traditionally been underrepresented in MD and MD-PhD training programs. Here, we describe the changing demographics of an MD-PhD Program over three distinct time intervals. METHODS: We designed a 64-question survey and sent it to 47 graduates of the McGill University MD-PhD program in Montréal, Québec, Canada, since its inception in 1985. We also sent a 23-question survey to the 24 students of the program in 2021. The surveys included questions related to demographics, physician-scientist training, research metrics, as well as academic and personal considerations. RESULTS: We collected responses from August 2020 to August 2021 and grouped them into three intervals based on respondent graduation year: 1995-2005 (n = 17), 2006-2020 (n = 23) and current students (n = 24). Total response rate was 90.1% (n = 64/71). We found that there are more women currently in the program compared to the 1995-2005 cohort (41.7% increase, p<0.01). In addition, women self-reported as physician-scientists less frequently than men and reported less protected research time. CONCLUSIONS: Overall, recent MD-PhD alumni represent a more diverse population compared with their earlier counterparts. Identifying barriers to training remains an important step in ensuring MD-PhD trainees become successful physician-scientists.


Asunto(s)
Investigación Biomédica , Internado y Residencia , Masculino , Humanos , Femenino , Educación de Postgrado en Medicina , Investigación Biomédica/educación , Canadá , Selección de Profesión
6.
J Phys Chem Lett ; 15(30): 7799-7805, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39051824

RESUMEN

Aiming to constrain the surface formation of HCN and HNC in the dense interstellar medium on ice-covered dust grains, we investigate the interaction of CN radicals with H2O and CO ices and their subsequent reactivity with H and H2. CN radicals can physisorb on both ices. However, on H2O ice, a hemibond formation is the most common binding mode, while on CO ice, the CN-CO van der Waals complex can form NCCO with a small energy barrier. We show low barrier or barrierless pathways to the formation of HCN and HNC for the reaction H + CN on both ices. Reactivity with H2 involves activation energy barriers to form HCN, which may be overcome by quantum tunneling, while HNC formation is unlikely. The formation of HCN and HNC competes with the formation of NH2CHO on H2O and HCOCN on CO.

7.
NPJ Precis Oncol ; 7(1): 73, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37558751

RESUMEN

Immune checkpoint inhibitors (ICI) are highly effective in specific cancers where canonical markers of antitumor immunity are used for patient selection. Improved predictors of T cell-inflammation are needed to identify ICI-responsive tumor subsets in additional cancer types. We investigated associations of a 4-chemokine expression signature (c-Score: CCL4, CCL5, CXCL9, CXCL10) with metrics of antitumor immunity across tumor types. Across cancer entities from The Cancer Genome Atlas, subgroups of tumors displayed high expression of the c-Score (c-Scorehi) with increased expression of immune checkpoint (IC) genes and transcriptional hallmarks of the cancer-immunity cycle. There was an incomplete association of the c-Score with high tumor mutation burden (TMB), with only 15% of c-Scorehi tumors displaying ≥10 mutations per megabase. In a heterogeneous pan-cancer cohort of 82 patients, with advanced and previously treated solid cancers, c-Scorehi tumors had a longer median time to progression (103 versus 72 days, P = 0.012) and overall survival (382 versus 196 days, P = 0.038) following ICI therapy initiation, compared to patients with low c-Score expression. We also found c-Score stratification to outperform TMB assignment for overall survival prediction (HR = 0.42 [0.22-0.79], P = 0.008 versus HR = 0.60 [0.29-1.27], P = 0.18, respectively). Assessment of the c-Score using the TIDE and PredictIO databases, which include ICI treatment outcomes from 10 tumor types, provided further support for the c-Score as a predictive ICI therapeutic biomarker. In summary, the c-Score identifies patients with hallmarks of T cell-inflammation and potential response to ICI treatment across cancer types, which is missed by TMB assignment.

8.
Polymers (Basel) ; 14(16)2022 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-36015669

RESUMEN

The automotive industry has used plastics almost since the beginning. The lightness, flexibility, and many qualities of plastics make them ideal for the automotive industry, reducing cars' overall weight and fuel consumption. Engineering plastics in this industry belong to the high-performance segment of non-renewable resources. These plastics exhibit higher properties than commodity plastics. Fortunately, unlike recycled commodity plastics, the super properties and high-performance characteristics make engineering plastics effectively reused after recycling. The substitution of these fossil-fuel-derived plastics adds to the solution of lightweighting, a much-needed solution to waste management, and solves industrial and ecological issues surrounding plastic disposal. All major vehicle manufacturers worldwide use bioplastics and bio-based plastics, including natural-fiber composites and engineering plastics reinforced with natural fibers. Changing the source of plastics to raw materials from renewable resources is the logical approach to sustainability. Thus, high-quality plastics, recycled plastics, bio-based plastics, and biodegradable plastics could be exploited from design, making sustainability an integral concept of mobility development. This review analyzes that switching from fossil-fuel- to renewable-sources-derived plastics is a step toward meeting the current environmental goals for the automotive industry, including electric cars.

