ERN1 and cancer: It is also plausible that the involvement and significance of the IRE1/XBP1s axis is cancer type-specific given that in breast cancer, the XBP1s were shown to interact with HIF-1α to cooperatively reprogram the cellular expression including the expression of glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA) [146,193,218].