eIF4E phosphorylation promotes tumorigenesis and is associated with prostate cancer progression

Translational regulation plays a critical role in cell growth and proliferation, and its dysregulation results in cancer. Aberrant expression of the mRNA 5’cap-binding protein, eIF4E, has been implicated in cancer development and progression. eIF4E activity is promoted by phosphorylation. Here we show that “knock-in” mice in which eIF4E cannot be phosphorylated are resistant to tumorigenesis in a prostate cancer model. We identify multiple candidate genes involved in the resistance to oncogenic transformation. Importantly, phosphorylation of eIF4E is increased in hormone-refractory prostate cancer, the deadliest stage of the disease. Our results highlight eIF4E phosphorylation as a critical event in tumorigenesis. Comaparison of total RNA and polysomal RNA from mouse embryo fibroblasts derived from WT and eIF4E-KI (non phosphorylatable eIF4E) mice