SUMOylation-Induced Membrane Localization of TRPV1 Suppresses Proliferation and Migration in Gastric Cancer Cells
Gastric cancer (GC) remains a significant health challenge due to its high mortality rate and the limited efficacy of current targeted therapies. A critical barrier in developing more effective treatments is the lack of understanding of specific mechanisms driving GC progression. This study investigates the role of Transient Receptor Potential Vanilloid 1 (TRPV1), a non-selective cation channel known for its high Ca2+ permeability and tumor-suppressive properties in gastrointestinal cancers. Specifically, we explore the impact of SUMOylation—a dynamic and reversible post-translational modification—on TRPV1's function in GC. We demonstrate that SUMOylation of TRPV1 inhibits cell proliferation and migration in MGC-803 and AGS gastric cancer cells. By mutating amino acids near TRPV1's existing SUMO motif (slKpE), we created a bidirectional SUMO motif (E?K?E) that enhances TRPV1 SUMOylation, resulting in further suppression of GC cell proliferation and migration. In vivo studies support these findings, showing that TRPV1 SUMOylation prevents spontaneous tumorigenesis in a mouse gastric cancer model. Further investigation reveals that TRPV1 SUMOylation increases the protein's membrane expression by inhibiting its interaction with the adaptor-related protein complex 2 mu 1 subunit (AP2M1). This elevated membrane expression leads to increased intracellular Ca2+ influx, activating the AMP-activated protein kinase (AMPK) pathway, which in turn inhibits the proliferation and migration of GC cells. In conclusion, our study elucidates a novel mechanism wherein TRPV1 SUMOylation promotes its membrane expression and activates the TRPV1-Ca2+-AMPK signaling pathway, thereby inhibiting GC cell proliferation and migration. These findings enhance our understanding of the molecular dynamics in gastric cancer and could provide a new theoretical basis for clinical treatment strategies. Overall design: To explore the signaling pathway and possible regulatory molecules that affect the changes of TRPV1 SUMOylation on cell proliferation and migration, RNA lysate of gastric cancer MGC-803 cells with stable Flag-TRPV1WT and Flag-TRPV1K823R were extracter, and performed RNA-Seq