Serological antibodies against LY6K as a diagnostic biomarker in esophageal squamous cell carcinoma

Objectives: To evaluate the diagnostic values of autoantibodies against lymphocyte antigen 6 complex locus K (LY6K) in esophageal squamous cell carcinoma (ESCC). Methods: After cloning, expressing, and purifying LY6K as fusion proteins, LY6K autoantibodies were measured in 62 patient and 58 control serum samples using enzyme-linked immunosorbent assay (ELISA). Reverse transcription polymerase chain reaction (RT-PCR) was used to measure the LY6K mRNA levels in ESCC and adjacent tissues. Results: LY6K autoantibodies were found significantly higher in patients than controls. The area under the receiveroperating characteristic (ROC) curve (AUC) was 0.85, and the optimal sensitivity and specificity for ESCC detection were 80.6 and 78.7%, respectively. LY6K mRNA expressions in patients were upregulated. Conclusions: Autoantibodies against LY6K may be a good diagnostic biomarker for ESCC.