PTPN2 and neoplasm: Yang et al. [154] designed a programmable unlocking nano-matryoshka-CRISPR system (PUN@Cas-PT) that targeted PD-L1 (an immunosuppressive marker in tumor cells) and protein tyrosine phosphatase N2 (PTPN2, a negative regulator rendering tumor resistant to immunotherapy) (Fig. 9A).