RESUMEN
Optical imaging modalities are emerging as digital microscopy tools for tissue examination. The investigation of these techniques for potential applications in anatomic pathology practice has focused primarily on surgical pathology and has not included cytopathological specimens. We evaluated the feasibility of using digital confocal microscopy (CM) to examine cytopathological specimens. Smears and cell suspensions collected in RPMI solution were prepared from tissue scrapes obtained from surgical resections of breast, lung, liver, and kidney. Air-dried smears and cell pellets obtained from centrifugation of the cell suspensions were stained with 0.6 mM acridine orange and imaged with a CM platform. After completion of imaging, the smears were stained with Diff-Quik (DQ), and cell pellets were routinely processed, embedded in paraffin wax, cut, and stained with hematoxylin and eosin (H&E). We evaluated the mean time to acquire digital CM images; quality of images based on the extent of tissue recognition (0%, grade 0; 1-19%, grade 1; 20-50%, grade 2; >50%, grade 3); comparison of images with DQ- and H&E-stained specimens; and ability to make specific diagnoses. We imaged 91 smears and 52 cell pellets and acquired digital CM images within 2-3 min, with 92% and 88% of images, respectively, from smears and cell pellets showing grade 3 quality. On the basis of CM images, 8 smears (9%) and 7 cell pellets (14%) were categorized as benign, and 83 (91%) and 45 (88%), respectively, as malignant. Specific diagnoses were made by using digital CM images of smears and cell pellets that matched accurately with corresponding DQ- and H&E-stained preparations. The results of our first feasibility study clearly indicated the utility of CM as a next-generation digital microscopy tool for evaluating cytology specimens. Prospective clinical studies are warranted for validating our findings for potential incorporation into cytopathological clinical practice.
Asunto(s)
Patología Quirúrgica , Estudios de Factibilidad , Hematoxilina , Humanos , Microscopía Confocal/métodos , Patología Quirúrgica/métodos , Estudios ProspectivosRESUMEN
BACKGROUND: Patients with chronic myelogenous leukemia (CML) in blast crisis have a poor response to tyrosine kinase inhibitors designed to inhibit the breakpoint cluster region-v-Abelson murine leukemia viral oncogene homolog 1 (BCR-ABL1) oncogene. Recent work has demonstrated that heme oxygenase 1 (HO-1) expression is increased in BCR-ABL1-expressing cells and that the inhibition of HO-1 in CML leads to reduced cellular growth, suggesting that HO-1 may be a plausible target for therapy. The objective of the current study was to clarify the mechanism of HO-1 overexpression and the role of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase as a contributor to this mechanism in CML. METHODS: HO-1 expression was evaluated in bone marrow specimens from patients with CML in various stages of disease, in a transplantation-based model for CML, and in CML cell lines. Chemical and genetic inhibition of the NADPH oxidase was carried out in CML cells. RESULTS: Specimens from patients with CML in blast crisis displayed higher levels of HO-1 staining than specimens from patients with CML in chronic or accelerated phase. HO-1 up-regulation in BCR-ABL1-expressing cells was suppressed by diphenyleneiodonium (DPI), a chemical inhibitor of the NADPH oxidase. Targeting the NADPH oxidase through RNA interference (RNAi) to Ras-related C3 botulinum toxin substrate 1 (Rac1), a dominant-negative Rac1 construct or an inhibitor of Rac1 activity also blunted HO-1 protein expression. Moreover, inhibition of the NADPH oxidase by RNAi directed toward the 47-kd cytosolic subunit of Nox (p47phox) similarly abrogated HO-1 levels. CONCLUSIONS: BCR-ABL1 expression up-regulated HO-1, a survival factor for CML cells. This up-regulation was more pronounced in blast crisis CML relative to early stage disease and was mediated by the NADPH oxidase components Rac1 and p47phox. The expression of p47phox was increased in BCR-ABL1-expressing cells.
Asunto(s)
Hemo-Oxigenasa 1/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/metabolismo , NADPH Oxidasas/metabolismo , Animales , Crisis Blástica/genética , Médula Ósea/metabolismo , Línea Celular Tumoral , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/genética , Ratones , NADPH Oxidasas/antagonistas & inhibidores , Trasplante de Neoplasias , Compuestos Onio/farmacología , Especies Reactivas de Oxígeno/metabolismo , Trasplante Heterólogo , Regulación hacia ArribaRESUMEN
We have previously shown in the post ischemic gut that enteral arginine enhanced injury and inflammation via c-Jun/AP-1 and abrogated peroxisome proliferator-activated receptor (PPAR) γ activity. In the current study, we investigated the mechanism by which arginine inhibited PPARγ in vitro in rat small bowel epithelial IEC-6 cells. Arginine repressed PPARγ transcriptional activity in a time and dose-dependent fashion. Furthermore, downregulation of PPARγ by arginine involved phosphorylation of c-Jun that occurred before to changes in PPARγ transcriptional activity. Silencing of c-Jun increased PPARγ beyond that of nonsilenced cells and was not mitigated by arginine. Using a series of blocking studies, we found no relationship between arginine and the ligand-dependent binding site of PPARγ. In conclusion, arginine decreased PPARγ transcriptional activity in small bowel intestinal epithelial cells. These changes are due, in part, to phosphorylation of c-Jun and may explain the deleterious effects of enteral arginine in the post ischemic gut.
