Expression Of PD-1 In Different EGFR Mutations And The Correlation To Prognosis And Clinicopathological Characteristics Of NSCLC

Objective:To investigate the expression of PD-1 protein in different EGFR mutations of human non-small cell lung cancer,and to study their relationship with the invasion,metastasis and prognosis.Methods:Immunohistochemistry method was applied to detect the expression of PD-1 protein in non-small cell lung cancer(n=88)and the adjacent normal tissues(n=88).Using PC RARMS sequencing assay samples to ensure EGFR mutation subtypes.The results were compared to clinical pathological factors.Univariable survival analysis and COX regression were used to predict prognosis.Results:(1)In non-small cell lung cancer and adjacent normal tissue the positive expression rate of PD-1 protein was 63.64% and 21.59% respectively.There was significant difference between the two groups(P <0.01).The expression of PD-1 was significantly correlated with lymph node metastasis and smoking(P <0.05).No association was observed with the age,gender,tumor size,the degree of differentiation,depth invasion and TNM stages(P>0.05).(2)EGFR mutations were 43 and 45 were wild-types.The mutation rate was 48.86%.The expression of PD-1 in lung cancer was no significant difference in EGFR mutation subtypes.(P> 0.05)(3)All 43 EGFR mutations included 24 cases of 19 Del exon mutation and 19 cases of 21L858 R mutation.The expression rate of PD-1 in different mutations were 83.33% and 52.63%.Anlyse showed the expression of PD-1 in different EGFR mutations was significantly correlated(P <0.05).Survival analysis showed that the survival time of PD-1 in EGFR wild-type was significantly different(P <0.05).There was no significant difference in the expression of PD-1 in EGFR mutation(P> 0.05).Conclusion:(1)The expression of PD-1 protein was related to the proliferation and invasion of lung cancer.(2)PD-1 was a risk factor for predicting the survival time of lung cancer patients.The expression of PD-1 was different in mutation types and wild-types of non-small cell lung cancer EGFR mutations.It provided evidence to prove that EGFR mutation 19 Del and 21L858 R was two different types of lung cancer.