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.
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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 thetaRESUMEN
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.
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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 ArribaRESUMEN
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.
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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 TratamientoRESUMEN
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.
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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/fisiologíaRESUMEN
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.
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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 fármacosRESUMEN
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.
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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 JovenRESUMEN
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.
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Dendritas/ultraestructura , Neocórtex/citología , Células Piramidales/ultraestructura , Animales , Femenino , Humanos , Masculino , Pan troglodytesRESUMEN
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.
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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/patologíaRESUMEN
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.
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Lateralidad Funcional/fisiología , Corteza Motora/metabolismo , Sinaptofisina/metabolismo , Animales , Western Blotting , Femenino , Mano/fisiología , Inmunohistoquímica , Masculino , Actividad Motora/fisiología , Neocórtex/metabolismo , Pan troglodytesRESUMEN
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.
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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 InversaRESUMEN
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.
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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 , TransgenesRESUMEN
Colorectal cancer accounts for a substantial number of deaths each year worldwide. Lynch Syndrome is a genetic form of colorectal cancer (CRC) caused by inherited mutations in DNA mismatch repair (MMR) genes. Although researchers have developed mouse models of Lynch Syndrome through targeted mutagenesis of MMR genes, the tumors that result differ in important ways from those in Lynch Syndrome patients. We identified 60 cases of CRC in rhesus macaques (Macaca mulatta) at our facility since 2001. The tumors occur at the ileocecal junction, cecum and proximal colon and display clinicopathologic features similar to human Lynch Syndrome. We conducted immunohistochemical analysis of CRC tumors from several rhesus macaques, finding they frequently lack expression of MLH1 and PMS2 proteins, both critical MMR proteins involved in Lynch Syndrome. We also found that most macaque cases we tested exhibit microsatellite instability, a defining feature of Lynch Syndrome. Whole genome sequencing of rhesus macaque CRC cases identified mutations in MLH1 and/or MSH6 that are predicted to disrupt protein function. We conclude that this population of rhesus macaques constitutes a spontaneous model of Lynch Syndrome, matching the human disease in several significant characteristics, including genetic risk factors that parallel human Lynch Syndrome.
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To address the need for efficient and biocompatible delivery systems for systemic siRNA delivery, we developed 1,2-Dioleoyl-sn-Glycero-3-Phosphatidylcholine (DOPC) nanoliposomal EphA2-targeted therapeutic (EPHARNA). Here, we performed safety studies of EPHARNA in murine and primate models. Single dosing of EPHARNA was tested at 5 concentrations in mice (N = 15 per group) and groups were sacrificed on days 1, 14, and 28 for evaluation of clinical pathology and organ toxicity. Multiple dosing of EPHARNA was tested in mice and Rhesus macaques twice weekly at two dose levels in each model. Possible effects on hematologic parameters, serum chemistry, coagulation, and organ toxicity were assessed. Following single-dose EPHARNA administration to mice, no gross pathologic or dose-related microscopic findings were observed in either the acute (24 hours) or recovery (14 and 28 days) phases. The no-observed-adverse-effect level (NOAEL) for EPHARNA is considered >225 µg/kg when administered as a single injection intravenously in CD-1 mice. With twice weekly injection, EPHARNA appeared to stimulate a mild to moderate inflammatory response in a dose-related fashion. There appeared to be a mild hemolytic reaction in the female mice. In Rhesus macaques, minimal to moderate infiltration of mononuclear cells was found in some organs including the gastrointestinal tract, heart, and kidney. No differences attributed to EPHARNA were observed. These results demonstrate that EPHARNA is well tolerated at all doses tested. These data, combined with previously published in vivo validation studies, have led to an ongoing first-in-human phase I clinical trial (NCT01591356). Mol Cancer Ther; 16(6); 1114-23. ©2017 AACR.
