PTPA and melanoma: miR-218 is a tumor suppressive miRNA decreased in A375 melanoma stem-like cells, while the transfection of these cells with this miRNA mimic has been shown to cause cell cycle arrest in the G0/G1 phase, by targeting cellular inhibitor of PP2A (CIP2A) and BMI-1, supporting the hypothesis of the pivotal role of miR-218 in melanoma development [102,144].