IL2 and colorectal carcinoma: To further evaluate the role of genes corresponding to the HRGS, GSEA was performed in TCGA CRC cohort and found that the hypoxia environment was statistically related to interferon α (IFN-α), IFN-γ, interleukin 6 (IL-6), and IL-2 (Figure 4B), which are important components of the immune response network.