RESUMEN
Taxol is commonly used chemotherapy regimen for esophageal squamous cell carcinoma (ESCC). Study of the underlying mechanisms of Taxol chemoresistance provides better understanding of esophageal cancer treatment and may provide a rational molecular target for diagnosis and intervention. Here we showed FBXO31, which was reported to be highly expressed in ESCC and significantly associated with poor prognosis, could regulate ESCC chemosensitivity to Taxol. Silencing of FBXO31 in ESCC cells sensitized cells to Taxol treatment, evidenced by FACS analysis and TUNEL assay, showing as an increased apoptotic population in FBXO31-knockdown cells compared to the control cells. The mass spectrometry data and coimmunoprecipitation results showed FBXO31 could bind with cofilin-1. Cofilin-1 knockdown in FBXO31-overexpression cells reversed FBXO31-induced suppression of cell apoptosis, suggesting FBXO31-mediated Taxol chemoresistance is associated with cofilin-1. Furthermore, in vivo experiments confirmed that knockdown of FBXO31 sensitized ESCC to Taxol treatment. This finding substantiated a pivotal role of FBOX31 in ESCC chemoresistance, indicating that FBXO31 may be a potential indicator or target for drug resistance in ESCC.
Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Cofilina 1/genética , Resistencia a Antineoplásicos/genética , Neoplasias Esofágicas/genética , Carcinoma de Células Escamosas de Esófago/genética , Proteínas F-Box/genética , Paclitaxel/farmacología , Proteínas Supresoras de Tumor/genética , Animales , Apoptosis/genética , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Cofilina 1/metabolismo , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/metabolismo , Carcinoma de Células Escamosas de Esófago/patología , Proteínas F-Box/antagonistas & inhibidores , Proteínas F-Box/metabolismo , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Ratones , Ratones Desnudos , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Transducción de Señal , Proteínas Supresoras de Tumor/antagonistas & inhibidores , Proteínas Supresoras de Tumor/metabolismo , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Until recently, it was considered axiomatic that the skull of lizards and snakes arose from that of a diapsid ancestor by loss of the lower temporal bar. The presence of the bar in the living New Zealand Tuatara, Sphenodon, was thus considered primitive, corroborating its status as a 'living fossil'. A combination of new fossils and rigorous phylogeny has demonstrated unequivocally that the absence of the bar is the primitive lepidosaurian condition, prompting questions as to its function. Here we describe new material of Tianyusaurus, a remarkable lizard from the Late Cretaceous of China that is paradoxical in having a complete lower temporal bar and a fixed quadrate. New material from Jiangxi Province is more complete and less distorted than the original holotype. Tianyusaurus is shown to be a member of the Boreoteiioidea, a successful clade of large herbivorous lizards that were dispersed through eastern Asia, Europe and North America in the Late Cretaceous, but disappeared in the end-Cretaceous extinction. A unique combination of characters suggests that Tianyusaurus took food items requiring a large gape.