CDKN2A and neoplasm: Later, using a CRE-LoxP system by direct injection of Adenovirus expressing Cre recombinase (Adeno-Cre) into the pleural cavity of adult mice, Jongsma et al. developed compound mouse models carrying the combinations of conditional knockout alleles for NF2 and INK4A and/or TP53 that developed tumors with varying tumor latency, aggressiveness, and survival rates.