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1.
Cell ; 176(6): 1295-1309.e15, 2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-30773314

RESUMEN

Cancers from sun-exposed skin accumulate "driver" mutations, causally implicated in oncogenesis. Because errors incorporated during translesion synthesis (TLS) opposite UV lesions would generate these mutations, TLS mechanisms are presumed to underlie cancer development. To address the role of TLS in skin cancer formation, we determined which DNA polymerase is responsible for generating UV mutations, analyzed the relative contributions of error-free TLS by Polη and error-prone TLS by Polθ to the replication of UV-damaged DNA and to genome stability, and examined the incidence of UV-induced skin cancers in Polθ-/-, Polη-/-, and Polθ-/- Polη-/- mice. Our findings that the incidence of skin cancers rises in Polθ-/- mice and is further exacerbated in Polθ-/- Polη-/- mice compared with Polη-/- mice support the conclusion that error-prone TLS by Polθ provides a safeguard against tumorigenesis and suggest that cancer formation can ensue in the absence of somatic point mutations.


Asunto(s)
ADN Polimerasa Dirigida por ADN/metabolismo , ADN Polimerasa Dirigida por ADN/fisiología , Neoplasias Cutáneas/metabolismo , Animales , Daño del ADN/genética , Reparación del ADN/genética , Replicación del ADN/fisiología , Fibroblastos/metabolismo , Fibroblastos/efectos de la radiación , Inestabilidad Genómica/genética , Humanos , Ratones , Ratones Noqueados , Mutación/genética , Piel/citología , Piel/metabolismo , Neoplasias Cutáneas/genética , Rayos Ultravioleta/efectos adversos , ADN Polimerasa theta
2.
Genes Dev ; 31(18): 1847-1857, 2017 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-29021240

RESUMEN

TP53 is the most frequently mutated gene in human cancer. Many mutant p53 proteins exert oncogenic gain-of-function (GOF) properties that contribute to metastasis, but the mechanisms mediating these functions remain poorly defined in vivo. To elucidate how mutant p53 GOF drives metastasis, we developed a traceable somatic osteosarcoma mouse model that is initiated with either a single p53 mutation (p53R172H) or p53 loss in osteoblasts. Our study confirmed that p53 mutant mice developed osteosarcomas with increased metastasis as compared with p53-null mice. Comprehensive transcriptome RNA sequencing (RNA-seq) analysis of 16 tumors identified a cluster of small nucleolar RNAs (snoRNAs) that are highly up-regulated in p53 mutant tumors. Regulatory element analysis of these deregulated snoRNA genes identified strong enrichment of a common Ets2 transcription factor-binding site. Homozygous deletion of Ets2 in p53 mutant mice resulted in strong down-regulation of snoRNAs and reversed the prometastatic phenotype of mutant p53 but had no effect on osteosarcoma development, which remained 100% penetrant. In summary, our studies identify Ets2 inhibition as a potential therapeutic vulnerability in p53 mutant osteosarcomas.


Asunto(s)
Neoplasias Óseas/genética , Neoplasias Óseas/patología , Regulación Neoplásica de la Expresión Génica , Osteosarcoma/genética , Osteosarcoma/secundario , Proteína Proto-Oncogénica c-ets-2/genética , ARN Nucleolar Pequeño/genética , Proteína p53 Supresora de Tumor/genética , Animales , Regulación hacia Abajo , Perfilación de la Expresión Génica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/secundario , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Ratones , Ratones Noqueados , Mutación , Metástasis de la Neoplasia , Análisis de Secuencia por Matrices de Oligonucleótidos , Osteoblastos/metabolismo , Osteoblastos/patología , Regulación hacia Arriba
3.
Support Care Cancer ; 29(11): 6201-6209, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-33822240

RESUMEN

PURPOSE: Literature supporting the efficacy of complementary and integrative medicine (CIM) alongside radiotherapy is fragmented with varying outcomes and levels of evidence. This review summarizes the available evidence on CIM used with radiotherapy in order to inform clinicians. METHODS: A systematic literature review identified studies on the use of CIM during radiotherapy. Inclusion required the following criteria: the study was interventional, CIM therapy was for human patients with cancer, and CIM therapy was administered concurrently with radiotherapy. Data points of interest were collected from included studies. A subset was identified as high-quality using the Jadad scale. Fisher's exact test was used to assess the association between study results, outcome measured, and type of CIM. RESULTS: Overall, 163 articles met inclusion. Of these, 68 (41.7%) were considered high-quality trials. Articles published per year increased over time (p < 0.01). Frequently identified therapies were biologically based therapies (47.9%), mind-body therapies (23.3%), and alternative medical systems (13.5%). Within the subset of high-quality trials, 60.0% of studies reported a favorable change with CIM while 40.0% reported no change. No studies reported an unfavorable change. Commonly assessed outcome types were patient-reported (41.1%) and provider-reported (21.5%). Rate of favorable change did not differ based on type of CIM (p = 0.90) or outcome measured (p = 0.24). CONCLUSIONS: Concurrent CIM may reduce radiotherapy-induced toxicities and improve quality of life, suggesting that physicians should discuss CIM with patients receiving radiotherapy. This review provides a broad overview of investigations on CIM use during radiotherapy and can inform how radiation oncologists advise their patients about CIM.


