title: MicroRNA-561 inhibits gastric cancercell proliferation and invasion by downregulating c-Myc expression.
abstract: Gastric cancer (GC) causes nearly one million deaths worldwide each year. However, the molecular pathway of GC development remains unclear. Increasing evidences have shown that microRNAs (miRNAs) are highly associated with tumor development. However, relative little is known about the potential role of miRNAs in gastric cancer development. In the present study, we showed that miR-561 was down-regulated frequently in human GCs cell lines and tissues, and its expression was associated with tumor-node-metastasis (pTNM) stage. Enforced expression of miR-561 in GC cells inhibited cell proliferation and invasion in vitro. In contrast, knockdown of miR-561 had the opposite effect on cell proliferation and invasion. Moreover, c-Myc was identified as a potential miR-561 target. Further studies confirmed that miR-561 suppressed the expression of c-Myc by directly binding to its 3'-untranslated region. Restoration of c-Myc in miR-561-overexpressed GC cells reversed the suppressive effects of miR-561 and c-Myc was inversely correlated with miR-561 expression in GC tissues. These results demonstrate that miR-561 acts as a novel tumor suppressor in GC by targeting c-Myc gene and inhibiting GC cells proliferation and invasion. These findings contribute to current understanding of the functions of miR-561 in GC.
authors.affiliation: Department of Gastrointestinal Surgery, The First Affiliated Hospital of Chongqing Medical University Chongqing 400016, China.
authors.forename: Kun
authors.initials: K
authors.lastname: Qian
authors.affiliation: The Medical Examination Center, The First Affiliated Hospital of Chongqing Medical University Chongqing 400016, China.
authors.forename: Binglang
authors.initials: B
authors.lastname: Mao
authors.affiliation: Department of Gastrointestinal Surgery, The First Affiliated Hospital of Chongqing Medical University Chongqing 400016, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
authors.affiliation: Department of Cardiothoracic Surgery, The First Affiliated Hospital of Chongqing Medical University Chongqing 400016, China.
authors.forename: Huanwen
authors.initials: H
authors.lastname: Chen
keywords: Gastric cancer; c-Myc; microRNA-561; tumor suppressor