SPN and B-cell non-Hodgkin lymphoma: As a result of such early activation, most MYC-transgenic models develop pre-GC derived B-cell lymphomas that, while reproducing some histo-morphologic features of the human disease, lack surface IG expression (EμMYC mouse model) (74, 78) or retain transitional B cell markers (e.g. CD43) in the absence of somatically mutated IGHV regions (λ-MYC mouse model and 3’ IgH LCR-driven Myc transgenics) (75, 77), an indication that the malignant transformation process occurred in transitional/pre-GC cells.