Immune cell functions in pancreatic cancer

Pancreatic cancer kills nearly 29,000 people in the United States annually- as many people as are diagnosed with the disease. Chemotherapeutic treatmen t is ineffective in halting progression of the disease. Yet, specific immun ity to pancreatic tumor cells in subjects with pancreatic cancer has been d emonstrated repeatedly during the last 24 years. Attempts to expand and enh ance tumor-specific immunity with biotherapy, however, have not met with su ccess. The question remains, "Why can't specific immunity regulate pancreat ic cancer growth?" The idea that tumor cells have evolved protective mechan isms against immunity was raised years ago and has recently been revisited by a number of research laboratories. In pancreatic cancer, soluble factors produced by and for the protection of the tumor environment have been dete cted and are often distributed to the victim's circulatory system where the y may effect a more generalized immunosuppression. Yet the nature of these soluble factors remains controversial, since some also serve as tumor antig ens that are recognized by the same T cells that may become inactivated by them. Unless the problem of tumor-derived immunosuppressive products is add ressed directly through basic and translational research studies, successfu l biotherapeutic treatment for pancreatic cancer may not be forthcoming.