pBabe-GFP empty vector or pBabe-GFP- MYC vector63, pMX-T7-2xFlag empty vector or pMX-T7-2xFlag-Menin vector (gift from Dr Xianxin Hua in University of Pennsylvania)64 was co-transfected with plasmids encoding gag/pol and VSVG into HEK293T packaging cells using lipofectamine 2000 (...