Asunto(s)
Terapias Complementarias , Medicina Integrativa , Humanos , Manejo del Dolor , Calidad de Vida , Autocuidado
4.
Pituitary ; 22(2): 105-112, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30656597

RESUMEN

PURPOSE: Oxytocin is a hypothalamus derived, posterior pituitary stored nonapeptide which has gained recent interest as an important neuropsychiatric and metabolic hormone beyond its classic role in lactation and parturition. Hypopituitarism is a heterogenous disorder of derangement in one or more anterior or posterior pituitary hormones. Diagnosis of deficiency and hormone replacement exists to address all relevant axes except for oxytocin. Our study aims to define derangements in oxytocin in a unique population of patients with hypopituitarism and correlate levels with measures of emotional health and quality of life. METHODS: A cross-sectional, single day study was completed to measure plasma oxytocin levels in a diverse population of patients with hypopituitarism compared to controls. Subjects also completed depression, quality of life and stress-related questionnaires, and emotion recognition tasks. RESULTS: Thirty-eight subjects completed the study, 18 with hypopituitarism (9 with diabetes insipidus) and 20 controls. After controlling for differences in age, weight and gender, plasma oxytocin levels were highest in subjects with diabetes insipidus compared to control [mean, IQR: 44.3 pg/ml (29.8-78.2) vs. 20.6 (17-31.3), p = 0.032]. Amongst hypopituitary subjects, those with duration of disease greater than 1 year had higher oxytocin levels. No significant differences were observed for psychosocial measures including emotion recognition tasks. CONCLUSIONS: Plasma oxytocin levels were found higher in patients with hypopituitarism compared to controls and highest in those with diabetes insipidus. Longer duration of hypopituitarism was also associated with higher plasma levels of oxytocin. Further study is needed to better define oxytocin deficiency and investigate response to treatment.


Asunto(s)
Hipopituitarismo/sangre , Hipopituitarismo/fisiopatología , Oxitocina/sangre , Adulto , Anciano , Estudios Transversales , Diabetes Insípida/sangre , Diabetes Insípida/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Encuestas y Cuestionarios
5.
Radiology ; 286(1): 149-157, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28825892

RESUMEN

Purpose To assess for nanopore formation in bone marrow cells after irreversible electroporation (IRE) and to evaluate the antitumoral effect of IRE, used alone or in combination with doxorubicin (DOX)-loaded superparamagnetic iron oxide (SPIO) nanoparticles (SPIO-DOX), in a VX2 rabbit tibial tumor model. Materials and Methods All experiments were approved by the institutional animal care and use committee. Five porcine vertebral bodies in one pig underwent intervention (IRE electrode placement without ablation [n = 1], nanoparticle injection only [n = 1], and nanoparticle injection followed by IRE [n = 3]). The animal was euthanized and the vertebrae were harvested and evaluated with scanning electron microscopy. Twelve rabbit VX2 tibial tumors were treated, three with IRE, three with SPIO-DOX, and six with SPIO-DOX plus IRE; five rabbit VX2 tibial tumors were untreated (control group). Dynamic T2*-weighted 4.7-T magnetic resonance (MR) images were obtained 9 days after inoculation and 2 hours and 5 days after treatment. Antitumor effect was expressed as the tumor growth ratio at T2*-weighted MR imaging and percentage necrosis at histologic examination. Mixed-effects linear models were used to analyze the data. Results Scanning electron microscopy demonstrated nanopores in bone marrow cells only after IRE (P , .01). Average volume of total tumor before treatment (503.1 mm3 ± 204.6) was not significantly different from those after treatment (P = .7). SPIO-DOX was identified as a reduction in signal intensity within the tumor on T2*-weighted images for up to 5 days after treatment and was related to the presence of iron. Average tumor growth ratios were 103.0% ± 75.8 with control treatment, 154.3% ± 79.7 with SPIO-DOX, 77% ± 30.8 with IRE, and -38.5% ± 24.8 with a combination of SPIO-DOX and IRE (P = .02). The percentage residual viable tumor in bone was significantly less for combination therapy compared with control (P = .02), SPIO-DOX (P , .001), and IRE (P = .03) treatment. The percentage residual viable tumor in soft tissue was significantly less with IRE (P = .005) and SPIO-DOX plus IRE (P = .005) than with SPIO-DOX. Conclusion IRE can induce nanopore formation in bone marrow cells. Tibial VX2 tumors treated with a combination of SPIO-DOX and IRE demonstrate enhanced antitumor effect as compared with individual treatments alone. © RSNA, 2017 Online supplemental material is available for this article.


