Leptin and leptin receptor involvement in cancer development: a study on human primary breast carcinoma.
Obesity is associated with an increased risk of breast cancer. Leptin, a hormone synthesised essentially by adipose tissue, may be involved in cancer development. We examined the expression of leptin and leptin receptor (Ob-R) in human primary breast cancer and adjacent non-cancerous tissue. We also analysed their relationships with histological variables such as the oestrogen and progesterone receptors, Ki67 proliferation factor and tumour size. The expressions of leptin and Ob-R were investigated by immunohistochemical staining in 35 primary breast cancers and 17 adjacent non-cancerous tissues. Samples and histological features were obtained from the Anti-Cancer Centre. Expressions of leptin and Ob-R were detected in, respectively, 85 and 75% of the primary breast cancer cases studied. The expression of leptin was significantly correlated with Ob-R detection (p=0.008). In addition, Ob-R expression in primary breast carcinoma was positively correlated with oestrogen receptor expression (p=0.028) and tumour size (p=0.045) but not with Ki67 or progesterone receptor expressions. However, the expression of leptin showed no statistical correlation with these variables. First, the co-expression of leptin and Ob-R in primary breast cancer shows that leptin acts on mammary tumour cells via an autocrine pathway. Second, the co-expression of Ob-R and oestrogen receptors suggests a possible interaction between leptin and oestrogen systems to promote breast carcinogenesis. Finally, the fact that Ob-R expression was positively correlated with tumour size may point to a potential role of leptin as a growth factor and of Ob-R as a new prognostic factor.
Jardé
Thierry
T
UFR Pharmacie, Université Clermont 1, EA2416, France. thierry.jarde@u-clermont1.fr
Caldefie-Chézet
Florence
F
Damez
Mireille
M
Mishellany
Florence
F
Penault-Llorca
Frédérique
F
Guillot
Jean
J
Vasson
Marie Paule
MP
D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000737:chemistry / Q000209:etiology* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D020738:Leptin / Q000032:analysis / Q000502:physiology*; D008875:Middle Aged; D054411:Receptors, Leptin / Q000032:analysis / Q000502:physiology*
D020738:Leptin; D054411:Receptors, Leptin