BRCA1 and familial pancreatic carcinoma: In contrast, when we treated BRCA1-KO fibroblasts with sera of patients with colon or pancreatic cancer, histological analyses of the tumors generated, showed that they were poorly differentiated adenocarcinomas with phenotypical characteristics related to the cancers of the blood donor patients, proving, for the first time, that complete metastatic transformation, through horizontal transfer, is possible [14].