1. EP4-induced mitochondrial localization and cell migration mediated by CALML6 in human oral squamous cell carcinoma.
- Author
-
Ishikawa, Soichiro, Umemura, Masanari, Nakakaji, Rina, Nagasako, Akane, Nagao, Kagemichi, Mizuno, Yuto, Sugiura, Kei, Kioi, Mitomu, Mitsudo, Kenji, and Ishikawa, Yoshihiro
- Subjects
PROSTAGLANDIN receptors ,CELL migration ,SQUAMOUS cell carcinoma ,CALMODULIN ,CALCIUM-dependent protein kinase ,LYMPHATIC metastasis ,PROTEIN kinases - Abstract
Lymph node metastasis, primarily caused by the migration of oral squamous cell carcinoma (OSCC) cells, stands as a crucial prognostic marker. We have previously demonstrated that EP4, a subtype of the prostaglandin E2 (PGE2) receptor, orchestrates OSCC cell migration via Ca
2+ signaling. The exact mechanisms by which EP4 influences cell migration through Ca2+ signaling, however, is unclear. Our study aims to clarify how EP4 controls OSCC cell migration through this pathway. We find that activating EP4 with an agonist (ONO-AE1-473) increased intracellular Ca2+ levels and the migration of human oral cancer cells (HSC-3), but not human gingival fibroblasts (HGnF). Further RNA sequencing linked EP4 to calmodulin-like protein 6 (CALML6), whose role remains undefined in OSCC. Through protein-protein interaction network analysis, a strong connection is identified between CALML6 and calcium/calmodulin-dependent protein kinase kinase 2 (CaMKK2), with EP4 activation also boosting mitochondrial function. Overexpressing EP4 in HSC-3 cells increases experimental lung metastasis in mice, whereas inhibiting CaMKK2 with STO-609 markedly lowers these metastases. This positions CaMKK2 as a potential new target for treating OSCC metastasis. Our findings highlight CALML6 as a pivotal regulator in EP4-driven mitochondrial respiration, affecting cell migration and metastasis via the CaMKK2 pathway. EP4 receptor enhances OSCC cell migration through increased Ca2+ signaling, linking to CALML6 and the CaMKK2 pathway. This process promotes mitochondrial function and metastasis, with CaMKK2 emerging as a potential target for OSCC treatment. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF