To determine whether the ER stress pathway was involved in LCA-induced prostate cancer cell death, we determined the concentration- and time-dependent effects of LCA on p-JNK, JNK, p-eIF2α, eIF2α and CHOP protein levels, as well as on levels of BIM and PUMA in PC-3 and DU-145 cells exposed for 24 h to sub-cytotoxic (3 and 10 μM) and overtly cytotoxic (30 and 50 μM) concentrations of LCA. The gene discussed is MAPK8; the disease is prostate carcinoma.