Evidence of an Autocrine Role for Leptin and Leptin Receptor in Human Breast Cancer

We studied potential associations between the expression of leptin, leptin receptor (LEPR) and clinicopathological parameters of breast cancel; and the correlation of leptin with human telomerase reverse transcriptase (hTERT) and cyclooxygenase 2 (COX2) Patients and Methods: A total of 153 specimens were studied. Transcript levels were determined using quantitative polymerase chain reaction (qPCR), and were correlated with clinicopathological data collected for over 10 years. Additionally, leptin and LEPR expression was studied in several breast cell lines. Results: Both leptin and LEPR mRNA expression were higher in malignant samples (p=0.0011 and 0.0014 respectively). Both were also expressed in MDA436 and MCF7 cell lines. Leptin showed a significant correlation with LEPR (r=0.504, p=0.0000000222). Leptin did not correlate significantly with clinical stage, tumour grade, or with the expression of hTERT or COX2. Conclusions: This study demonstrates that leptin and LEPR are more readily expressed in cancerous tissues suggesting a possible autocrine role in mammary carcinogenesis, which may be independent of hTERT and COX2 genes.