The absence of LTB4/BLT1 signaling induces potent antitumor effects against the second tumor challenge of WEHI3B cells after marked regression of WGM cells in mice model. (A) WEHI3B and WGM cells were cultured separately at 1 × 104 cells/well for 2, 4, 6, and 8 days in CM. At each time point, the number of viable cells was determined by trypan blue dye exclusion assay. (B) The explanatory scheme for all of the following in vivo experiments. The early phase, intermediate phase, and late phase in tumorigenicity assay are defined as spanning from days 0-4, 5-20, and 21-50 after the FTC, respectively. (C) In vivo tumorigenicity assay. The FTC consisted of 5 × 105 WEHI3B or WGM cells subcutaneously inoculated into the right flank of WT or BLT1-KO mice (n = 6–8). (D-E) In vivo STC assay. On day 50 after the FTC, 5 × 105 WEHI3B cells were subcutaneously inoculated into the left flank of mice that completely rejected the challenged tumor cells. The tumor volumes (mm3) in 4 indicated mice groups were assessed on day 17. Kaplan-Meier survival curves are shown after the STC. Bars represent mean ± SEM. Significant difference: *P < .05, **P < .01. Representative data from 2-6 independent experiments with similar results are shown.
