The molecular target of this miRNA is the SMAD-interacting protein [SIP1] gene that is often mutated in PC, which normally inhibits Cadherin E. It was suggested that hypermethylation of the SIP1 promoter may lead to abnormal expression of miR-210, which can be easily detected in serum, thus serving as a surrogate marker [56]. This evidence concerns the gene CDH1 and pachyonychia congenita.