Tissue levels of adiponectin in breast cancer patients

Abstract

Adiponectin is a new adipocyte-secreted protein and associated with insulin-resistant status, such as type 2 diabetes mellitus and obesity. The inverse correlation between serum adiponectin levels and breast cancer risk was recently documented. On the other hand, the association of tissue adiponectin levels with breast cancer has not been previously reported. Thus, in the present study, the relationship between tissue adiponectin levels and breast cancer was evaluated. We analyzed the correlation between tissue adiponectin levels and the occurrence of breast cancer in a case-control study comprising 27 women with diagnosed and histologically confirmed breast cancer and 33 women with fibroadenoma. In addition, the association of tissue adiponectin levels with the various classical risk factors, such as body mass index, menopausal status and, tumor size, stage, lymph node status, hormonal status were also studied. Tissue adiponectin levels in patients with breast cancer (0.75 +/- 0.06) were significantly higher than those in controls (0.68 +/- 0.1) (P = 0.02). The high tissue adiponectin levels were associated with significantly (P = 0.001) an increased risk for breast cancer compared with those in the low tissue adiponectin levels (OR, 1.34; 95% CI, 1.12-1.84) in breast cancer patients. In addition, postmenopausal women with the high tissue adiponectin levels showed a significantly (P = 0.003) an increased risk for breast cancer compared with women in low tissue adiponectin levels (OR, 1.63; 95% CI, 1.23-1.90). The correlation between BMI and breast cancer was not found (P > 0.05). Furthermore, the status of estrogen receptor, progesterone receptor, HER-2/neu receptor and lymph nodes involvement were established, no effect on the tissue adiponectin levels in patients with breast cancer and no correlations were detected among tumor stage, tumor size and the levels of tissue adiponectin (P > 0.05). Our results suggest that the high tissue adiponectin levels significantly detected in breast cancer patients and associated with an increased risk for breast cancer.