Increased expression of G9A contributes to carcinogenesis and indicates poor prognosis in hepatocellular carcinoma

Qin,Jian; Li,Qingyun; Zeng,Zhi; Wu,Ping; Jiang,Yanping; Luo,Tao; Ji,Xiang; Zhang,Qiuping; Hao,Yarong; Chen,Lang

doi:10.3892/ol.2018.8572

Increased expression of G9A contributes to carcinogenesis and indicates poor prognosis in hepatocellular carcinoma

Authors:
- Jian Qin
- Qingyun Li
- Zhi Zeng
- Ping Wu
- Yanping Jiang
- Tao Luo
- Xiang Ji
- Qiuping Zhang
- Yarong Hao
- Lang Chen
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Affiliations: Central Laboratory, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China, Department of Pathology, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China, Department of Immunology, School of Basic Medical Sciences, Wuhan University, Wuhan, Hubei 430071, P.R. China, Department of Gynecology and Obstetrics, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China, Department of Anesthesiology, Peking University Shenzhen Hospital, Shenzhen, Guangdong 518036, P.R. China, Department of Geriatric, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, P.R. China
Published online on: April 25, 2018 https://doi.org/10.3892/ol.2018.8572
Pages: 9757-9765
Copyright: © Qin et al. This is an open access article distributed under the terms of Creative Commons Attribution License.

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Abstract

Euchromatic histone‑lysine N‑methyltransferase (G9A), the primary histone methyltransferase for histone H3 Lys9, has been identified to be upregulated in numerous types of cancer. The aim of the present study was to analyze the clinical significance of G9A, and preliminarily explore its function in hepatocellular carcinoma (HCC). An increased expression level of G9A was demonstrated in the HCC samples and also in 5 publically available datasets. By analyzing GSE14520, it was revealed that its expression level was significantly associated with serum α‑fetoprotein level of patients with HCC, and may serve as a potential prognostic indicator for patients with multinodular HCC. Bioinformatics tools were utilized to predict the potential function of G9A, and the results indicated that G9A may modulate gene sets involved in RNA processing and DNA replication. G9A inhibition may suppress cell proliferation by arresting cells in G1 phase and increasing the expression level of microtubule‑associated protein light chain 3β (MAP1LC3B) in Huh7 and HepG2 cells. In addition, an inverse association between the expression of G9A and LC3B was demonstrated in HCC tumor samples in the publically available GSE14520 dataset, which indicated that G9A may also have the potential to regulate MAP1LC3B expression in HCC tumor tissues. The results of the present study led to hypothesis that the G9A expression level may be of assistance in diagnosing HCC, and be a potential therapeutic target for HCC. The results provided novel evidence for additional understanding of the crucial role of G9A in tumorigenesis.

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