Nrdp1 expression to predict clinical outcome and efficacy of adjuvant anthracyclines-based chemotherapy in breast cancer: A retrospective study.

BACKGROUND

Existing reports showed loss of Nrdp1, an E3 ubiquitin ligase, promoted breast cancer malignancy because of failure to deregulate ErbB3. However, the correlation between Nrdp1 expression with clinical data is still unknown.

OBJECTIVE

We explored the predictive value of Nrdp1 regarding the clinical outcome of patients and the benefit of adjuvant anthracycline-based chemotherapy.

METHODS

113 primary breast cancer samples were obtained during surgery and the patients received average 10-year follow-up. We obtained Nrdp1 and ErbB3 expressions by immunohistochemistry.

RESULTS

Nrdp1 expression correlates with overall survival and disease-free survival of patients, with a hazard ratio of 0.237 (p=0.001) and 0.280 (p< 0.001) respectively. Additionally Nrdp1 correlates inversely with ErbB3 expression in tumor tissue (p=0.009). However the prognosis of Nrdp1 was not solely dependent on its regulation of ErbB3 degradation since there was also a significant correlation between Nrdp1 and overall survival (p=0.005) in ErbB3-negative patients. In patients who received anthracycline-based chemotherapy, low Nrdp1 expression indicated decreased disease-free survival (p=0.006) and high rates of metastasis and/or recurrence (p<0.001).

CONCLUSION

Nrdp1 may serve as a useful biomarker for the clinical outcome and efficacy of adjuvant anthracyclines-based chemotherapy in breast cancer.The prognosis of Nrdp1 was not solely dependent on its deregulation of ErbB3.