The roles of serum leptin concentration and polymorphism in leptin receptor gene at codon 109 in breast cancer

Aims: We investigated the relationship between serum leptin concentrations and polymorphism of the leptin receptor gene and breast cancer. Methods: Serum leptin concentrations were measured by enzyme-linked immunosorbent assay in 47 women with invasive breast cancer compared with 41 age-matched controls without cancer. Genomic DNA was extracted from peripheral blood leukocytes. Genotyping of the leptin receptor gene at codon 109 (LEPR-109) was performed by polymerase chain reaction-restriction fragment length polymorphism. Results: Patients with breast cancer had a higher mean serum leptin concentration than women in the control group, but the difference was not statistically significant. Among those with breast cancer, the serum leptin concentration was higher in women with highgrade cancers (p = 0.020). The LEPR-109RR genotype was more frequent in premenopausal patients with tumors larger than 2 cm (p = 0.039) and in premenopausal women who were overweight (p = 0.029). Among patients with the LEPR-109RR genotype, higher mean serum leptin concentrations were present in those with triple-negative cancers (p = 0.048). Conclusions: Our study suggests an association between serum leptin concentration and tumor progression. LEPR-109 polymorphism in premenopausal women appears to be associated with obesity and tumor progression. Copyright (c) 2007 S. Karger AG, Basel.