Low Dose Vaccine Study for Surgically Resected Pancreatic Cancer

Unfortunately, despite the best clinical efforts and breakthroughs in biotechnology, most patients diagnosed with pancreatic cancer continue to die from their disease in a very short period of time. The primary reason for this is the short progression time of the disease; in fact, most patients with pancreatic cancer have symptoms at the time of the diagnosis. Moreover, lack of any single agent or procedure to have any significant impact on long term survival rates further contributes to poor prognostic outcomes observed with this disease. These reasons are the major causes of cancer progression that are usually discussed when considering treatment options for patients with disease that continues to grow and spread. However, another important part of the body should be considered-- the immune system. Scientists have clearly shown that pancreatic cancer cells as well as other cancer cells produce a number of abnormal proteins or abnormal amounts of certain proteins not found in normal cells. Normally one would expect a patient to develop an immune response against these abnormal proteins found in their cancer and attack them much the way we would fight off an infection from a foreign bacteria or virus. However, for reasons that scientists do not fully understand, the immune system fails to respond to these abnormal proteins and does not attack the cancer cells. This human clinical trial proposes a new way to make the immune system recognize the cancer and encourage it to attack the cancer cells. Many people are familiar with the idea of transplants between people of organs like the kidneys or heart. When an organ transplant between two people is completed one of the problems that can occur is rejection of the donated organ by the recipient. This can occur because the immune system of the patient who receives the organ attacks the donated organ. If you were to attempt to transplant a pig heart to a human the rejection would be dramatically stronger than when organs are transplanted between two people. This is partly because lower animals express sugar-protein patterns on the surface of their cells that humans do not. In fact, our immune systems can quickly recognize tissues from lower mammals such as the pig or the mouse and destroys them. In this project, we propose to put a mouse gene into human pancreatic cancer cells that produces these abnormal sugar patterns and stimulates the immune system to attack the pancreatic cancer. This strategy works well to kill other human cancer cells in the laboratory, but it needs to be tried in pancreatic cancer patients to see if it will be effective. We propose to test this new treatment in patients with pancreatic cancer who have undergone tumor resection to see if it can stop or slow recurrence of tumors in these patients. Patients will be injected with an anti-tumor vaccine consisting of a mixture of two types of dead human pancreatic cancer cells that have been genetically altered to express the mouse gene responsible for making this abnormal sugar-protein on the cells.