The miR-23a/27a/24 - 2 cluster drives immune evasion and resistance to PD-1/PD-L1 blockade in non-small cell lung cancer.

Programmed cell death protein ligand-1 (PD-L1) and major histocompatibility complex I (MHC-I) are key molecules related to tumor immune evasion and resistance to programmed cell death protein 1 (PD-1)/PD-L1 blockade. Here, we demonstrated that the upregulation of all miRNAs in the miR-23a/27a/24 - 2 cluster was correlated with poor survival, immune evasion and PD-1/PD-L1 blockade resistance in patients with non-small cell lung cancer (NSCLC). The overexpression of all miRNAs in the miR-23a/27a/24 - 2 cluster upregulated PD-L1 expression by targeting Cbl proto-oncogene B (CBLB) and downregulated MHC-I expression by increasing the level of eukaryotic initiation factor 3B (eIF3B) via the targeting of microphthalmia-associated transcription factor (MITF).