| Hepatocellular carcinoma(HCC),the main form of primary liver cancer,is the fifth most common malignant cancer worldwide.Responsible for the death of more than two hundred and fifty thousand around the world annually,liver cancer has been ranked third in tumor fatality rate.China,as a country with fairly high liver cancer incidence rate,contains more than 50% emerging and dead liver cancer patients worldwide.Epidemiological and experimental data indicates that factors like hepatitis B virus(HBV),hepatitis C virus(HCV),aflatoxin,alcohol,etc are primary causes of liver cancer in China.According to related researches,most HCC patients will typically suffer first from hepatitis,followed by cirrhosis,and then HCC..At present,the five-year survival rate of HCC has not reaeced 10%.Most HCC patients lose out on the chance of receiving operations due to the challenges of early diagnosis.Therefore,it is especially important to diagnose HCC in its early stage.Currently,tissue biopsy and pathological examination are the “gold standard” for HCC diagnosis.However,the invasiveness of these diagnostic methods has restricted their application.As a preferred marker for HCC since its discovery in the 1960 s,the sensitivity of AFP(Alpha fetoprotein)is only about 60%,and it also appears to increase in cases of non-HCC diseases,such as cirrhosis and inflammation,causing unsatisfactory diagnostic effect.With development of molecular biology and completion of human genome sequencing,more and more attention has been paid to the application of genomics,proteomics,and glycomics with respect to liver diseases.The occurrence and development of HCC is a complex biological process,which includes various kinds of proteins being involved,while more than half of the protein molecules in serum happen to be glycosylated.AFP-L3,namely core-fucosylated AFP,has been adopted as a diagnostic and prognostic indicator for HCC by the Food and Drug Administration(FDA)since 2005.Therefore,research on protein glycosylation and its relation to the occurrence and development of HCC plays a significant role in the diagnosis and prognosis of liver diseases.The field of quantitative proteomics has also made great progress in recent years,mass spectrum(MS)-based quantitative proteomics has increasingly been applied for clinical use.This study focuses its attention on protein fucosylation,discussing the clinical significance of protein fucosylation in HCC from three aspects.Part 1: Lectin affinity enrichment of differentially expressed proteins in serum of primary hepatocellular carcinomaThe aim of this study is to screen the differentially expressed core-fucosylated proteins in serum from healthy controls(HC),patients with liver cirrhosis(LC)and patients with primary hepatocellular carcinoma(HCC).Based on the method of screening followed by verification,the aim of this study is to screen the differentially expressed glyco-proteins by combining different mass spectrometry techniques.Samples from HC,LC,and HCC group were collected,core-fucosylated proteins in which were specially absorpted to LCA and enriched.Mass spectrometry was used to detect and analyze the differentially expressed glyco-proteins among the three groups.Then the samples were expanded and the results were verified by two different mass spectrometry methods.Results: Synthesis of the results of preliminary screening and two different mass spectrometric verification methods,differential core-fucosylated proteins between LC and HC group include serum amyloid p-component,pregnancy zone protein,and haptoglobin-related protein,the level of core-fucosylation of these three proteins in HC group is obviously higher than that in LC group.Differential glyco-proteins between HCC and HC group are sex hormone binding protein and polymeric immunoglobulin receptor.Core-glycosylation level of proteins in HCC group is higher than that in the HC group.The differential glyco-proteins existing between the groups HCC and LC are the serum amyloid p-component,haptoglobin,transthyretin,and apolipoprotein L1.The core-fucosylation level of these proteins in the HCC group is higher than that in the LC group.Conclusions: Taking advantage of high-resolution mass spectrometry technique,we identified differentially expressed protein through its glycosylation level.Depending on the results,core-fucosylated serum amyloid p-component,pregnancy zone protein,and haptoglobin-related protein possess potential to differentially diagnose LC from HC.Core-fucosylated sex hormone binding protein and polymeric immunoglobulin receptor possess potential to diagnose HCC out of HC.Core-fucosylated serum amyloid p-component,haptoglobin,transthyretin,and apolipoprotein L1 possess potential to diagnose LC out of HCC.Part 2:Analysis of four special glyco-protein for their diagnosis value and operation effect judgment of HCCBy searching for related articles and taking clinical operability into account,the research focuses on the relation between ferritin,IgG,?2-M,transferrin,its corresponding core-fucosylated part,and HCC.This research further clarifies the significance of these items for the evaluation of the HCC radical resection effect.It appears that there are differences between HCC group and non-HCC group in the level of percentages of core-fucosylated Fer,?2-M,percentages of core-fucosylated?2-M and Trf.Percentages of core-fucosylated IgG and percentages of core-fucosylated Trf present positive correlation with AFP-L3%.Further analysis shows that the positive diagnostic rates of AFP and AFP-L3% are higher than those of the other 4 kinds of proteins and their corresponding fucosylated levels,while among four kinds of proteins and their fucosylation levels,?2-M and its core-fucosylation percentages are ranked first and second in their respective group.Combined diagnosis of AFP,?2-M and percentages of core-fucosylated ?2-M could improve early detection sensitivity rate of HCC from less than 85% to 90%.Percentages of core-fucosylated Trf appear in positive correlation with HCC tumor size.In 30 cases of radical resection of liver cancer,core-fucosylated Fer,percentages of core-fucosylated Fer,IgG,core-fucosylated IgG,core-fucosylated Trf present differences before and after radical resection,of which core-fucosylated Fer,percentages of core-fucosylated Fer decrease after operation.Differential markers pre-and post-operation include core-fucosylated Fer,percentages of core-fucosylated Fer,IgG,core-fucosylated IgG,percentages of core-fucosylated IgG,Trf,and core-fucosylated Trf in the AFP obvious change group.Among these indicators,IgG,core-fucosylated IgG,Trf,and core-fucosylated Trf increase after the operation.In the group where AFP does not change obviously after operation,IgG,core-fucosylated ?2-M,and percentages of core-fucosylated ?2-M appear different after radical resection;core-fucosylated ?2-M and percentages of core-fucosylated ?2-M decrease after the operation.In summary,depending on the diagnostic value core-fucosylated ?2-M and percentages of core-fucosylated ?2-M possess and their correlation with tumor size,core-fucosylated ?2-M and percentages of core-fucosylated ?2-M possess potential value for early detection and gauging the operation effect of HCC. |
PDF Full Text Request