Asunto(s)
Células de la Médula Ósea/efectos de los fármacos , Neoplasias Óseas/diagnóstico , Neoplasias Óseas/secundario , Electroporación/métodos , Nanopartículas de Magnetita/química , Modelos Biológicos , Nanoporos , Animales , Antibióticos Antineoplásicos/farmacología , Doxorrubicina/farmacología , Conejos , Porcinos , Tibia/citología
6.
Radiology ; 285(3): 820-829, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28708470

RESUMEN

Purpose To evaluate the immediate and long-term safety as well as thrombus-capturing efficacy for 5 weeks after implantation of an absorbable inferior vena cava (IVC) filter in a swine model. Materials and Methods This study was approved by the institutional animal care and use committee. Eleven absorbable IVC filters made from polydioxanone suture were deployed via a catheter in the IVC of 11 swine. Filters remained in situ for 2 weeks (n = 2), 5 weeks (n = 2), 12 weeks (n = 2), 24 weeks (n = 2), and 32 weeks (n = 3). Autologous thrombus was administered from below the filter in seven swine from 0 to 35 days after filter placement. Fluoroscopy and computed tomography follow-up was performed after filter deployment from weeks 1-6 (weekly), weeks 7-20 (biweekly), and weeks 21-32 (monthly). The infrarenal IVC, lungs, heart, liver, kidneys, and spleen were harvested at necropsy. Continuous variables were evaluated with a Student t test. Results There was no evidence of IVC thrombosis, device migration, caval penetration, or pulmonary embolism. Gross pathologic analysis showed gradual device resorption until 32 weeks after deployment. Histologic assessment demonstrated neointimal hyperplasia around the IVC filter within 2 weeks after IVC filter deployment with residual microscopic fragments of polydioxanone suture within the caval wall at 32 weeks. Each iatrogenic-administered thrombus was successfully captured by the filter until resorbed (range, 1-4 weeks). Conclusion An absorbable IVC filter can be safely deployed in swine and resorbs gradually over the 32-week testing period. The device is effective for the prevention of pulmonary embolism for at least 5 weeks after placement in swine. © RSNA, 2017.


Asunto(s)
Implantes Absorbibles , Hemofiltración/instrumentación , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/prevención & control , Filtros de Vena Cava , Vena Cava Inferior/diagnóstico por imagen , Animales , Angiografía por Tomografía Computarizada , Diseño de Equipo , Análisis de Falla de Equipo , Hemofiltración/métodos , Embolia Pulmonar/patología , Porcinos , Porcinos Enanos , Resultado del Tratamiento
7.
Proc Natl Acad Sci U S A ; 110 Suppl 2: 10395-401, 2013 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-23754422

RESUMEN

Neocortical development in humans is characterized by an extended period of synaptic proliferation that peaks in mid-childhood, with subsequent pruning through early adulthood, as well as relatively delayed maturation of neuronal arborization in the prefrontal cortex compared with sensorimotor areas. In macaque monkeys, cortical synaptogenesis peaks during early infancy and developmental changes in synapse density and dendritic spines occur synchronously across cortical regions. Thus, relatively prolonged synapse and neuronal maturation in humans might contribute to enhancement of social learning during development and transmission of cultural practices, including language. However, because macaques, which share a last common ancestor with humans ≈ 25 million years ago, have served as the predominant comparative primate model in neurodevelopmental research, the paucity of data from more closely related great apes leaves unresolved when these evolutionary changes in the timing of cortical development became established in the human lineage. To address this question, we used immunohistochemistry, electron microscopy, and Golgi staining to characterize synaptic density and dendritic morphology of pyramidal neurons in primary somatosensory (area 3b), primary motor (area 4), prestriate visual (area 18), and prefrontal (area 10) cortices of developing chimpanzees (Pan troglodytes). We found that synaptogenesis occurs synchronously across cortical areas, with a peak of synapse density during the juvenile period (3-5 y). Moreover, similar to findings in humans, dendrites of prefrontal pyramidal neurons developed later than sensorimotor areas. These results suggest that evolutionary changes to neocortical development promoting greater neuronal plasticity early in postnatal life preceded the divergence of the human and chimpanzee lineages.