9.
ACS Earth Space Chem ; 6(3): 496-511, 2022 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-35330630

RESUMEN

Ethanol (CH3CH2OH) is a relatively common molecule, often found in star-forming regions. Recent studies suggest that it could be a parent molecule of several so-called interstellar complex organic molecules (iCOMs). However, the formation route of this species remains under debate. In the present work, we study the formation of ethanol through the reaction of CCH with one H2O molecule belonging to the ice as a test case to investigate the viability of chemical reactions based on a "radical + ice component" scheme as an alternative mechanism for the synthesis of iCOMs, beyond the usual radical-radical coupling. This has been done by means of DFT calculations adopting two clusters of 18 and 33 water molecules as ice models. Results indicate that CH3CH2OH can potentially be formed by this proposed reaction mechanism. The reaction of CCH with H2O on the water ice clusters can be barrierless (because of the help of boundary icy water molecules acting as proton-transfer assistants), leading to the formation of vinyl alcohol precursors (H2CCOH and CHCHOH). Subsequent hydrogenation of vinyl alcohol yielding ethanol is the only step presenting a low activation energy barrier. We finally discuss the astrophysical implications of these findings.

10.
Front Oncol ; 12: 860767, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35547873

RESUMEN

The immune contexture of pancreatic ductal adenocarcinoma (PDAC) is generally immunosuppressive. A role for immune checkpoint inhibitors (ICIs) in PDAC has only been demonstrated for the rare and hypermutated mismatch repair (MMR) deficient (MMR-d) subtype. Homologous recombination repair (HR) deficient (HR-d) PDAC is more prevalent and may encompass up to 20% of PDAC. Its genomic instability may promote a T-cell mediated anti-tumor response with therapeutic sensitivity to ICIs. To investigate the immunogenicity of HR-d PDAC, we used multiplex immunohistochemistry (IHC) to compare the density and spatial distribution of CD8+ cytotoxic T-cells, FOXP3+ regulatory T-cells (Tregs), and CD68+ tumor-associated macrophages (TAMs) in HR-d versus HR/MMR-intact PDAC. We also evaluated the IHC positivity of programmed death-ligand 1 (PD-L1) across the subgroups. 192 tumors were evaluated and classified as HR/MMR-intact (n=166), HR-d (n=25) or MMR-d (n=1) based on germline testing and tumor molecular hallmarks. Intra-tumoral CD8+ T-cell infiltration was higher in HR-d versus HR/MMR-intact PDAC (p<0.0001), while CD8+ T-cell densities in the peri-tumoral and stromal regions were similar in both groups. HR-d PDAC also displayed increased intra-tumoral FOXP3+ Tregs (p=0.049) and had a higher CD8+:FOXP3+ ratio (p=0.023). CD68+ TAM expression was similar in HR-d and HR/MMR-intact PDAC. Finally, 6 of the 25 HR-d cases showed a PD-L1 Combined Positive Score of >=1, whereas none of the HR/MMR-intact cases met this threshold (p<0.00001). These results provide immunohistochemical evidence for intra-tumoral CD8+ T-cell enrichment and PD-L1 positivity in HR-d PDAC, suggesting that HR-d PDAC may be amenable to ICI treatment strategies.

11.
Nurse Lead ; 19(2): 170-178, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32922217

RESUMEN

A multispecialty nursing team plays a crucial role in key decision making, education, prevention, screening, assessment, diagnosis, management, data collection and dissemination of best practices during the novel coronavirus disease (COVID-19) pandemic. Using examples from a large, tertiary medical center in Los Angeles, this paper highlights contributions made by multispecialty nursing specialties to optimize health and safety for patients and frontline health care workers. Recognizing nurses' ongoing critical role encourages and informs further collaboration and serves as a catalyst to innovation for a healthier tomorrow. The result of the COVID-19 pandemic will be felt for years to come.

