Duan et al. indicated that the Drosha processing can be hindered by a single nucleotide polymorphism emerging in the stem of pri-miRNAs [11], whereas by studying the tumor-associated mutation, Diederichs et al. found that the Drosha processing remains intact even if the secondary structure of pri-miRNA is altered by many sequence variations found in human cancers [12]. This evidence concerns the gene DROSHA and cancer.