We also tested pancreatic tumors from genetically engineered mice (Pdx1-Cre; KrasG12D; Ink4a/Arfflox/flox and Pdx-1-Cre; LSL-KrasGD12; LSL-Trp53R172H) developing PDAC, which showed no reactivity to mAbJ28 (unpublished data). This evidence concerns the gene PDX1 and pancreatic neoplasm.