Fig. 2: Combination treatment with TLR5 agonist and ICT enhance survival in ICT-refractory tumors and TLR5 host receptors are necessary to elicit the anti-tumor response in a 4T1 tumor model.
From: TLR5 agonists enhance anti-tumor immunity and overcome resistance to immune checkpoint therapy
a Kaplan–Meier survival analysis of BALB/c mice implanted with orthotopic 4T1 FUGW-FL florescent and bioluminescent reporter cells at week 0 and treated with flagellin with or without ICT from week 2 to week 4. Mice treated with vehicle control (PBS) (n = 25), ICT (n = 23), flagellin (n = 22) and flagellin + ICT treatment (n = 22) were compared. Treatment with flagellin + ICT treatment had a statistically significant effect on survival (p = 0.0002, Log-rank test; p = 0.003, Gehan–Breslow-Wilcoxon test) compared to treatment with vehicle control. Treatment with only ICT also showed statistically significant effect on survival (p = 0.01, Log-rank test; p = 0.03, Gehan–Breslow–Wilcoxon test) compared to treatment with vehicle control. However, all ICT-treated mice were dead by week eight. Treatment with only flagellin did not show detectable difference (p = 0.06, Log-rank test; p = 0.08, Gehan–Breslow–Wilcoxon test) compared to treatment with vehicle control. (b) Combination treatment with CBLB502 (low dose) and ICT enhance survival. Kaplan–Meier survival analysis of BALB/c mice implanted with orthotopic 4T1 FUGW-FL florescent and bioluminescent reporter tumor cells at week 0 and treated with CBLB502 (low dose) with or without ICT from week 2 to week 4. Mice treated with vehicle control (PBS) (n = 22), ICT (n = 25), CBLB502 (low dose) (n = 30), and CBLB502 (low dose) + ICT (n = 30) were compared. Treatment CBLB502 (low dose) + ICT had a statistically detectable effect on survival (p = 0.002, Log-rank test; p = 0.001, Gehan-Breslow-Wilcoxon test) compared to treatment with vehicle control. ICT alone treatment did not show a detectable statistical difference by Log-rank test (p = 0.1), but did show a detectable statistical difference with the Gehan–Breslow–Wilcoxon test (p = 0.04). CBLB502 (low dose) alone treatment did not show detectable statistical difference (p = 0.8, Log-rank test; p = 0.3 Gehan–Breslow–Wilcoxon test). c Kaplan–Meier survival analysis of C57BL/6J mice implanted with B16-F10 cells at Day 0 and treated with CBLB502 with or without ICT three days post tumor implantation. Mice treated with vehicle control (PBS) (n = 20), ICT (n = 15), CBLB502 (n = 14) and CBLB502 + ICT treatment (n = 39) were compared. Treatment with CBLB502 + ICT treatment had a statistically significant effect on survival (p = 0.003, Log-rank test; p = 0.01, Gehan–Breslow–Wilcoxon test) compared to treatment with vehicle control. d Kaplan–Meier survival analysis of BALB/c Tlr5+/+ or Tlr5−/− mice implanted with orthotopic 4T1 FUGW-FL florescent and bioluminescent reporter tumor cells at week 0 and treated with vehicle control (PBS) (n = 7, for each vehicle cohort), ICT (n = 2 and n = 4 for Tlr5+/+ and Tlr5-/- mice respectively), CBLB502 (n = 2 and n = 5 for Tlr5+/+ and Tlr5−/− mice respectively), and CBLB502+ICT treatment (n = 10, for each CBLB502 + ICT cohort) were compared. Tlr5+/+ mice treated with CBLB502 (low dose) + ICT had a statistically detectable effect on survival when compared to Tlr5+/+ mice treated with vehicle control (p < 0.001, Log-rank test; p < 0.01, Gehan−Breslow−Wilcoxon test) or Tlr5−/− mice treated with CBLB502 (i.t.) + ICT (p < 0.001, Log-rank test; p < 0.001, Gehan−Breslow−Wilcoxon test). Tlr5+/+ mice treated with vehicle control showed a detectable statistical difference in survival when compared to Tlr5−/− mice treated with vehicle control (p < 0.03, Log-rank test; p < 0.03, Gehan−Breslow−Wilcoxon test).
