Relationship between Processing Body Formation, Epithelial-to-Mesenchymal Transition, and Invasion in Lung Adenocarcinoma

Lung cancer is the leading cause of cancer-related deaths in the United States, largely due to its ability to metastasize. Epithelial-to-mesenchymal transition (EMT) is a process that enhances the ability of cells to lose their cell-cell contacts, invade, and enter the blood stream which are essential during metastasis. Many transcriptional gene programs are altered during EMT such as activation of mesenchymal transcription factors, like ZEB1, and enhanced response to the TGFβ1 cytokine. In oncogenic contexts, TGFβ1 enhances the formation of processing-bodies (P-bodies) where P-body proteins are required for invasion in multiple cancerous cell lines. P-bodies are a type of ribonucleoprotein (RNP) granule that assist in post-transcriptional gene regulation by storing or degrading mRNAs. However, the role of P-bodies has not been examined in lung cancer. This led to the hypothesis that EMT induces P-body formation where P-bodies reciprocally regulate EMT and invasion in lung cancer cells. Here, the author describes novel discoveries on the strong correlation between P-body formation and various EMT mechanisms in lung cancer cells despite P-bodies being non-essential for EMT or invasion. This study provides a foundation for future research to elucidate the mechanistic function of P-bodies during EMT in cancer progression.