CLU and cancer: Because of the existence of ischemic and hypoxic microenvironment in cancer tissues, various kinds of molecular chaperones including heat shock protein 27 (Hsp 27)[7], Hsp90[8, 9], αB-crystallin[10], and clusterin (CLU)[11-14] are often adaptively overexpressed and closely related with the increased tumorigenicity, metastatic potential, and resistance to chemotherapy.