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Liposomas , Nanopartículas , Fosfatidilcolinas , Interferencia de ARN , ARN Interferente Pequeño/genética , Receptor EphA2/genética , Animales , Biomarcadores , Evaluación Preclínica de Medicamentos , Femenino , Humanos , Macaca mulatta , Masculino , Ratones , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/efectos adversos , ARN Interferente Pequeño/farmacocinética , Distribución TisularRESUMEN
Among 585 sentinel ICR mice (Mus musculus), 8 (7 female, 1 male) had unusual microscopic lesions in the kidney. Light microscopy revealed occasional tubular epithelial cells with large, karyomegalic nuclei that contained intranuclear inclusions and marginated chromatin. These cells were randomly present in the cortex and medulla but were more prominent near the corticomedullary junc tion. Rare pyknotic cells and mild interstitial infiltrates of lymphocytes and plasma cells were associated with occasional foci of abnormal cells. Electron microscopy performed on 2 (1 female, 1 male) of the mice demonstrated intranuclear inclusions composed of abundant flocculent, electron-lucent material. No viral particles or other pathogens were identified. General health monitoring that included serology, microbiology, parasitology, necropsy, and histopathology was negative for pathogens. Polymerase chain reaction-based testing for polyomavirus and immunohistochemistry for adenovirus were performed on 5 of the 7 female mice; all were negative for both viruses. In light of microscopy findings and the lack of evidence for an infectious agent, the tubular lesions were considered degenerative changes, possibly due to a toxic insult. The cause and significance of the findings in these mice can not be explained fully.
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Núcleo Celular/ultraestructura , Cuerpos de Inclusión Intranucleares/ultraestructura , Enfermedades Renales/veterinaria , Túbulos Renales/ultraestructura , Ratones Endogámicos ICR , Enfermedades de los Roedores/patología , Animales , Cromatina/ultraestructura , Femenino , Enfermedades Renales/patología , Túbulos Renales/virología , Masculino , Ratones , Reacción en Cadena de la Polimerasa , Vigilancia de Guardia/veterinaria , Pruebas SerológicasRESUMEN
Triple-negative breast cancer (TNBC) is an aggressive malignancy in which the tumors lack expression of estrogen receptor, progesterone receptor, and HER2. Hence, TNBC patients cannot benefit from clinically available targeted therapies and rely on chemotherapy and surgery for treatment. While initially responding to chemotherapy, TNBC patients are at increased risk of developing distant metastasis and have decreased overall survival compared with non-TNBC patients. A majority of TNBC tumors carry p53 mutations, enabling them to bypass the G1 checkpoint and complete the cell cycle even in the presence of DNA damage. Therefore, we hypothesized that TNBC cells are sensitive to cell-cycle-targeted combination therapy, which leaves nontransformed cells unharmed. Our findings demonstrate that sequential administration of the pan-CDK inhibitor roscovitine before doxorubicin treatment is synthetically lethal explicitly in TNBC cells. Roscovitine treatment arrests TNBC cells in the G2-M cell-cycle phase, priming them for DNA damage. Combination treatment increased frequency of DNA double-strand breaks, while simultaneously reducing recruitment of homologous recombination proteins compared with doxorubicin treatment alone. Furthermore, this combination therapy significantly reduced tumor volume and increased overall survival compared with single drug or concomitant treatment in xenograft studies. Examination of isogenic immortalized human mammary epithelial cells and isogenic tumor cell lines found that abolishment of the p53 pathway is required for combination-induced cytotoxicity, making p53 a putative predictor of response to therapy. By exploiting the specific biologic and molecular characteristics of TNBC tumors, this innovative therapy can greatly impact the treatment and care of TNBC patients. Mol Cancer Ther; 15(4); 593-607. ©2016 AACR.
