RESUMO
Lipocalin 24p3 plays a direct role in iron transport and regulates the levels of important proteins of the iron metabolism. Iron-loaded 24p3 binds to its specific receptor (24p3R) on the cell surface. Upon binding to its receptor, 24p3 is internalized into the cell, where it releases its bound iron. Iron-free 24p3 can withdraw iron from inside the cell to the outside by a reverse mechanism. We analyzed the role of the murine 24p3 gene Lcn2 (alias 24p3) as a target of the Wnt pathway. In cells with activated Wnt pathway, the levels of 24p3 protein and RNA were decreased. The withdrawal of iron led to 24p3 downregulation, and iron addition to iron-deprived cells induced 24p3 expression. Despite its strong inhibitory effect on 24p3 expression, Wnt pathway activation had no effect on the intracellular iron level. In cells with nonactivated Wnt pathway, we found an as yet unidentified transcript of 24p3R. Our results indicate independent regulation of 24p3 expression by the Wnt pathway and by the intracellular iron level. Differential splicing of the 24p3R transcript, depending on the activation state of the Wnt pathway, may modify the function of 24p3.
Assuntos
Proteínas de Fase Aguda/genética , Proteínas de Fase Aguda/metabolismo , Ferro/metabolismo , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Proteínas Wnt/metabolismo , Animais , Sequência de Bases , DNA Complementar/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Quelantes de Ferro/farmacologia , Lipocalina-2 , Lipocalinas , Camundongos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , CoelhosRESUMO
The Wnt pathway regulates cell proliferation, mobility and differentiation. Among the many Wnt target genes is CCND1 which codes for cyclin D1. Cyclin D1, in complex with cdk4 and cdk6, regulates G1/S phase transition during cell cycle. Independently of CDK, cyclin D1 also regulates the migration of macrophages. Here we analyzed the effects of cyclin D1 on the migration of cancer cell lines using the transwell migration and scratch assays. We also tested the effect of cyclin D1 and ß-catenin on E-cadherin-mediated cell-cell contacts. Our results show that the Wnt pathway promotes cellular migration via its target gene cyclin D1. Moreover we show that cyclin D1 influences the actin cytoskeleton and destabilizes adherens junctions.
Assuntos
Ensaios de Seleção de Medicamentos Antitumorais/métodos , Genes ras/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sulindaco/análogos & derivados , Proteínas de Peixe-Zebra , Animais , Anexina A5/análise , Anexina A5/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Apoptose/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Linhagem Celular , Linhagem Celular Transformada , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Transformação Celular Neoplásica/genética , Técnicas de Química Combinatória , Relação Dose-Resposta a Droga , Células Epiteliais/efeitos dos fármacos , Genes ras/genética , Genes ras/fisiologia , Concentração Inibidora 50 , Microscopia de Fluorescência , Fenótipo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/fisiologia , Transdução de Sinais/fisiologia , Relação Estrutura-Atividade , Sulindaco/química , Sulindaco/farmacologia , Proteínas WntRESUMO
Metabolites of the non-steroidal anti-inflammatory drug Sulindac inhibit cell proliferation by affecting several intracellular signaling pathways including the tumorigenic Ras/Raf/MAPK pathway. Here, we report the synthesis of eight new indene derivatives derived from the Sulindac structure, and present data on their anti-proliferative properties and their effects on the p21ras protein.