CD274 and cancer: In recent years, the application of CRISPR-based functional genomics screens has significantly advanced our understanding of the molecular regulators of PD-L1 and MHC-I (HLA-I for human) in cancer cells, providing key insights into the molecular landscape of tumor immune surveillance.7–11 However, these traditional CRISPR/Cas9 screens are limited in their resolution and provide information primarily at the gene level, which can be insufficient for understanding the functional impacts of specific mutations or genetic variations.