Figure 7.
Breast cancer model. (A) Administration of doxorubicin resulted in a significant (p < 0.0001; 1-way ANOVA multiple comparison test) decline in body weights with or without ET supplementation relative to saline controls. ET-supplemented-animal weights remained similar to saline controls. (B) Cardiac function (LVEF) was measured at baseline and endpoint in the breast cancer model. As with the C57BL-6J doxorubicin model, a significant decrease in LVEF was seen with administration of doxorubicin relative to saline control animals. However, supplementation with ET significantly prevented this decline in cardiac function (2-way ANOVA with multiple comparison test; ** p < 0.01 vs. saline control # p < 0.05 vs. doxo + ET). The average volume (C) (estimated based on caliper measurements; Vol(mm3) = [width(mm)]2 x [length(mm)/2]) and weight (D) of the excised tumors are shown. Saline control animals had the largest tumor size, but administration of doxorubicin significantly decreased volume/weight of the tumor (* p < 0.05; 1-way ANOVA with multiple comparison test). Supplementation of animals with ET alone had a slight, but not significant, decrease in tumor size compared with saline controls. Likewise, ET supplementation in doxorubicin-treated animals had a slight but non-significant decrease in tumor size relative to doxorubicin alone. This indicates that ET does not aggravate tumor growth nor interfere with the chemotherapeutic effect of doxorubicin.