Our findings showed that BTCI treatment inhibited and/or unaltered expression of NF-kB target genes in a cell-type manner; whilst increasing expression of IL-8 in both cell lines.64,65 As a consequence of proteasome inhibition, a drop in cellular FLICE-inhibitory protein levels, which is a truncated and inactive form of caspase-8, has been reported in prostate cancer, renal cancer and leukemia.66,67 Given this, c-FLIP as a target for cancer therapy seems reasonable. This evidence concerns the gene CASP8 and prostate cancer.