Serum expression of DKK1 protein in patients with non-small cell lung cancer and its relationship with osseous metastasis

Abstract

Objective To explore the serum expression of DKK1 protein, a Wnt signaling pathway inhibitor in patients with non-small cell lung cancer(NSCLC) and its relationship with osseous metastasis. Methods Serum DKK1 protein levels were assayed by enzyme-linked immunosorbent assay (ELISA) in NSCLC patients, including 33 NSCLC patients with osseous metastasis and 41 NSCLC patients without respectively, and 32 healthy volunteers were served as the control group. Furthermore, the differential expression of the serum DKK1 protein level between the patients and the volunteers was compared by using the variance analysis and the independent sample t test. The correlation between DKK1 expression and bone metastasis was detected by Pearson correlation analysis. Results Serum DKK1 protein level of NSCLC patients was (79.6±8.3) ng/ml, which was significantly higher than that in healthy volunteers [(21.5±6.4) ng/ml, t= 13.17, P= 0.001]. The serum DKK1 level in osseous metastasis group was (110.3±11.4) ng/ml, which was significantly higher than that in non-skeletal metastasis group [(60.7±10.5) ng/ml, t= 14.128, P= 0.003]. The positive association was observed between the DKK1 level in the peripheral blood and osseous metastasis in NSCLC patients (r= 0.855, P < 0.001). Conclusion The serum expression level of DKK1 protein in NSCLC patients is closely related to the osseous metastasis, which may be a predicting biomarker for the osseous metastasis. Key words: Lung neoplasms; Neoplasm metastasis; Enzyme-linked immunosorbent assay; DKK1 protein