Induction of potent antitumour natural-killer cells from peripheral blood of patients with advanced prostate cancer.

Abstract

To examine whether antitumour natural-killer (NK) cells can be induced from peripheral blood mononuclear cells (PBMCs) of patients with advanced prostate cancer, as cell therapy using antitumour immune cells is a promising candidate treatment but such patients generally have a suppressed immune response against cancer cells. PBMCs were obtained from 10 patients (four with stage D2 and six with stage B or C disease). For the NK cell expansion, PBMCs were co-cultured with irradiated HFWT cells, a cell line originating from Wilms' tumour, in RHAM alpha culture medium supplemented with 5% autologous plasma and interleukin-2 (200 U/mL) for 2 weeks. When PBMCs were co-cultured with HFWT cells, lymphocytes from all patients had a 20- to 130-fold expansion after 2 weeks of culture. The CD16+ CD56+ cells constituted >70% of the proliferated lymphocyte population. The induced NK cells had significantly greater cytotoxicity against a prostate cancer cell line (PC-3) than lymphocytes cultured with no HFWT cells. There was no significant difference in growth and phenotypes of lymphocytes and the induced NK cell activity between patients with stage D2, B or C. NK cells with potent cytotoxic activity against prostate cancer cell lines from patients with advanced prostate cancer were selectively expanded. Further investigation is needed to determine whether this approach could be a candidate for cell therapy for advanced prostate cancer.