Correlation Between The Expression Of Immune Checkpoint CD47 Protein And Non-small Cell Lung Cancer

Objective This study detected the expression of CD47 protein in the pathological tissues of patients with non-small cell lung cancer,analyzed the relationship between the expression of CD47 protein and its clinicopathological characteristics,revealed the prognostic significance of CD47 protein in non-small cell lung cancer,preliminarily explored the correlation between CD47 and PD-L1,and judged whether CD47 was a potential target of PD-L1 combined immunotherapy.Methods 1.From January 1,2015 to October 1,2019,50 cancer tissue samples were collected from non-small cell lung cancer patients who received cancer resection in the Department of Cardiothoracic Surgery of Chaohu Hospital affiliated to Anhui Medical University,and confirmed by the Department of Postoperative Pathology,and the paracancerous tissues of 20 patients were collected at the same time.2.In this experiment,immunohistochemical staining was used to detect the expression of CD47 protein in 50 cases of non-small cell lung cancer and 20 cases of paracancerous tissues,and to compare the difference of CD47 expression between the two groups.3.Collect the complete clinicopathological data of 50 patients with non-small cell lung cancer,including age,sex,smoking history,clinical stage,pathological type,degree of differentiation,and lymph node metastasis.The patients were followed up to record the progress of the disease or the date of death.4.tatistical analysis: SPSS26.0 statistical software was used to statistically analyze the data of this study,and Chi-square test was used to analyze the difference between the expression of CD47 protein and clinical pathological characteristics.Kaplan-Meier method was used for survival analysis,and Log-rank test was used to analyze the expression of CD47 protein and the relationship between various clinicopathological characteristics and progression-free survival of patients,and the survival curve was drawn;COX proportional risk regression model was used for multifactor analysis.Use TCGA database to identify the association between CD47 and PD-L1.The difference between the results of each statistical analysis method is statistically significant(P<0.05).Result 1.The positive expression rate of CD47 was 52%(26/50)and the negative expression rate of CD47 was 48%(24/50)in 1.50 patients.In the tissues adjacent to cancer,the positive expression rate of CD47 was 20%(4/20),and the negative expression rate of CD47 was 80%(16/20).The positive expression rate of CD47 in NSCLC tissue was higher than that in adjacent tissues,and the difference was statistically significant(P<0.05).2.In 50 patients,the positive expression of CD47 protein was correlated with clinical stage and lymph node metastasis(P=0.043,P=0.010).The later the stage,the higher the probability of CD47 positive expression in patients with lymph node metastasis;The positive expression of CD47 was not correlated with age,sex,smoking history,pathological type and differentiation degree of patients(P>0.05).3.The progression-free survival time of CD47 positive expression group was significantly shorter than that of the negative expression group(P=0.003),suggesting that CD47 positive expression predicted poor prognosis of patients.In addition,patients with late clinical stage and lymph node metastasis had better prognosis(P<0.05);However,age,sex,smoking history,pathological type and degree of differentiation were not correlated with prognosis(P>0.05).Multivariate analysis was further carried out with COX proportional risk regression model.The expression level of CD47 protein and the correlation distribution between clinical stage and progression-free survival period were significantly different(P=0.000,P=0.047),while lymph node metastasis was not statistically significant with progression-free survival period(P>0.05).4.In non-cell lung cancer,the expression of CD47 and PD-L1 is positively correlated(P=5.3e-08,r=0.16).Conclusion 1.CD47 protein was up-regulated in non-small cell lung cancer,and the expression level of CD47 was related to the clinical stage and lymph node metastasis of patients.The positive expression rate of CD47 was higher in patients with late clinical stage and lymph node metastasis.2.The progression-free survival period of patients with CD47 positive expression is shortened,indicating poor prognosis.CD47 positive expression can be used as a biomarker of poor prognosis in NSCLC.3.There is a positive correlation between the expression of CD47 and PD-L1.CD47 can be a potential target for PD-L1 combined immunotherapy.