Selective effect of cytokine-induced killer cells on survival of patients with early-stage melanoma.

Adoptive immunotherapy using cytokine-induced killer (CIK) cells has shown potential antitumor ability against several kinds of cancers, including melanoma. However, little is known about the achievable outcome of CIK cells in melanoma patients at different pathological stages. Here we recruited 55 patients treated with conventional therapy plus CIK cells as the CIK group, and 49 patients treated with conventional therapy alone as the control group. The pathological characteristics were comparable between two groups, with a follow-up period up to 40 months. Survival data and immune responses were evaluated after CIK cell treatment. In this study, CIK cells were successfully generated from peripheral blood of melanoma patients after in vitro culture for 14 days. The cultured CIK cells not only produced high levels of pro-inflammatory cytokines upon in vitro stimulation but also efficiently killed human melanoma cell lines. No serious side events were observed in all patients treated with CIK cells. Furthermore, infusions of CIK cells improved the quality of life in some patients, including advanced cases. More importantly, the CIK group exhibited better survival rates compared to the control group among early-stage melanoma patients, in consistent with the increased frequency of peripheral CD4 T cells. However, the patients with advanced-stage melanoma did not benefit from the CIK cell therapy in terms of survival rate. In conclusion, CIK cells combined with conventional treatments may prolong the survival of early-stage melanoma patients and improve the quality of life for some advanced cases in a safe way.