The up-regulation of pro-apoptotic signalling systems in peripheral blood lymphocytes of malnourished patients with pancreatic cancer after preoperative enteral immune-enhancing diet (immunonutrition)

Introduction: Pancreatic cancer surgery is one of the most invasive operations in upper abdominal surgery, witha high incidence of postoperative complications. Extensive tissue trauma and malnutrition results in disorders of programmed cell death influencing the patient's susceptibility to infections. The attempt to correct the postoperative immune disorders by introducing preoperative or postoperative immunonutrition is a promising way of improving outcome after pancreatic surgery. Aim: To investigate the influence of surgical trauma and immunonutrition on the changes of apoptotic signalling pathways, randomized studies were performed in patients after pancreatic cancer surgery receiving preoperative standard or central immunonutrition. Material and methods: The expression of TNFRI/CD120a, Fas/CD95 and Bcl-2 in lymphocytes was assessed by flow cytometry before and on day 1, 3 and 7 after surgery. The percentage of Fas (CD95+CD3-) and TNFRI (CD120a) positive lymphocytes in the whole group of pancreatic cancer patients was significantly higher before as well as after surgery. The percentage of Bcl-2-positive lymphocytes was significantly decreased on day 1 and 7 after surgery. In comparison to standard nutrition, preoperative immunonutrition significantly increased the percentage of CD95 and TNFRI positive lymphocytes after surgery. Results: Our studies revealed the up-regulation of pro-apoptotic signalling systems in peripheral blood lymphocytes of malnourished patients with pancreatic cancer. These pathological alterations in expression of apoptotic signalling pathway proteins may increase lymphocyte dysfunction and immune system suppression, especially after pancreatic resection. Preoperative enteral immunonutrition has a modulatory effect on apoptotic signalling pathways.