Common bile duct injection as a novel method for establishing red fluorescent protein (RFP)-expressing human pancreatic cancer in nude mice

Context: In our previous pancreatic cancer mouse models, we have used surgical orthotopic implantation of human pancreatic tumors to establish clinically relevant fluorescent mouse models of pancreatic cancer. Objective: Since exocrine pancreatic cancer is thought to arise from the cells lining the ducts of the pancreas, we hypothesized that direct injection of tumor cells into the common bile duct would also result in pancreatic tumor formation and metastasis. Intervention: In this study we injected a suspension of the low passage human pancreatic cancer cell line xPA-1 transfected with red fluorescent protein into the common bile duct of nude mice. Main outcome measure: Pancreatic tumor growth and metastasis formation was monitored by intravital and whole body fluorescent imaging. Single fluorescent pancreatic cancer cells were imaged in the pancreatic duct shortly after injection using the Olympus OV100 Whole Mouse Imaging System. Results: Five days after tumor cell injection in the common bil e duct, tumor colonies could be imaged forming within the pancreatic duct. Metastases in the liver were imaged 14 days post common bile duct injection. By day 28, massive tumors were imaged encompassing the entire pancreas. By day 42, RFP-expressing metastases were imaged in the omentum and liver. Conclusion: Common bile duct injection is a novel technique for the development of fluorescent mouse models of metastatic pancreatic cancer.