Abstract 2237: Expression of the trefoil protein TFF3 in human breast cancers

Abstract

Abstract Expression of the trefoil protein TFF3 in human breast cancers The purpose of this study is to investigate expression of the trefoil factor family protein, TFF3 in a large series of human breast cancers. Trefoil factors are small secreted proteins that are expressed in mucus secreting epithelia. They are involved in mucosal protection in part by stimulation of cell motility. It has been proposed that the motogenic actions of trefoil proteins may facilitate tumor cell invasion and metastasis. Expression of TFF3 mRNA is regulated by estrogen in human breast cancer cell lines and strong association between estrogen receptor and TFF3 mRNA expression has been demonstrated in breast tumors by expression microarray analyses. A tissue microarray was constructed from 300 primary breast tumors and 76 metastatic deposits of breast tumors from patients who presented in the northern region of England between 2002 and 2003. TFF3 expression was evaluated by immunohistochemistry with an antibody raised against correctly-folded human TFF3 protein. Each sample was analyzed in duplicate. The intensity of the immunoreactions in 1,000 tumor cells was evaluated as: absent, weak, moderate or strong. The association of TFF3 expression with various clinico-pathological features and with estrogen receptor protein expression was tested statistically with SPSS software (p<0.01). Clear TFF3 expression is demonstrated in normal and malignant breast epithelial cells. There is no expression in stromal, endothelial or immune cells. Expression of TFF3 varied enormously between tumor samples. TFF3 expression is highest in mucinous and tubular breast adenocarcinomas. TFF3 is expressed at higher levels in lobular than in ductal breast cancers. TFF3 expression is associated strongly with estrogen receptor expression. There is a negative association between TFF3 expression and tumor grade. There is however a positive association between TFF3 expression and presence of vascular invasion and TFF3 expression is higher in metastatic breast tumor cells than in primary breast tumor cells. This is the first report of TFF3 protein expression in a large series of human breast tumors. The strong association between TFF3 and estrogen receptor suggests that TFF3 expression is dependent on estrogen in a significant proportion of breast tumors. The high expression of TFF3 in breast tumors with vascular invasion and in metastatic breast tumor cells supports the hypothesis that TFF3 predisposes towards breast cancer cell invasion. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2237.