IDO1 and neoplasm: Using an immunosuppressive microenvironment to alleviate intractable tumor microenvironments, Wang et al. developed a novel mesoporous nanocarrier with a core made of upconverting nanoparticles and a shell made of large pores of mesoporous silica (UCMS) simultaneously loaded with photosensitizer molecules, the AL-9 peptide vaccine from the IDO, and the inhibitors of PD-L1, and tested it in Lewis murine lung carcinoma cell line and mouse model.