Asunto(s)
Dendritas , Neocórtex , Pan troglodytes , Filogenia , Células Piramidales , Sinapsis/fisiología , Animales , Dendritas/fisiología , Retroalimentación Sensorial/fisiología , Femenino , Humanos , Masculino , Neocórtex/citología , Neocórtex/fisiología , Pan troglodytes/anatomía & histología , Pan troglodytes/fisiología , Células Piramidales/citología , Células Piramidales/fisiología
8.
Antimicrob Agents Chemother ; 59(9): 5611-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26124171

RESUMEN

Antimicrobial peripherally inserted central catheters (PICCs) might reduce the incidence of central line-associated bloodstream infections (CLABSI). We tested the biocompatibility of a novel gendine-coated (combination of chlorhexidine [CHX] and gentian violet [GV]) PICC in a rabbit intravascular model and tested antimicrobial efficacy in comparison with commercially available minocycline/rifampin (M/R)- and CHX-treated PICCs in an in vitro biofilm colonization model. Gendine-coated and uncoated control PICCs were inserted in the jugular veins of rabbits for 4 days. Histopathological analysis was performed at the end of the 4-day period, and circulating levels of CHX and GV in the blood were measured at different time points using liquid chromatography-mass spectrometry. The antimicrobial efficacy of the PICCs was tested following simulated intravascular indwells of 24 h and 1 week against clinical isolates of methicillin-resistant Staphylococcus aureus, vancomycin-resistant enterococci, Pseudomonas aeruginosa, Escherichia coli, Acinetobacter baumannii, Enterobacter cloacae, Candida albicans, and Candida glabrata. Rabbits implanted with gendine-coated PICCs exhibited reduced levels of thrombosis and inflammation compared to those of the rabbits with uncoated controls. No GV was detected in blood samples over the entire study period, and trace concentrations of CHX were detected. The gendine-coated PICCs completely prevented the adherence of all pathogens from 24 h to 1 week (P ≤ 0.001), while M/R-treated, CHX-treated, and control PICCs did not. Gendine-coated PICCs were highly effective in preventing biofilm formation of multidrug-resistant pathogenic bacteria and fungi. Gendine-coated PICCs were biocompatible in an intravascular setting. Further, the pharmacokinetic testing established that acute systemic exposures of CHX and GV from the gendine-coated catheters were well within safe levels.


Asunto(s)
Antiinfecciosos/farmacología , Catéteres de Permanencia/microbiología , Acinetobacter baumannii/efectos de los fármacos , Animales , Antiinfecciosos/efectos adversos , Biopelículas/efectos de los fármacos , Candida albicans/efectos de los fármacos , Candida glabrata/efectos de los fármacos , Enterobacter cloacae/efectos de los fármacos , Femenino , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Minociclina/efectos adversos , Minociclina/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Conejos , Rifampin/efectos adversos , Rifampin/farmacología , Enterococos Resistentes a la Vancomicina/efectos de los fármacos
9.
Proc Natl Acad Sci U S A ; 109(41): 16480-5, 2012 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-23012402

RESUMEN

Nerve myelination facilitates saltatory action potential conduction and exhibits spatiotemporal variation during development associated with the acquisition of behavioral and cognitive maturity. Although human cognitive development is unique, it is not known whether the ontogenetic progression of myelination in the human neocortex is evolutionarily exceptional. In this study, we quantified myelinated axon fiber length density and the expression of myelin-related proteins throughout postnatal life in the somatosensory (areas 3b/3a/1/2), motor (area 4), frontopolar (prefrontal area 10), and visual (areas 17/18) neocortex of chimpanzees (N = 20) and humans (N = 33). Our examination revealed that neocortical myelination is developmentally protracted in humans compared with chimpanzees. In chimpanzees, the density of myelinated axons increased steadily until adult-like levels were achieved at approximately the time of sexual maturity. In contrast, humans displayed slower myelination during childhood, characterized by a delayed period of maturation that extended beyond late adolescence. This comparative research contributes evidence crucial to understanding the evolution of human cognition and behavior, which arises from the unfolding of nervous system development within the context of an enriched cultural environment. Perturbations of normal developmental processes and the decreased expression of myelin-related molecules have been related to psychiatric disorders such as schizophrenia. Thus, these species differences suggest that the human-specific shift in the timing of cortical maturation during adolescence may have implications for vulnerability to certain psychiatric disorders.


Asunto(s)
Evolución Biológica , Proteínas de la Mielina/metabolismo , Vaina de Mielina/metabolismo , Neocórtex/metabolismo , Adolescente , Adulto , Animales , Western Blotting , Niño , Humanos , Lactante , Recién Nacido , Corteza Motora/crecimiento & desarrollo , Corteza Motora/metabolismo , Glicoproteína Asociada a Mielina/metabolismo , Neocórtex/crecimiento & desarrollo , Pan troglodytes , Corteza Prefrontal/crecimiento & desarrollo , Corteza Prefrontal/metabolismo , Corteza Somatosensorial/crecimiento & desarrollo , Corteza Somatosensorial/metabolismo , Factores de Tiempo , Corteza Visual/crecimiento & desarrollo , Corteza Visual/metabolismo , Adulto Joven
10.
Cereb Cortex ; 23(10): 2429-36, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22875862

RESUMEN

The primate cerebral cortex is characterized by regional variation in the structure of pyramidal neurons, with more complex dendritic arbors and greater spine density observed in prefrontal compared with sensory and motor cortices. Although there are several investigations in humans and other primates, virtually nothing is known about regional variation in the morphology of pyramidal neurons in the cerebral cortex of great apes, humans' closest living relatives. The current study uses the rapid Golgi stain to quantify the dendritic structure of layer III pyramidal neurons in 4 areas of the chimpanzee cerebral cortex: Primary somatosensory (area 3b), primary motor (area 4), prestriate visual (area 18), and prefrontal (area 10) cortex. Consistent with previous studies in humans and macaque monkeys, pyramidal neurons in the prefrontal cortex of chimpanzees exhibit greater dendritic complexity than those in other cortical regions, suggesting that prefrontal cortical evolution in primates is characterized by increased potential for integrative connectivity. Compared with chimpanzees, the pyramidal neurons of humans had significantly longer and more branched dendritic arbors in all cortical regions.


