ANXA1 and neoplasm: Importantly, all the identified antigens, except for FUBP2 and ANXA1, induced a powerful humoral response not only in KPC but also in KC bearing PanIN lesions, indicating that the antibody response to these TAAs is already occurring when Kras is the only genetic alteration in the tumor, independently of p53 mutation, which is a later event in PDAC development.