Proteomic Study Of Bile Proteins In Bile Duct Carcinoma With Obstructive Jaundice

Background: Cholangiocarcinoma(CC)is malignant tumors,originated from bile duct epithelial cells,a high degree of malignancy,is not sensitive to radiotherapy and chemotherapy,the prognosis is poor,five-year survival rate is close to zero.In recent years the incidence rate showed a significant upward trend.Complete surgical resection is the only effective clinical treatment of cholangiocarcinoma,but due to cholangiocarcinoma insidious onset,the current restrictions on image and other detection,most patients have been found unable to radical surgical resection,so early detection,early diagnosis is extremely important to improve the prognosis of cholangiocarcinoma.The purpose of this study was use the proteomics and other means to filter out potential human bile of cholangiocarcinoma biomolecular markers in cholangiocarcinoma and validate their corresponding diagnostic effectiveness.Methods: This study collected the clinical cholangiocarcinoma and cholelithiasis patients' bile by high performance reverse liquid chromatography(RPLC)and liquid ion trap mass spectrometer(LC-MS/MS)technology combined with construction of complete protein expression differences in human bile.Further using the STRING database of these proteins for bioinformatics analysis of combined disease the current progress of the study,selected LCN1 and PTTG1 IP as a potential biomarker,by enzyme-linked immunosorbent assay(ELISA)detection the expression level of LCN1 and PTTG1IP in bile of CC and cholelithiasis patients,evaluate the diagnostic value ofnew markers.Then from the cell level by Western blot to verified and analyzed the expression of these two proteins.Results: The RPLC-MS/MS had detected 1985 proteins,found a total of 285 differential expression proteins,198 of which are in the bile of CC patients with significantly higher expression,87 proteins in the bile of CC patients with low expression.Then we combine the study of protein present differences in query related information,randomly selected from LCN1 and PTTG1 IP of this two proteins,verified by ELISA in 51 cases of individual patients bile samples,the results show that these 2proteins were highly expressed in the bile of patients with CC.And we use ELISA for LCN1 and PTTG1 IP expression levels in CC,cholelithiasis bile quantitative analysis,the results suggest LCN1 and PTTG1 IP can be well separated from the CC and cholelithiasis patients with cholangiocarcinoma area,the sensitivity and specificity were80%,92% and 60%,92%.Meanwhile,western blot cholangiocarcinoma cells and normal biliary epithelial cells of thesamples also showed that the expression of these two proteins in tumor cells was significantly higher than in normal cells.LCN1 and PTTG1 IP these two markers in the diagnosis of cholangiocarcinoma was significantly better than CA19-9,CEA,AFP and other indicators can improve the diagnosis of cholangiocarcinoma reliability.Conclusion: In summary,we have successfully completed the construction of cholangiocarcinoma bile protein differences lineage,made the tumor associated marker candidate CC library diagnosis of high value.Subsequent studies also clearly suggest LCN1 and PTTG1 IP great potential as a diagnostic marker of CC and molecular targets for cancer treatment.