m6A RNA hypermethylation-induced BACE2 boosts intracellular calcium release and accelerates tumorigenesis of ocular melanoma.

Abstract

Ocular melanoma, including uveal melanoma (UM) and conjunctival melanoma (CM), is the most common and deadly eye cancer in adults. Both UM and CM originate from melanocytes and exhibit an aggressive growth pattern with high rates of metastasis and mortality. The integral membrane glycoprotein beta-secretase 2 (BACE2), an enzyme that cleaves amyloid precursor protein into amyloid beta peptide, has been reported to play a vital role in vertebrate pigmentation and metastatic melanoma. However, the role of BACE2 in ocular melanoma remains unclear. In this study, we showed that BACE2 was significantly upregulated in ocular melanoma, and inhibition of BACE2 significantly impaired tumor progression both in vitro and in vivo. Notably, we identified that transmembrane protein 38B (TMEM38B), whose expression was highly dependent on BACE2, modulated calcium release from endoplasmic reticulum (ER). Inhibition of the BACE2/TMEM38B axis could trigger exhaustion of intracellular calcium release and inhibit tumor progression. We further demonstrated that BACE2 presented an increased level of N6-methyladenosine (m6A) RNA methylation, which led to the upregulation of BACE2 mRNA. To our knowledge, this study provides a novel pattern of BACE2-mediated intracellular calcium release in ocular melanoma progression, and our findings suggest that m6A/BACE2/TMEM38b could be a potential therapeutic axis for ocular melanoma.

• Authors: Fanglin He, Jie Yu, Jie Yang, Shaoyun Wang, Ai Zhuang, Hanhan Shi, Xiang Gu, Xiaofang Xu, Peiwei Chai, Renbing Jia
• Journal: Molecular therapy : the journal of the American Society of Gene Therapy (Mol Ther) Vol. 29 Issue 6 Pg. 2121-2133 (06 02 2021) ISSN: 1525-0024 [Electronic] United States
• PMID: 33601055 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2021 The American Society of Gene and Cell Therapy. Published by Elsevier Inc. All rights reserved.

Chemical References

• Ion Channels
• TMEM38B protein, human
• RNA
• N-methyladenosine
• Amyloid Precursor Protein Secretases
• Aspartic Acid Endopeptidases
• BACE2 protein, human
• Adenosine
• Calcium

Topics

• Adenosine (analogs & derivatives)
• Amyloid Precursor Protein Secretases (genetics, metabolism)
• Aspartic Acid Endopeptidases (genetics, metabolism)
• Calcium (metabolism)
• Cell Line, Tumor
• Cell Transformation, Neoplastic (genetics, metabolism)
• Epigenesis, Genetic
• Gene Expression Profiling
• Gene Expression Regulation, Neoplastic
• Humans
• Ion Channels (genetics, metabolism)
• Melanoma (genetics, metabolism, mortality, pathology)
• Methylation
• RNA (genetics, metabolism)
• RNA Interference
• Uveal Neoplasms (genetics, metabolism, mortality, pathology)