Atorvastatin prevents ATP-driven invasiveness via P2X7 and EHBP1 signaling in PTEN-expressing prostate cancer cells
Menée sur des cellules de cancer de la prostate exprimant PTEN, cette étude montre que l'atorvastatine peut réduire le risque d'invasion tumorale liée aux effets de l'ATP extracellulaire en agissant sur les voies de signalisation de P2X7 et EHBP1
Epidemiological studies indicate that statins, cholesterol lowering drugs, prevent aggressive prostate cancer and other types of cancer. Employing essentially non-prostate cell lines we previously showed that statins rapidly down-regulate nuclear levels of phosphorylated Akt (pAkt) via P2X7, a purinergic receptor recently implicated in invasive growth. Here we present studies on PTEN-positive prostatic cells. We document an involvement of EH domain binding protein 1 (EHBP1), previously associated with aggressive prostate cancer and insulin-stimulated trafficking and cell migration, in P2X7 signaling. We also show that EHBP1 is essential for an anti-invasive effect of atorvastatin. Furthermore, EHBP1 interacted with P-Rex1, a guanine nucleotide exchange factor (GEF) previously implicated in invasive growth. Mevalonate did not prevent this anti-invasive effect of atorvastatin. These data indicate that atorvastatin modulates invasiveness via P2X7, EHBP1 and P-Rex1. Interestingly, the interaction between EHBP1 and P-Rex1 was not induced by extracellular ATP, the endogenous P2X7 ligand, and statins counteracted invasiveness stimulated by extracellular ATP. In support of these experimental data, a population-based genetic analysis showed that a loss of function allele in the P2X7 gene (rs3751143) associated with non-aggressive cancer, and the common allele with aggressive cancer. Our data indicate a novel signaling pathway that inhibits invasiveness and that is druggable. Statins may reduce the risk of aggressive prostate cancer via P2X7 and by counteracting invasive effects of extracellular ATP.
http://carcin.oxfordjournals.org/content/early/2014/01/20/carcin.bgu019.abstract