Hop (Hsp70/Hsp90 organising protein), also called stress-inducible protein 1, which interacts with HSP70 and HSP90 was overexpressed in human colonic carcinoma (22), invasive pancreatic cancer cell lines and malignant tissues of pancreatic cancer patients, and knockdown of Hop gene may decrease the invasiveness of pancreatic cancer cells, possibly by means of modulation of HSP90 activity (23). The gene discussed is HSP90AA1; the disease is colon carcinoma.