Association of FOXA1 and EMT markers (Twist1 and E-cadherin) in breast cancer.

The transcription factor FOXA1 (forkhead box A1) plays key roles in tumor development and progression. In the present study, we analyzed the expression of FOXA1 in 52 breast tumors and 10 normal tissues, and investigated the relationship between FOXA1 and two EMT markers, namely Twist1 and E-cadherin by RT-PCR and IHC respectively. The expression level of FOXA1 was higher in tumor compared to normal tissues but the difference was not statistically significant (P = 0.138). FOXA1 expression correlated with less aggressive behavior as SBR grade I (P = 0.04), small tumors size (P = 0.05), and longer survival (P = 0.001). Furthermore, estrogen and progesterone positive tumors exhibit high level of FOXA1 (P = 0.002 and P = 0.038 respectively). Survival analysis showed that patients with ER positive/FOXA1 positive (P log rank = 0.001), PR positive/FOXA1 positive (P log rank = 0.044) and HER-2 negative/FOXA1 positive (P log rank = 0.002) tumors have a significant prolonged overall survival. On the other hand, the expression of E-cadherin positively correlated with FOXA1 (P = 0.028), whereas negative association was seen between the expression of Twist1 and FOXA1 (P = 0.016). Kaplan-Meier plots showed that patients with Twist1negative/FOXA1positive tumors have a significant prolonged overall survival (P log rank = 0.001) and FOXA1 appeared as independent predictors of patient survival in multivariate analyses. Overall, our results indicate that FOXA1 could be a useful biomarker to predict prognosis in breast cancer patients.