Neoadjuvant Chemotherapy Affects TFF3 Peptide Expression in Luminal B Subtype of Breast Cancer – A Pilot Study

Aim: Trefoil factor family 3 (TFF3) peptide is normally expressed by epithelial cells in breast ducts, but it is also associated with different pathological conditions, including breast cancer. It is considered a marker of poor prognosis and associated with increased resistance to chemotherapy. Data on the effect of chemotherapy on TFF3 peptide expression are scarce. The aim of this pilot study was to assess suitability of research on this topic for large-scale studies. Methods: Formalin-fixed, paraffin-embedded samples of core biopsies and of surgically removed tumors from patients with luminal B subtype of breast cancer were used for immunohistochemical analysis. Changes in TFF3 peptide and Ki-67 expression and microvessel density (MVD) values before and after chemotherapy were analyzed, as well as the association between TFF3 peptide expression and Ki-67 expression and MVD values. Results: Significant reduction in TFF3 and Ki 67 expression was observed after chemotherapy, while MVD values did not differ significantly before and after chemotherapy. The association of TFF3 peptide expression and Ki-67 expression and TFF3 peptide expression and MVD values was not significant before or after chemotherapy. Conclusion: The data obtained in this pilot study suggest that a large-scale study is justified, and that other breast cancer subtypes should be included.