STUB1 and neoplasm: HOP (Hsp Organizing Protein) is a co-chaperone assisting in forming a complex between Hsp70 and Hsp90 [29, 30] whereas CHIP (Carboxyl-terminus of Hsp70-Interacting Protein) is an E3 ubiquitin ligase that regulates ubiquitination and subsequent protein degradation of chaperone clients and tumour-related proteins.