FEAT expression correlates with tumor size, PR status, HER2 expression, Ki67 index, and molecular subtype and predicts recurrence in breast cancer.

FEAT protein is uniformly overexpressed in a variety of human cancers but weakly expressed in normal tissue. FEAT has antiapoptotic activity and plays a role in carcinogenesis; however, the correlation between FEAT and clinicopathologic characteristics in cancer has not been reported. Our study explores the expression of FEAT protein and its clinicopathologic significance in breast cancer. We examined the expression of FEAT in tissues from 131 cases of breast cancer by immunohistochemistry and analyzed the correlation between FEAT expression and clinicopathologic parameters. The difference in FEAT expression between normal breast tissues and breast cancer tissues was also investigated. Finally, we analyzed the association between FEAT expression and disease-free survival or overall survival. Our data showed that FEAT was expressed in the cytoplasm. The expression of FEAT protein was significantly higher in breast cancer tissues than in normal breast tissues. Moreover, the expression of FEAT protein was higher in breast cancer with a larger tumor size (>2 cm), negative PR, positive HER2, or higher Ki67 index (≥14%) than in breast cancer with a smaller tumor size (≤2 cm), positive PR, negative HER2, or lower Ki67 index (<14%) (P<0.05). In addition, the expression of FEAT protein was associated with tumor size, PR status, HER2 expression, Ki67 index, and molecular subtype. Survival analysis showed that disease-free survival and overall survival were significantly shorter in breast cancer patients with high FEAT expression than in those with low expression of FEAT (P<0.05). COX regression analysis showed that FEAT was an independent prognostic factor for recurrence in breast cancer, but not for survival. In conclusion, FEAT may be a potential biomarker for recurrence of breast cancer.