Asunto(s)
Dendritas/ultraestructura , Neocórtex/citología , Células Piramidales/ultraestructura , Animales , Femenino , Humanos , Masculino , Pan troglodytes
11.
Clin Imaging ; 104: 110013, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37918136

RESUMEN

Various infectious and inflammatory diseases affect the genitourinary system. This paper provides a review of multiple common and uncommon infectious and inflammatory conditions affecting the genitourinary system and some associated complications. These include acute infectious cystitis, emphysematous cystitis, acute pyelonephritis, emphysematous pyelonephritis, renal and perinephric abscesses, pyonephrosis, xanthogranulomatous pyelonephritis, epididymo-orchitis, vasitis, prostatitis, pelvic inflammatory disease, renal hydatid infection, renal tuberculosis, actinomycosis, Erdheim-Chester Disease, IgG4-Related Kidney Disease, urethritis and urethral strictures, ureteritis cystica, and genitourinary fistulas. Radiologists should be aware of these diseases' complications and management. Uncommon conditions must be considered when evaluating the genitourinary system.


Asunto(s)
Cistitis , Enfermedades Renales , Pielonefritis , Infecciones Urinarias , Masculino , Humanos , Inflamación , Sistema Urogenital , Infecciones Urinarias/diagnóstico por imagen , Cistitis/diagnóstico por imagen
12.
Vet Pathol ; 48(5): 1041-3, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21865606

RESUMEN

Collectively, these presentations introduced the audience to the roles of ES cells in generating phenotypes of transgenic animals,and they provided examples where the GEMs were used to define molecular mechanisms of disease or where ES cells were used as a therapeutic modality. Points of discussion among audience members reinforced the importance of strain-associated background lesions in animal models, technological advances in imaging functional biology, opportunities for stem cell therapies, and ubiquitination in regulation of cell proliferation. The 2012 American College of Veterinary Pathologists symposium ''Evolutionary Aspects of Animal Models'' will focus on the proper selection of a relevant animal model in biomedical research as critical to investigative success. Recent work characterizing rapid evolutionary changes and differences in physiology between species questions the validity of some comparative models. Dr. Robert Hamlin will be speaking on cardiovascular disease in ''Animals as Models of Human Cardiovascular Disease: Or the Search to Overcome Outdated Evolutionary Homeostatic Mechanisms.'' Dr. Stefan Niewiesk will discuss evolutionary factors that affect modeling the human immune system in ''Of Mice and Men: Evolutionarily, What Are the Best Rodent Models of the Human Immune System for Infectious Disease Research?'' Dr. Steven Austad will consider evolution in ''Evolutionary Aspects of Animal Models of Aging.''Finally, Dr. Elizabeth Uhl will conclude the session with ''Modeling Disease Phenotypes: How an Evolutionary Perspective Enhances the Questions.''


Asunto(s)
Animales Modificados Genéticamente/genética , Células Madre Embrionarias/trasplante , Trasplante de Células Madre/métodos , Animales , Ratones , Fenotipo
13.
Clin Imaging ; 69: 196-204, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32919206

RESUMEN

The two most common primary liver malignancies that radiologists encounter in clinical practice are hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). However, there are other less common primary hepatic malignancies that radiologists should be aware of. The correct radiographic and pathologic diagnosis of these entities have important treatment and prognostic implications. In this paper, we review a series of five cases that we have encountered in clinical practice at our institution that were initially thought to be HCC or ICC, but turned out to be a rarer primary hepatic malignancy. We will review the radiographic and pathologic characteristics of each of these rare primary hepatic malignancies as well as discuss the prognosis and treatment for each.


