IL-8, IL-1A, and TRAIL play key roles in the potentiated bystander killing effect. (A) Expression ratio of 112 cytokines relative to the control group was shown in HCT 116 cells infected with M1 (MOI = 1 pfu/cell) for 24 h. (B) Detailed information on the top 10 cytokines in A (red dots). (C) HCT 116 cells were treated with LCL161 or LCL161 plus different concentrations of recombinant proteins of IL-8, IL-1A, and TRAIL for 72 h, and cell viability was detected. HCT 116 cells were treated with M1 for different lengths of time, and mRNA level (D) and protein level (E) of IL-8, IL-1A, and TRAIL were detected with RT-quantitative PCR and ELISA. Error bars represent mean ± SD obtained from three independent experiments. *P < 0.05; **P < 0.01; ***P < 0.001.