Elongation factor-2 kinase (eEF-2K) expression is associated with poor patient survival and promotes proliferation, invasion and tumor growth of lung cancer

Here, we report that Eukaryotic Elongation Factor-2 kinase (eEF-2K), a member of an atypical alpha kinases family, is significantly upregulated in lung cancer cell lines and its expression is associated with shorter overall patient survival in lung cancer. Inhibition eEF-2K expression by siRNA or a chemical inhibitorsignificantly suppressed lung cancer cell proliferation, colony formation, survival, migration/invasion and tumorigenesis by inhibiting cyclin D1, Src and Mitogen-Activated Protein Kinases/Extracellular Signal-Regulated Kinase (MAPK/ERK) signaling. In vivo targeting of eEF-2K by systemically injected nanoliposomal eEF-2K siRNA resulted in a significant inhibition of lung cancer tumor xenografts in nude mice. Our results suggest, for the first time, that expression of eEF-2K is associated with poor patient prognosis and involved in regulation of critical pathways, including Src and MAPK/ERK and cyclin D1, promoting tumor growth and progression, and thus may be a novel potential therapeutic target in lung cancer.