N6-Methyladenosine-Modified ATP8B1-AS1 Exerts Oncogenic Roles in Hepatocellular Carcinoma via Epigenetically Activating MYC

Chuan Tan; Yanyan Huang; Zheng Huang; Yuanjia Ning; Lizheng Huang; Xianjian Wu; Yuan Lu; Huamei Wei; Jian Pu

doi:10.2147/JHC.S415318

N⁶-Methyladenosine-Modified ATP8B1-AS1 Exerts Oncogenic Roles in Hepatocellular Carcinoma via Epigenetically Activating MYC

J Hepatocell Carcinoma. 2023 Sep 6:10:1479-1495. doi: 10.2147/JHC.S415318. eCollection 2023.

Authors

Chuan Tan^#¹, Yanyan Huang^#², Zheng Huang^#², Yuanjia Ning², Lizheng Huang², Xianjian Wu¹, Yuan Lu¹, Huamei Wei³, Jian Pu¹

Affiliations

¹ Department of Hepatobiliary Surgery, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, People's Republic of China.
² Graduate College of Youjiang Medical University for Nationalities, Baise, People's Republic of China.
³ Department of Pathology, Affiliated Hospital of Youjiang Medical University for Nationalities, Baise, People's Republic of China.

^# Contributed equally.

Abstract

Purpose: N⁶-methyladenosine (m⁶A) modification has shown critical roles in regulating mRNA fate. Non-coding RNAs also have important roles in various diseases, including hepatocellular carcinoma (HCC). However, the potential influences of m⁶A modification on non-coding RNAs are still unclear. In this study, we identified a novel m⁶A-modified ATP8B1-AS1 and aimed to investigate the effects of m⁶A on the expression and role of ATP8B1-AS1 in HCC.

Methods: qPCR was performed to measure the expression of related genes. The correlation between gene expression and prognosis was analyzed using public database. m⁶A modification level was measured using MeRIP and single-base elongation- and ligation-based qPCR amplification method. The roles of ATP8B1-AS1 in HCC were investigated using in vitro and in vivo functional assays. The mechanisms underlying the roles of ATP8B1-AS1 were investigated by ChIRP and ChIP assays.

Results: ATP8B1-AS1 is highly expressed in HCC tissues and cell lines. High expression of ATP8B1-AS1 is correlated with poor overall survival of HCC patients. ATP8B1-AS1 is m⁶A modified and the 792 site of ATP8B1-AS1 is identified as an m⁶A modification site. m⁶A modification increases the stability of ATP8B1-AS1 transcript. m⁶A modification level of ATP8B1-AS1 is increased in HCC tissues and cell lines, and correlated with poor overall survival of HCC patients. ATP8B1-AS1 promotes HCC cell proliferation, migration, and invasion, which were abolished by the mutation of m⁶A-modified 792 site. Mechanistic investigation revealed that m⁶A-modified ATP8B1-AS1 interacts with and recruits m⁶A reader YTHDC1 and histone demethylase KDM3B to MYC promoter region, leading to the reduction of H3K9me2 level at MYC promoter region and activation of MYC transcription. Functional rescue assays showed that depletion of MYC largely abolished the oncogenic roles of ATP8B1-AS1.

Conclusion: m⁶A modification level of ATP8B1-AS1 is increased and correlated with poor prognosis in HCC. m⁶A-modified ATP8B1-AS1 exerts oncogenic roles in HCC via epigenetically activating MYC expression.

Keywords: MYC signaling; N6-methyladenosine; hepatocellular carcinoma; histone methylation; noncoding RNA.

Grants and funding

This work was supported by Guangxi science and technology project (2021AC20006) and high-level personnel project of Affiliated Hospital of Youjiang Medical University for Nationalities (R202210307).