The Role Of CD55 In Colorectal Cancer And Its Upstream Regulatory Mechanism

As a membrane-bound complement regulatory protein,CD55 is involved in the occurrence of various cancers.However,whether CD55 is involved in the occurrence and development of colorectal cancer by regulating upstream transcription factors and miRNAs has not been clarified.The regulatory mechanism of CD55 in the occurrence and development of colorectal cancer was analyzed.The data of TCGA database were used to analyze the difference in the expression of CD55 in colorectal cancer tissues and adjacent normal tissues,and to analyze the correlation between expression of CD55 and prognosis and clinical staging.The GO and KEGG analysis of CD55 and its interacting proteins were performed by String database using R language.The upstream regulatory factors binding to CD55 were predicted through databases;the effect of NF-κB on the transcriptional activity and expression of CD55 were detected by dual-luciferase reporter gene assay,et al.A case-control study was used to analyze the relationship between the genetic variation of rs2564978 T>C in the CD55 promoter and the risk of colorectal cancer.The results showed that CD55 was highly expressed in cancer tissues and had no effect on histological staging and prognosis of colorectal cancer.The expression of CD55 in mucinous adenocarcinoma was higher than that in adenocarcinoma.GO and KEGG analysis showed that CD55 and its interacting proteins were mainly enriched in immunerelated pathways such as complement-related pathways,suggesting that CD55 may be a key immune gene in the organism.Bioinformatic analysis indicated that CD55 could bind to transcription factors and miRNAs.NF-κB could affect the transcription activity of the CD55 promoter and promote the expression of CD55.The genetic variation of rs2564978T>C in the CD55 promoter could increase the risk of rectal cancer(OR=1.48,95%CI=1.02～2.15),but had no effect on the risk of colon cancer.The above-mentioned exploration provides a basis for elucidating the molecular mechanism of CD55.CD55 can be used as an indicator of the incidence of colorectal cancer.Figure 19;Table 11;Reference 109...