MDM2 and cancer: There is now emerging evidence that gp96, as a pro-oncogenic chaperon for multiple onco-proteins, such as HER2 [9–11], the Wnt coreceptor LRP6 [19,20], integrin [5], toll like receptors [21], p53/Mdm2 [22], plays important roles in regulation of cancer initiation, progression and metastasis.