The results showed that C1QA, CIQB, C1QC, CD14, FCER1G, and TYROBP were highly expressed in gastric cancer tissues compared with normal tissues (Supplementary Figure 2), and there were no significant differences in CD163, CSF1R, and MS4A6A. Kaplan–Meier survival analysis in the Kaplan–Meier plotter showed that all hub genes except for CD14 and FCER1G had obvious prognostic value (Supplementary Figure 3). The gene discussed is C1QC; the disease is gastric cancer.