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Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Doxorrubicina/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Mutaciones Letales Sintéticas , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismo , Proteína p53 Supresora de Tumor/genética , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral , Roturas del ADN de Doble Cadena , Daño del ADN , Reparación del ADN , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Quimioterapia Combinada , Femenino , Puntos de Control de la Fase G1 del Ciclo Celular/efectos de los fármacos , Puntos de Control de la Fase G1 del Ciclo Celular/genética , Eliminación de Gen , Humanos , Ratones , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
UNLABELLED: The signaling mechanisms between prostate cancer cells and infiltrating immune cells may illuminate novel therapeutic approaches. Here, utilizing a prostate adenocarcinoma model driven by loss of Pten and Smad4, we identify polymorphonuclear myeloid-derived suppressor cells (MDSC) as the major infiltrating immune cell type, and depletion of MDSCs blocks progression. Employing a novel dual reporter prostate cancer model, epithelial and stromal transcriptomic profiling identified CXCL5 as a cancer-secreted chemokine to attract CXCR2-expressing MDSCs, and, correspondingly, pharmacologic inhibition of CXCR2 impeded tumor progression. Integrated analyses identified hyperactivated Hippo-YAP signaling in driving CXCL5 upregulation in cancer cells through the YAP-TEAD complex and promoting MDSC recruitment. Clinicopathologic studies reveal upregulation and activation of YAP1 in a subset of human prostate tumors, and the YAP1 signature is enriched in primary prostate tumor samples with stronger expression of MDSC-relevant genes. Together, YAP-driven MDSC recruitment via heterotypic CXCL5-CXCR2 signaling reveals an effective therapeutic strategy for advanced prostate cancer. SIGNIFICANCE: We demonstrate a critical role of MDSCs in prostate tumor progression and discover a cancer cell nonautonomous function of the Hippo-YAP pathway in regulation of CXCL5, a ligand for CXCR2-expressing MDSCs. Pharmacologic elimination of MDSCs or blocking the heterotypic CXCL5-CXCR2 signaling circuit elicits robust antitumor responses and prolongs survival.
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Quimiocina CXCL5/genética , Células Mieloides/inmunología , Fosfohidrolasa PTEN/deficiencia , Neoplasias de la Próstata/inmunología , Proteína Smad4/deficiencia , Proteínas Adaptadoras Transductoras de Señales/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Línea Celular Tumoral , Quimiocina CXCL5/metabolismo , Progresión de la Enfermedad , Vía de Señalización Hippo , Humanos , Masculino , Ratones , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores de Interleucina-8B/genética , Receptores de Interleucina-8B/metabolismo , Transducción de Señal , Factores de Transcripción , Proteínas Señalizadoras YAPRESUMEN
OBJECTIVE: The objectives of this study were to evaluate tensile strength retention of polydioxanone as a function of time in a swine venous system and to assess the feasibility of an absorbable inferior vena cava (IVC) filter made from polydioxanone in a pilot swine study. METHODS: Twenty strands (60 cm each) of size 1 polydioxanone absorbable suture (Ethicon, Somerville, NJ) were placed in the central venous system of domestic swine. Strands were harvested at weekly intervals during 10 weeks for tensile strength testing. Results were compared with control samples obtained from an in vitro engineered circulation system containing sodium phosphate buffer solution. Three IVC filters braided from polydioxanone suture were also catheter deployed in three swine to assess absorbable IVC filter feasibility. RESULTS: Polydioxanone retained 82% tensile strength in vitro vs 79% in vivo at 35 days (P > .22), the desired prophylactic duration. For IVC filters made from polydioxanone, technical success of placement was achieved in all three filters deployed (100%). Autologous thrombus deployed inferior to the filter remained trapped in the filter until thrombus resorption, with no evidence of pulmonary emboli on follow-up computed tomography. There were no instances of caval penetration, filter-induced IVC thrombosis, filter migration, or tilt >15 degrees with imaging and clinical follow-up carried out to 32 weeks. CONCLUSIONS: Strength retention of polydioxanone suture placed in the venous system of swine is similar to earlier in vitro studies out to 10 weeks (P > .06 for all weeks) and is more than sufficient (8.20 ± 0.37 kg mean load at break for size 1) to trap thrombus. Pilot animal study suggests that an absorbable polydioxanone IVC filter can be catheter deployed to capture and to hold iatrogenically administered autologous thrombus through resorption.
