Human breast carcinoma cell lines MCF-7 and MDA-MB-231, Breast cancer tissues and the matched normal tissues
SPRY4-IT1 was significantly more expressed in cancer tissues than in normal tissues (P<0.05). Increased SPRY4-IT1 expression was significantly correlated with increased rates of lymph node metastasis (P=0.002) and recurrence (P=0.017). Both were independent factors of SPRY4-IT1 expression (P<0.05). High-SPRY4-IT1 patients had significantly lower overall survival and disease-free survival. High SPRY4-IT1 expression indicated poor clinical response in the whole group, luminal A subgroup and luminal B subgroup (P<0.05) and pathological complete response in the whole group. Overexpression of SPRY4-IT1 promoted chemo-resistance of MCF-7 and MDA-MB-231 cells to epirubicin. SPRY4-IT1 has the potential to be a biomarker to predict NACT efficacy and prognosis in breast cancer patients.