Tumor Suppressor 4.1N/ EPB41L1 is Epigenetic Silenced by Promoter Methylation and MiR-454-3p in NSCLC

Qin Yang; Lin Zhu; Mao Ye; Bin Zhang; Peihe Zhan; Hui Li; Wen Zou; Jing Liu

doi:10.3389/fgene.2022.805960

Tumor Suppressor 4.1N/ EPB41L1 is Epigenetic Silenced by Promoter Methylation and MiR-454-3p in NSCLC

Front Genet. 2022 Jun 20:13:805960. doi: 10.3389/fgene.2022.805960. eCollection 2022.

Authors

Qin Yang^{1

2}, Lin Zhu¹, Mao Ye^{3

4}, Bin Zhang⁵, Peihe Zhan⁵, Hui Li^{1

3

4}, Wen Zou⁶, Jing Liu¹

Affiliations

¹ Molecular Biology Research Center and Center for Medical Genetics, School of Life Sciences, Central South University, Changsha, China.
² School of Medical Laboratory, Shao Yang University, Shaoyang, China.
³ Molecular Science and Biomedicine Laboratory, College of Biology, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan University, Changsha, China.
⁴ State Key Laboratory for Chemo/Biosensing and Chemometrics, College of Biology, College of Chemistry and Chemical Engineering, Collaborative Innovation Center for Chemistry and Molecular Medicine, Hunan Univers ity, Changsha, China.
⁵ Department of Histology and Embryology, Xiangya School of Medicine, Central South University, Changsha, China.
⁶ Department of Oncology, The Second Xiangya Hospital of Central South University, Central South University, Changsha, China.

Abstract

Non-small-cell lung cancer (NSCLC) is divided into three major histological types, namely, lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), and large-cell lung carcinoma (LCLC). We previously identified that 4.1N/EPB41L1 acts as a tumor suppressor and is reduced in NSCLC patients. In the current study, we explored the underlying epigenetic mechanisms of 4.1N/EPB41L1 reduction in NSCLC. The 4.1N/EPB41L1 gene promoter region was highly methylated in LUAD and LUSC patients. LUAD patients with higher methylation level in the 4.1N/EPB41L1 gene promoter (TSS1500, cg13399773 or TSS200, cg20993403) had a shorter overall survival time (Log-rank p = 0.02 HR = 1.509 or Log-rank p = 0.016 HR = 1.509), whereas LUSC patients with higher methylation level in the 4.1N/EPB41L1 gene promoter (TSS1500 cg13399773, TSS1500 cg07030373 or TSS200 cg20993403) had a longer overall survival time (Log-rank p = 0.045 HR = 0.5709, Log-rank p = 0.018 HR = 0.68 or Log-rank p = 0.014 HR = 0.639, respectively). High methylation of the 4.1N/EPB41L1 gene promoter appeared to be a relatively early event in LUAD and LUSC. DNA methyltransferase inhibitor 5-Aza-2'-deoxycytidine restored the 4.1N/EPB41L1 expression at both the mRNA and protein levels. MiR-454-3p was abnormally highly expressed in NSCLC and directly targeted 4.1N/EPB41L1 mRNA. MiR-454-3p expression was significantly correlated with 4.1N/EPB41L1 expression in NSCLC patients (r = -0.63, p < 0.0001). Therefore, we concluded that promoter hypermethylation of the 4.1N/EPB41L1 gene and abnormally high expressed miR-454-3p work at different regulation levels but in concert to restrict 4.1N/EPB41L1 expression in NSCLC. Taken together, this work contributes to elucidate the underlying epigenetic disruptions of 4.1N/EPB41L1 deficiency in NSCLC.

Keywords: 4.1N/EPB41L1; lung adenocarcinoma (LUAD); lung squamous cell carcinoma (LUSC); methylation; miR-454-3P; non–small-cell lung cancer (NSCLC).