Asunto(s)
Arginina/farmacología , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , PPAR gamma/genética , PPAR gamma/metabolismo , Transcripción Genética/efectos de los fármacos , Animales , Arginina/metabolismo , Sitios de Unión , Línea Celular , Células Epiteliales/metabolismo , Proteínas Quinasas JNK Activadas por Mitógenos/genética , Fosforilación , Interferencia de ARN , ARN Interferente Pequeño , RatasRESUMEN
Glutamine possesses gut-protective effects both clinically and in the laboratory. We have shown in a rodent model of mesenteric ischemia-reperfusion that enteral glutamine increased peroxisome proliferator-activated receptor-γ (PPAR-γ) and was associated with a reduction in mucosal injury and inflammation. The mechanism by which glutamine activates PPAR-γ is unknown, and we hypothesized that it was via a ligand-dependent mechanism. Intestinal epithelial cells, IEC-6, were co-transfected with PPAR-γ response element-luciferase promoter/reporter construct. Cells were pretreated with increasing concentrations of glutamine ± GW9662 (a specific antagonist of PPAR-γ) and analyzed for PPAR-γ response element luciferase activity as an indicator of PPAR-γ activation. PPAR-γ nuclear activity was assessed by electrophoretic mobility shift assay. Cell lysates were subjected to tandem mass spectroscopy for measurement of prostaglandin and lipoxygenase metabolites. A time- and concentration-dependent increase in PPAR-γ transcriptional activity, but not mRNA or protein, was demonstrated. Activity was abrogated by the PPAR-γ inhibitor, GW9662, and changes in activity correlated with PPAR-γ nuclear binding. Glutamine, via degradation to glutamate, activated the metabolic by-products of the lipoxygenase and linoleic acid pathways, 15-S-hydroxyeicosatetraenoic acid and dehydrogenated 13-hydroxyoctaolecadienoic acid, known endogenous PPAR-γ ligands in the small bowel. This novel mechanism may explain the gut-protective effects of enteral glutamine.
Asunto(s)
Glutamina/metabolismo , Ácidos Hidroxieicosatetraenoicos/metabolismo , Mucosa Intestinal/citología , Ácidos Linolénicos/metabolismo , PPAR gamma/metabolismo , Animales , Células Cultivadas , PPAR gamma/agonistas , RatasRESUMEN
We previously demonstrated that enteral arginine increased c-Jun/activator protein-1 (AP-1) DNA-binding activity and iNOS expression in a rodent model of mesenteric ischemia/reperfusion (I/R). The objective of this study was to specifically investigate the role of AP-1 in arginine's deleterious effect on the postischemic gut. We hypothesized that AP-1 inhibition would mitigate the effects of arginine. Using a rodent model of mesenteric I/R we demonstrated that gut neutrophil infiltration, activity of c-Jun/AP-1, as well as iNOS expression were increased by I/R and further increased by arginine while lessened by inhibition of c-Jun using the pharmacologic c-Jun N-terminal kinase inhibitor, SP600125. Similar results were demonstrated using a cell culture model of oxidant stress in IEC-6 cells. Importantly, effects of SP600125 were comparable to those of c-Jun silencing. Lastly, the specific iNOS inhibitor, 1400W, had no effect on either AP-1 or c-Jun. In conclusion, SP600125 attenuated the activity of c-Jun/AP-1, iNOS expression, and neutrophil infiltration induced by arginine following mesenteric I/R. Our data suggest that AP-1 inhibition mitigates the injurious inflammatory effects of arginine in the postischemic gut. Further investigation into the pathologic role of enteral arginine in the postischemic gut is warranted.
