Association of toll-like receptor 9 expression with prognosis in breast carcinoma

Aim: Breast cancer (BC) is a common malignancy in women. Some molecules including TLR9 are still under investigation as potential prognostic factors in BC. In the present study, we aimed to determine the relation between TLR9 expression and clinicopathological prognostic parameters and survival in BC. Materials and methods: One hundred and thirty nine patients diagnosed as BC included the present study. Immuno-reactivity scoring (IRS) system was used to reveal the tissue TLR9 expression levels. Results: We found higher TLR9 expression in tumors diagnosed as invasive carcinoma NOS, grade 3 tumors, tumors with necrosis, ER negative and Her2 positive tumors and tripple negative molecular subtype. Furthermore, tumors with low TLR9 scores showed increased overall survival compared to tumors with high TLR9 scores. Conclusions: TLR9 overexpression in BC is associated with some prognostic parameters including histologic type, tumor grade, tumor necrosis, ER and Her2 status and molecular subtype as well as overall survival. Further studies with larger patient series are needed to shed light on the use of TLR9 as a clinical and therapeutic target in BC.