PUS7‐dependent pseudouridylation of ALKBH3 mRNA inhibits gastric cancer progression

作者：Yongxia Chang, Hao Jin, Yun Cui, Feng Yang, Kang‐Hua Chen, Wenjun Kuang, Chunxiao Huo, Zhangqi Xu, Ya Li, Aifu Lin, Bo Yang, Wei Liu, Shanshan Xie, Tianhua Zhou · 发表于：Clinical and Translational Medicine · 年份：2024 · DOI：10.1002/ctm2.1811 · 被引用次数：28 · 研究领域：RNA modifications and cancer、Peptidase Inhibition and Analysis、Ferroptosis and cancer prognosis

BACKGROUND: RNA pseudouridylation is a critical post-transcriptional modification that influences gene expression and impacts various biological functions. Despite its significance, the role of mRNA pseudouridylation in cancer remains poorly understood. This study investigates the impact of pseudouridine synthase 7 (PUS7)-mediated pseudouridylation of Alpha-ketoglutarate-dependent Dioxygenase alkB Homolog 3 (ALKBH3) mRNA in gastric cancer. METHODS: Immunohistochemistry and Western blotting were used to assess PUS7 protein levels in human gastric cancer tissues. The relationship between PUS7 and gastric cancer progression was examined using 3D colony formation assays and subcutaneous xenograft models. Real-time quantitative PCR (RT-qPCR), Western blotting, and polysome profiling assays were conducted to investigate how PUS7 regulates ALKBH3. A locus-specific pseudouridine (Ψ) detection assay was used to identify Ψ sites on ALKBH3 mRNA. RESULTS: Our findings indicate a significant reduction of PUS7 in gastric cancer tissues compared to adjacent non-tumour tissues. Functional analyses reveal that PUS7 inhibits gastric cancer cell proliferation and tumour growth via its catalytic activity. Additionally, PUS7 enhances the translation efficiency of ALKBH3 mRNA by modifying the U696 site with pseudouridine, thereby attenuating tumour growth. Importantly, ALKBH3 functions as a tumour suppressor in gastric cancer, with its expression closely correlated with PUS7 levels in tumour tissu...