Study on application of human Dickkopf-1 prokaryotic expression products in serum of patients with non-small cell lung cancer

Objective To investigate the potential clinical value of Dickkopf-1 ( DKK 1 ) autoantibody in serum of patients with non small cell lung cancer (NSCLC). Methods DKK-1 cDNA was obtained by RT-PCR,prokaryotic expression vector pET30a ( + )/DKK-l was constructed,protein was purified by affinity chromalography. fractionated by sodium dodecyl sulfate polyacrylamide gel clectropheresis and appraised by Western blot. DKK-1 autoantibody in scrum of 38 healthy controls and 97 patients with NSCLC was detected by indirect enzyme linked immunosorbent assay. Results The positive rate of DKK-1 autoantibody in serum of patients with NSCLO was 34.0%. and the specificity was 84. 2%. DKK-1 autoantibody was correlated with distant metastasis of tumor in patients with NSCLC ( P = 0.006). The positive rate of carcinoembryonic antigen combined with DKK-1 autoantibody was significantly higher than that with other tumor markers including pro-gastrin releasing peptide,cytokeratin,neuron-specific enolase.and squamous cell carcinoma antigen. Conclusions In our research,the prokaryotic expression vector pET30a ( + )/DKK 1 is successfully constructed,and indirect enzyme linked immunosorbent assay is applied to detect DKK-1 autoantibody in serum of patients with NSCLC. DKK 1 autoantibody may become a useful tumor marker in the diagnosis and treatment of NSCLC. Key words: Prokaryotic expressions; DKK-1 autoantibody; Non-small cell lung cancer; Indirect enzyme linked immunosorbent assay