PAQR4 promoter methylation levels in COAD, ESCA, KIRC, KIRP, LUAD, LUSC (lung squamous cell carcinoma), PRAD (prostate adenocarcinoma), BRCA, READ, THCA (thyroid carcinoma), and UCEC were substantially higher compared to those in normal tissues, while the promoter methylation levels in PCPG (pheochromocytoma and paraganglioma) and TGCT were significantly lower than those in normal tissues (Figure 6), suggesting that there are differences in PAQR4 promoter methylation levels in different tumors. Here, PAQR4 is linked to squamous cell lung carcinoma.