To evaluate the potential regulation of the expression and activation of IGF-IR and downstream signaling mediators by vorinostat in endometrial cancer, Ishikawa and USPC-2 cells were treated with vorinostat for 24 h, in the presence or absence of IGF-I during the last 10 min of the incubation period (Figure 1). Here, IGF1R is linked to endometrial cancer.