Asunto(s)
Neoplasias de los Conductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Conductos Biliares Intrahepáticos , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/terapia , Colangiocarcinoma/diagnóstico por imagen , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia
14.
Cancer Prev Res (Phila) ; 14(3): 313-324, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33277316

RESUMEN

We have previously demonstrated that PD-1 blockade decreased the incidence of high-grade dysplasia in a carcinogen-induced murine model of oral squamous cell carcinoma (OSCC). It remains unknown, however, whether there are additional factors involved in escape from immune surveillance that could serve as additional targets for immunoprevention. We performed this study to further characterize the immune landscape of oral premalignant lesions (OPL) and determine the impact of targeting of the PD-1, CTLA-4, CD40, or OX40 pathways on the development of OPLs and oral carcinomas in the 4-nitroquinoline 1-oxide model. The immune pathways were targeted using mAbs or, in the case of the PD-1/PD-L1 pathway, using PD-L1-knockout (PD-L1ko) mice. After intervention, tongues and cervical lymph nodes were harvested and analyzed for malignant progression and modulation of the immune milieu, respectively. Targeting of CD40 with an agonist mAb was the most effective treatment to reduce transition of OPLs to OSCC; PD-1 alone or in combination with CTLA-4 inhibition, or PD-L1ko, also reduced progression of OPLs to OSCC, albeit to a lesser extent. Distinct patterns of immune system modulation were observed for the CD40 agonists compared with blockade of the PD-1/PD-L1 axis with or without CTLA-4 blockade; CD40 agonist generated a lasting expansion of experienced/memory cytotoxic T lymphocytes and M1 macrophages, whereas PD-1/CTLA-4 blockade resulted in a pronounced depletion of regulatory T cells among other changes. These data suggest that distinct approaches may be used for targeting different steps in the development of OSCC, and that CD40 agonists merit investigation as potential immunoprevention agents in this setting. PREVENTION RELEVANCE: PD-1/PD-L1 pathway blockade, as well as activation of the CD40 pathway, were able to prevent OPL progression into invasive OSCC in a murine model. A distinct pattern of immune modulation was observed when either the CD40 or the PD-1/PD-L1 pathways were targeted.


Asunto(s)
Anticuerpos Monoclonales/farmacología , Antígeno B7-H1/antagonistas & inhibidores , Antígenos CD40/antagonistas & inhibidores , Carcinoma de Células Escamosas/tratamiento farmacológico , Inhibidores de Puntos de Control Inmunológico/farmacología , Neoplasias de la Boca/tratamiento farmacológico , Lesiones Precancerosas/tratamiento farmacológico , 4-Nitroquinolina-1-Óxido/toxicidad , Animales , Carcinógenos/toxicidad , Carcinoma de Células Escamosas/inducido químicamente , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Femenino , Inmunoterapia , Ratones , Ratones Endogámicos C57BL , Neoplasias de la Boca/inducido químicamente , Neoplasias de la Boca/metabolismo , Neoplasias de la Boca/patología , Lesiones Precancerosas/inducido químicamente , Lesiones Precancerosas/metabolismo , Lesiones Precancerosas/patología
15.
Eur J Neurosci ; 31(8): 1456-64, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20384782

RESUMEN

Although behavioral lateralization is known to correlate with certain aspects of brain asymmetry in primates, there are limited data concerning hemispheric biases in the microstructure of the neocortex. In the present study, we investigated whether there is asymmetry in synaptophysin-immunoreactive puncta density and protein expression levels in the region of hand representation of the primary motor cortex in chimpanzees (Pan troglodytes). Synaptophysin is a presynaptic vesicle-associated protein found in nearly all synapses of the central nervous system. We also tested whether there is a relationship between hand preference on a coordinated bimanual task and the interhemispheric distribution of synaptophysin as measured by both stereologic counts of immunoreactive puncta and by Western blotting. Our results demonstrated that synaptophysin-immunoreactive puncta density is not asymmetric at the population level, whereas synaptophysin protein expression levels are significantly higher in the right hemisphere. Handedness was correlated with interindividual variation in synaptophysin-immunoreactive puncta density. As a group, left-handed and ambidextrous chimpanzees showed a rightward bias in puncta density. In contrast, puncta densities were symmetrical in right-handed chimpanzees. These findings support the conclusion that synapse asymmetry is modulated by lateralization of skilled motor behavior in chimpanzees.


Asunto(s)
Lateralidad Funcional/fisiología , Corteza Motora/metabolismo , Sinaptofisina/metabolismo , Animales , Western Blotting , Femenino , Mano/fisiología , Inmunohistoquímica , Masculino , Actividad Motora/fisiología , Neocórtex/metabolismo , Pan troglodytes
16.
Mol Carcinog ; 49(2): 152-6, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19798698

RESUMEN

Deregulation of E2F transcriptional activity as a result of alterations in the p16-cyclin D-Rb pathway is a hallmark of cancer. However, the roles of the different E2F family members in the process of tumorigenesis are still being elucidated. Studies in mice and humans suggest that E2F2 functions as a tumor suppressor. Here we demonstrate that E2f2 inactivation cooperates with transgenic expression of Myc to enhance tumor development in the skin and oral cavity. In fact, hemizygosity at the E2f2 locus was sufficient to increase tumor incidence in this model. Loss of E2F2 enhanced proliferation in Myc transgenic tissue but did not affect Myc-induced apoptosis. E2F2 did not behave as a simple activator of transcription in epidermal keratinocytes but instead appeared to differentially regulate gene expression dependent on the individual target. E2f2 inactivation also altered the changes in gene expression in Myc transgenic cells by enhancing the increase of some genes, such as cyclin E, and reversing the repression of other genes. These findings demonstrate that E2F2 can function as a tumor suppressor in epithelial tissues, perhaps by limiting proliferation in response to Myc.


