Expression And Clinical Significance Of FAM111B In Hepatocellular Carcinoma

Objective:FAM111B（Family with sequence similarity 111 member B）belongs to the family of FAM111 family,encoding a protein with trypsin like cysteine / serine peptidase domain,which plays an important role in many tumours such as lung cancer,cervical cancer and breast cancer.However,the specific role of FAM111 B in hepatocellular carcinoma（HCC）is unclear.In this study,bioinformatics methods were used to explore the expression and clinical significance of FAM111 B in HCC,to predict the potential regulatory mechanism of abnormal expression and the involved signaling pathways and biological functions.The expression of FAM111 B in HCC was experimentally verified and analyzed.Finding the relationship between the expression level of FAM111 B and the clinical characteristics of HCC.The aim is to provide some help for the diagnosis,treatment and prognosis evaluation of patients with HCC.Methods:1.Bioinformatics analysisHPA database,GEPIA database and TIMER database were used to analyze the expression level of FAM111 B in human normal organs and different tumors,and then combined with c Bio Portal database and COSMIC database to analyze the mutation sites,mutation types and nucleotide changes of FAM111 B in HCC.Then,the expressions of FAM111 B in HCC,the relationship between the expression of FAM111 B and the clinical characteristics and prognosis of patients were analyzed by using GEPIA database,TCGA database,ICGC database and GEO database.In addition,combined with c Bio Portal database,mi RDB database,mi RWalk database,Target Scan database and TCGA database,the potential regulation mechanism of abnormal expression of FAM111 B was discussed from the level of methylation,copy number variation and mi RNAs.Based on CIBERSORT algorithm and p RRophetic algorithm,the relationship between the expression level of FAM111 B and immune cell infiltration and drug sensitivity was evaluated.Finally,the signal pathways and biological functions of FAM111 B in HCC were enriched and analyzed.2.Experimental verificationThe expression of FAM111 B in three pairs of HCC tissues and paired adjacent tissues was verified by Western blot.Immunohistochemistry verified the expression and difference of FAM111 B in 25 cases of HCC and adjacent tissues.At the same time,combination the expression data of FAM111 B in HCC with the clinical data of patients,the relationship between the expression of FAM111 B and the clinical characteristics of patients was analyzed.Results:1.Results of bioinformatics analysisThe expression levels of FAM111 B were low in human normal tissues,and the expression level of FAM111 B is also low in normal liver tissues.Trypsin＿2 was the most common mutation site of FAM111 B in HCC.Missense mutation was the most common mutation type of FAM111 B in HCC（62.50%）,followed by synonymous mutation（25.00%）and frameshift mutation（12.50%）.Nucleotide changes mainly include A > G,C >T,G > A,G > T,T > A and T > C mutations,of which T > A mutation accounts for the largest proportion（28.57%）.The results of difference analysis showed that the expression level of FAM111 B in HCC was significantly higher than that in normal liver tissue（p<0.05）.The correlation analysis between the expression level of FAM111 B and the clinical characteristics of HCC showed that the expression level of FAM111 B was closely related to serum AFP level,T stage,clinical stage and histological grade（p<0.05）.Survival analysis showed that patients with high expression of FAM111 B had a worse prognosis than those with low expression of FAM111B（p<0.05）.Multivariate Cox regression analysis showed that FAM111 B expression level and clinical stage were independent risk factors affecting the prognosis of patients with HCC.The nomogram prediction model of HCC based on FAM111 B expression level and clinical stage showed a good predictive effect.The decrease of FAM111 B methylation level and the down-regulation of mi R-511-5p expression were significantly correlated with the up-regulation of FAM111 B expression.In addition,B cell plasma,T cell CD4+ memory resting,T cell CD4+ memory activated,T cell follicular helper and neutrophil and other immune cell infiltration levels were significantly different between high and low expression groups of FAM111B（p<0.05）;Moreover,the expression level of FAM111 B was positively correlated with the infiltration level of B cell plasma,T cell CD4+ memory activated,T cell follicular helper and neutrophil,and negatively correlated with T cell CD4+ memory resting.Drug sensitivity analysis showed that the IC50 value of sorafenib in the high FAM111 B expression group was higher than that in the low FAM111 B expression group（p<0.05）.Enrichment analysis showed that FAM111 B was involved in DNA replication,nuclear chromosome separation,hydrolysis of nucleic acid phosphodiester bond,positive regulation of cell cycle process and signal transduction by p53 class mediator,and enriched in basal transcription factors,cell cycle,DNA replication,homologous recombination,nucleotide excision repair,p53 and other signal pathways.2.Results of experimental verificationWestern blot showed that the expression level of FAM111 B in HCC was higher than that in adjacent tissues（p<0.05）.Immunohistochemistry showed that FAM111 B was highly expressed in 64%（16/25）patients with HCC,and its expression level was related to the clinical stage of HCC（p=0.041）,but not to age,gender,serum AFP level and T stage.Conclusion : The expression level of FAM111 B in HCC was significantly increased,and its up-regulation was closely related to the disease progression and poor prognosis of patients;The decrease of FAM111 B methylation level and the downregulation of mi R-511-5p expression may be the potential regulatory mechanism of the up-regulation of FAM111 B expression;The expression level of FAM111 B is related to the infiltration of many immune cells and drug sensitivity;FAM111B is involved in DNA replication,nuclear chromosome separation,hydrolysis of nucleic acid phosphodiester bond,positive regulation of cell cycle process and signal transduction by p53 class mediator,and enriched in basal transcription factors,cell cycle,DNA replication,homologous recombination,nucleotide excision repair,p53 and other signal pathways.