DSR 6434 is an agonist of toll-like receptor 7 (TLR7).1 It induces reporter gene activity in HEK293 cells expressing human TLR7 (EC50 = 7.9 nM) but not HEK293 cells expressing human TLR8 or TLR9. DSR 6434 (0.64-2,000 nM) induces production of chemokine (C-X-C motif) ligand 10 (CXCL10), IL-12p70, IFN-γ, and TNF-α in splenocytes isolated from Tlr7 wild-type, but not Tlr7-/-, mice. In vivo, DSR 6434 (0.1 mg/kg) reduces tumor volume and increases survival, as well as potentiates the antitumor effects of ionizing radiation, in a CT26 murine colon cancer model. It also potentiates the antitumor effects of ionizing radiation and decreases the number of metastases in a KHT murine fibrosarcoma model.
1.Adlard, A.L., Dovedi, S.J., Telfer, B.A., et al.A novel systemically administered Toll-like receptor 7 agonist potentiates the effect of ionizing radiation in murine solid tumor modelsInt. J. Cancer135(4)820-829(2014)