XBP1 and triple-negative breast carcinoma: Triple-negative breast cancer remains a disease that is resistant to many current therapies.4,5 The ability of a certain population of this MDA-MB-231 cell line to strongly upregulate the survival mechanisms of the UPR (XBP1) and display autophagy in the presence of strong transcriptional apoptotic induction in a larger population of this cell line may speak to a possible explanation for the virulence of this disease.