The Study On Gene Mutations Of Esophageal Squamous Cell Carcinoma Based On Next-generation Sequencing

Objective: To explore potential molecular targets in Esophageal squamous cell carcinoma(ESCC),we quantified the mutation spectrum and explored the relationship between gene mutation and clinicopathological characteristics and PD-L1 expression.Methods: Targeted next-generation sequencing(NGS)was performed on 29 surgically resected ESCC patients using a 520-cancer-gene panel,and sequencing data was analyzed using bioinformatics methods.Tumor mutation burden(TMB)and microsatellite-instability(MSI)were also estimated by gene detection.The expression levels of PD-L1 were detected by immunohistochemistry(IHC).Results:1.The most frequently mutated gene was TP53(96.6%),followed by NOTCH1(27.6%),EP300(17.2%),and KMT2C(17.2%).The most frequently copy number amplified and deleted genes were CCND1/FGF3/FGF4/FGF19(41.1%)and CDKN2A/2B(10.3%).2.By quantifying the relevant contributions of COSMIC mutational signatures to each sample,six dominant signatures were identified,including signature 1,signature 2 and 13(APOBEC-mediated mutational signatures),signature 10,signature 12 and signature 17.3.The cell cycle signaling pathway,chromatin modification signaling pathway,JAK-STAT and Notch signaling pathway related gene mutation rates were 96.6%,79%,75.9% and 48.3%,respectively.4.Evaluation of PD-L1 expression in samples,13.8%(4/29)samples with TPS ≥1%.17.2% of patients had TMB above 10mut/Mb.All samples were microsatellite stability(MSS).5.Relationship between gene mutation and clinicopathological characteristics and PD-L1 expression: KMT2 D mutation was associated with lymph node metastasis(P=0.03).CCND1/FGF3/FGF4/FGF19 amplification was correlated with the degree of differentiation(P=0.03).The CCND1/FGF3/FGF4/FGF19 amplification and CDKN2 A deletion were related to the depth of infiltration(P=0.02,P<0.001,respectively).TMB was associated with lymph node metastasis(P=0.02),and was not significantly associated with smoking and PD-L1 expression.No significant correlation between PD-L1 expression and detected gene mutations.Conclusions:1.ESCC-associated gene mutation profiles were preliminarily constructed in high-incidence areas.Mutational signature 1,APOBEC-mediated mutational signature,mutational signature 10,mutational signature 12,and mutational signature 17 were identified as dominant signatures in 29 ESCC patients.2.Cell cycle,chromatin modification,JAK-STAT,and Notch signaling pathway may be involved in the development and progression of ESCC.3.KMT2 D mutation,CCND1/FGF3/4/19 amplification,and CDKN2 A deletion may be new prognostic factors for ESCC.4.No significant correlation was found between PD-L1 expression and TMB and ESCC gene mutation profiles detected.