miRNA-29c suppresses lung cancer cell adhesion to extracellular matrix and metastasis by targeting integrin β1 and matrix metalloproteinase2 (MMP2).
Our pilot study using miRNA arrays found that miRNA-29c (miR-29c) is differentially expressed in the paired low-metastatic lung cancer cell line 95C compared to the high-metastatic lung cancer cell line 95D. Bioinformatics analysis shows that integrin β1 and matrix metalloproteinase 2 (MMP2) could be important target genes of miR-29c. Therefore, we hypothesized that miR-29c suppresses lung cancer cell adhesion to extracellular matrix (ECM) and metastasis by targeting integrin β1 and MMP2. The gain-of-function studies that raised miR-29c expression in 95D cells by using its mimics showed reductions in cell proliferation, adhesion to ECM, invasion and migration. In contrasts, loss-of-function studies that reduced miR-29c by using its inhibitor in 95C cells promoted proliferation, adhesion to ECM, invasion and migration. Furthermore, the dual-luciferase reporter assay demonstrated that miR-29c inhibited the expression of the luciferase gene containing the 3'-UTRs of integrin β1 and MMP2 mRNA. Western blotting indicated that miR-29c downregulated the expression of integrin β1 and MMP2 at the protein level. Gelatin zymography analysis further confirmed that miR-29c decreased MMP2 enzyme activity. Nude mice with xenograft models of lung cancer cells confirmed that miR-29c inhibited lung cancer metastasis in vivo, including bone and liver metastasis. Taken together, our results demonstrate that miR-29c serves as a tumor metastasis suppressor, which suppresses lung cancer cell adhesion to ECM and metastasis by directly inhibiting integrin β1 and MMP2 expression and by further reducing MMP2 enzyme activity. The results show that miR-29c may be a novel therapeutic candidate target to slow lung cancer metastasis.
The Central Laboratory, Shanghai Pulmonary Hospital, Tongji University School of Medicine, Shanghai, China.
Heyong
H
Wang
Yingchao
Y
Zhu
Mingchuan
M
Zhao
Chunlian
C
Wu
Peng
P
Zhang
Liang
L
Tang
Huijun
H
Zhang
Xiaofeng
X
Chen
Yaoqin
Y
Yang
Gentao
G
Liu
D020413:3' Untranslated Regions / Q000235:genetics; D000818:Animals; D001483:Base Sequence; D002417:Cattle; D002448:Cell Adhesion / Q000235:genetics; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D015536:Down-Regulation / Q000235:genetics; D005109:Extracellular Matrix / Q000473:pathology*; D005260:Female; D019012:Integrin beta1 / Q000235:genetics*; D008175:Lung Neoplasms / Q000235:genetics / Q000473:pathology*; D020781:Matrix Metalloproteinase 1 / Q000235:genetics*; D051379:Mice; D008819:Mice, Nude; D035683:MicroRNAs / Q000235:genetics*; D009361:Neoplasm Invasiveness; D009362:Neoplasm Metastasis; D051381:Rats
D020413:3' Untranslated Regions; D019012:Integrin beta1; C532045:MIRN29a microRNA, human; D035683:MicroRNAs; D020781:Matrix Metalloproteinase 1