Asunto(s)
Antracenos/farmacología , Arginina/administración & dosificación , Arginina/farmacología , Intestino Delgado/irrigación sanguínea , Proteínas Proto-Oncogénicas c-jun/antagonistas & inhibidores , Daño por Reperfusión/patología , Factor de Transcripción AP-1/antagonistas & inhibidores , Amidinas/farmacología , Animales , Bencilaminas/farmacología , ADN/metabolismo , Nutrición Enteral , Silenciador del Gen/efectos de los fármacos , Inflamación , Intestino Delgado/efectos de los fármacos , Intestino Delgado/enzimología , Intestino Delgado/patología , Óxido Nítrico Sintasa de Tipo II/metabolismo , Unión Proteica/efectos de los fármacos , Proteínas Proto-Oncogénicas c-jun/metabolismo , ARN Interferente Pequeño/metabolismo , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/enzimología , Factor de Transcripción AP-1/metabolismoRESUMEN
BACKGROUND: Protein phosphatase 2A (PP2A, a serine/threonine phosphatase) is frequently inactivated in many types of cancer, including primary liver cancer (PLC). Genetic variations in PP2A subunits have been reported to be associated with the risk of many types of cancer but rarely in PLC. This study aims to assess the association between functional polymorphisms of PP2A subunit genes and the risk of PLC in Chinese. METHODS: In a case-control study with a total of 541 PLC patients and 547 controls in Guangxi province of Southern China, we genotyped six putatively functional polymorphisms (rs10421191G>A, rs11453459del>insG, rs1560092T>G, rs7840855C>T, rs1255722G>A and rs10151527A>C) of three PP2A subunit genes (PPP2R1A, PPP2R2A and PPP2R5E) using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry platform. RESULTS: The rs11453459insG variant genotypes (ins/ins+del/ins) of PPP2R1A were found to be significantly associated with an increased risk of PLC compared with the del/del genotype (adjusted OR = 1.290, 95% CI = 1.009-1.650), and the number of insert G allele worked in a dose-dependent manner (P trend= 0.007). The stratified analysis showed that the effects of rs11453459insG variant genotypes were more evident in the subgroup who drink pond-ditch water (adjusted OR = 3.051, 95% CI = 1.264-7.364) than those never drink (P = 0.041). The carriers of rs11453459 del/ins genotype had a significantly lower level of PPP2R1A mRNA expression in liver cancer tissues than those of the del/del genotype (P = 0.021). Furthermore, we used microcystin-LR, a carcinogen presents in the pond-ditch water, to treat human peripheral blood mononuclear cells and found that the cells from carriers of rs11453459insG variant genotypes induced more DNA oxidative damages than those from the del/del genotype carriers (P < 0.001). CONCLUSION: These findings suggest that the PPP2R1A rs11453459del>insG polymorphism is associated with an increased risk of PLC, especially for persons with a history of drinking pond-ditch water. This insertion/deletion polymorphism may be a susceptible biomarker for PLC in Chinese.
RESUMEN
Providing surgical margin information during breast cancer surgery is crucial for the success of the procedure. The margin is defined as the distance from the tumor to the cut surface of the resection specimen. The consensus among surgeons and radiation oncologists is that there should be no tumor left within 1 to maximum 2 mm from the surface of the surgical specimen. If a positive margin remains, there is substantial risk for tumor recurrence, which may also result in potentially reduced cosmesis and eventual need for mastectomy. In this paper we report a novel multimodal optical imaging instrument based on combined high-resolution confocal microscopy-optical coherence tomography imaging for assessing the presence of potential positive margins on surgical specimens. Since rapid specimen analysis is critical during surgery, this instrument also includes a fluorescence imaging channel to enable rapid identification of the areas of the specimen that have potential positive margins. This is possible by specimen incubation with a cancer specific agent prior to imaging. In this study we used a quenched contrast agent, which is activated by cancer specific enzymes, such as urokinase plasminogen activators (uPA). Using this agent or a similar one, one may limit the use of high-resolution optical imaging to only fluorescence-highlighted areas for visualizing tissue morphology at the sub-cellular scale and confirming or ruling out cancer presence. Preliminary evaluation of this technology was performed on 20 surgical specimens and testing of the optical imaging findings was performed against histopathology. The combination of the three imaging modes allowed for high correlation between optical image analysis and histological ground-truth. The initial results are encouraging, showing instrument capability to assess margins on clinical specimens with a positive predictive value of 1.0 and a negative predictive value of 0.83.
Asunto(s)
Neoplasias de la Mama , Procesamiento de Imagen Asistido por Computador/métodos , Márgenes de Escisión , Microscopía Confocal , Imagen Óptica , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Estudios de Factibilidad , Femenino , Humanos , Microscopía Confocal/instrumentación , Microscopía Confocal/métodos , Imagen Óptica/instrumentación , Imagen Óptica/métodosRESUMEN
Glutamine plays a key role in intestinal growth and maintenance of gut function, and as we have shown protects the postischemic gut (Kozar RA, Scultz SG, Bick RJ, Poindexter BJ, Desoigne R, Weisbrodt NW, Haber MM, Moore FA. Shock 21: 433-437, 2004). However, the precise mechanisms of the gut protective effects of glutamine have not been well elucidated. In the present study, RNA microarray was performed to obtain differentially expressed genes in intestinal epithelial IEC-6 cells following either 2 mM or 10 mM glutamine. The result demonstrated that specificity protein 3 (Sp3) mRNA expression was downregulated 3.1-fold. PCR and Western blot confirmed that Sp3 expression was decreased by glutamine in a time- and dose-dependent fashion. To investigate the role of Sp3, Sp3 gene siRNA silencing was performed and apoptosis was assessed. Silencing of Sp3 demonstrated a significant increase in Bcl-2 and decrease in Bax protein expression, as well as a decrease in caspase-3, -8, and -9 protein expression and activity. The protein expression of apoptosis-related proteins after hypoxia/reoxygenation was similar to that of normoxia and correlated with a decrease in DNA fragmentation. Importantly, the addition of glutamine to Sp3-silenced cells did not further lessen apoptosis, suggesting that Sp3 plays a major role in the inhibitory effect of glutamine on apoptosis. This novel finding may explain in part the gut-protective effects of glutamine.
