PDCD1 and lung cancer: Ultimately, calnexin (CANX), an endoplasmic reticulum lectin chaperone protein (Ellgaard et al., 2016; Kozlov and Gehring, 2020), has been confirmed to be upregulated in tumors including lung cancer and oral squamous carcinomas, and its ability to inhibit the proliferation of CD4+ T and CD8+ T cells in tumor tissues (Kobayashi et al., 2015; Alam et al., 2019; Chen et al., 2019), as well as the release of cytokines (PD-1, IFN-γ, and TNF), which eventually promotes tumor growth.