Cytokine-induced killer cells in the treatment of patients with solid carcinomas: a systematic review and pooled analysis

Background aimsThe aim of this study was to evaluate the efficacy and safety of cytokine-induced killer (CIK) cell therapy for solid carcinomas.MethodsWe performed a computerized search of phase II/III clinical trial databases of CIK cell-based therapy using a combination of the terms ‘cytokine-induced killer cells’, ‘tumor’ and ‘cancer’.ResultsTreatment with CIK cells was associated with a significantly improved half-year survival (P = 0.003), 1-year survival (P = 0.0005), 2-year survival (P  < 0.01) and mean survival time (MST) (P  < 0.001). Patients in the CIK group showed a prolonged half-year progression-free survival (PFS) (P  < 0.01), 1-year PFS (P < 0.01) and median time to progression (MTTP) (P < 0.001). A favored disease control rate (DCR) was observed in patients receiving CIK cell therapy, while the objective response rate (ORR) was not altered (P = 0.05) compared with the non-CIK group (P = 0.007). CIK cell therapy could also reduce the adverse effects of grade III and IV leukopenia caused by chemotherapy (P = 0.002) and diminish hepatitis B virus (HBV)-DNA content (P < 0.01). However, the incidence of fever in the CIK therapy group was significantly higher than in the non-CIK group (P = 0.02). The percentage of CD3⁺, CD4⁺, CD4⁺ CD8⁺, CD3^? CD56⁺ and CD3⁺ CD56⁺ T-lymphocyte subsets in the peripheral blood of cancer patients was significantly increased, whereas the percentage of CD8⁺ T-lymphocyte cells was significantly decreased in the CIK group compared with the non-CIK group (P < 0.01).ConclusionsCIK cell therapy has demonstrated a significant superiority in prolonging the MST, PFS, DCR and quality of life (QoL) of patients.