title: Involvement of adiponectin in early stage of colorectal carcinogenesis.
abstract: BACKGROUND
  Although altered levels of adiponectin have been reported as a potential risk factor in colorectal cancer (CRC), the importance of the role played by adiponectin in colorectal carcinogenesis has not been established. We sought to examine the expression pattern of adiponectin and adiponectin receptors (AdipoRs) in the normal-adenoma-carcinoma sequence and to assess the implications of adiponectin in colorectal carcinogenesis.
  
  
  METHODS
  Serum adiponectin concentrations, and the mRNA and protein expression of adiponectin and AdipoRs were examined using serum and tissues from patients with CRC, advanced adenoma, and a normal colon. mRNA expression of AdipoRs and epithelial-mesenchymal transition regulators including E-cadherin, cyclooxygenase-2 (COX-2) and T-cadherin were examined in HCT116 cells treated with adiponectin.
  
  
  RESULTS
  Serum adiponectin concentrations in patients with advanced adenoma and CRC were lower than those in controls. Adiponectin mRNA was not detected in colonic tissue, whereas AdipoRs mRNA was lower in advanced adenoma and CRC than that in normal colon tissues. Immunohistochemical staining demonstrated that adiponectin was expressed in spindle-shaped cells of the subepithelial layer in normal colon tissues, whereas ill-defined overexpression of adiponectin was seen in the stroma of advanced adenoma and CRC tissues. AdipoRs expression was strong in normal epithelium, but weak to negative in the epithelia of CRC tissues. Adiponectin downregulated COX-2 mRNA expression in vitro, but upregulated T-cadherin in HCT116 cells.
  
  
  CONCLUSIONS
  Systemic adiponectin and local AdipoRs expression in the colon may be associated with anti-tumorigenesis during the early stages of CRC. These findings offer new insight into understanding the relationship between adiponectin and colorectal carcinogenesis.
authors.forename: Chung Hyun
authors.initials: CH
authors.lastname: Tae
authors.affiliation: Department of Internal Medicine, Ewha Medical Research Institute, Ewha Womans University School of Medicine, Seoul, Korea. kimse@ewha.ac.kr.
authors.forename: Seong-Eun
authors.initials: SE
authors.lastname: Kim
authors.forename: Sung-Ae
authors.initials: SA
authors.lastname: Jung
authors.forename: Yang-Hee
authors.initials: YH
authors.lastname: Joo
authors.forename: Ki-Nam
authors.initials: KN
authors.lastname: Shim
authors.forename: Hye-Kyung
authors.initials: HK
authors.lastname: Jung
authors.forename: Tae Hun
authors.initials: TH
authors.lastname: Kim
authors.forename: Min-Sun
authors.initials: MS
authors.lastname: Cho
authors.forename: Kwang Ho
authors.initials: KH
authors.lastname: Kim
authors.forename: Joung Sook
authors.initials: JS
authors.lastname: Kim
mesh_terms: D052242:Adiponectin / Q000097:blood / Q000235:genetics* / Q000378:metabolism; D000368:Aged; D015992:Body Mass Index; D015820:Cadherins / Q000235:genetics / Q000378:metabolism; D016022:Case-Control Studies; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D015179:Colorectal Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology*; D051546:Cyclooxygenase 2 / Q000235:genetics / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D054419:Receptors, Adiponectin / Q000235:genetics / Q000378:metabolism; D012307:Risk Factors
chemical_list: D052242:Adiponectin; D015820:Cadherins; C099972:H-cadherin; D054419:Receptors, Adiponectin; D051546:Cyclooxygenase 2