Clusterin as an anti-apoptotic cytoprotective chaperone protein upregulated in an adaptive cell survival manner that confers resistance to various cell death triggers, including hormone-, radiation-, and chemotherapy. In pre-clinical models, inhibition of clusterin expression using the second generation antisense OGX-011 can enhance cell death following treatment with androgen ablation, radiotherapy, and chemotherapy. In phase I clinical trials, OGX-011 has been well tolerated and a biologically effective dose has been identified in humans.