Purpose: To investigate the specific effect and underlying mechanism of microRNA-26a-5p (miR-26a) in cutaneous squamous cell carcinoma (CSCC).
Methods: miR-26a and MMP14/16 mRNA expression were detected by qRT-PCR analysis. Functional experiments were used to detect the role of miR-26a on CSCC progression. Western blot was used for protein detection. Luciferase assay was used to detect miR-26a directly targeting MMP14 and MMP16. Xenograft nude mice model was used to determine the effect of miR-26a on tumorigenesis.
Results: miR-26a was decreased in CSCC tissues and cells. Forced miR-26a suppressed the progression of SCL-1 and A431 cells. Furthermore, miR-26a directly targeted MMP14 and MMP16 to inhibit their expression. Forced expression of MMP14 and MMP16 removed the miR-26a’s inhibitory effect on CSCC development. The in vivo tumor growth assay showed that miR-26a suppressed CSCC tumorigenesis by targeting MMP14 and MMP16.
Conclusion: Our study suggested miR-26a inhibits cancer cell proliferation, migration and invasion in CSCC by targeting MMP14 and MMP16. 
Keywords: miR-26a, cutaneous squamous cell carcinoma, MMP14, MMP16, tumorigenesis