Potentiation of ryanodine receptor-mediated calcium release by MAPK is responsible for epidermal transformation and carcinogenesis

• 成果类型: Article
• 署名作者: Wang, Pengcheng; Cleveland, Kristan H.; Shahid, Ayaz; Rathnayaka, Chathurika; Amirrad, Farideh; Song, Zhenpeng; Estillore, John Paul; Wang, Ruiwu; Back, Thomas G.; Chen, S. R. Wayne; Huang, Ying
• 署名单位: Western University of Health Sciences; Capital Medical University; Chapman University System; Chapman University; University of Calgary; Libin Cardiovascular Institute Of Alberta; University of Calgary
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.2505055122
• 发表日期: 2025-12-16
• 页码: e2505055122
• 关键词: JB6P+cells; calcium; carcinogenesis; TRANSFORMATION; ryanodine receptors; SPONTANEOUS CA2+ RELEASE; CARVEDILOL; mouse; activation; blocking; ap-1; inhibition; promotion; PATHWAY; analogs

摘要

Epidermal growth factor (EGF) induces anchorage-independent growth in promotion-sensitive (P+) mouse epidermal cell model JB6 primarily through activation of the MAPK/ ERK signaling pathway. The beta- blocker carvedilol inhibits EGF-promoted JB6 transformation, but the underlying mechanism is unknown. Since carvedilol suppresses overactivated ryanodine receptors (RyRs) independently of its adrenergic blocking effects, we hypothesized that EGF-promoted transformation requires RyR-mediated calcium (Ca2+) release and that carvedilol inhibits transformation via targeting RyRs. All RyR subtypes were present in epidermis and strongly upregulated by ultraviolet (UV) radiation, as demonstrated in an RyR2-tdTomato reporter mouse model. In vitro, EGF induced ERK phosphorylation and RyR2 upregulation and increased RyR agonist 4-chloro-m-cresol (4-CMC)-evoked Ca2+ release, which is inhibitable by structurally divergent RyR stabilizers and inhibitors of MAPK and PLC, but not by most beta- blockers. Expression of constitutively active K-RAS and MEK-1 or UV also potentiated 4-CMC-evoked Ca2+ release. RyR agonists and the Ca2+ ionophore ionomycin promoted JB6 transformation while RyR stabilizers, the intracellular Ca2+ chelator BAPTA/AM, and inhibitors of MAPK and PLC blocked transformation. The RyR shRNAs abolished the transformation-inhibitory effect of carvedilol. The IC50 values of five carvedilol derivatives for suppressing RyR-mediated Ca2+ release positively correlated with the IC50 values for transformation inhibition. In vivo, UV-induced DNA damage and skin inflammation were enhanced by topical 4-CMC treatment but attenuated in the RyR2-E4872Q knock-in mice in which RyR2 activity is reduced. Human skin tissue microarray analysis confirmed spatial colocalization of phospho-ERK and RyR2 in the same tumor areas. Thus, potentiation of RyR-mediated Ca2+ release by MAPK is an important pathway leading to carcinogenesis.