CDC37 and gastrointestinal stromal tumor: CDC37 phosphorylation is a requisite for CDC37 recruitment of kinase clients to the HSP90 complex.46 Therefore, targeting CK2 might inhibit KIT-directed HSP90 functions in GIST, and co-targeting of CK2 and KIT could exhibit greater anti-proliferative and pro-apoptotic effects in GISTs than either intervention alone.