Asunto(s)
Apoptosis/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Glutamina/farmacología , Mucosa Intestinal/citología , Factor de Transcripción Sp3/metabolismo , Animales , Apoptosis/fisiología , Caspasas/genética , Caspasas/metabolismo , Línea Celular , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Células Epiteliales/fisiología , Perfilación de la Expresión Génica , Silenciador del Gen , Genes bcl-2/fisiología , ARN Interferente Pequeño , Ratas , Factor de Transcripción Sp3/antagonistas & inhibidores , Factor de Transcripción Sp3/genéticaRESUMEN
Importance: Strategies to procure high-quality core-needle biopsy (CNB) specimens are critical for making basic tissue diagnoses and for ancillary testing. Objectives: To investigate acquisition of fluorescence confocal microscopy (FCM) images of interventional radiology (IR)-guided CNB in real time in the radiology suite and to compare the accuracy of FCM diagnoses with those of hematoxylin-eosin (H&E)-stained CNB sections. Design, Setting, and Participants: In this diagnostic study, FCM imaging of IR-guided CNBs was performed in the radiology suite at a major cancer center for patients with an imaging abnormality from August 1, 2016, to April 30, 2019. The time taken to acquire FCM images and the quality of FCM images based on percentage of interpretable tissue with optimal resolution was recorded. The FCM images were read by 2 pathologists and categorized as nondiagnostic, benign/atypical, or suspicious/malignant; these diagnoses were compared with those made using H&E-stained tissue sections. Cases with discrepant diagnosis were reassessed by the pathologists together for a consensus diagnosis. Data were analyzed from June 3 to July 19, 2019. Interventions: Each IR-guided CNB was stained with 0.6mM acridine orange, subjected to FCM imaging, and then processed to generate H&E-stained sections. Main Outcomes and Measures: Mean time taken for acquisition of FCM images, quality of FCM images based on interpretable percentage of the image, and accuracy of diagnostic categorization based on FCM images compared with H&E-stained sections. Results: A total of 105 patients (57 male [54.3%]; mean [SD] age, 63 [13] years) underwent IR-guided CNBs in a mean (SD) of 7 (2) minutes each. The FCM images showed at least 20% of the tissue with optimal quality in 101 CNB specimens (96.2%). The FCM images were accurately interpreted by the 2 pathologists in 100 of 105 cases (95.2%) (2 false-positive and 3 false-negative) and 90 of 105 cases (85.7%) (6 false-positive and 9 false-negative). A reassessment of 14 discordant diagnoses resulted in consensus diagnoses that were accurate in 101 of 105 cases (96.2%) (1 false-positive and 3 false-negative). Conclusions and Relevance: The ease of acquisition of FCM images of acceptable quality and the high accuracy of the diagnoses suggest that FCM may be useful for rapid evaluation of IR-guided CNBs. This approach warrants further investigation.
Asunto(s)
Microscopía Confocal , Microscopía Fluorescente , Neoplasias/diagnóstico por imagen , Neoplasias/patología , Imagen Óptica , Anciano , Biopsia con Aguja Gruesa , Femenino , Colorantes Fluorescentes , Humanos , Biopsia Guiada por Imagen , Masculino , Persona de Mediana Edad , Valor Predictivo de las PruebasRESUMEN
Early enteral nutrition supplemented with glutamine, arginine, omega-3 fatty acids, and nucleotides has been shown to decrease infection complications in critically injured patients. Concern has been raised, however, that under conditions of hyperinflammation, these diets may be injurious through the induction of inducible NO synthase by enteral arginine. In a rodent model of gut ischemia/reperfusion, inflammation and injury are intensified by enteral arginine and abrogated by glutamine. These findings correlate with the degree of metabolic stress imposed upon the gut by hypoperfusion. Glutamine is metabolized by the gut and therefore, can contribute back energy in the form of ATP, whereas arginine is a nonmetabolizable nutrient, using but not contributing energy. Recent data suggest that one of the molecular mechanisms responsible for the gut-protective effects of enteral glutamine is the activation of peroxisome proliferator-activated receptor gamma. This anti-inflammatory transcription factor belongs to the family of nuclear receptors, plays a key role in adipocyte development and glucose homeostasis, and has been recognized as an endogenous regulator of intestinal inflammation. Preliminary clinical studies support the use of enteral glutamine in patients with gut hypoperfusion.
Asunto(s)
Nutrición Enteral , Glutamina/metabolismo , Intestino Delgado/irrigación sanguínea , Isquemia/metabolismo , PPAR gamma/metabolismo , Animales , Humanos , Daño por Reperfusión/metabolismoRESUMEN
CONTEXT.: Rapid advances in the fields of biophotonics, computer science, and instrumentation have allowed for high-resolution imaging of biologic tissues. OBJECTIVE.: To evaluate the quality of images from an optimized confocal fluorescence microscopy (CFM) platform for rapid evaluation of small fragments of tissue, compared with hematoxylin-eosin staining. DESIGN.: Tissue fragments (up to 1.0 × 0.3 cm) were stained with 0.6 mM acridine orange for 60 seconds and imaged using a CFM platform at 488-nm and 785-nm wavelength. The imaged tissues were then fixed in formalin and processed to generate hematoxylin-eosin-stained tissue sections. The quality of CFM images was scored on a scale of 0 to 3 on the basis of the percentage of the CFM images with recognizable tissue architecture (0, 0%; 1, <20%; 2, 20%-50%; 3, >50%). The diagnoses made using CFM images were compared with those made using histopathologic analysis of the hematoxylin-eosin-stained tissue sections. RESULTS.: We imaged 118 tissue fragments obtained from 40 breast, 23 lung, 39 kidney, and 16 liver surgical excision specimens. We acquired CFM images in 2 to 3 minutes; 95.8% (113 of 118) of images showed a quality score of 3, and 4.2% (5 of 118) had a score of 2. We achieved a sensitivity of 95.5%, specificity of 97.3%, positive predictive value of 95.5%, and negative predictive value of 97.3%. CONCLUSIONS.: Our results demonstrate the suitability of the CFM platform for rapid and accurate evaluation of small tissue fragments in surgical pathology practice.
Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Microscopía Confocal/métodos , Microscopía Fluorescente/métodos , Patología Quirúrgica/métodos , Humanos , Microscopía Confocal/instrumentación , Microscopía Fluorescente/instrumentación , Patología Quirúrgica/instrumentación , Sensibilidad y EspecificidadRESUMEN
The transcription factor Forkhead box M1 (FoxM1) is overexpressed in malignant glioma. However, the functional importance of this factor in human glioma is not known. In the present study, we found that FoxM1B was the predominant FoxM1 isoform expressed in human glioma but not in normal brain tissue. The level of FoxM1 protein expression in human glioma tissues was directly correlated with the glioma grade. The level of FoxM1 protein expression in human glioblastoma tissues was inversely correlated with patient survival. Enforced FoxM1B expression caused SW1783 and Hs683 glioma cells, which do not form tumor xenografts, to regain tumorigenicity in nude mouse model systems. Moreover, gliomas that arose from FoxM1B-transfected anaplastic astrocytoma SW1783 cells displayed glioblastoma multiforme phenotypes. Inhibition of FoxM1 expression in glioblastoma U-87MG cells suppressed their anchorage-independent growth in vitro and tumorigenicity in vivo. Furthermore, we found that FoxM1 regulates the expression of Skp2 protein, which is known to promote degradation of the cell cycle regulator p27(Kip1). These results showed that FoxM1 is overexpressed in human glioblastomas and contributes to glioma tumorigenicity. Therefore, FoxM1 might be a new potential target of therapy for human malignant gliomas.
Asunto(s)
Astrocitoma/metabolismo , Astrocitoma/patología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Factores de Transcripción Forkhead/biosíntesis , Glioblastoma/metabolismo , Glioblastoma/patología , Animales , Astrocitoma/genética , Neoplasias Encefálicas/genética , Línea Celular Tumoral , Ciclina D1/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Proteína Forkhead Box M1 , Factores de Transcripción Forkhead/antagonistas & inhibidores , Factores de Transcripción Forkhead/genética , Glioblastoma/genética , Humanos , Ratones , Ratones Desnudos , Isoformas de Proteínas , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteínas Quinasas Asociadas a Fase-S/metabolismo , Trasplante HeterólogoRESUMEN
PURPOSE: To delineate a role for reactive oxygen species (ROS) induction in adaphostin-induced apoptosis in glioblastoma cells. METHODS: Three glioblastoma cell lines with different sensitivities to adaphostin were characterized for sensitivity to an oxidant, tert-butyl hydroperoxide. The degree and duration of the ROS levels was assessed in the three cell lines after adaphostin exposure. Antioxidant protein levels were evaluated by Western blotting. RESULTS: Of the three glioblastoma cell lines, the U87 cells were least sensitive to adaphostin. These cells were also least sensitive to tert-butyl hydroperoxide, indicating that sensitivity to a direct oxidant stress mirrors the cells' adaphostin sensitivities. In addition, the antioxidant N-acetylcysteine, (NAC) was protective against adaphostin-induced apoptosis. Direct measurement of intracellular peroxides showed a transient increase in the two less sensitive cell lines (U87 and LN18) which diminishes by 24 h. In contrast, U251 cells, which are most sensitive to adaphostin, display a sustained increase in the ROS levels. After the initial increase in intracellular peroxides, the heat shock protein and antioxidant heme oxygenase-1 (HO-1) was upregulated. Levels of other antioxidant proteins, such as catalase and thioredoxin, however, were not altered by adaphostin in glioblastoma cell lines. NAC attenuated HO-1 upregulation, confirming the time course analysis. CONCLUSIONS: These results suggest a primary role for ROS in adaphostin-induced apoptosis in glioblastoma. Our data indicate that the duration of intracellular ROS levels is a key factor in mediating sensitivity to adaphostin. Furthermore, upregulation of HO-1 is a novel molecular marker of adaphostin's action. The kinetics with which adaphostin upregulates HO-1 correlates with sensitivity to the drug. Taken together, our data indicate that a cell's ability to cope with ROS dictates sensitivity to adaphostin and conceivably other chemotherapies that cause redox perturbations.
