(A) Immunohistochemical staining for GRP78 was strong in chemo-resistant tissues and weak in chemo-sensitive TNBC tissues. (B) The optical density of GRP78 was higher in chemo-resistant TNBC tissues than in chemo-sensitive ones (P<0.05). (C) A high GRP78 expression was associated with shorter disease-free survival (DFS), and a low GRP78 expression was associated with longer disease-free survival (log-rank P=0.0135). (D) Low GRP78 expression was associated with prolonged overall survival (OS) (log-rank P=0.0185). (E) RT-qPCR showed that miR-495-3p expression was lower in chemo-resistant tissues than in chemo-sensitive tissues (P<0.05). (F) High miR-495-3p expression correlated with longer overall survival for patients with breast cancer in the METABRIC database (log-rank P<0.001).