The Expression And Analysis Of PD-L1 In The Primary Tumor Of Non-small Cell Lung Cancer And Circulating Tumor Cells In Peripheral Blood

Part ?:Characterization of the expression of PD-L1 and CD47 expression and infiltration of tumor associated leukocytes in non-small cell lung cancerPurpose:Immunotherapy is one of the most promising advances in the field of oncology.However,limited information exists regarding characterization of the immune microenvironment in patients with NSCLC,by which it may possible to predict the efficacy of novel immunotherapies.Methods:191 resected NSCLC specimens were retrospectively studied for the expression of CD47,PD-L1 using immunohistochemistry(IHC)and immunofluorescence(IF),respectively.Dual-IF was also used for study of infiltrations of CD8+ T cells,M2-macrophages(CD68+CD163+)and M 1-macrophages(CD68+CD163-).Finally,the prognostic role of these immune features was assessed in stage ?a NSCLC.Results:CD47 and PD-L1 were expressed in 53.4%and 55.5%of NSCLCs,respectively.CD47 expression was more frequently detected in adenocarcinoma,female,never-smoking,stage ?a,and high-differentiation NSCLCs(P<0.001,P=0.002,0.008,0.035 and 0.001,respectively).PD-L1 expression was more frequently detected in lung squamous cell carcinoma(P=0.043),and associated with CD8+T cell and M2 macrophage infiltration(P=0.015;P<0.001).Patients expressing CD47 showed poor DFS(22.03 ms vs 34.77 ms,P=0.021;19.97ms vs 34.77ms,P=0.005).But no relationship was found between PD-L1 expression and the DFS of patients with IIIA NSCLC.Conclusions:Expression of CD47 and PD-L1 were elevated in NSCLC,and may play important roles in progression of NSCLC.Targeting CD47 and PD-L1 could offer much promise as effectors of cancer immunotherapy.Part ?:Prognostic significance of circulating tumor cells in non-small cell lung cancer patientsPurpose:The utility of circulating tumor cells(CTCs)as prognostic biomarkers in non-small cell lung cancer(NSCLC)is inconclusive due to the limitations of current CTC detection methods.Using a novel high-efficiency detection method,we determined the ability of CTCs to predict survival and chemotherapeutic responses in advanced NSCLC.Methods:CTCs were enumerated with a novel high-efficiency detection method from the blood of 170 patients with advanced NSCLC at baseline and during follow-up.Patients were stratified into favorable and unfavorable groups with baseline CTC counts of<8 or>8 CTCs/3.2 ml,respectively.Results:Median overall survival(OS)and progression-free survival(PFS)were longer in patients with baseline CTC counts<8 CTCs/3.2 mL.A multivariate analysis demonstrated that baseline CTC count was an independent negative prognostic factor for survival.Patients with post-treatment increases in the CTC count had poorer OS and PFS than those without increases(12.0 vs.13.3 months[P = 0.028]and 5.2 vs.6.4 months[P =0.022],respectively).There was no association between the baseline CTC count and chemotherapeutic response(P = 0.734).However,patients with increased post-treatment CTCs had higher PD rate than those whose without increased post-treatment CTCs(15.6%vs2.40%,P=0.042).Conclusion:The baseline CTC count and the change in the CTC count during treatment were both valuable prognostic indicators for NSCLC.Part ?:Evaluation of circulating tumor cell PD-L1 expression in non-small cell lung cancerPurpose:Immune checkpoint inhibitors have gained promising success in the treatment of advanced non-small cell lung cancer(NSCLC).There are currently no validated predictive biomarkers to select patients likely to respond to anti-PD-1/PD-L1 therapy.A circulating tumor cell(CTC)PD-L1 assay was investigated to test if it can detect PD-L1 expression level in CTC and potentially predict the efficacy of immune checkpoint blockade therapy.Methods:From August,2017 to March,2018,patients with stage ?/? NSCLC were enrolled in this prospective study.CTCs were enumerated with a novel high-efficiency detection method from the blood of all patients at baseline,followed by PD-L1 and CD8+staining using immunofluorescence staining.Results:Of patient samples with CTCs,25/35 had one or more PD-L1 + CTCs.12 cases presented weak positive staining;6 cases strong positive staining.No association was observed between the PD-L1 expression and patient clinicopathological features including age,histology type,TNM stage,EGFR status,smoking history,metastases.Samples with PD-L1 expressing were frequently observed together with CD8+ T cell infiltration.Patients with high fraction of positive PD-L1 cells in their tumor tissue also had PD-L1 "+"or "++" CTCs,while those with low fraction or negative PD-L1 cells had PD-L1 "-"or"+" CTCs.Conclusions:In this part,we provide evidence that PD-L1 is frequently expressed on circulating tumor cell in the blood of advanced NSCLC patients,with a similar pattern compared with their counterparts expressed on tumor tissue.Standardized automated analysis of CTCs for PD-L1 is feasible,as demonstrated in the present investigation.