Aims at annotating the experimentally verified oncogenic and tumor-suppressive miRNAs from literature. OncomiRDB only collects items having direct functional evidences: 1) the miRNA regulates at least one cancer-related phenotype or cellular process (such as proliferation, apoptosis, migration and invasion, senescence and cell cycle regulation); or 2) the miRNA directly regulates at least one oncogenic or tumor-suppressive gene verified by luciferase reporter assay.