Asunto(s)
Polidioxanona , Embolia Pulmonar/prevención & control , Filtros de Vena Cava , Implantes Absorbibles , Animales , Estudios de Seguimiento , Proyectos Piloto , Porcinos , Resistencia a la Tracción , Vena Cava Inferior , Trombosis de la VenaRESUMEN
The incidence of primary renal neoplasia in animals is quite low. Carcinomas are the most common primary renal tumors of dogs, cattle, and sheep. Among rabbit tumors, only uterine adenocarcinomas occur more frequently than do embryonal nephromas. However, spontaneous renal cell carcinomas in laboratory rabbits have only been reported once previously. We here report a second occurrence of a renal cell carcinoma in the laboratory rabbit.
RESUMEN
New molecular targets and intervention strategies for breaking the obesity-pancreatic cancer link are urgently needed. Using relevant spontaneous and orthotopically transplanted murine models of pancreatic cancer, we tested the hypothesis that dietary energy balance modulation impacts pancreatic cancer development and progression through an insulin-like growth factor (IGF)-I-dependent mechanism. In LSL-Kras(G12D)/Pdx-1-Cre/Ink4a/Arf(lox/+) mice, calorie restriction versus overweight- or obesity-inducing diet regimens decreased serum IGF-I, tumoral Akt/mTOR signaling, pancreatic desmoplasia, and progression to pancreatic ductal adenocarcinoma (PDAC), and increased pancreatic tumor-free survival. Serum IGF-I, Akt/mTOR signaling, and orthotopically transplanted PDAC growth were decreased in liver-specific IGF-I-deficient mice (vs. wild-type mice), and rescued with IGF-I infusion. Thus, dietary energy balance modulation impacts spontaneous pancreatic tumorigenesis induced by mutant Kras and Ink4a deficiency, the most common genetic alterations in human pancreatic cancer. Furthermore, IGF-I and components of its downstream signaling pathway are promising mechanistic targets for breaking the obesity-pancreatic cancer link.
Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Metabolismo Energético , Regulación Neoplásica de la Expresión Génica , Factor I del Crecimiento Similar a la Insulina/metabolismo , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Animales , Glucemia/metabolismo , Composición Corporal , Restricción Calórica , Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Supervivencia sin Enfermedad , Humanos , Inmunohistoquímica , Hígado/metabolismo , Masculino , Ratones , Ratones Transgénicos , Mutación , Trasplante de Neoplasias , Obesidad/complicaciones , Neoplasias Pancreáticas/complicaciones , Neoplasias Pancreáticas/metabolismo , Fenotipo , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Transducción de Señal , Factores de Tiempo , Resultado del TratamientoRESUMEN
In adult humans the prefrontal cortex possesses wider minicolumns and more neuropil space than other cortical regions. These aspects of prefrontal cortex architecture, furthermore, are increased in comparison to chimpanzees and other great apes. In order to determine the developmental appearance of this human cortical specialization, we examined the spatial organization of neurons in four cortical regions (frontal pole [Brodmann's area 10], primary motor [area 4], primary somatosensory [area 3b], and prestriate visual cortex [area 18]) in chimpanzees and humans from birth to approximately the time of adolescence (11 years of age). Horizontal spacing distance (HSD) and gray level ratio (GLR) of layer III neurons were measured in Nissl-stained sections. In both human and chimpanzee area 10, HSD was significantly higher in the postweaning specimens compared to the preweaning ones. No significant age-related differences were seen in the other regions in either species. In concert with other recent studies, the current findings suggest that there is a relatively slower maturation of area 10 in both humans and chimpanzees as compared to other cortical regions, and that further refinement of the spatial organization of neurons within this prefrontal area in humans takes place after the postweaning periods included here.