PUM1 knockdown prevents tumor progression by activating the PERK/eIF2/ATF4 signaling pathway in pancreatic adenocarcinoma cells

作者：Haisu Dai, Kaicheng Shen, Yishi Yang, Xingxing Su, Yuandeng Luo, Yan Jiang, Ling Shuai, Ping Zheng, Zhiyu Chen, Ping Bie · 发表于：Cell Death and Disease · 年份：2019 · DOI：10.1038/s41419-019-1839-z · 被引用次数：52 · 研究领域：RNA modifications and cancer、RNA Research and Splicing、MicroRNA in disease regulation

Pancreatic ductal adenocarcinoma (PDAC) is a malignant tumor with very poor prognosis. Therefore, it is important to fully understand the molecular mechanism underlying its occurrence and development. Pumilio RNA-binding family member 1 (PUM1) has been reported to function as an oncogene in ovarian cancer and nonsmall cell lung cancer. However, its role and mechanism in PDAC have not been fully illuminated. Here, we found that the PUM1 protein levels were higher in PDAC tissues than in adjacent tissues and that PUM1 levels were significantly associated with TNM stage and overall survival time, indicating a correlation between high PUM1 expression and poor prognosis in patients with PDAC. In vitro and in vivo assays showed that PUM1 knockdown inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT), and promoted apoptosis in MIA PaCa-2 and PANC-1 cells. Through cDNA microarrays and ingenuity pathway analysis, we found that the activation of the eIF2 signaling pathway significantly correlated with PUM1 knockdown. These results were further confirmed by the increased levels of key components of the eIF2 signaling pathway, p-PERK, p-EIF2A, and ATF4 in PUM1 knockdown cells. We also found that PUM1 levels have a significant negative correlation with p-PERK levels in PDAC tissues and that PERK overexpression inhibited cell proliferation, migration, invasion, and EMT, and promoted apoptosis in vitro. Moreover, a PERK inhibitor alleviated the effe...