Fig. 6
Antitumor effect of NK cells against BCa in a subcutaneous tumor model in vivo. (A) Tumor volumes at various times (horizontal axis) after tumor implantation in the control and treatment groups, including NK (E/T = 0.25:1), NK (E/T = 1:1), and NK (E/T = 10:1) groups. Tumor volumes were calculated according to the formula L×W2/2, where L and W represent the longest and shortest diameters measured using a caliper, respectively (n = 6 per group); (B) Body weights in the control and treatment groups over the whole treatment course (n = 6 per group); (C) Images of tumors in mice 28 days after tumor implantation (n = 6 in each group); (D) Tumor weights corresponding to each group when harvested on day 28 (n = 6 in each group); (E) HE examination of tumor specimen in the control and treatment groups on day 28 (n = 6 or 4 for each group); (F) Cumulative Kaplan–Meier survival curves for mice (n = 6 per group) after tumor implantation; (G) Serum IL-6 levels in the control and NK cell treatment groups on day 28 (n = 3, each). Data expressed as mean ± SD were plotted, and ANOVA followed by a Tukey’s post hoc test was used for multiple group comparisons (A, B, C, D and G). The Kaplan–Meier method was used to estimate survival functions. The log-rank test was used for group comparisons (F). *p < 0.05; ns, not significant. Abbreviations: BCa: bladder cancer; E/T: effector-to-target ratio; HE: hematoxylin-and-eosin; IL-6: interleukin-6