Asunto(s)
Proliferación Celular , Transformación Celular Neoplásica , Factor de Transcripción E2F2/fisiología , Genes myc , Animales , Western Blotting , Inmunohistoquímica , Ratones , Ratones Transgénicos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
17.
Differentiation ; 77(3): 324-34, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19272531

RESUMEN

The cell-of-origin has a great impact on the types of tumors that develop and the stem/progenitor cells have long been considered main targets of malignant transformation. The SV40 (SV40-Simian Virus 40) large T and small t antigens (T/t), have been targeted to multiple-differentiated cellular compartments in transgenic mice. In most of these studies, transgenic animals develop tumors without apparent defects in animal development. In this study, we used the bovine keratin 5 (BK5) promoter to target the T/t antigens to stem/progenitor cell-containing cytokeratin 5 (CK5) cellular compartment. A transgene construct, BK5-T/t, was made and microinjected into the male pronucleus of FVB/N mouse oocytes. After implanting approximately 1700 embryos, only 7 transgenics were obtained, including 4 embryos (E9.5, E13, E15, and E20) and 3 postnatal animals, which died at P1, P2, and P18, respectively. Immunohistological analysis revealed aberrant differentiation and prominent hyperplasia in several transgenic CK5 tissues, especially the upper digestive organs (tongue, oral mucosa, esophagus, and forestomach) and epidermis, the latter of which also showed focal dysplasia. Altogether, these results indicate that constitutive expression of the T/t antigens in CK5 cellular compartment results in abnormal epithelial differentiation and leads to embryonic/perinatal animal lethality.


Asunto(s)
Diferenciación Celular , Tracto Gastrointestinal/patología , Hiperplasia , Queratina-5/metabolismo , Regiones Promotoras Genéticas , Animales , Antígenos Transformadores de Poliomavirus/metabolismo , Apoptosis , Epidermis/metabolismo , Epidermis/patología , Células Epiteliales/citología , Células Epiteliales/metabolismo , Regulación de la Expresión Génica , Hiperplasia/metabolismo , Queratina-5/genética , Masculino , Ratones , Ratones Transgénicos , Virus 40 de los Simios/genética , Virus 40 de los Simios/metabolismo , Lengua/metabolismo , Lengua/patología
18.
BMC Cancer ; 8: 268, 2008 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-18808719

RESUMEN

BACKGROUND: Overexpression of the bZip transcription factor, ATF3, in basal epithelial cells of transgenic mice under the control of the bovine cytokeratin-5 (CK5) promoter has previously been shown to induce epidermal hyperplasia, hair follicle anomalies and neoplastic lesions of the oral mucosa including squamous cell carcinomas. CK5 is known to be expressed in myoepithelial cells of the mammary gland, suggesting the possibility that transgenic BK5.ATF3 mice may exhibit mammary gland phenotypes. METHODS: Mammary glands from nulliparous mice in our BK5.ATF3 colony, both non-transgenic and transgenic, were examined for anomalies by histopathology and immunohistochemistry. Nulliparous and biparous female mice were observed for possible mammary tumor development, and suspicious masses were analyzed by histopathology and immunohistochemistry. Human breast tumor samples, as well as normal breast tissue, were similarly analyzed for ATF3 expression. RESULTS: Transgenic BK5.ATF3 mice expressed nuclear ATF3 in the basal layer of the mammary ductal epithelium, and often developed squamous metaplastic lesions in one or more mammary glands by 25 weeks of age. No progression to malignancy was seen in nulliparous BK5.ATF3 or non-transgenic mice held for 16 months. However, biparous BK5.ATF3 mice developed mammary carcinomas with squamous metaplasia between 6 months and one year of age, reaching an incidence of 67%. Cytokeratin expression in the tumors was profoundly disturbed, including expression of CK5 and CK8 (characteristic of basal and luminal cells, respectively) throughout the epithelial component of the tumors, CK6 (potentially a stem cell marker), CK10 (a marker of interfollicular epidermal differentiation), and mIRSa2 and mIRSa3.1 (markers of the inner root sheath of hair follicles). Immunohistochemical studies indicated that a subset of human breast tumors exhibit high levels of nuclear ATF3 expression. CONCLUSION: Overexpression of ATF3 in CK5-expressing cells of the murine mammary gland results in the development of squamous metaplastic lesions in nulliparous females, and in mammary tumors in biparous mice, suggesting that ATF3 acts as a mammary oncogene. A subset of human breast tumors expresses high levels of ATF3, suggesting that ATF3 may play an oncogenic role in human breast tumorigenesis, and therefore may be useful as either a biomarker or therapeutic target.


