Arginine vasopressin controls p27Kip1 protein expression by PKC activation and irreversibly inhibits the proliferation of K-Ras-dependent mouse Y1 adrenocortical malignant cells

► Inhibition of mouse Y1 malignant cells proliferation by AVP depends on PKC activation and high levels of K-Ras-GTP. ► AVP activates ERK pathway independent on PKC activity but inhibits PI3K/Akt via activation in a PKC-dependent manner. ► AVP stabilises, increases and/or maintains expression of the p27Kip1 protein antagonizing the mitogenic activity of FGF2. ► Phosphorylation of p27Kip1 protein at Ser10 and Thr187 residues is modulated by AVP ± FGF2. ► PMA mimics most AVP effects through PKC, and dependently on K-Ras malignant phenotype of Y1 cells.