HBx-induced HSPA8 stimulates HBV replication and suppresses ferroptosis to support liver cancer progression.
Yufei WangMan ZhaoLina ZhaoYu GengGuanghao LiLin ChenJingxuan YuHongfeng YuanHuihui ZhangHaolin YunYing YuanGuowen WangJinyan FengLiang XuShuai WangChunyu HouGuang YangNing-Ning ZhangWei LuXiaodong ZhangPublished in: Cancer research (2023)
Hepatitis B virus (HBV) infection is a major driver of hepatocarcinogenesis. Ferroptosis is a type of iron-mediated cell death that can suppress liver transformation. Previous studies have linked HBV to ferroptosis in liver fibrosis and acute liver failure. However, whether ferroptosis is involved in HBV-mediated liver cancer is poorly understood. Here, we identified heat shock protein family A member 8 (HSPA8) as a crucial host factor that modulates HBV replication and ferroptosis in liver cancer. Hepatitis B X protein (HBx) upregulated HSPA8 by coactivating the transcription factor heat shock factor 1 (HSF1) in cells. HSPA8 enhanced HBV replication by recruiting hepatitis B core protein (HBc) to the HBV covalently closed circular DNA (cccDNA) minichromosome, forming a positive feedback loop. Moreover, HSPA8 suppressed ferroptosis in liver cancer cells by upregulating expression of SLC7A11/GPX4 and decreasing erastin-mediated ROS and Fe2+ accumulation in cells in vitro and in vivo. Inhibition of HSPA8 reduced the growth of HBV-positive liver tumors and increased sensitivity to erastin. In conclusion, HBx-elevated HSPA8 regulates both HBV replication and ferroptosis in liver cancer. Targeting HSPA8 could be a promising strategy for controlling HBV and hepatocarcinogenesis.