Al-Salam S, et al. - A total of 133 cases of breast carcinoma treated with neo-adjuvant therapy were analyzed to understand the role of trefoil factor 3 (TFF3) in breast cancer chemoresistance and to establish TFF3 expression as a biomarker for drug resistance. For TFF3, Bcl2 (B cell lymphoma-2), BAX, cleaved caspase-3, AKT-1 (RAC-alpha serine/threonine-protein kinase), NF kappa B (Nuclear factor kappa B) and Ki-67, tissue samples from pre-neoadjuvant therapy as well as tissues from post-neo-adjuvant therapy of those cases were collected and stained with immunohistochemistry. Findings revealed a significant association of TFF3 expression with residual breast carcinoma following neoadjuvant chemotherapy. This implied an association between the expression of TFF3 and increased resistance to chemotherapy. Furthermore, the presence of its co-expression with antiapoptotic proteins; BCl2, AKT1 and NF Kappa-B in residual breast carcinoma cells and very low proliferating index and apoptotic bodies in residual tumors also supported the former finding.