Part ? Clinical Significance And Mechanism Of LIFR Gene In Intrahepatic Cholangiocarcinoma Part ? Prognostic Value Of Lymph Node Dissection For Intrahepatic Cholangiocarcinoma

Part I Clinical significance and mechanism of LIFR gene in intrahepatic cholangiocarcinomaBackgroundLeukemia inhibitory factor(LIF)is a kind of cytokine with strong pleiotropic properties,which widely exists in every system.LIF is expressed in many malignant tumors.In TCGA database,the expression of LIF in cancer tissues was significantly higher than normal tissues in several cancers,especially in pancreatic cancer and intrahepatic cholangiocarcinoma(ICC).Some studies have shown that LIF can promote the development of pancreatic cancer and has the potential as a therapeutic target and biological marker.ICC accounted for about 10%of primary liver malignant tumors,ranking the second.ICC has insidious onset and high malignancy.At present,surgery is still the only effective treatment.Some studies have found that LIF is related to the growth,invasion,and drug resistance of ICC,but its role in ICC remains unclear.This study aims to explore the possibility of LIF/LIFR as a novel biological marker and therapeutic target of bile duct cell carcinoma by studying the role of LIFR gene in bile duct cell carcinoma and its mechanism.Methods1.Lentiviral vectors carrying shRNA and LIFR genes were used to construct stable LIFR knockdown and overexpression cell lines.2.Real-time fluorescent quantitative PCR and Western blot were used to detect LIFR expression before and after adj ustment of LIFR gene expression from mRNA and protein levels.3.CCK-8 assay was used to detect its effect on proliferation of intrahepatic bile duct cancer cells,and clone formation assay was used to detect its effect on cell clone formation ability.4.Western blot was used to detect the expression of related molecular signaling pathways and stem-cell related proteins.5.Retrospectively collected paraffin specimens from ICC surgery were used to make tissue microarray to analyze the relationship between LIF/LIFR expression and prognosis.6.Public databases were used to explore the relationship between LIF/LIFR expression and mutation and prognosis in bile duct cancer cells.7.Explore the relationship between LIF/LIFR gene methylation and expression using public databases.Results1.After shRNA/LIFR gene was transfected by lentiviral vector,the expression levels of LIFR-mRNA and LIFR protein were significantly decreased/increased.2.The knockdown/overexpression of LIFR had no significant effect on cell proliferation rate.3.The knockdown of LIFR had no significant effect on the ability of cell clone formation;Overexpression of LIFR can enhance the ability of cell clone formation.4.P-STAT3 protein expression was upregulated after LIFR overexpression.5.LIFR knockdown/overexpression had no significant effect on stem-cell related protein expression levels.6.Data from both tissue microarray and public databases indicated that there was no statistically significant difference in the prognosis of ICC patients with different LIF/LIFR expression levels.7.There are differences in the expression levels of LIF/LIFR in carcinomas and paracancerous tissues.8.LIF/LIFR was negatively correlated with the gene methylation level.Conclusions1.Lentiviral vectors can effectively construct stable LIFR knockdown/overexpression cell lines.2.LIF/LIFR may regulate ICC through STAT3 signaling pathway.3.The expression level of LIFR was not related to ICC proliferation rate and clone formation.4.Differences in LIF/LIFR expression levels had no significant effect on the prognosis of ICC.5.DNA methylation may be related to changes in LIF/LIFR expression.Part ? Application of lymph node dissection in intrahepatic cholangiocarcinomaIntroductionLymph node dissection(LND)is of great significance in intrahepatic cholangiocarcinoma(ICC).Although The National Comprehensive Cancer Network(NCCN)guidelines recommend routine LND in ICC,the effects of LND remains controversial.This study aimed to explore the role and application of LND in ICC.MethodsPatients were identified in two Chinese academic centers.Inverse probability of treatment weighting(IPTW)was used to reduce bias.Kaplan-Meier curves and Cox proportional hazards models were used to compare overall survival(OS)and disease-free survival(DFS).ResultsOf 232 patients,177(76.3%)underwent LND,and 71(40.1%)had metastatic lymph nodes.A minimum of 6 lymph nodes were dissected in 66 patients(37.3%).LND did not improve the prognosis of ICC.LNM>3 may have worse OS and DFS than LNM 1-3,especially in the LND>=6 group.For nLND patients,the adjuvant treatment group had better OS and DFS.ConclusionsLND did not improve patient outcomes.LND was more likely to be performed in patients with advanced tumors.Patients with 4 or more LNMs may have a worse prognosis than those with 1-3 LNMs.Adjuvant therapy may benefit for nLND patients.