CTSL and cancer: Supplementary Figure S4 also showed the correlation of the CTSL expression and immune infiltration levels in multiple cancer types. The expressions of CTSL in thyroid and endometrial cancers were related to at least two types of infiltrating immune cells. In digestive, urogenital, and respiratory cancers, only COAD, STAD, LUAD, and LUSC showed a correlation between CTSL and at least two types of infiltrating immune cells (Figures 8A–N).