Asunto(s)
Adamantano/análogos & derivados , Antineoplásicos/farmacología , Glioblastoma/tratamiento farmacológico , Hemo-Oxigenasa 1/genética , Hidroquinonas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Adamantano/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Fragmentación del ADN/efectos de los fármacos , Proteínas de Fusión bcr-abl/antagonistas & inhibidores , Glioblastoma/metabolismo , Glutatión/análisis , Humanos , ARN Mensajero/análisis , Regulación hacia ArribaRESUMEN
Purpose: Large diameter perineural prostate cancer is associated with poor outcomes. GDNF, with its coreceptor GFRα1, binds RET and activates downstream pro-oncogenic signaling. Because both GDNF and GFRα1 are secreted by nerves, we examined the role of RET signaling in prostate cancer.Experimental Design: Expression of RET, GDNF, and/or GFRα1 was assessed. The impact of RET signaling on proliferation, invasion and soft agar colony formation, perineural invasion, and growth in vivo was determined. Cellular signaling downstream of RET was examined by Western blotting.Results: RET is expressed in all prostate cancer cell lines. GFRα1 is only expressed in 22Rv1 cells, which is the only line that responds to exogenous GDNF. In contrast, all cell lines respond to GDNF plus GFRα1. Conditioned medium from dorsal root ganglia contains secreted GFRα1 and promotes transformation-related phenotypes, which can be blocked by anti-GFRα1 antibody. Perineural invasion in the dorsal root ganglion assay is inhibited by anti-GFRα antibody and RET knockdown. In vivo, knockdown of RET inhibits tumor growth. RET signaling activates ERK or AKT signaling depending on context, but phosphorylation of p70S6 kinase is markedly increased in all cases. Knockdown of p70S6 kinase markedly decreases RET induced transformed phenotypes. Finally, RET is expressed in 18% of adenocarcinomas and all three small-cell carcinomas examined.Conclusions: RET promotes transformation associated phenotypes, including perineural invasion in prostate cancer via activation of p70S6 kinase. GFRα1, which is secreted by nerves, is a limiting factor for RET signaling, creating a perineural niche where RET signaling can occur. Clin Cancer Res; 23(16); 4885-96. ©2017 AACR.
Asunto(s)
Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata/genética , Proteínas Proto-Oncogénicas c-ret/genética , Transducción de Señal/genética , Animales , Línea Celular , Línea Celular Tumoral , Células HEK293 , Humanos , Masculino , Ratones Endogámicos C57BL , Ratones SCID , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/terapia , Proteínas Proto-Oncogénicas c-ret/metabolismo , Interferencia de ARN , Tratamiento con ARN de Interferencia/métodos , Carga Tumoral/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
BACKGROUND: Intravenous tranexamic acid (TXA) is an effective adjunct after hemorrhagic shock (HS) because of its antifibrinolytic properties. TXA is also a serine protease inhibitor, and recent laboratory data demonstrated that intraluminal TXA into the small bowel inhibited digestive proteases and protected the gut. A Disintegrin And Metalloproteinase 17 (ADAM-17) and tumor necrosis factor α (TNF-α) are effective sheddases of intestinal syndecan-1, which when shed, exposes the underlying intestinal epithelium to digestive proteases and subsequent systemic insult. We therefore hypothesized that intraluminal TXA as a serine protease inhibitor would reduce intestinal sheddases and syndecan-1 shedding, mitigating gut and distant organ (lung) damage. METHODS: Mice underwent 90 minutes of HS to a mean arterial pressure of 35 ± 5 mm Hg followed by the intraluminal administration of TXA or vehicle. After 3 hours, the small intestine, lung, and blood were collected for analysis. RESULTS: Intraluminal TXA significantly reduced gut and lung histopathologic injury and inflammation compared with HS alone. Gut, lung, and systemic ADAM-17 and TNF-α were significantly increased by HS but lessened by TXA. In addition, gut and lung syndecan-1 immunostaining were preserved and systemic shedding lessened after TXA. TXA reduced ADAM-17 and TNF-α, but not syndecan-1, in TXA-sham animals compared with sham vehicles. CONCLUSION: Results of the present study demonstrate a beneficial effect of intraluminal TXA in the gut and lung after experimental HS in part because of the inhibition of the syndecan-1 shedding by ADAM-17 and TNF-α. Further studies are needed to determine if orally administered TXA could provide similar intestinal protection and thus be of potential benefit to patients with survivable hemorrhage at risk for organ injury. This is particularly relevant in patients or soldiers who may not have access to timely medical care.
Asunto(s)
Mucosa Intestinal/efectos de los fármacos , Intestino Delgado/efectos de los fármacos , Lesión Pulmonar/prevención & control , Choque Hemorrágico/tratamiento farmacológico , Ácido Tranexámico/farmacología , Proteína ADAM17/metabolismo , Animales , Ensayo de Inmunoadsorción Enzimática , Inflamación/prevención & control , Mucosa Intestinal/enzimología , Mucosa Intestinal/patología , Intestino Delgado/enzimología , Intestino Delgado/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Peroxidasa/metabolismo , Sindecano-1/metabolismo , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
AIM: To explore the expression of p53, bcl-2, bax, survivin and the cell apoptosis during the development of tree shrew hepatocellular carcinoma (HCC), the relationship between expression of these genes, its impact on HCC development, and its relation to cell apoptosis. METHODS: Tree shrew HCC was induced with aflatoxin B1 (AFB1), and regular biopsy of liver tissues was carried out and the biopsy tissues were collected during cancer inducement. Liver biopsy tissue and HCC tissue were collected from 35 pre-cancerous experimental animals at wk 30 and 60 and at the 30th-, 60th-, and 90th-wk. Liver biopsy tissues were collected from 13 blank control animals at wk 30, 60, and 90. Expression of p53, bcl-2, bax, and survivin at each stage was examined by immunohistochemistry method. Apoptotic cells were detected in situ by the terminal deoxynucleotidyl transferase-mediated nick end labeling (TUNEL) technique. RESULTS: The apoptosis rate of normal hepatic cells was extremely low, whereas it increased during the formation of HCC. Expression of the apoptosis-related genes p53, bcl-2, bax, and survivin during the formation of HCC presented an increasing tendency. Expression of p53 did not noticeably relate to that of bcl-2, bax, and survivin, whereas expression of bcl-2 and bax was closely related. In HCC, p53 did not present a distinct relation to cell apoptosis, whereas its high level expression was probably related to liver cell proliferation. Survivin negatively correlated apoptosis index, and its overexpression could inhibit cell apoptosis. CONCLUSION: Apoptosis-related genes p53, bcl-2, bax, and survivin are all related to the occurrence of HCC. The anti-apoptosis effect of bcl-2 is influenced by bax, and ratio bcl/bax reflects more correctly the extent of cell apoptosis.
