Effects of anticancer agents on cell viability, proliferative activity and cytokine production of peripheral blood mononuclear cells

We investigated the effects of anticancer agents on peripheral blood mononuclear cells for the purpose of providing data to support new translational chemoimmunotherapy regimens. Peripheral-blood mononuclear cells were treated with one of four anticancer agents (5-fluorouracil, irinotecan, cisplatin, and gemcitabine) for 2 h, after which cell viability was determined. For assessment of effects of each drug on proliferation and cytokine production, cells were stimulated with phytohemagglutinin for 48 h. As a result, the anticancer agents did not affect cell viability. Cell proliferation was unaffected by 5-fluorouracil and irinotecan but inhibited by cisplatin and gemcitabine. Treatment with gemcitabine enhanced the production of IFN-γ and decreased the number of regulatory T cells. gemcitabine treatment increased IFN-γ production among CD4 T cells but not among CD8 T cells. The results indicated that GEM had immunoregulatory properties that might support immune response against cancer. This finding has implications for designing chemoimmunotherapy strategies.