CDK4 and colon adenocarcinoma: Known Hsp90 clients EGFR, HER2, CDK4, CDK6, CXCR4, Akt-1, c-Raf, Survivin, ERK-5 and Integrin α2 were analyzed following the administration of KUNB31 to HT29 (colon adenocarcinoma grade II) cells.