LCK-14-3-3ζ-TRPM8 axis for regulating TRPM8 function/assembly promotes pancreatic cancer malignancy

Abstract

The transient receptor potential melastatin 8 (TRPM8), function as a Ca2+-permeable channel in the plasma membrane (PM). Dysfunction of TRPM8 is associated with human pancreatic cancer and several other diseases in clinical patients, but with unclear underlying mechanisms. Here, we found lymphocyte-specific protein tyrosine kinase (LCK) directly interacts with TRPM8 and potentiates TRPM8 phosphorylation at Y1022. LCK positively regulated channel function characterized by increased TRPM8 currents densities through enhancing TRPM8 multimerization. Furthermore, 14-3-3{zeta} interacted with TRPM8 and positively modulated channel multimerization. LCK significantly enhanced the binding of 14-3-3{zeta} and TRPM8, whereas mutant TRPM8-Y1022F impaired TRPM8 multimerization and the binding of TRPM8 and 14-3-3{zeta}. Knockdown of 14-3-3{zeta} impaired the regulation of LCK on TRPM8 multimerization. Additionally, TRPM8 phosphotyrosine at Y1022 feedback regulated LCK activity by inhibition of Tyr505 phosphorylation and modulation of LCK ubiquitination. Finally, we revealed the importance of TRPM8 phosphorylation at Y1022 in the proliferation, migration and tumorigenesis of pancreatic cancer cells. Our findings demonstrate that LCK-14-3-3{zeta}-TRPM8 axis for regulating TRPM8 assembly, channel function, LCK activity and providing potential therapeutic targets for pancreatic cancer.