Up-regulation of IGF2BP2 by multiple mechanisms in pancreatic cancer promotes cancer proliferation by activating the PI3K/Akt signaling pathway

BACKGROUND: The survival of pancreatic cancer patients remains poor. However, the underlying molecular mechanism and new therapeutic target of pancreatic cancer are still needed to be found. Many studies have shown that the IGF2 mRNA-binding protein 2 (IGF2BP2) plays oncogenic roles in cancers. However, the clinical significance, role and molecular mechanisms of IGF2BP2 in pancreatic cancer remain unclear. METHODS: The expression of IGF2BP2 and miR-141 was detected in pancreatic cancer, and clinical significances were analyzed by statistical analysis. The function of IGF2BP2 and miR-141 was determined in vitro and in vivo, and the underlying mechanism was investigated. The gene copy number variation (CNV) of IGF2BP2 was analyzed based on The Cancer Genome Atlas (TCGA) dataset. microRNAs (miRNAs) regulating IGF2BP2 were predicted by online tools and confirmed by experiments. RESULTS: IGF2BP2 is overexpressed in pancreatic cancer tissues compared with control tissues. Upregulation of IGF2BP2 predicts shorter overall survival (OS) in pancreatic cancer patients by statistical analysis. IGF2BP2 overexpression is partially due to genomic amplification. Bioinformatics analyses and validation experiments showed that IGF2BP2 is a direct target of miR-141. A negative correlation between IGF2BP2 mRNA expression and the expression of miR-141 was observed in pancreatic cancer tissues and more importantly, reexpression of miR-141 rescued the oncogenic role of IGF2BP2. Moreover, upregulating IGF2BP2 expression promotes pancreatic cancer cell growth by activating the PI3K/Akt signaling pathway in vitro and in vivo. CONCLUSIONS: We comprehensively reveal the oncogenic role of IGF2BP2 in pancreatic cancer carcinogenesis and confirm that genomic amplification and the silencing of miR-141 contribute to its activation. Our findings highlight that IGF2BP2 may be a promising molecular target for the treatment of pancreatic cancer.