摘要
BACKGROUND Colon cancer(CC)occurrence and progression are considerably influenced by the tumor microenvironment.However,the exact underlying regulatory mechanisms remain unclear.AIM To investigate immune infiltration-related differentially expressed genes(DEGs)in CC and specifically explored the role and potential molecular mechanisms of complement factor I(CFI).METHODS Immune infiltration-associated DEGs were screened for CC using bioinformatics.Quantitative reverse transcription polymerase chain reaction was used to examine hub DEGs expression in the CC cell lines.Stable CFI-knockdown HT29 and HCT116 cell lines were constructed,and the diverse roles of CFI in vitro were assessed using CCK-8,5-ethynyl-2’-deoxyuridine,wound healing,and transwell assays.Hematoxylin and eosin staining and immunohistochemistry staining were employed to evaluate the influence of CFI on the tumorigenesis of CC xenograft models constructed using BALB/c male nude mice.Key proteins associated with glycolysis and the Wnt pathway were measured using western blotting.RESULTS Six key immune infiltration-related DEGs were screened,among which the expression of CFI,complement factor B,lymphoid enhancer binding factor 1,and SRY-related high-mobility-group box 4 was upregulated,whereas that of fatty acid-binding protein 1,and bone morphogenic protein-2 was downregulated.Furthermore,CFI could be used as a diagnostic biomarker for CC.Functionally,CFI silencing inhibited CC cell proliferation,migration,invasion,and tumor growth.Mechanistically,CFI knockdown downregulated the expression of key glycolysis-related proteins(glucose transporter type 1,hexokinase 2,lactate dehydrogenase A,and pyruvate kinase M2)and the Wnt pathway-related proteins(β-catenin and c-Myc).Further investigation indicated that CFI knockdown inhibited glycolysis in CC by blocking the Wnt/β-catenin/c-Myc pathway.CONCLUSION The findings of the present study demonstrate that CFI plays a crucial role in CC development by influencing glycolysis and the Wnt/β-catenin/c-Myc pathway,indicating that it could serve as a promising target for therapeutic intervention in CC.