Our findings show for the first time that human primary breast tumours and associated lymph node metastases exhibit a strong correlation between SK1 and leptin receptor expression (Pearson R = 0.78 and R = 0.77, respectively, P <0.001).
The association between both intratumoral Lep-R(L) and Lep-R(S) mRNA high tumors and a poor prognosis in the presence of high serum leptin or high intratumoral leptin mRNA levels seems to suggest that the leptin and Lep-R(L)/Lep-R(S) pathways are implicated in the growth stimulation of breast tumors.
To gain insight into the mechanism(s) by which leptin contributes to mammary tumor (MT) development we investigated the effects of leptin, kinase inhibitors, and/or leptin receptor antagonists (LPrA2) on 4T1 mouse mammary cancer cells in vitro and LPrA2 on 4T1-MT development in vivo.