Proteomic and western blot validation of ORFs encoding immunogenic neojunction-derived neoantigens in NPC. (A) Mass spectrometry provided protein-level evidence supporting the existence of neojunction-derived neoantigens. (B) Western blot analysis showing the expression of FLAG-tagged ORFs encoding the validated immunogenic neojunction-derived neoantigens in HEK293T and NP69 cells after transfection.