CTSG and squamous cell lung carcinoma: As shown in Figure S2, we found that CTSG was significantly downregulated in a variety of cancers, such as bladder urothelial carcinoma, breast invasive carcinoma, cervical squamous cell carcinoma and endocervical adenocarcinoma, cholangio carcinoma, colon adenocarcinoma, esophageal carcinoma, HNSC, kidney chromophobe, liver hepatocellular carcinoma, lung adenocarcinoma, lung squamous cell carcinoma, prostate adenocarcinoma, rectum adenocarcinoma, stomach adenocarcinoma, and endometrial carcinoma.