In our study, xanthohumol in a concentration of 25 and after 2 and 8 h incubation of LNCaP cancer cells alone did not affect the expression of proapoptotic proteins Bid and Bax. TRAIL alone and TRAIL used with xanthohumol induced activation of Bid and led to a significant increase of the expression of Bax after 2 and 8 h incubation (the results are shown in Figure 6D,E), respectively. In this paper we have also demonstrated that TRAIL in combination with xanthohumol decreased the expression of anti-apoptotic protein Bcl-xL after 8 h incubation ( Figure 6F). The results are expressed as means˘SD obtained from three independent experiments. The β-actin was used as a control to show equal loading of proteins. The **data** were normalized to the control and β-actin level. A statistical significance of the differences between the treatment and control results is marked with * p < 0.05, ** p < 0.01, *** p < 0.001.