High expression of Wilms' tumor suppressor gene predicts poor prognosis in breast cancer patients.

PURPOSE The prognostic significance of the Wilms' tumor suppressor gene(WT1) mRNA expression was evaluated in patients with invasive breast cancer. EXPERIMENTAL DESIGN WT1 mRNA expression in tumor tissues (n = 99) was examined by a quantitative, real-time PCR assay. RESULTS No significant association was observed between WT1 mRNA levels and clinicopathological parameters such as menopausal status, tumor size, lymph node status, histological grade, and estrogen receptor status. Five-year disease-free survival rate of patients with high WT1 mRNA levels (62.6%) was significantly (P < 0.05) poorer than those with low WT1 mRNA levels (77.2%). Lymph node metastasis (P < 0.05), high histological grade (P < 0.01), and estrogen receptor negativity (P < 0.05) were also significantly associated with poor prognosis, respectively. Multivariate analysis revealed that WT1 mRNA levels were a significant prognostic factor, independent of the other conventional prognostic factors. CONCLUSIONS These results suggest that measurement of WT1 mRNA levels in tumor tissues might be useful as a new prognostic factor in breast cancer patients.