Blood Autoantibodies Anti-XAGE3 And Anti-DNAJC12 Can Be Used As Biomarkers To Predict The Curative Efficacy Of PD-1/PD-L1 Inhibitor In Patients With Advanced NSCLC

Objective: To explore the autoantibody index with high diagnostic accuracy and more suitable for Chinese lung cancer population.To explore the correlation between the expression of these serum autoantibodies and the therapeutic efficacy of PD-1/PD-L1 inhibitors,the aim is to explore the predictive markers of PD-1/PD-L1 inhibitors based on liquid biopsy and targeted at autoantibodies,and to provide new ideas for the discovery of new markers in view of the current lack of effective PD-1/PD-L1 efficacy prediction and monitoring markers.Methods: First,the largest human whole protein chip(containing～20000recombinant proteins,covering～75% of the human proteome)was used to screen tumor related antigens that can specifically bind to Ig G/Ig M and meet screening criteria from the plasma of 33 patients with different types of lung cancer,8 healthy individuals,and 22 patients with other lung diseases other than lung cancer.Then,gene cloning and expression methods were used to screen and prepare the above tumor related antigens.The obtained antigen was coated on the polystyrene bottom surface of the microporous plate by a solid phase coating method.Collect 49 patients with different types of lung cancer,33 healthy people,and 17 patients with other lung diseases other than lung cancer.Use "enzyme linked immunosorbent assay ELISA" to verify the selected autoantibodies.Finally,132 blood samples from patients with advanced NSCLC were collected,and the correlation between the expression of serum autoantibodies and the therapeutic efficacy of PD-1/PD-L1 inhibitors was explored using enzyme linked immunosorbent assay(ELISA).Results: Through protein chip technology,56 tumor related antigens that can specifically bind to Ig G/Ig M were screened and obtained.According to screening conditions and bioinformatics analysis,two candidate tumor antigens XAGE3(X antigen family protein 3)and DNAJC12(DNAJ heat shock family protein C12)were finally established.Tumor related antigens of XAGE3 and DNAJC12 were prepared by gene cloning and screening,and coated on the polystyrene bottom surface of the microporous plate.Elisa’s results showed that the AUC(95% CI)of anti DNAJC12(sensitivity 0.49,specificity 0.94)was 0.732(0.632-0.831),while the AUC(95% CI)of anti XAGE3(sensitivity 0.796,specificity 0.88)was 0.902(0.845-0.958),which was compared with the AUC(95% CI)of one of the currently recognized autoantibodies for lung cancer,NY-ESO-1(sensitivity 0.714,specificity 0.54),which was 0.601(0.478-0.715).It was found that the sensitivity and specificity of the combined detection of anti DNAJC12 and anti XAGE3(without Anti NY-ESO-1)autoantibodies were significantly improved(sensitivity 0.755,specificity 0.96),with an AUC(95% CI)of 0.923(0.873-0.972).When jointly detecting three autoantibodies,the sensitivity and specificity of anti DNAJC12,anti XAGE3,and anti NY-ESO-1 were the best(sensitivity 0.816,specificity 0.90),with an AUC(95% CI)of 0.924(0.876 to 0.973).In addition,the expression levels of the two types of autoantibodies screened from lung cancer are higher than those in the non lung cancer group.The above results demonstrate that the two types of autoantibodies in the peripheral blood of lung cancer can be used for the diagnosis and concomitant diagnosis of lung cancer.Finally,"Enzyme linked immunosorbent assay(ELISA)" was used to explore the correlation between the expression of serum autoantibodies and the therapeutic efficacy of PD-1/PD-L1 inhibitors in 132 patients with advanced NSCLC.Based on the follow-up information of 50 patients completed so far and the changes in the content of anti DNAJC12 and anti XAGE3 autoantibodies before and after immunotherapy,it is shown that serum autoantibodies anti XAGE3 and anti DNAJC12 have a certain predictive effect on the efficacy of PD-1/PD-L1 antibodies in patients with advanced NSCLC.Conclusion: The combined detection of anti DNAJC12,anti XAGE3,and anti NY-ESO-1 autoantibodies significantly improves the sensitivity and specificity,and can be used for the diagnosis and concomitant diagnosis of lung cancer.Anti DNAJC12 and anti XAGE3 can predict the efficacy of PD-1/PD-L1 antibodies in patients with advanced NSCLC.