Signal transduction pathways involved in OXER1-dependent cell migration

ISABEL NEUMAN; MARIANA COOKE; NICOLÁS AGUSTÍN LEMIÑA; MARCELO KAZANIETZ; FABIANA CORNEJO MACIEL

Mar del Plata

Congreso; LXIII Reunión Anual de la Sociedad Argentina de Investigación Clínica (SAIC); 2018

Sociedad Argentina de Investigación Clínica

Among lipoxygenase products of arachidonic acid metabolism, 5-HETE, 5-HPETE and 5-oxo-ETE, act through a membrane receptor called OXER1. We found that human adrenocortical H295R cells express OXER1 and that, in this cell type, this receptor is involved in PKA- and PKC-dependent stimulation of steroidogenesis.Other authors have postulated that 5-oxo-ETE is a potent activator of human neutrophil migration and prostate cancer cell proliferation. Both effects are mediated by the activation of this receptor. Using a H295R cell line stably overexpressing OXER1, we found that 5-oxo-ETE, agonist of OXER1, produced an increase in cell migration and proliferation. We also detected increased migration in the wild-type cells. In this work we studied the signal transduction pathways involved in the action of 5-oxo-ETE on H295R cells.H295R cells were cultured under different conditions, cell migration was evaluated by measuring wound healing 24 h after scratch and Western blot assays were performed using specific antibodies that recognize intermediates in different signal transduction pathways.Cell migration was differently affected when inhibitors of different signal transduction pathways were used: while no effect was observed in 5-oxo-ETE-induced migration using an inhibitor of PI3K/AKT pathway, an increase was found using a PKA inhibitor and a reduction was produced by inhibition of ERK1/2 and P38. In accordance with this, Western blot analyses revealed a time-dependent elevation in ERK1/2 and P38 phosphorylation after 5-oxo-ETE stimulation, while pAKT levels remained constant.In conclusion, OXER1 activation in H295R cells is involved not only in PKA- and PKC-dependent activation of steroidogenesis, but also in other cell functions such as migration through other signal transduction pathways.