Cell migration is a complex process, tightly regulated during embryonic development and abnormally activated during cancer metastasis. RAS-dependent signaling is a major nexus controlling essential cell parameters including proliferation, survival, and migration, utilizing downstream effectors such as the PI3K/AKT signaling pathway. In melanoma, oncogenic mutations frequently enhance RAS, PI3K/AKT, or MAP kinase signaling and trigger other cancer hallmarks among which the activation of metabolism regulators. PFKFB4 is one of these critical regulators of glycolysis and of the Warburg effect. Here, however, we explore a novel function of PFKFB4 in melanoma cell migration. We find that PFKFB4 interacts with ICMT, a posttranslational modifier of RAS. PFKFB4 promotes ICMT/RAS interaction, controls RAS localization at the plasma membrane, activates AKT signaling and enhances cell migration. We thus provide evidence of a novel and glycolysis-independent function of PFKFB4 in human cancer cells. This unconventional activity links the metabolic regulator PFKFB4 to RAS-AKT signaling and impacts melanoma cell migration.

Cell migration is a complex process, tightly regulated during embryonic development and abnormally activated during cancer metastasis. RAS-dependent signaling is a major nexus controlling essential cell parameters such as proliferation, survival and migration using downstream effectors among which the PI3K/AKT signaling. In melanoma, oncogenic mutations frequently enhance RAS, PI3K/AKT or MAP kinase signaling, in addition to other cancer hallmarks including the activation of metabolism regulators such as PFKFB4, a critical regulator of glycolysis and Warburg effect. Here, we explore a novel function of PFKFB4 in melanoma cell migration. We find that instead of acting as a kinase as recorded in glycolysis, PFKFB4 interacts with ICMT, a post-translational modifier of RAS. PFKFB4 promotes ICMT/RAS interaction, controls RAS addressing at the plasma membrane, activates AKT signaling and enhances cell migration. We thus evidence a novel glycolysis-independent function of PFKFB4 in human cancer cells. This unconventional activity links the metabolic regulator PFKFB4 to RAS-AKT signaling and impacts melanoma cell migration.Highlights.-PFKFB4, a known regulator of glycolysis, displays an unconventional role in melanoma cell migration.-PFKFB4 interacts with ICMT by protein-protein interactions and promotes RAS addressing at the plasma membrane.-PFKFB4 and ICMT cooperation modulates AKT signaling and controls melanoma cell migration.