1.The Research Of Genetic Mutation And PD-L1 Expression In Patients With Squamous Cell Lung Carcinoma 2.Prognostic Value Of MiRNA In Early Pancreatic Ductal Cell Adenocarcinoma

Part Ⅰ The Research of genetic mutation and PD-L1 expression in patients with squamous cell lung carcinomaObjective:To detect the relationship between key mutations and PD-L1 expression and explore the clinical significance of mutant genes in guiding immunotherapy.Methods:We retrospectively analyzed the medical history and follow-up information of squamous cell lung carcinoma patients diagnosed and treated in PLA General Hospital from January 2015 to January 2019.we collected archived Formalin-Fixed Paraffin-Embedded specimens for detecting mutant genes by NGS technology and tested the expression of PD-L1 via immunohistochemistry.Lastly,the relationship of the mutant gene,PD-L1 expression,clinical pathological features and efficacy of immunotherapy were analyzed with Graphpad prism 8.0 software.Results:1.Amount to 314 mutation types of 110 tumor-associated genes were detected.TP53(69%),PIK3CA(33%),HER2(23%),FGFR1(21%),PTEN(21%),and VEGFR2(21%)are among the most commonly mutations.2.The range of PD-L1 expression was from 0 to 100%,with a median expression value of 10%.The positive rates of PD-L1 expression were 82.1%,71.8%,28.2%and 15.4%,respectively,according to cut off values of 1%,5%,25%,and 50%.3.PD-L1 expression was associated with KPS scores and lymph node metastasis.When the positive cutoff value is 5%,patients with PD-L1 positive expression have a relatively high KPS<90.When the positive cutoff values were 25%and 50%,the patients with PD-L1 positive expression had a relatively high KPS=90.When the positive cut-off value is 50%,the PD-L1 negative patients have a higher tendency to metastasize to the contralateral hilar lymph nodes,mediastinal lymph nodes,ipsilateral or contralateral scalene muscles or supraclavicular lymph nodes than the positive patients.4.PD-L1 expression is associated with mutations in the TP53,PIK3CA,ROS1,and MLH1 genes.PD-L1 expression was associated with mutations in the TP53,PIK3CA,ROS1,and MLH1 genes at different positive cutoff values.When the positive cutoff value was 1%,the mutation rate of TP53 gene mutation in PD-L1 positive expression group had a higher trend.When the positive cutoff value was 5%,the incidence of TP53 and PIK3CA mutations was higher in the PD-L1 positive group.When the positive cutoff value was 50%,the ROS1 gene mutation(non-gene fusion mutation),PIK3CA and MLH1 appeared more frequently in the PD-L1 expression negative group.5.The higher PD-L1 expression,the more benefits from immunotherapy.Unluckily,this study did not show clear evidence for gene mutations as a guidance for immunotherapy due to the limited samples.Conclusion:Squamous cell lung carcinoma is characterized by unique pathological and molecular features.The expression of PD-L1 in squamous cell lung carcinoma was relevant to KPS score,lymph node metastasis and TP53,PIK3CA,ROS1 and MLH1 gene mutations.The higher PD-L1 expression,the more benefits from immunotherapy.The clinical significance of gene mutations in guiding immunotherapy remains to be confirmed by further analysis.Part Ⅱ Prognostic value of miRNA in early pancreatic ductal cell adenocarcinomaObjective:Applying weighted gene co-expression network analysis(WGCNA),the miRNA expression profile data of PDAC patients were analyzed to identify some key miRNAs that affect the development and progression of PDAC,and to explore its potential biological mechanisms.And then construct a miRNA prognosis prediction model for PDAC.Methods and materials:In this study,miRNA expression profiles and corresponding clinical data of patients with PDAC were obtained from the Cancer Genome Atlas(TCGA)database.The WGCNA method was used to construct a co-expression network to detect miRNA gene modules that were significantly associated with some clinical features.Biological function annotation of pivotal miRNAs in miRNA modules associated with clinical features was performed by Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment analysis.Finally,a prognostic model consisting of pivotal miRNAs was constructed using the Rebust likelihood-based survival model in the R language package ’rbsurv’ and verified by survival analysis.Results:The expression data of 523 miRNAs in 124 patients with PDAC were analyzed in a co-expression network.The turquoise module containing 131 miRNAs was identified to be associated with pathological T stage(cor=-0.21;P=0.02).The 39 hub miRNAs of the turquoise module were then detected using the ’network-Screening’ function in R.These miRNAs were predominantly involved in biological processes including ’regulation of transcription’,’apoptotic process’,’TGF-β receptor signaling pathway’,’Ras protein signal transduction’ and significantly enriched in ’cell cycle’,’adherens junction’,’FoxO’,’Hippo’ and ’PI3K-Akt signaling’ pathways.A prognostic signature consisting of four hub miRNAs(miR-1197,miR-218-2,miR-889 and miR-487a)associated with pathological T stage was identified to stratify the patients with early-stage PDAC into high and low risk groups.Conclusion:The signature consists of 4 hub miRNAs(miR-1197,miR-218-2,miR-889 and miR-487a)may serve as a potential prognostic biomarker for patients with early-stage PDAC who undergo radical resection.