DDIT3 and breast cancer: For instance, in prostate cancer cells, α-mangostin modulates the endoplasmic reticulum stress (ER) markers, protein kinase RNA-like endoplasmic reticulum kinase (PERK), inositol requiring enzyme (IRE1), and C/EBP homologous protein (CHOP) with the activation of caspase-3, whereas, in breast cancer cells, it activates caspase-8, caspase-9, and caspase-7.