Asunto(s)
Factor de Transcripción Activador 3/fisiología , Transformación Celular Neoplásica/genética , Glándulas Mamarias Animales/patología , Oncogenes , Factor de Transcripción Activador 3/genética , Factor de Transcripción Activador 3/metabolismo , Animales , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/fisiología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Bovinos , Proliferación Celular , Femenino , Regulación Neoplásica de la Expresión Génica , Queratina-5/genética , Glándulas Mamarias Animales/crecimiento & desarrollo , Glándulas Mamarias Animales/metabolismo , Neoplasias Mamarias Animales/genética , Neoplasias Mamarias Animales/patología , Ratones , Ratones Transgénicos , Oncogenes/fisiología , Embarazo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Factores de Transcripción/fisiología , Transgenes
19.
Artículo en Inglés | MEDLINE | ID: mdl-31406393

RESUMEN

Radiopaque resorbable inferior vena cava filter (IVCF) were developed to offer a less expensive alternative to assessing filter integrity in preventing pulmonary embolism for the recommended prophylactic period and then simply vanishes without intervention. In this study, we determined the efficacy of gold nanoparticle (AuNP)-infused poly-p-dioxanone (PPDO) as an IVCF in a swine model. Infusion into PPDO loaded 1.14±0.08 % AuNP by weight as determined by elemental analysis. The infusion did not alter PPDO's mechanical strength nor crystallinity (Kruskal-Wallis one-way ANOVA, p<0.05). There was no cytotoxicity observed (one-way ANOVA, p<0.05) when tested against RF24 and MRC5 cells. Gold content in PPDO was maintained at ~2000 ppm during the 6-week incubation in PBS at 37°C. As a proof-of-concept, two pigs were deployed with IVCF, one with AuNP-PPDO and the other without coating. Results show that the stent ring of AuNP-PPDO was highly visible even in the presence of iodine-based contrast agent and after clot introduction, but not of the uncoated IVCF. Autopsy at two weeks post-implantation showed AuNP-PPDO filter was endothelialized onto the IVC wall, and no sign of filter migration was observed. The induced clot was also still trapped within the AuNP-PPDO IVCF. As a conclusion, we successfully fabricated AuNP-infused PPDO IVCF that is radiopaque, has robust mechanical strength, biocompatible, and can be imaged effectively in vivo. This suggests the efficacy of this novel, radiopaque, absorbable IVCF for monitoring its position and integrity over time, thus increasing the safety and efficacy of deep vein thrombosis treatment.

20.
J Bronchology Interv Pulmonol ; 25(4): 322-329, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29771774

RESUMEN

BACKGROUND: Population aging and lung cancer screening strategies may lead to an increase in detection of early-stage lung cancer in medical inoperable patients. Recent advances in peripheral bronchoscopy have made it a suitable platform for ablation of small peripheral tumors. METHODS: We investigated the tissue-ablative effect of a diode laser bronchoscopically applied by a laser delivery fiber (LDF) with wide aperture on porcine lung parenchyma. Laser was tested ex vivo and in vivo to identify the most effective power settings and LDF. Chest computed tomography (CT) were obtained immediately after ablation and after 3 days of observation. At day 3, necropsy was performed. RESULTS: On the basis of our ex vivo and in vivo experiments, we selected the round-tip LDF to be activated at 25 W for 20 seconds. Ten ablations were performed in 5 pigs. One ablation resulted in a pneumothorax requiring aspiration. All animals remained stable for 72 hours. CT findings at days 1 and 3 showed an area of cavitation surrounded by consolidation and ground glass. Median size of CT findings (long axis) was 26 mm (range, 24 to 38) at day 1, and 34 mm (range, 30 to 44) at day 3. Necropsy showed an area of central char measuring from 0.8×0.7×0.9 cm to 2.4×3.5×1.2 cm, surrounded by a gray-brown to dark red area. On histology, variable degrees of necrosis were evident around the charred areas. CONCLUSION: Bronchoscopic laser interstitial thermal therapy can achieve relatively large areas of ablation of normal lung parenchyma with a low rate of periprocedural complications.


Asunto(s)
Autopsia/veterinaria , Broncoscopía/instrumentación , Terapia por Láser/métodos , Neoplasias Pulmonares/cirugía , Pulmón/patología , Tejido Parenquimatoso/cirugía , Animales , Broncoscopía/métodos , Detección Precoz del Cáncer/métodos , Femenino , Marcadores Fiduciales/normas , Fluoroscopía/métodos , Terapia por Láser/efectos adversos , Terapia por Láser/estadística & datos numéricos , Pulmón/anatomía & histología , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/patología , Masculino , Necrosis/patología , Tejido Parenquimatoso/diagnóstico por imagen , Tejido Parenquimatoso/patología , Porcinos , Tomografía Computarizada por Rayos X/métodos
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