LIN28A and neoplasm: While the microRNA let-7 is a well-established tumor suppressor, the oncogenic role of Lin28 is best characterized as a let-7 inhibitor; Lin28 binds to let-7 microRNA precursors and further recruits the terminal uridylyl-transferases (TUTs) to initiate polyuridylation modification of pre-let-7 and subsequently pre-let-7 degradation [8].