To assess the immunological response of human tumor tissues to ex vivo PD-1 blockade, several reports have used various systems, including air-liquid-interface organoids (Neal et al., 2018), microfluidic devices with organotypic tumor spheroids (Jenkins et al., 2018) and patient-derived tumor fragment platforms (Voabil et al., 2021). This evidence concerns the gene PDCD1 and neoplasm.