Clinical Role of ABCF2 Expression in Breast Cancer

Abstract

Background: The ATP binding cassette (ABC) family acts as efflux pumps and some members are related to chemoresistance in breast cancer. The clinical role of ABCF2 expression, a member of the ABC family, was analyzed. Materials and Methods: One hundred and ninety-one patients with breast cancer were enrolled. The median follow-up term was 76 months. ABCF2 expression was examined by immunohistochemistry. Results: Ninety percent of the breast cancer cases displayed immunoreactivity for ABCF2. The positive rate of ABCF2 expression was 63%. ABCF2 had a negative relationship to distant metastasis. ABCF2-positive tumors had longer disease-free survival (DFS) than -negative tumors in patients with lymph node metastasis (p=0.001). In patients treated with endocrine therapy, ABCF2-positive tumors had a longer DFS when the tumors were estrogen receptor-negative or progesterone receptor-negative (p=0.0019 and 0.005, respectively). Conclusion: ABCF2 was initially thought to be related to drug resistance. ABCF2 may play a role in tumor suppression at metastatic sites and in the endocrine pathway for breast cancer.