It belongs to the SLC7-APC (amino acid-polyamine-organocation) superfamily (Scalise et al., 2018), participates in the immunosuppressive lung tumor microenvironment, and is associated with a low response to immunotherapy (Liu et al., 2022), high cancer stem cell (CSC) activity, and shorter overall survival (Liu et al., 2021c). The gene discussed is APC; the disease is cancer.