MAF1 and nasopharyngeal carcinoma: Interestingly, a small fraction of MAF1 remained partially phosphorylated when hiPSC were treated with the mTORC1 inhibitor rapamycin and MAF1 from NPC exhibited a similar pattern (Fig. 6b), indicating that phosphorylation at one or more sites in MAF1 (S60, S68 and S75)72 may be less sensitive to this drug.