Elovl6 is a poor prognostic predictor in breast cancer

Abstract

Elongation of long chain fatty acids family member 6 (Elovl6) has been demonstrated to be involved in insulin resistance, obesity and lipogenesis. In addition, it has been reported that the protein is upregulated in human hepatocellular carcinoma and is implicated in nonalcoholic steatohepatitis-associated liver carcinogenesis. Excess body weight has been associated with an increased risk of postmenopausal breast cancer and poor prognosis. However, the connection between Elovl6 expression and outcome of breast cancer remains uncertain. Therefore, the present study used immunohistochemical analysis to investigate the expression of Elovl6 in breast cancer tissues from patients who had undergone curative mastectomy. Out of a total of 70 patients, 37.1% of patients exhibited positive Elovl6 expression in breast cancer tissue, whilst 62.9% were considered as negative. Positive Elov16 expression correlated with positive lymph node involvement and shorter recurrence-free survival. However, Elovl6 expression had no association with primary tumor size, lymph node metastasis, stage, grade, estrogen receptor, progesterone receptor, HER2 and age. Therefore, positive Elovl6 expression is a poor prognostic factor in patients with breast cancer that have previously undergone surgery, and may function as a potential therapeutic approach in the future, particularly in the scope of obesity related disease.

Keywords: breast cancer; elongation of long-chain fatty acids family member 6; lipogenesis; obesity; prognosis.

Figure 1.

Representative examples of Elovl6 expression in human breast cancer. Left lane, intensity score 0; middle left lane, intensity score 1; middle right lane, intensity score 2; and right lane, intensity score 3. (A) Hematoxylin, (B) Elovl6 staining, and (C) negative control. Scale bars, 500 µm. Elov16, elongation of long-chain fatty acids family member 6.

Figure 2.

Histological detection of Elovl6 protein in breast cancer cells. Lower panel, hematoxylin; upper panel, Elovl6 stain. Scale bars, 500 µm (left) and 100 µm (right). Elov16, elongation of long-chain fatty acids family member 6.

Figure 3.

Survival in Elovl6(+) and Elovl6(−) breast cancer tissues as determined by Kaplan-Meier survival analysis. Elov16, elongation of long-chain fatty acids family member 6.