RESUMEN
Lysophosphatidic acid (LPA) is a bioactive phospholipids and involves in various cellular events, including tumor cell migration. In the present study, we investigated LPA receptor and its transactivation to EGFR for cyclooxygenase-2 (COX-2) expression and cell migration in CAOV-3 ovarian cancer cells. LPA induced COX-2 expression in a dose-dependent manner, and pretreatment of the cells with pharmacological inhibitors of Gi (pertussis toxin), Src (PP2), EGF receptor (EGFR) (AG1478), ERK (PD98059) significantly inhibited LPA- induced COX-2 expression. Consistent to these results, transfection of the cells with selective Src siRNA attenuated COX-2 expression by LPA. LPA stimulated CAOV-3 cell migration that was abrogated by pharmacological inhibitors and antibody of EP2. Higher expression of LPA2 mRNA was observed in CAOV-3 cells, and transfection of the cells with a selective LPA2 siRNA significantly inhibited LPA-induced activation of EGFR and ERK, as well as COX-2 expression. Importantly, LPA2 siRNA also blocked LPA-induced ovarian cancer cell migration. Collectively, our results clearly show the significance of LPA2 and Gi/Src pathway for LPA-induced COX-2 expression and cell migration that could be a promising drug target for ovarian cancer cell metastasis.
Asunto(s)
Femenino , Humanos , Butadienos/farmacología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Ciclooxigenasa 2/biosíntesis , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Flavonoides/farmacología , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/antagonistas & inhibidores , Lisofosfolípidos/farmacología , Nitrilos/farmacología , Neoplasias Ováricas/metabolismo , Toxina del Pertussis/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Pirimidinas/farmacología , Receptores ErbB/antagonistas & inhibidores , Receptores del Ácido Lisofosfatídico/metabolismo , Receptores de Prostaglandina E/metabolismo , Transducción de Señal , Activación Transcripcional , Tirfostinos/farmacologíaRESUMEN
(...) Com o objetivo de abordar tais vias parasito, estudamos bioquimicamente e citoquimicamente a atividade fosfatase ácida. Parasitos tratados com os três inibidores po 1h e 24h apresetaram atividade fosfatase ácida secretada significativametne dimunuída. com a finalidade de estudar as vias de sinalização do parasito na interação com a célula hospedeira, promastigotas pré-tratados com os antagonistas foram incubados com macrófagos peritoneais. Observamos que estaurosporina 1μM inibiu, de forma significativa, a internalização e a sobrevivência intracelular dos parasitos. Nossos dados sugerem que inibidores de proteína cinases podem exercer efeitos na morfologia, infectividade e proliferação de Leishmania, bloqueando o ciclo celular desses parasitos.
Asunto(s)
Fosforilación , Técnicas In Vitro , Inhibidores Enzimáticos/metabolismo , Leishmania mexicana/enzimología , Proteína Quinasa C/fisiología , Western Blotting , Electroforesis en Gel de Poliacrilamida , Estaurosporina/farmacología , Genisteína/farmacología , Microscopía Electrónica de Transmisión , Fosforilación , Interacciones Huésped-Parásitos , Tirfostinos/farmacologíaRESUMEN
1) A beta agonist stimulated Na+ transport and decreased the intracellular Cl concentration ([Cl]c) associated with cell shrinkage via an increase in cytosolic cAMP level by activating adenylate cyclase in rat fetal distal lung epithelial (FDLE) cells. 2) Lowering [Cl-]c activated a 28-pS nonselective cation (NSC) channel by elongating the open time of the channel. 3) cAMP signals were converted to a protein tyrosine kinase (PTK)-mediated signal. 4) The PTK-mediated signal was involved in the cAMP-stimulated Na+ transport in rat FDLE cells.