PRAME and melanoma: Following previous findings demonstrating PRAME as a negative regulator of RA signaling by forming a ternary complex with EZH2 and RARα in melanoma cells [18], we employed proximity ligation assay (PLA) to study PRAME-EZH2 and PRAME-RARα interactions in SYO-1 and MoJo cells and found that PRAME physically interacts with EZH2 and RARα as shown by the green PLA signals (Figs. 4A, B and S4A, B).