title: MiR-9 is involved in TGF-β1-induced lung cancer cell invasion and adhesion by targeting SOX7.
abstract: MicroRNA (miR)-9 plays different roles in different cancer types. Here, we investigated the role of miR-9 in non-small-cell lung cancer (NSCLC) cell invasion and adhesion in vitro and explored whether miR-9 was involved in transforming growth factor-beta 1 (TGF-β1)-induced NSCLC cell invasion and adhesion by targeting SOX7. The expression of miR-9 and SOX7 in human NSCLC tissues and cell lines was examined by reverse transcription-quantitative polymerase chain reaction. Gain-of-function and loss-of-function experiments were performed on A549 and HCC827 cells to investigate the effect of miR-9 and SOX7 on NSCLC cell invasion and adhesion in the presence or absence of TGF-β1. Transwell-Matrigel assay and cell adhesion assay were used to examine cell invasion and adhesion abilities. Luciferase reporter assay was performed to determine whether SOX7 was a direct target of miR-9. We found miR-9 was up-regulated and SOX7 was down-regulated in human NSCLC tissues and cell lines. Moreover, SOX7 expression was negatively correlated with miR-9 expression. miR-9 knockdown or SOX7 overexpression could suppress TGF-β1-induced NSCLC cell invasion and adhesion. miR-9 directly targets the 3' untranslated region of SOX7, and SOX7 protein expression was down-regulated by miR-9. TGF-β1 induced miR-9 expression in NSCLC cells. miR-9 up-regulation led to enhanced NSCLC cell invasion and adhesion; however, these effects could be attenuated by SOX7 overexpression. We concluded that miR-9 expression was negatively correlated with SOX7 expression in human NSCLC. miR-9 was up-regulated by TGF-β1 and contributed to TGF-β1-induced NSCLC cell invasion and adhesion by directly targeting SOX7.
authors.affiliation: Department of Oncology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
authors.forename: Lichun
authors.initials: L
authors.lastname: Han
authors.affiliation: School of Pharmacy, Qingdao University, Qingdao, Shandong, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of General Medicine, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Ding
authors.affiliation: Department of Oncology, The Affiliated Hospital of Qingdao University, Qingdao, Shandong, China.
authors.forename: Lijian
authors.initials: L
authors.lastname: Zhang
mesh_terms: D001483:Base Sequence; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics / Q000473:pathology; D002448:Cell Adhesion / Q000187:drug effects / Q000235:genetics; D045744:Cell Line, Tumor; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D055785:Gene Knockdown Techniques; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000473:pathology; D008297:Male; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D055760:SOXF Transcription Factors / Q000235:genetics* / Q000378:metabolism; D053773:Transforming Growth Factor beta1 / Q000494:pharmacology*
chemical_list: C541874:MIRN92 microRNA, human; D035683:MicroRNAs; C484456:SOX7 protein, human; D055760:SOXF Transcription Factors; D053773:Transforming Growth Factor beta1
keywords: SOX7; adhesion; invasion; lung cancer; microRNA-9; transforming growth factor-beta 1