4T1-Luc tumor-bearing mice treated with different samples (PBS, DOX@MSNs, and DOX@MSNs-CAIX) for 11 days. The tumors’ bioluminescence imaging before (A) and after (B) intervention with the above samples. (C) The tumors’ bioluminescence intensity before (the 0th day) and after (the 11th day) intervention with the above samples. (D) The tumors’ photographs from the scarified mice. (E) The final average tumor weight. (F) The variation curves of average tumor volume. (* p < 0.05 as compared with PBS group.) Source: reprinted from Chen, M.; Hu, J.; Wang, L.; Li, Y.; Zhu, C.; Chen, C.; Shi, M.; Ju, Z.; Cao, X.; Zhang, Z., Targeted and redox-responsive drug delivery systems based on carbonic anhydrase IX-decorated mesoporous silica nanoparticles for cancer therapy. Scientific Reports 2020, 10, (1), 14447 [112] under an open access Creative Commons CC BY 4.0 license.