The Study On Gene Morphology Of Simultaneous Multifocal Lung Cancer And Preliminary Analysis Of Related Clinical Diagnosis And Treatment

Chapter One:Comparative Molecular Profiling of Distant Metastatic and Nondistant Metastatic Lung AdenocarcinomaObjective:For the efficient prediction and reduction of recurrence rates,it is essential to understand the biology behind distant metastasis(DM).Genome-wide analysis has been widely used to explore the pathogenesis and molecular diagnosis of metastasis in lung adenocarcinoma.Methods:The tumor samples of 215 eligible lung adenocarcinoma patients were subjected to the targeted sequencing using a panel covering the exome of lung cancer-associated driver genes.Tumor gene alterations were analyzed to compare the differences of genetic molecular features between lung adenocarcinomas with or without DM.Results:Significantly more variations in overall copy number(defined as CNA load and CNI score)were identified in patients with DM of lung adenocarcinoma.The degree of copy number variation has a positive correlation with mutations of DDR pathway.These results suggest the contribution of impaired function of the DDR pathway in the invasion process of cancer cells.Conclusions:Our study revealed significant genomic alterations between distant metastatic and nondistant metastatic patients,provides the clues that genomic characteristics of the primary tumor might be a potential predictor of distant metastasis in lung adenocarcinoma.Chapter Two:The Study on Gene Morphology of Simultaneous Multifocal Lung Cancer and Preliminary Analysis of Related Clinical Diagnosis and TreatmentObjective:Distinguishing between Intrapulmonary metastatic(IPM)and multiple primary lung cancer(MPLC)is critical for staging and treatment strategies,further affects the diagnosis and prognosis of patients.Methods:The current study enrolled 11 patients with multifocal lung cancer who underwent surgery Blood cells and tumor tissues from different lesions were subjected to whole exome sequencing(WES)and transcriptome sequencing(RNA-seq)platforms.Copy number alterations,as well as other molecular and immune characteristics were compared between patients with IPM and MPLC.Results:Of the 11 patients,two patients with definite clinicopathologic diagnosis of advanced stage were used as control cases,two patients with pathological diagnosis of MPLC were assessed as IPM by evolutionary analysis,and the other seven patients’ evolutionary analysis were consistent with the pathological diagnosis.Compared with MPLC patients,the IPM patients had a higher frequency of loss of heterozygosity in human leukocyte antigen(LOH HLA)(100%vs.42.9%),and lower T cell infiltration(rank sum test,p<0.05),suggesting immune evasion might lead to lung metastases in IPM cancers.In addition,patients with MPLC had higher tumor mutation burden(TMB)and increased expression levels of immune checkpoint moleculars,suggesting that patients with MPLC might potentially benefit from immunotherapy.Conclusions:Our study revealed the differences in molecular and immune characteristics between patients with IPM and MPLC,and provided potential clues for optimizing personalized immunotherapy for multifocal lung adenocarcinoma patients.Chapter Three:EPHA5 Mutations Predict Survival after Immunotherapy in Lung AdenocarcinomaAbstractObjective:Erythropoietin-producing hepatoma(Eph)receptors,the largest family of receptor tyrosine kinases(RTKs),their association with anti-tumour immunity and immunotherapy in lung adenocarcinoma(LUAD)are still largely unknown.Methods:Comprehensive analysis was performed by integrating genomic,transcriptomic and clinical data from cohorts of LUAD patients in public databases to elucidate the relevance of Eph receptors to anti-tumour immunity.Results:We found that EPHA5 was the most commonly mutated gene of Eph family in LUAD.The infiltration of CD8+T cells and M1 macrophages were increased in the EPHA5-Mut tumors when compared with EPHA5-WT tumors,and the regulatory T cells(Tregs)were reduced.Moreover,the EPHA5-Mut group exhibited enhanced level of anti-tumour immunity-related signatures,mutational burden and immunogenic tumour antigen level,as well as the relatively high proportion of PDL1+/CD8+cells.Further molecular analysis revealed that EPHA5 co-occurred with homologous recombination(HR)and mismatch repair(MMR)pathway related genes mutations.These data were in the LUAD cell line H 1299 and a 143 Chinese LUAD cohort.Notably,patients with EPHA5 mutation had significantly longer survival than those without EPHA5 mutation in a Memorial Sloan-Kettering Cancer Center(MSKCC)immunotherapy LUAD cohort,and all patients with EPHA5 mutation presented durable clinical benefit from immunotherapy in the Hellmann non-squamous NSCLC Cohort.Conclusions:The current study demonstrated the association of EPHA5 mutation with anti-tumour immunity and predictive factors for immunotherapy,implying the potential of EPHA5 mutations as a prognostic marker for immune checkpoint blockade therapy in LUAD patients.