Affiliations: [a] Department of General Surgery, The First Affiliated Hospital of Xi’an Medical University, Xi’an, Shaanxi, China | [b] Department of General Surgery, Shaanxi Sengong Hospital, Xi’an, Shaanxi, China | [c] Department of General Surgery, The First Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China | [d] Department of Emergency Surgery, The Second Affiliated Hospital of Anhui Medical University, Hefei, Anhui, China | [e] Department of General Surgery, The Anhui No. 2 Provincial People’s Hospital, Hefei, Anhui, China
Correspondence:
[*]
Corresponding author: Pu Yan, Department of General Surgery, The First Affiliated Hospital of Xi’an Medical University, Xi’an 710018, Shaanxi, China. Tel.: +86 15902998251; E-mail: [email protected].
Abstract: OBJECTIVE: Colorectal cancer (CRC) is the 3rd most common cancer worldwide. Recently, long non-coding RNAs (lncRNAs) were found to be critical modulators in the CRC progression. The aim of this study is to investigate the potential roles of lncRNA P73 antisense RNA 1T (TP73-AS1) in CRC development and progression. METHODS: Quantitative real-time PCR (qRT-PCR) was performed to determine relevant gene expression levels; western blot was performed to determine protein expression levels; CCK-8, colony formation, wound healing and Transwell invasion assays were used to determined CRC cell proliferation, migration and invasion; in vivo tumor growth was assessed in xenograft mice model. RESULTS: TP73-AS1 was up-regulated in both CRC tissues and CRC cell lines. Overexpression of TP73-AS1 was associated with metastasis and advanced clinical stages in CRC patients. Overexpression of TP73-AS1 promoted CRC cell growth, proliferation, migration and invasion in vitro; and knockdown of TP73-AS1 significantly inhibited CRC cell growth, proliferation, migration and invasion in vitro as well as tumor growth in vivo. Bioinformatics analysis and luciferase reporter assay indicated that TP73-AS1 could bind directly with miR-194, and TP73-AS1 negatively regulated the expression of miR-194 in CRC cells. Further study indicated that miR-194 negatively regulated the downstream target of transforming growth factor alpha (TGFα) via targeting its 3’ untranslated region, and TP73-AS1 positively regulated the expression of TGFα in CRC cells. Moreover, overexpression of miR-194 suppressed CRC cell proliferation and invasion, and attenuated the effects of TP73-AS1 overexpression on CRC cell proliferation and invasion. Silence of TGFα inhibited CRC cell proliferation and invasion, and also reversed the effects of TP73-AS1 overexpression on CRC cell proliferation and invasion. CONCLUSIONS: this study demonstrated that TP73-AS1 regulated CRC progression by acting as a competitive endogenous RNA to sponge miR-194 to modulate the expression of TGFα.
