Therapeutic effect on the subcutaneous 4T1 tumor model
(A) Schematic representation of the therapeutic timeline of siAdar1-LNP@mPD1 on the subcutaneous 4T1 tumor model. (B) In vivo fluorescence imaging of the 4T1 tumor-bearing mouse at different time points after intravenous (i.v.) injection of siAdar1-LNP@mPD1, siAdar1-LNP@m, or free siAdar1. (C) Ex vivo fluorescence imaging of excised major organs and tumors from the mice after 24 h i.v. injection of different formulation. (D) Analysis of the mean fluorescence intensity (MFI) of major organs and tumors by ImageJ software. (E) Average and individual tumor growth kinetics of mice after i.v. injection with PBS, siAdar1-LNP@m, siNC-LNP@mPD1, or siAdar1-LNP@mPD1 (mean ± SD; n = 10; ∗∗p < 0.01, ∗∗∗∗p < 0.0001). (F and G) Photographs (F) and weights (G) of tumors excised from all treated mice on day 20 (mean ± SD; n = 10; ∗∗p < 0.01, ∗∗∗∗p < 0.0001). (H) H&E, Ki67, and TUNEL staining of tumor slices after different treatments. Scale bars, 100 μm. (I–K) The qRT-PCR analysis of the relative expression of ADAR1 mRNA (I), WB analysis (J), and the relative expression (K) of ADAR1 protein from excised 4T1 tumor cells after different treatments (mean ± SD; ∗∗∗∗p < 0.0001; n = 3).