title: An inverse correlation between Interleukin-6 and select gene promoter methylation in patients with gastric cancer.
abstract: BACKGROUND
  Both serum IL-6 levels and CpG island methylation have been shown to have prognostic significance in gastric cancer, it was suggested that an important link existed between IL-6 and methylation of cancers.
  
  
  OBJECTIVE
  To investigate the prognostic value of IL-6 serum level and the association between serum IL-6 levels and CpG island methylation at p16, DAPK, MGMT and E-cadherin in patients with gastric cancer.
  
  
  METHODS
  Methylation status was assessed by MSP in 75 surgical specimens of gastric adenocarcinoma. IL-6 serum levels were measured by chemiluminescent enzyme immunoassay (CLEIA).
  
  
  RESULTS
  Methylation of p16, DAPK, MGMT, and E-cadherin were present in 53, 48, 32, and 59% of patients. Patients with tumors methylated at p16 and DAPK had lower serum levels of IL-6 compared to unmethylated tumors (1.8 vs. 4.8 pg/ml, p = 0.01 for p16; 1.5 vs. 6.2 pg/ml, p = 0.0001 for DAPK). But there was no difference with MGMT and E-cadherin methylation status. Serum IL-6 levels were also associated with TNM stage (p = 0.001), depth of tumor invasion (p = 0.002), lymphatic invasion (p = 0.01), vascular invasion (p = 0.008), metastasis (p = 0.002) and signet cell histology (p = 0.001).
  
  
  CONCLUSIONS
  IL-6 is of prognostic value for patients of gastric cancer. Low serum IL-6 levels were associated with p16 or DAPK gene methylation in patients with gastric cancer.
authors.affiliation: Department of Medicine, University of Hong Kong, Hong Kong, SAR, China.
authors.forename: Li Ping
authors.initials: LP
authors.lastname: Tang
authors.forename: Chi Hin
authors.initials: CH
authors.lastname: Cho
authors.forename: Wai Mo
authors.initials: WM
authors.lastname: Hui
authors.forename: Camy
authors.initials: C
authors.lastname: Huang
authors.forename: Kent Man
authors.initials: KM
authors.lastname: Chu
authors.forename: Harry H X
authors.initials: HH
authors.lastname: Xia
authors.forename: Shiu Kum
authors.initials: SK
authors.lastname: Lam
authors.forename: Asif
authors.initials: A
authors.lastname: Rashid
authors.forename: Benjamin C Y
authors.initials: BC
authors.lastname: Wong
authors.forename: Annie On On
authors.initials: AO
authors.lastname: Chan
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D051017:Apoptosis Regulatory Proteins / Q000235:genetics; D015820:Cadherins / Q000235:genetics; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000235:genetics; D018899:CpG Islands / Q000235:genetics; D019175:DNA Methylation; D015254:DNA Modification Methylases; D045643:DNA Repair Enzymes; D064550:Death-Associated Protein Kinases; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D016147:Genes, Tumor Suppressor; D019942:Genes, p16; D006801:Humans; D015850:Interleukin-6 / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis; D011401:Promoter Regions, Genetic / Q000235:genetics; D013274:Stomach Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D025803:Tumor Suppressor Protein p14ARF / Q000235:genetics; D025521:Tumor Suppressor Proteins
chemical_list: D051017:Apoptosis Regulatory Proteins; D015820:Cadherins; D015850:Interleukin-6; D025803:Tumor Suppressor Protein p14ARF; D025521:Tumor Suppressor Proteins; D015254:DNA Modification Methylases; C515491:MGMT protein, human; D064550:Death-Associated Protein Kinases; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D045643:DNA Repair Enzymes