Asunto(s)
Apoptosis/genética , Neoplasias Hepáticas Experimentales/genética , Neoplasias Hepáticas Experimentales/patología , Aflatoxina B1/toxicidad , Animales , Expresión Génica , Genes bcl-2 , Genes p53 , Neoplasias Hepáticas Experimentales/inducido químicamente , Proteínas Asociadas a Microtúbulos/genética , Proteínas Proto-Oncogénicas c-bcl-2/genética , Tupaiidae , Proteína X Asociada a bcl-2RESUMEN
We have shown in a rodent model of hemorrhagic shock (HS) that fresh frozen plasma (FFP) reduces lung inflammation and injury that are correlated with restitution of syndecan-1. As the gut is believed to contribute to distant organ injury and inflammation after shock, the current study sought to determine if the protective effects of plasma would extend to the gut and to elucidate the contribution of syndecan-1 to this protective effect. We also examined the potential role of TNFα, and a disintegrin and metalloproteinase (ADAM)-17, both intestinal sheddases of syndecan-1. Wild-type (WT) and syndecan-1 (KO) mice were subjected to HS followed by resuscitation with lactated Ringer's (LR) or FFP and compared with shock alone and shams. Small bowel and blood were obtained after 3â h for analysis of mucosal injury and inflammation and TNFα and ADAM-17 protein expression and activity. After HS, gut injury and inflammation were significantly increased compared with shams. Resuscitation with LR decreased both injury and inflammation that were further lessened by FFP. KO mice displayed worsened gut injury and inflammation after HS compared with WT mice, and LR and FFP equivalently inhibited injury and inflammation. Both systemic and intestinal TNFα and ADAM-17 followed similar trends, with increases after HS, reduction by LR, and a further decrease by FFP in WT but not KO mice. In conclusion, FFP decreased gut injury and inflammation after hemorrhagic shock, an effect that was abrogated in syndecan-1 mice. Plasma also decreased TNFα and ADAM-17, representing a potential mechanistic link to its protection via syndecan-1.
Asunto(s)
Enfermedades Intestinales/prevención & control , Plasma , Choque Hemorrágico/terapia , Sindecano-1/fisiología , Proteínas ADAM/metabolismo , Proteína ADAM17 , Animales , Modelos Animales de Enfermedad , Enteritis/etiología , Enteritis/metabolismo , Enteritis/patología , Enteritis/prevención & control , Enfermedades Intestinales/etiología , Enfermedades Intestinales/metabolismo , Enfermedades Intestinales/patología , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Intestino Delgado/metabolismo , Intestino Delgado/patología , Masculino , Ratones Noqueados , Choque Hemorrágico/complicaciones , Choque Hemorrágico/metabolismo , Sindecano-1/deficiencia , Sindecano-1/genética , Factor de Necrosis Tumoral alfa/metabolismoRESUMEN
We have demonstrated that enteral glutamine provides protection to the postischemic gut, and that peroxisome proliferator-activated receptor-γ (PPARγ) plays a role in this protection. Using Cre/lox technology to generate an intestinal epithelial cell (IEC)-specific PPARγ null mouse model, we now investigated the contribution of IEC PPARγ to glutamine's local and distant organ-protective effects. These mice exhibited absence of expression of PPARγ in the intestine but normal PPARγ expression in other tissues. After 1 h of intestinal ischemia under isoflurane anesthesia, wild-type and null mice received enteral glutamine (60 mM) or vehicle followed by 6 h of reperfusion or 7 days in survival experiments and compared with shams. Small intestine, liver, and lungs were analyzed for injury and inflammatory parameters. Glutamine provided significant protection against gut injury and inflammation, with similar protection in the lung and liver. Changes in systemic tumor necrosis factor-α reflected those seen in the injured organs. Importantly, mice lacking IEC PPARγ had worsened injury and inflammation, and glutamine lost its protective effects in the gut and lung. The survival benefit found in glutamine-treated wild-type mice was not observed in null mice. Using an IEC-targeted loss-of-function approach, these studies provide the first in vivo confirmation in native small intestine and lung that PPARγ is responsible for the protective effects of enteral glutamine in reducing intestinal and lung injury and inflammation and improving survival. These data suggest that early enteral glutamine may be a potential therapeutic modality to reduce shock-induced gut dysfunction and subsequent distant organ injury.
