RAB9A and breast cancer: It was noted that XBP1 is highly expressed in dendritic cells (DCs) and is involved in NF-KB signaling, contributing to the IRE1α-XBP1-cMyc axis and the IRE1-XBP1 signaling pathway, and accelerating the expression of Rab9(a small GTPase) and NCOA3, which promotes proliferation, metastasis, and antimmune effects in breast cancer cells (Hu R. et al., 2015; Cubillos-Ruiz et al., 2015; Gupta et al., 2016; Liu Y. et al., 2019; Dong et al., 2019).