RLIP76 expression as a prognostic marker of breast cancer

OBJECTIVE: RLIP (Ral-interacting protein)-76/RalBP11 (Ral-binding protein-1), a multifunctional protein and stress-inducible non-ABC transporter, have been proven to serve as a critical role in cancer development and progression; however, little is known about the pathological role of RLIP76 in breast cancer patients. The study aimed to determine the correlation between RLIP76 expression in breast cancer patient and clinical outcomes. PATIENTS AND METHODS: Using RT-PCR and Western blot, messenger RNA (mRNA) and protein expression of RLIP76 were determined in breast cancer and adjacent normal mammary tissues. The relationship of RLIP76 expression with clinical characteristics of 245 breast cancer patients was analyzed by immunohistochemistry. RESULTS: In the present study, our results indicated that RLIP76 mRNA and protein were highly expressed in the breast cancer tissues while compared with adjacent normal mammary tissues and the correlation with RLIP76 protein expression was significantly associated with age (the non-ABC transporter, stage and the expression were significantly associated-T2 vs. T3-T4, p < 0.01), lymph node metastasis (N0-N1 vs. N2-N3, p < 0.01), and PR (positive vs. negative, p < 0.01) in breast cancer patients; furthermore, we also found that RLIP76 protein overexpression was an unfavorable prognostic factor in the patients suffered from breast cancer. CONCLUSIONS: RLIP76 overexpression serves as an unfavorable prognostic biomarker in breast cancer patients.