Asunto(s)
Células Epiteliales/efectos de los fármacos , Glutamina/uso terapéutico , Intestinos/efectos de los fármacos , PPAR gamma/metabolismo , Daño por Reperfusión/metabolismo , Animales , Glutamina/metabolismo , Inflamación , Mucosa Intestinal/metabolismo , Intestino Delgado/efectos de los fármacos , Isquemia/patología , Hígado/efectos de los fármacos , Pulmón/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , PPAR gamma/genética , Choque Séptico/terapiaRESUMEN
This is the first report on the detection of IL-18, IFN-gamma and IL-10 proteins in hepatocelllular carcinoma. In the apparently normal surrounding tissue, 13 out of 17 paired specimens showed positive immunoreactivity to IL-18 (76.5%) compared with six out of 17 in the tumour portion (35.3% of specimens). Thus, a significantly higher number of IL-18 positive specimens was found in the hepatocytes of apparently normal surrounding tissue compared with the tumour (P=0.018). In contrast, the number of specimens with positive immunoreactivity to the antibody against the Th1 cytokine, IFN-gamma expression in the hepatocytes was lower. Only one specimen from the apparently normal surrounding tissue (one out of 17; 5.9%) and three other specimens from the tumour portion (three out of 17; 17.6%) had positive immunoreactivity. Similarly, the expression of the Th2 cytokine, IL-10 in normal (four out of 17; 23.5%) and tumour portions (five out of 17; 29.4%) was also low. Thus, there did not appear to be predominant Th2 immune response as denoted by IL-10 expression. Using the Spearman correlation rank test, a significant correlation between IL-18 expression in the apparently normal surrounding tissue and high alpha-foetoprotein (AFP) levels of >350 IU/l. No correlation between IL-18 expression in the tumour portion and clinicopathological factors was found. There was also no correlation found between IL-18 and the other cytokines, namely, IFN-gamma and IL-10 expression These new findings provide additional information on the type of cytokines expressed in the tumour microenvironment and give a further insight into the role of cytokines in the pathogenesis of cancer which is critical for the development of effective immunotherapeutic approaches for cancer therapy in the future.
Asunto(s)
Carcinoma Hepatocelular/inmunología , Citocinas/inmunología , Neoplasias Hepáticas/inmunología , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/metabolismo , Citocinas/biosíntesis , Femenino , Humanos , Inmunohistoquímica , Interferón-alfa/biosíntesis , Interferón-alfa/inmunología , Interleucina-10/biosíntesis , Interleucina-10/inmunología , Interleucina-18/biosíntesis , Interleucina-18/inmunología , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/metabolismo , Masculino , Persona de Mediana Edad , PronósticoRESUMEN
AIM: To investigate p53 mutation and p21 expression in hepatocarcinogenesis induced by hepatitis B virus (HBV) and aflatoxin B(1) (AFB(1)) in tree shrews, and to reveal the role of these genes in hepatocarcinogenesis. METHODS: Tree shrews were divided into four groups: group A, those infected with HBV and fed with AFB(1) (n = 39); group B, those infected with HBV alone (n = 28); group C, those fed with AFB(1) alone (n = 29); and group D, normal controls (n = 20). The tree shrews underwent liver biopsies once every 15 wk. Expression of p53 and p21 proteins and genes in the biopsies and tumor tissues of the experimental tree shrews was detected, respectively, by immunohistochemistry, and by Southern blotting and reverse transcription-polymerase chain reaction and sequencing. RESULTS: The incidence of hepatocellular carcinomas (HCC) was higher in group A (66.7%) than that in group B (3.57%) and C (30%). The time of HCC occurrence was also earlier in group A than that in group C (120.0+/-16.6 wk vs 153.3+/-5.8 wk, respectively, P<0.01). p53 protein was not detected by immunohistochemistry in all groups before the 75(th) wk of the experiment. At the 105(th) wk, the positive rates fo p53 were 78.6%, 60% and 71.4% in groups A, B and C, respectively, which were significantly higher than that in group D (10%) (all P<0.05). An abnormal band of p53 gene was observed in groups A and C. The mutation points of p53 gene in tree shrews with HCC were at codons 275, 78 and 13. The nucleotide sequence and amino acid sequence of tree shrew's wild-type p53 showed 91.7% and 93.4% homologies with those of human p53, respectively. The immunopositivity for p21 was found before HCC development. The incidence of HCC was significantly higher in tree shrews that were positive for p21 than those negative for p21 (80.0% vs 11.0%, P<0.001). The incidence of HCC in p21 positive animals in group A was significantly higher than those positive for p21 in group C (P<0.05). CONCLUSION: A remarkable synergistic effect on HCC development exists between HBV and AFB(1). p53 mutation promotes the development of HCC. HBV and AFB(1) may synergistically induce p53 gene mutation, and stimulate ras gene expression. ras gene is activated at the earlier stage during hepatocarcinogenesis. p21 protein may be an early marker, and the alterations of p53 may be a late event in the development of HCC.