As was displayed in the boxed plots (Figures 12A–C), mRNA expression levels of PAPSS2, ITPKA, and CYP1A1 had the most statistically significant differences (p < 0.001) in multiple normal and cancer tissues, such as invasive breast carcinoma (BRCA), kidney renal clear cell carcinoma (KIRC), liver hepatocellular carcinoma (LIHC), lung adenocarcinoma (LUAD), lung squamous cell carcinoma (LUSC), and thyroid carcinoma (THCA). Here, PAPSS2 is linked to squamous cell lung carcinoma.