Departamento de Bioquímica Humana, Facultad de Medicina, Universidad de Buenos Aires, Buenos Aires, Argentina; INBIOMED, Instituto de Investigaciones Biomédicas, UBA, CONICET, Buenos Aires, Argentina.
Department of Systems Pharmacology and Translational Therapeutics, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Prostaglandins Other Lipid Mediat. 2019 Oct;144:106346. doi: 10.1016/j.prostaglandins.2019.106346. Epub 2019 Jul 10.
The OXE receptor is a GPCR activated by eicosanoids produced by the action of 5-lipoxygenase. We previously found that this membrane receptor participates in the regulation of cAMP-dependent and -independent steroidogenesis in human H295R adrenocortical carcinoma cells. In this study we analyzed the effects of the OXE receptor physiological activator 5-oxo-ETE on the growth and migration of H259R cells. While 5-oxo-ETE did not affect the growth of H295R cells, overexpression of OXE receptor caused an increase in cell proliferation, which was further increased by 5-oxo-ETE and blocked by 5-lipoxygenase inhibition. 5-oxo-ETE increased the migratory capacity of H295R cells in wound healing assays, but it did not induce the production of metalloproteases MMP-1, MMP-2, MMP-9 and MMP-10. The pro-migratory effect of 5-oxo-ETE was reduced by pharmacological inhibition of the MEK/ERK1/2, p38 and PKC pathways. 5-oxo-ETE caused significant activation of ERK and p38. ERK activation by the eicosanoid was reduced by the "pan" PKC inhibitor GF109203X but not by the classical PKC inhibitor Gö6976, suggesting the involvement of novel PKCs in this effect. Although H295R cells display detectable phosphorylation of Ser299 in PKCδ, a readout for the activation of this novel PKC, treatment with 5-oxo-ETE per se was unable to induce additional PKCδ activation. Our results revealed signaling effectors activated by 5-oxo-ETE in H295R cells and may have significant implications for our understanding of OXE receptor in adrenocortical cell pathophysiology.
OXE 受体是一种 G 蛋白偶联受体，可被 5-脂氧合酶作用产生的类花生酸激活。我们之前发现，这种膜受体参与调节人 H295R 肾上腺皮质癌细胞中的 cAMP 依赖性和非依赖性类固醇生成。在这项研究中，我们分析了 OXE 受体生理激活剂 5-氧代-ETE 对 H259R 细胞生长和迁移的影响。虽然 5-氧代-ETE 不影响 H295R 细胞的生长，但 OXE 受体的过表达导致细胞增殖增加，5-氧代-ETE 进一步增加了这种增殖，而 5-脂氧合酶的抑制则阻断了这种增加。5-氧代-ETE 增加了 H295R 细胞在划痕愈合试验中的迁移能力，但它不会诱导金属蛋白酶 MMP-1、MMP-2、MMP-9 和 MMP-10 的产生。MEK/ERK1/2、p38 和 PKC 通路的药理学抑制降低了 5-氧代-ETE 的促迁移作用。5-氧代-ETE 导致 ERK 和 p38 的显著激活。PKC 的“泛”抑制剂 GF109203X 降低了该类花生酸对 ERK 的激活，但经典 PKC 抑制剂 Gö6976 没有降低，这表明在这种作用中涉及新型 PKC。尽管 H295R 细胞显示出 PKCδ中 Ser299 的磷酸化可作为新型 PKC 激活的指标，但 5-氧代-ETE 本身的处理并不能诱导额外的 PKCδ 激活。我们的结果揭示了 5-氧代-ETE 在 H295R 细胞中激活的信号转导效应器，这可能对我们理解 OXE 受体在肾上腺皮质细胞病理生理学中的作用具有重要意义。
