title: Inverse association of leptin levels with renal cell carcinoma: results from a case-control study.
abstract: OBJECTIVE
  Leptin is primarily produced in adipose tissue and appears to play a modulatory role between metabolism and immunity. Given that obesity, a state of chronic inflammation, is an established risk factor for Renal Cell Carcinoma (RCC), we investigated the association between plasma leptin levels and RCC risk.
  
  
  METHODS
  This case-control study included 70 patients with newly diagnosed, histologically confirmed RCC and 280 age-, gender- and district of residence-matched controls. Anthropometric data, socio-demographic variables, medical history, lifestyle habits and dietary data were derived from a personal interview. Serum leptin and adiponectin levels were determined using standard commercial kits. Adjusted odds ratios for RCC risk were derived through multiple logistic regression analyses.
  
  
  RESULTS
  Leptin levels were inversely associated with RCC risk (OR: 0.53, CI: 0.28- 0.99, p = 0.05), even after controlling for potential confounding factors, such as Body Mass Index (BMI), recent weight change, history of diabetes mellitus and other obesity related hormones, notably adiponectin.
  
  
  CONCLUSIONS
  The precise mechanism linking obesity with RCC remains unclear; however, the inverse association of leptin with RCC might be attributed, at least in part, to hormonal cross-talk with complex neuron-endocrine and immune circuits. These findings, if confirmed in prospective and interventional studies, might further elucidate the underlying mechanisms.
authors.affiliation: Department of Hygiene, Epidemiology and Medical Statistics, Athens University Medical School, Athens, Greece.
authors.forename: Themistoklis N
authors.initials: TN
authors.lastname: Spyridopoulos
authors.forename: Eleni Th
authors.initials: ET
authors.lastname: Petridou
authors.forename: Nick
authors.initials: N
authors.lastname: Dessypris
authors.forename: Agapios
authors.initials: A
authors.lastname: Terzidis
authors.forename: Alkistis
authors.initials: A
authors.lastname: Skalkidou
authors.forename: Charalambos
authors.initials: C
authors.lastname: Deliveliotis
authors.forename: George P
authors.initials: GP
authors.lastname: Chrousos
mesh_terms: D052242:Adiponectin / Q000097:blood; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002292:Carcinoma, Renal Cell / Q000097:blood* / Q000209:etiology; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000097:blood* / Q000209:etiology; D020738:Leptin / Q000097:blood*; D008297:Male; D008875:Middle Aged; D018570:Risk Assessment; D012307:Risk Factors
chemical_list: D052242:Adiponectin; D020738:Leptin