Correlation between low expression of IgG Fc binding protein and prognostic indicators of colon adenocar-cinoma

He Miao; Wang Qi; Sun Xing; Xu Quanxiao

doi:10.3760/j.issn.1673-4777.2024.02.020

Abstract：Objective To investigate the correlation between the low expression of IgG Fc binding protein(FCGBP)and the prognostic indicators of colon adenocarcinoma.Methods A total of 455 patients with colon adenocarcinoma tumor tissue data(observation group)and 41 patients with paracancerous tissue data(control group)were collected from TCGA database and Genotype tissue expression database.Taking the middle value of FCGBP expression level(6.126 TPM)as the standard,the patients in the observation group were divided into FCGBP high expression group(228 cases)and FCGBP low expression group(227 cases).After excluding the patients who were lost to follow-up,the patients in the observation group were divided into the metastasis group(52 cases)and the non-metastasis group(333 cases)according to whether they had metastasis.The general datas of patients in the FCGBP high expression group and the FCGBP low expression group were compared,and the expression levels of FCGBP mRNA in the observation group and the control group were compared,and the expression levels of FCGBP mRNA in the metastasis group,the non-metastasis group and the control group were compared.Kaplan-Meier curve was drawn by Log-rank test to analyze the survival of patients in the metastasis group and the non-metastasis group.Cox regression analysis was used to evaluate the prognostic value of FCGBP gene expression in colon adenocarcinoma.The correlation between the expression of FCGBP gene and the level of immune cell infiltration was analyzed by Spearman correlation analysis and plotted.Results The proportions of invasion depth of T3-T4,clinical stage of Ⅲ-Ⅳ,lymph node metastasis and distant metastasis in the FCGBP high expression group were lower than those in the FCGBP low expression group,the proportions of invasion depth of Tl-T2 and clinical stage of Ⅰ-Ⅱ in the FCGBP high expression group were higher than those in the FCGBP low expression group(all P＜0.05).The relative expression levels of FCGBP in the metastasis group and the non-metastasis group were lower than those in the control group[(5.0±2.1)TPM,(5.9±2.1)TPM vs(9.5±1.0)TPM],and the metastasis group was lower than the non-metastasis group(all P＜0.05).Kaplan-Meier survival analysis showed that the median survival time of the metastasis group was lower than that of the non-metastasis group(2.1 years vs 8.2 years,Log-rank P＜0.001).Cox regression analysis showed that the lower the expression level of FCGBP,the shorter the overall survival time and the worse the prognosis of patients(hazard ratio=4.434,95％confidence interval:2.778-7.077,P＜0.001).Spearman correlation analysis showed that the expression of FCGBP gene in patients with colon adenocarcinoma was positively correlated with the infiltration level of B lymphocytes,CD4+T cells,CD8+T cells,neutrophils and dendritic cells(all P＜0.05).Conclusion Low level of FCGBP mRNA is associated with poor prognosis of patients with colon adenocarcinoma,and is closely related to immune infiltration of colon adenocarcinoma,which is expected to be a prognostic biomarker of colon adenocarcinoma.