FKBP5 and cancer: Accordantly, FKBP5 that acts antagonistically to the function of FKBP4 (Barent et al, 1998; Davies et al, 2002; Galigniana et al, 2010) was found to confer chemosensitization via negatively regulating AKT in several types of cancer cells (Pei et al, 2009; Li et al, 2011).