MUC4 and pachyonychia congenita: For example, miR-27a influences the growth and motility of PC cells via targeting Sprouty2 [8]; miR-548an, transcriptionally silenced by HIF1α/HDAC1, inhibits PC tumorigenesis by down-regulating Vimentin expression [9]; miR-219-1-3p negatively regulating mucin MUC4 expression exerts a tumor-suppressive role in PC [10].