PAX8 and neoplasm with perivascular epithelioid cell differentiation: Treatment of HK2/SFPQ-TFE3 cells with the mTOR kinase inhibitor Torin1 rescued PAX2 and PAX8 protein expression in a dose-dependent fashion and simultaneously downregulated expression of the PEComa marker PMEL, as well as multiple MiT/TFE-regulated proteins (LC3A/B, RRAGD, RAB7A, and GPNMB), by immunoblotting (Fig. 7A, B, Supplementary Fig. 9A, B).