Expression And Significance Of Ku80、PDGFR-α And PD-L1in Nasal NK/T-cell Lymphoma

Objective:To detect the expression of Ku80, PDGFR-a, PD-L1and assess the relationship between the expression of above proteins in nasal NK/T cell lymphoma with their clinicopathological characteristics and prognostic significance. To explore their roles in generation and development of nasal NK/T cell lymphoma.The conclusion provides relevant basis for the clinical therapy of nasal NK/T cell lymphoma.Methods:Streptavidin-peroxidase immunohistochemistry was used to detect the expression of Ku80, PDGFR-a and PD-L1in35paraffin-embed samples of nasal NK/T cell lymphoma, and30paraffin-embed samples of benign lesion were also used for comparison. All cases of nasal NK/T cell lymphoma were followed-up. Statistical anaysis was performed using statistical software SPSS19.0. Rank sum test was used to compare the differential expression of Ku80, PDGFR-a and PD-L1in experimental and control groups. Variance analysis was used to compare expression of Ku80, PDGFR-a and PD-L1in clinical cases of nasal NK/T cell lymphoma. The correlation analysis was based on spearman correlation analysis. Survival curves were calculated according to Kaplan-Meier method. Multivariate analysis was based on COX regression model with P values lower than0.05considered as statistically significant. Results:The positive expression rate of Ku80, PDGFR-a and PD-L1in the group of nasal NK/T cell lymphoma was94.3%,91.4%and97.1%, respectively. The positive expression rate of Ku80, PDGFR-a and PD-L1in the control group was76.7%,80.0%and66.7%. The positive expression rates of Ku80, PDGFR-a and PD-L1between the group of nasal NK/T cell lymphoma and control group had statistical significance (P<0.05).1. The expression of Ku80showed a positive correlation with the expression of PDGFR-a in nasal NK/T cell lymphoma (r=0.496, P=0.002) but showed no correlation with that of PD-L1(r=0.103, P=0.555); The expression of PDGFR-a also had no correlation with the expression of PD-L1(r=-0.053, P=0.761).2. The expression of Ku80, PDGFR-a and PD-L1had no significant correlation with the gender, age, IPI score, B symptoms, the level of LDH and clinical stage of the patients who have been diagnosis is with nasal NK/T cell lymphoma (P>0.05).3. In all cases of patients, the median PFS (overall survival) was28months. IPI score:0-2, the median PFS was34months,3-4, the median PFS was25.6months and the difference was significant (P=0.01); Ann Arbor stage:the median PFS was35.7months and25.6months for stage of â… -â…¡ and â…¢-â…£, respectively and the difference was statistically significant (P=0.016); There is no statistically significant difference between the gender, age, B symptoms, the level of LDH of patients with PFS. The median PFS of the low-Ku80-expression group and high-Ku80-expression group was38.6months and29months, respectively, and the difference was significant (P=0.003); The median PFS of the low-PDGFR-a-expression group and high-PDGFR-a-expression group was38.5months and30.5months, respectively, and the difference was significant (P=0.034);The median PFS of the low-PD-L1-expression group and high-PD-L1-expression group was35.7months and32.6months, respectively. There is no statistical significance (P=0.089).4. A multivariate Cox regression model showed that IPI score of3-4, the high expression of Ku80and PDGFR-a were independent predictors of PFS with HR (hazard ratio) at7.308,11.495and4.836.Conclusion:1. The expression of Ku80, PDGFR-a and PD-L1in patients with nasal NK/T cell lymphoma is significantly higher compared with patients with benign lesions.2. High expression of Ku80, PDGFR-a and IPI score of3-4are independent predictive factors.