It is evident that single miRNAs may regulate translation of numerous downstream mRNAs and each mRNA is likely to be regulated by several miRNAs simultaneously [30, 32] . Thus, identification of miRNA target genes has been a great challenge [33] . Numerous computational algorithms [34] [35] [36] [37] [38] [39] [40] [41] [42] [43] were established which combined 5' seed matches, thermodynamic stability and conservation analysis in order to maximize specificity when predicting mRNA targets [44] (Table 1) . Nevertheless, various algorithms differ in the selection of mRNA targets and simultaneous application of several algorithms is, therefore, highly recommended. Nowadays, many web-based applications [45] [46] [47] [48] [49] [50] [51] [52] have been developed by combining existing prediction programs with functional annotations associated to many miRNA, gene, protein or biological pathway resources such as miR-Base, Ensembl, Swiss-Prot, UCSC genome browser, KEGG pathway and other databases [44] (Table 2) .