Chemotherapy effectively suppresses interleukin-20, receptor activator of nuclear factor kappa-B ligand, and osteoprotegerin levels in patients with lung adenocarcinoma and bone metastasis.

BACKGROUND: Bone metastasis (BM) is common in patients with lung cancer. Osteolysis is caused by increased osteoclast activity. Interleukin-20 (IL-20) and receptor activator of nuclear factor kappa-B ligand (RANKL) are crucial for osteoclast formation. Osteoprotegerin (OPG) inhibits a receptor activator of RANKL/RANK signaling. The aims of this study were to analyze the serum levels of IL-20, OPG, and RANKL in patients with and without BM and to observe the effect of chemotherapy on these cytokines.

PATIENTS AND METHODS: A total 54 cases of pathologically confirmed lung adenocarcinoma (ADC) and 18 healthy individuals (Control) were enrolled in this study. Eligible patients were divided into three groups (18 patients per group): ADC without BM (ADC), ADC with BM (ADC + BM), and ADC with BM treated with chemotherapy (ADC + BM + Chemo). Serum IL-20, RANKL, and OPG levels were analyzed by enzyme-linked immunosorbent assay.

RESULTS: Serum IL-20, RANKL, and OPG levels in ADC + BM patients were significantly elevated compared with that in the Control or ADC groups (both P < 0.001). The serum cytokine levels were significantly lower following chemotherapy compared with that in patients who did not receive chemotherapy (P < 0.001).

CONCLUSIONS: Serum IL-20, RANKL, and OPG levels increase in patients with lung cancer and BMs. Chemotherapy suppresses the elevation of these cytokines.