The procedure for PCR quantification was previously described (13 (link),18 (link)–20 (link)). The expression levels of miR-375 (assay ID: 000564; Applied Biosystems, Foster City, CA, USA) were analyzed by TaqMan qRT-PCR assays (TaqMan MicroRNA assays; Applied Biosystems) and RNU48 (assay ID: 001006) was used for normalization. TaqMan probes and primers for MMP-13 (assay ID: Hs00233992_m1; Applied Biosystems), CENPF (assay ID: Hs01118845_m1), KIF14 (assay ID: Hs00978236_m1) and GUSB (the internal control; assay ID: Hs00939627_ml; Applied Biosystems) were used for gene expression analysis.