Cytokine expression in colon carcinoma.

Background: Cytokines reflect the activity of the immune system. We analyzed the local expression of characteristic cytokines indicating the level of activity of unspecific inflammatory cells, Th1-cells and Th2-cells in colon cancer.

Materials And Methods: In 25 tumor/ mucosa pairs, IL-1alpha, IL-2, IL-4, IL-5, IL-15, TNF-alpha and IFN-gamma were measured by real-time PCR.

Results: There was a significant increase in IL-1alpha, IL-4, IL-5 and TNF-alpha and a significant decrease in IL-2 in tumor tissue compared to normal mucosa.

Discussion: The cytokine profile in colon cancer indicates a strong unspecific inflammatory reaction in the tumor tissue represented by high levels of IL-1 and TNF-alpha. The comparatively low level of IL-2 suggests suppression of a specific immunological reaction, namely Th1-cells. It can be hypothesized that this is a result and/or cause of local immune escape mechanisms. Furthermore, there is an activation of TH2 cells in the carcinomas.