ERN1 and plasma cell myeloma: A study by Wang et al. (2011) reported a paradoxical finding: in multiple myeloma cell lines, resveratrol activated the unfolded protein response (UPR) via the IRE1 signaling cascade, promoting XBP1 splicing, while simultaneously suppressing the activity of XBP1s as a transcriptional factor through SIRT1 [66].