The Relations Of EEF2K, Autophagy And Cell Death In Non-small Cell Lung Cancer

Eukaryotic elongation factor 2 kinase (eEF2K) is well known as a Ca2+/CaM-dependent protein kinase, and eEF2 is its only known substrate. eEF2K catalyzes the phosphorylation of eEF2 on Thr56, and thereof reduces its binding capacity to ribosomes and inhibites peptide elongation. Through years of research, many types of cancer cells have been found to show highly expressed or activated eEF2K, especially in glioma and breast cancer. eEF2K expression levels affect many physiological processes, such as cell differentiation, cell cycle, autophagy, apoptosis and so on. The relationships between eEF2K and autophagy is one of the hot topics in the biological area. Researches have found that increased activity of eEF2K can induce autophagy while inhibition this autophagy can increase the potency of many drugs. However, in colon cancer cells it has been shown that inhibition of eEF2K induced autophagy did not observe increase the efficacy of MK-2206, these date suggesting that eEF2K may play different roles in different cell lines. Now the research of eEF2K in non-small cell lung cancer is still basically a blank stage. In this project, we aim to study the role of eEF2K and the relationship between eEF2K and autophagy in non-small cell lung cancer, eventually provide more substantial evidence for eEF2K as an anti-tumor target for the future.Part one:Gefitinib-induced activation of eEF2K and autophagy in non-small cell lung cancerWe found that gefitinib can significantly enhance the activity of eEF2K in the non-small cell lung cancer. By immunoprecipitation detection autophagy-related proteins P62 and LC3, immunofluorescence detection the LC3 accumulation and transmission electron microscopy detect the formation of autophagic, we found that gefitinib can significantly enhance autophagic activity in the non-small cell lung cancer. We also found some consistence in gefitinib-induced eEF2K and autophagic activity increase. These data suggest that there may be some connection between the two.Part two:The relations of eEF2K, autophagy and cell death in non-small cell lung cancer1. Inhibiting the activity of eEF2K does not influence the autophagyA484954 can inhibit eEF2K in non-small cell lung cancer at 100uM,6h. Inhibiting the activity of eEF2K have no effect on autophagy, which caused by gefitinib. Stattic also can induce eEF2K and autophagic activity increased in non-small cell lung cancer.2. The impact of autophagy and eEF2K activity on cell survivaleEF2K inhibition does not have an impact on autophagy. We detect eEF2K and autophagic activity influced on cell viability. We found that 3-MA can significantly enhance the efficacy of gefitinib, while inhibition eEF2K activity can reduce the efficacy of gefitinib, especially in high concentrations in non-small cell lung cancer. If eEF2K activity was inhibited in advance, the effect is more pronounced.3. Inhibiting eEF2K enhances the viability of NSCLC cell linesWe counted the cell number and colony number after interfering eEF2K. The results showed that eEF2K inhibition can increase cell viability and autophagic activity. However, the inhibition of eEF2K reduces autophagy and inhibits cell growth in breast cancer cells. In our study, we found inhibition eEF2K has no significant effect on gefitinib-induced autophagy. In addition, we revealed that inhibition eEF2K can induce autophagy and promote cell proliferation in non-small cell lung cancer.Significance:In this paper, we invested the biological role of eEF2K in different tumor cells and its relationship with autophagy and cell death, which is good for the development of more effective drugs.