ITGA3 and keratoacanthoma: By the end of the treatment (P196), ulcerating tumors were observed in one K19 Itga3 KO and three WT mice, which were identified as SCCs (K19 Itga3 KO and WT) and keratoacanthomas with carcinomatous changes (K19 Itga3 WT) by histological analysis (Fig S3B).