Manipulation of NK-cell cytotoxicity by miR-27a* in human tumor xenograft model. (A-C) Tumor growth changes in nude mice bearing human tumor xenografts after treatment of modified mNK cells. (A) At the end of experiment (day 20), tumors were removed and photographed. Scale bar represents 1 cm. Tumor volume changes were measured until day 20 (days 0, 8, 11, 14, 16, 18, and 20). (B) Downward arrows indicate that mice were treated with mNK cells at that time point (days 0 and 7). (C) Scatter plots showing tumor volume of individual mice at day 20. Horizontal lines indicate average of tumor volume of each mouse (n = 8). (D) Time course of inhibition rate (vs PBS-treated group) of tumor volume by treatment with manipulated mNK cells. Tumor volumes were measured using a caliper and estimated by the formula: length (mm) × width (mm) × height (mm)/2. The tumor growth inhibition rate was calculated using the following equation: % inhibition = 100% − (tumor volume of test group/tumor volume of PBS group) × 100% (Mann-Whitney rank sum test, ns, P > .05, *P < .05, **P < .01, and ***P < .001 vs vehicle PBS or Ctrl-miR).