12.
Clin Cancer Res ; 26(8): 1997-2010, 2020 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-31964786

RESUMEN

PURPOSE: The molecular drivers of antitumor immunity in pancreatic ductal adenocarcinoma (PDAC) are poorly understood, posing a major obstacle for the identification of patients potentially amenable for immune-checkpoint blockade or other novel strategies. Here, we explore the association of chemokine expression with effector T-cell infiltration in PDAC. EXPERIMENTAL DESIGN: Discovery cohorts comprised 113 primary resected PDAC and 107 PDAC liver metastases. Validation cohorts comprised 182 PDAC from The Cancer Genome Atlas and 92 PDACs from the Australian International Cancer Genome Consortium. We explored associations between immune cell counts by immunohistochemistry, chemokine expression, and transcriptional hallmarks of antitumor immunity by RNA sequencing (RNA-seq), and mutational burden by whole-genome sequencing. RESULTS: Among all known human chemokines, a coregulated set of four (CCL4, CCL5, CXCL9, and CXCL10) was strongly associated with CD8+ T-cell infiltration (P < 0.001). Expression of this "4-chemokine signature" positively correlated with transcriptional metrics of T-cell activation (ZAP70, ITK, and IL2RB), cytolytic activity (GZMA and PRF1), and immunosuppression (PDL1, PD1, CTLA4, TIM3, TIGIT, LAG3, FASLG, and IDO1). Furthermore, the 4-chemokine signature marked tumors with increased T-cell activation scores (MHC I presentation, T-cell/APC costimulation) and elevated expression of innate immune sensing pathways involved in T-cell priming (STING and NLRP3 inflammasome pathways, BATF3-driven dendritic cells). Importantly, expression of this 4-chemokine signature was consistently indicative of a T-cell-inflamed phenotype across primary PDAC and PDAC liver metastases. CONCLUSIONS: A conserved 4-chemokine signature marks resectable and metastatic PDAC tumors with an active antitumor phenotype. This could have implications for the appropriate selection of PDAC patients in immunotherapy trials.


Asunto(s)
Biomarcadores de Tumor/genética , Linfocitos T CD8-positivos/inmunología , Quimiocina CCL4/genética , Quimiocina CCL5/genética , Quimiocina CXCL10/genética , Quimiocina CXCL9/genética , Neoplasias Hepáticas/secundario , Neoplasias Pancreáticas/patología , Biomarcadores de Tumor/inmunología , Quimiocina CCL4/inmunología , Quimiocina CCL5/inmunología , Quimiocina CXCL10/inmunología , Quimiocina CXCL9/inmunología , Estudios de Cohortes , Biología Computacional/métodos , Bases de Datos Genéticas/estadística & datos numéricos , Humanos , Proteínas de Punto de Control Inmunitario/genética , Inmunoterapia/métodos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Mutación , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/inmunología , RNA-Seq/métodos
13.
Cancer Cell ; 35(2): 267-282.e7, 2019 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-30686769

RESUMEN

We integrated clinical, genomic, and transcriptomic data from 224 primaries and 95 metastases from 289 patients to characterize progression of pancreatic ductal adenocarcinoma (PDAC). Driver gene alterations and mutational and expression-based signatures were preserved, with truncations, inversions, and translocations most conserved. Cell cycle progression (CCP) increased with sequential inactivation of tumor suppressors, yet remained higher in metastases, perhaps driven by cell cycle regulatory gene variants. Half of the cases were hypoxic by expression markers, overlapping with molecular subtypes. Paired tumor heterogeneity showed cancer cell migration by Halstedian progression. Multiple PDACs arising synchronously and metachronously in the same pancreas were actually intra-parenchymal metastases, not independent primary tumors. Established clinical co-variates dominated survival analyses, although CCP and hypoxia may inform clinical practice.


Asunto(s)
Biomarcadores de Tumor/genética , Carcinoma Ductal Pancreático/genética , Ciclo Celular/genética , Movimiento Celular/genética , Proliferación Celular/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias Hepáticas/genética , Mutación , Neoplasias Pancreáticas/genética , Transcripción Genética , Animales , Biomarcadores de Tumor/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/secundario , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Predisposición Genética a la Enfermedad , Humanos , Israel , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/secundario , Ratones , Invasividad Neoplásica , América del Norte , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patología , Fenotipo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma , Hipoxia Tumoral
14.
Oncotarget ; 9(27): 19159-19176, 2018 Apr 10.
Artículo en Inglés | MEDLINE | ID: mdl-29721191

RESUMEN

MicroRNAs (miRNAs) are small noncoding RNA molecules that post-transcriptionally regulate gene expression. Dysregulation of miRNAs is frequently associated with disease and, in particular, is involved in prostate cancer progression. Next generation miRNA sequencing identified a panel of five miRNAs associated with prostate cancer recurrence and metastasis. High expression of one of these five miRNAs, miR-652, correlated significantly with an increased rate of prostate cancer biochemical recurrence. Overexpression of miR-652 in prostate cancer cells, PC3 and LNCaP, resulted in increased growth, migration and invasion. Prostate cancer cell xenografts overexpressing miR-652 showed increased tumorigenicity and metastases. We found that miR-652 directly targets the B" regulatory subunit, PPP2R3A, of the tumor suppressor PP2A, inducing epithelial-mesenchymal transition (EMT) in PC3 cells and neuroendocrine-like differentiation (NED) in LNCaP cells. The mesenchymal marker N-cadherin increased and epithelial marker E-cadherin decreased in PC3 cells overexpressing miR-652. In LNCaP cells and xenografted tumors, overexpression of miR-652 increased markers of NED, including chromogranin A, neuron specific enolase, and synaptophysin. MiR-652 may contribute to prostate tumor progression by promoting NED through decreased PP2A function. MiR-652 expression could serve as a biomarker for aggressive prostate cancer, as well as provide an opportunity for novel therapy in prostate cancer.

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