title: Chemotherapy effectively suppresses interleukin-20, receptor activator of nuclear factor kappa-B ligand, and osteoprotegerin levels in patients with lung adenocarcinoma and bone metastasis.
abstract: 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.
  
  
  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.
authors.affiliation: Department of Traumatic Orthopedics, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, China.
authors.forename: Mingyang
authors.initials: M
authors.lastname: Yu
authors.affiliation: Department of Traumatic Orthopedics, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Su
authors.affiliation: Department of Traumatic Orthopedics, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, China.
authors.forename: Daping
authors.initials: D
authors.lastname: Cui
authors.affiliation: Department of Traumatic Orthopedics, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Sun
authors.affiliation: Department Chemistry, Stony Brook University, NY, USA.
authors.forename: Bowu
authors.initials: B
authors.lastname: Luan
authors.affiliation: Department of Orthopaedics, Affiliated Zhongshan Hospital of Dalian University, Dalian, Liaoning, China.
authors.forename: Dewei
authors.initials: D
authors.lastname: Zhao
mesh_terms: D000230:Adenocarcinoma / Q000097:blood* / Q000188:drug therapy / Q000473:pathology*; D000077192:Adenocarcinoma of Lung; D000328:Adult; D000368:Aged; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use; D015415:Biomarkers; D001859:Bone Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000556:secondary*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007378:Interleukins / Q000097:blood*; D008175:Lung Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D053244:Osteoprotegerin / Q000097:blood*; D053245:RANK Ligand / Q000097:blood*
chemical_list: D015415:Biomarkers; D007378:Interleukins; D053244:Osteoprotegerin; D053245:RANK Ligand; C422042:interleukin 20