In our data, Cathepsin L1 (CTSL) exhibited a 1.555-fold increase exclusively in COVID-19 lungs, which is consistent with Nie's data [3], but this is not shown in the human colon epithelial carcinoma cell line Caco-2 after SARS-CoV-2 infection [5]. The gene discussed is CTSL; the disease is digestive system cancer.