Nucleotide P2Y1 receptor regulates EGF receptor mitogenic signaling and expression in epithelial cells

Abstract

Epidermal growth factor receptor (EGFR) function is transregulated by a variety of stimuli, including agonists of certain G-protein-coupled receptors (GPCRs). One of the most ubiquitous GPCRs is the P2Y1 receptor (P2RY1, hereafter referred to as P2Y1R) for extracellular nucleotides, mainly ADP. Here, we show in tumoral HeLa cells and normal FRT epithelial cells that P2Y1R broadcasts mitogenic signals by transactivating the EGFR. The pathway involves PKC, Src and cell surface metalloproteases. Stimulation of P2Y1R for as little as 15-60 minutes triggers mitogenesis, mirroring the half-life of extracellular ADP. Apyrase degradation of extracellular nucleotides and drug inhibition of P2Y1R, both reduced basal cell proliferation of HeLa and FRT cells, but not MDCK cells, which do not express P2Y1R. Thus, cell-released nucleotides constitute strong mitogenic stimuli, which act via P2Y1R. Strikingly, MDCK cells ectopically expressing P2Y1R display a highly proliferative phenotype that depends on EGFR activity associated with an increased level of EGFR, thus disclosing a novel aspect of GPCR-mediated regulation of EGFR function. These results highlight a role of P2Y1R in EGFR-dependent epithelial cell proliferation. P2Y1R could potentially mediate both trophic stimuli of basally released nucleotides and first-line mitogenic stimulation upon tissue damage. It could also contribute to carcinogenesis and serve as target for antitumor therapies.

Coordinate pathways for nucleotide and EGF signaling in cultured adult neural progenitor cells

“…It remains questionable whether the consensus motif-like C-terminal domain KPPTEPTPSP (aa 321-330) of the mouse P2Y 2 receptor is functional. P2Y 1 -induced transactivation of the EGF receptor was recently reported for tumoral HeLa cells and FRT epithelial cells (Buvinic et al, 2007). At present, the mechanism leading to the potential transactivation of the EGF receptor by ADPβS has not been defined.…”

β-Arrestin Mediates β1-Adrenergic Receptor-Epidermal Growth Factor Receptor Interaction and Downstream Signaling

“…The key signaling components required for EGFR transactivation following ␤1AR stimulation include: 1) C-terminal phosphorylation of activated ␤1ARs by GRK5/6, and 2) recruitment of both ␤-arrestins 1 and 2 to phosphorylated ␤1ARs. Recruitment of ␤-arrestins to activated ␤1ARs allow subsequent activation of c-Src and matrix metalloproteinases, cleavage of HB-EGF and activation of EGFR, processes that contribute to transactivation pathways defined for other 7TMRs (2)(3)(4)(5)(6)(7). Trafficking of EGFR has been shown to be critical in defining downstream signaling pathways regulated by ligand-induced activation (8).…”

Interaction of purinergic receptors with GPCRs, ion channels, tyrosine kinase and steroid hormone receptors orchestrates cell function

“…Strikingly, the canine kidney epithelial cell line which ectopically expresses P2Y 1 receptors displays a highly proliferative phenotype that depends on EGFR activity associated with an increased level of EGFR. This discloses a novel aspect of GPCRmediated regulation of EGFR function [77]. Similarly, an in vitro wound healing assay performed in human corneal and BEAS 2B (human bronchial) epithelial cells suggested that ATP released as a consequence of the wound triggers EGFR transactivation resulting in the stimulation of the PI3K and ERK signalling pathways to lead wound closure [78].…”

“…This could be explained by the fact that the EGFR function is transregulated by a variety of stimuli, including agonists of certain GPCRs [77]. Different P2Y receptor subtypes have been involved in the transactivation of the EGFR in normal and cancer cells.…”