title: Serum leptin levels in gastric cancer patients and the relationship with insulin resistance.
abstract: BACKGROUND
  Serum leptin levels have been examined in various cancers, with conflicting results. However, there is limited information regarding serum leptin levels and insulin resistance in gastric cancer patients. Therefore, we aimed to investigate serum leptin levels, performance status, insulin levels and insulin resistance in patients with gastric cancer. In addition, we examined the relationship between these measurements and leptin levels.
  
  
  METHODS
  Thirty-nine patients with gastric cancer and 30 control subjects were enrolled in the study. Serum leptin, total protein, albumin, growth hormone, insulin and glucose levels were measured. The homeostasis model assessment (HOMA) was used to assess insulin resistance.
  
  
  RESULTS
  Serum levels of insulin, glucose and growth hormone and insulin resistance were significantly lower in gastric cancer patients than controls (p < 0.05 for all). In the Pearson correlation analysis, insulin resistance was found to be significantly correlated with serum leptin levels in gastric cancer patients (r = 0.320, p = 0.047). We observed a significant negative correlation between performance status and insulin resistance in patients with cachexia (r = -0.512, p = 0.030), while no association was found in non-cachectic patients.
  
  
  CONCLUSIONS
  We concluded that serum leptin levels are significantly lower in gastric cancer patients. In addition, gastric cancer patients have decreases in insulin levels, insulin resistance and growth hormone levels. This study found a positive association between serum leptin levels and insulin resistance. Moreover, there is a negative association between serum leptin levels and growth hormone levels. Thus, low insulin and growth hormone levels may suppress the production of leptin in gastric cancer patients.
authors.affiliation: Department of Internal Medicine, Medical Faculty, Yuzuncu Yil University, Van, Turkey.
authors.forename: Huseyin
authors.initials: H
authors.lastname: Begenik
authors.affiliation: Department of Internal Medicine, Medical Faculty, Yuzuncu Yil University, Van, Turkey.
authors.forename: Mehmet
authors.initials: M
authors.lastname: Aslan
authors.affiliation: Department of Gastroenterology, Medical Faculty, Yuzuncu Yil University, Van, Turkey.
authors.forename: Ahmet Cumhur
authors.initials: AC
authors.lastname: Dulger
authors.affiliation: Department of Internal Medicine, Medical Faculty, Yuzuncu Yil University, Van, Turkey.
authors.forename: Habib
authors.initials: H
authors.lastname: Emre
authors.affiliation: Department of Biochemistry, Medical Faculty, Istanbul University, Istanbul, Turkey.
authors.forename: Ahu
authors.initials: A
authors.lastname: Kemik
authors.affiliation: Department of General Surgery, Medical Faculty, Yuzuncu Yil University, Van, Turkey.
authors.forename: Ozgur
authors.initials: O
authors.lastname: Kemik
authors.affiliation: Department of Internal Medicine, Medical Faculty, Yuzuncu Yil University, Van, Turkey.
authors.forename: Ramazan
authors.initials: R
authors.lastname: Esen
keywords: gastric cancer; gender; growth hormone; insulin; insulin resistance; leptin