Two mRNA (TBC1D2 and ATP6V0E1) in green module and six mRNAs (SPI1, RNASE6, C1QB, C1QC, CSF1R, and C1QA) in cyan module were considered as real hub mRNAs, and they were closely related to the overall survival in ESCC (Figure 4). Here, C1QA is linked to esophageal squamous cell carcinoma.