1.Anticarin-β shows a promising anti-osteosarcoma effect by specifically inhibiting CCT4 to impair proteostasis.
Gan WANG ; Min ZHANG ; Ping MENG ; Chengbo LONG ; Xiaodong LUO ; Xingwei YANG ; Yunfei WANG ; Zhiye ZHANG ; James MWANGI ; Peter Muiruri KAMAU ; Zhi DAI ; Zunfu KE ; Yi ZHANG ; Wenlin CHEN ; Xudong ZHAO ; Fei GE ; Qiumin LV ; Mingqiang RONG ; Dongsheng LI ; Yang JIN ; Xia SHENG ; Ren LAI
Acta Pharmaceutica Sinica B 2022;12(5):2268-2279
Unlike healthy, non-transformed cells, the proteostasis network of cancer cells is taxed to produce proteins involved in tumor development. Cancer cells have a higher dependency on molecular chaperones to maintain proteostasis. The chaperonin T-complex protein ring complex (TRiC) contains eight paralogous subunits (CCT1-8), and assists the folding of as many as 10% of cytosolic proteome. TRiC is essential for the progression of some cancers, but the roles of TRiC subunits in osteosarcoma remain to be explored. Here, we show that CCT4/TRiC is significantly correlated in human osteosarcoma, and plays a critical role in osteosarcoma cell survival. We identify a compound anticarin-β that can specifically bind to and inhibit CCT4. Anticarin-β shows higher selectivity in cancer cells than in normal cells. Mechanistically, anticarin-β potently impedes CCT4-mediated STAT3 maturation. Anticarin-β displays remarkable antitumor efficacy in orthotopic and patient-derived xenograft models of osteosarcoma. Collectively, our data uncover a key role of CCT4 in osteosarcoma, and propose a promising treatment strategy for osteosarcoma by disrupting CCT4 and proteostasis.