Further, we examined the promoter methylation levels of DELMRGs and found that several genes (such as OAS2, KALRN, SLC16A7, PER2) had significantly lower methylation levels in tumor samples, while several genes (SLC6A3, CDO1, and SERPINC1) were significantly higher methylated (Figure 2C). The gene discussed is CDO1; the disease is neoplasm.