Inflammation and colorectal cancer: does aspirin affect the interaction between cancer and immune cells?

The effect of aspirin on colon-cancer-cell-induced cytokine secretion by peripheral blood mononuclear cells (PBMC) was examined. Aspirin was added to human colon cancer cells (HT-29 and RKO) or to PBMC incubated separately or jointly. The secretion of IFNγ, IL-6, and IL-10 induced by HT-29 cells was decreased, that of IL-1β was slightly increased, whereas IL-1ra production was not affected. With RKO cells, aspirin reduced IL-6, IL-1ra, and IL-10 synthesis and enhanced IFNγ secretion, while IL-1β remained unchanged. Conditioned media from colon cancer cells incubated without or with aspirin stimulated cytokine productions by PBMC similarly, suggesting that aspirin acts on the cell-to-cell interaction between cancer cells and PBMC. The results indicate that aspirin alter the balance between pro- and anti-inflammatory cytokines generated by interaction between colon cancer and immune cells disclosing an additional role of the drug in affecting inflammation-induced colon cancer.