PKNOX1 was highly expressed in 22 tumor tissues, including BRCA, CHOL, LIHC, LUAD, LUSC, STAD, COAD, ACC, and SKCM, which was consistent with the reported results for gastric adenocarcinoma and non-small cell carcinoma (17, 18) and with the results of our immunohistochemical analysis in liver cancer, lung cancer, gastric cancer, and intestinal cancer. Here, PKNOX1 is linked to lung cancer.