1. NF-κB-activated SPRY4-IT1 promotes cancer cell metastasis by downregulating TCEB1 mRNA via Staufen1-mediated mRNA decay
- Author
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Ming Zhang, Minjie Wei, Qiang Zhang, Longyang Jiang, Miao He, Lin Zhao, Qiutong Guan, Yalun Li, and Jingdong Zhang
- Subjects
0301 basic medicine ,Untranslated region ,Cell biology ,Cancer Research ,RNA Stability ,Elongin ,Biology ,Article ,Metastasis ,03 medical and health sciences ,0302 clinical medicine ,Alu Elements ,Cell Line, Tumor ,Neoplasms ,microRNA ,Genetics ,medicine ,Humans ,Neoplasm Metastasis ,3' Untranslated Regions ,Molecular Biology ,Cancer ,Neoplasm Staging ,Messenger RNA ,Binding Sites ,Competing endogenous RNA ,NF-kappa B ,RNA-Binding Proteins ,Hypoxia-Inducible Factor 1, alpha Subunit ,medicine.disease ,Immunohistochemistry ,Gene Expression Regulation, Neoplastic ,Cytoskeletal Proteins ,030104 developmental biology ,030220 oncology & carcinogenesis ,Cancer cell ,Cancer research ,RNA Interference ,RNA, Long Noncoding ,Ovarian cancer ,Signal Transduction - Abstract
Previous study demonstrated that most long non-coding RNAs (lncRNAs) function as competing endogenous RNAs or molecular sponges to negatively modulate miRNA and regulate tumor development. However, the molecular mechanisms of lncRNAs in cancer are not fully understood. Our study describes the role of the lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) in cancer metastasis by mechanisms related to Staufen1 (STAU1)-mediated mRNA decay (SMD). Briefly, we found that, high SPRY4-IT1 expression was associated with aggressiveness and poor outcome in human colorectal, breast and ovarian cancer tissues. In addition, functional assays revealed that SPRY4-IT1 significantly promoted colorectal, breast and ovarian cancer metastasis in vitro and in vivo. Mechanistically, microarray analyses identified several differentially-expressed genes upon SPRY4-IT1 overexpression in HCT 116 colorectal cancer cells. Among them, the 3′-UTR of transcription elongation factor B subunit 1 (TCEB1) mRNA can base-pair with the Alu element in the 3′-UTR of SPRY4-IT1. Moreover, SPRY4-IT1 was found to bind STAU1, promote STAU1 recruitment to the 3′-UTR of TCEB1 mRNA, and affect TCEB1 mRNA stability and expression, resulting in hypoxia-inducible factor 1α (HIF-1α) upregulation, and thereby affecting cancer cell metastasis. In addition, STAU1 depletion abrogated TCEB1 SMD and alleviated the pro-metastatic effect of SPRY4-IT1 overexpression. Significantly, we revealed that SPRY4-IT1 is also transactivated by NF-κB/p65, which activates SPRY4-IT1 to inhibit TCEB1 expression, and subsequently upregulate HIF-1α. In conclusion, our results highlight a novel mechanism of cytoplasmic lncRNA SPRY4-IT1 in which SPRY4-IT1 affecting TCEB1 mRNA stability via STAU1-mediated degradation during cancer metastasis.
- Published
- 2021