Figure 1. Effect of calcitriol, soy, and their combination on PC-3 xenograft growth.

Human PC-3 cells were established in the flanks of male nude mice and allowed to grow for three weeks to approximately 100 mm³ before initiation of treatment (arrow). Treatment groups received either i.p. injections of 0.1 µg calcitriol in 50 µl of 0.1% ethanol in sterile saline every other day; soy-supplemented diet with 10 kcal% soy protein (10%-soy); soy supplemented diet with 20 kcal% soy protein (20%-soy); or a combination of calcitriol injections and soy-supplemented diets. Animals in the control group received i.p. injections of 0.1% ethanol in sterile saline every other day. Tumor volumes were measured weekly over the course of the four-week treatment period. Values represent mean ± SE. Control group n = 14; calcitriol group n = 16; 10%-soy group n = 13; 20%-soy group n = 14; 10%-soy+cal group n = 14; 20%-soy+cal group n = 12. * p < 0.05, ** p < 0.01 compared to control. + p < 0.05 compared to calcitriol. ^ p < 0.05 compared to 20%-soy. § Does not include animals that died before end of treatment course.