Yang Yang, Yan Yu, Chen Zhen, Hu Jie, Wang Kai, Tang Ni, Li Xiaosong, Zhou Zhi
Key Laboratory of Molecular Biology for Infectious Diseases (Ministry of Education), Institute for Viral Hepatitis, Department of Infectious Diseases, The Second Affiliated Hospital, Chongqing Medical University, Chongqing, China.
Clinical Molecular Medicine Testing Center, The First Affiliated Hospital, Chongqing Medical University, Chongqing, China.
J Clin Transl Hepatol. 2021 Apr 28;9(2):160-168. doi: 10.14218/JCTH.2020.00105. Epub 2021 Mar 8.
Chronic hepatitis B virus (HBV) infection is a global public health challenge. HBV reactivation usually occurs in cancer patients after receiving cytotoxic chemotherapy or immunosuppressive therapies. Romidepsin (FK228) and vorinostat (SAHA) are histone deacetylase inhibitors (HDACi) approved by the Food and Drug Administration as novel antitumor agents. The aim of this study was to explore the effects and mechanisms of HDACi treatment on HBV replication.
To assess these effects, human hepatoma cell lines were cultured and cell viability after FK228 or SAHA treatment was measured by the CCK-8 cell counting kit-8 assay. Then, HBV DNA and RNA were quantified by real-time PCR and Southern blotting. Furthermore, analysis by western blotting, enzyme-linked immunosorbent assay (ELISA), immunohistochemistry, and flow cytometry was performed.
FK228/SAHA treatment significantly promoted HBV replication and biosynthesis in both HBV-replicating cells and HBV-transgenic mouse model. Flow cytometry assay indicated that FK228/SAHA enhanced HBV replication by inducing cell cycle arrest through modulating the expression of cell cycle regulatory proteins. In addition, simultaneous inhibition of HDAC1/2 by FK228 promoted HBV replication more effectively than the broad spectrum HDAC inhibitor SAHA.
Overall, our results demonstrate that cell cycle blockage plays an important role in FK228/SAHA-enhanced HBV replication, thus providing a potential avenue for rational use of HDACi in patients with chronic hepatitis B.
慢性乙型肝炎病毒（HBV）感染是一项全球性的公共卫生挑战。HBV再激活通常发生在癌症患者接受细胞毒性化疗或免疫抑制治疗之后。罗米地辛（FK228）和伏立诺他（SAHA）是美国食品药品监督管理局批准的新型抗肿瘤药物——组蛋白去乙酰化酶抑制剂（HDACi）。本研究的目的是探讨HDACi治疗对HBV复制的影响及其机制。
为评估这些影响，培养人肝癌细胞系，并用CCK-8细胞计数试剂盒-8检测法测定FK228或SAHA处理后的细胞活力。然后，通过实时PCR和Southern印迹法对HBV DNA和RNA进行定量分析。此外，还进行了蛋白质免疫印迹分析、酶联免疫吸附测定（ELISA）、免疫组织化学和流式细胞术分析。
FK228/SAHA处理在HBV复制细胞和HBV转基因小鼠模型中均显著促进了HBV复制和生物合成。流式细胞术检测表明，FK228/SAHA通过调节细胞周期调节蛋白的表达诱导细胞周期停滞，从而增强HBV复制。此外，与广谱HDAC抑制剂SAHA相比，FK228同时抑制HDAC1/2能更有效地促进HBV复制。
总体而言，我们的结果表明细胞周期阻滞在FK228/SAHA增强HBV复制中起重要作用，从而为慢性乙型肝炎患者合理使用HDACi提供了一条潜在途径。
