Experiments with the mouse KPC orthotopic transplantation model of pancreatic cancer positive for Kras and Trp53 mutations revealed a localized cell population around and within blood vessels that manifested epithelial-mesenchymal hybrid characteristics, including a loss of polarity associated with cytoplasmic expression of E-cadherin and EpCAM as well as expression of ID1, CD44v6, and LIN28B. This evidence concerns the gene ID1 and familial pancreatic carcinoma.