Figure 3
ER/PR-negative breast cell tumor induction and growth are regulated by 5αP and 3αHP. (A) Tumor induction and growth are stimulated by 5αP. MDA-MB-231 cells were implanted in mammary fat pads of 11 mice (day 0, inset); 3 days before (day -3), five mice were injected with vehicle (control; black open circles), and six were injected with 5αP (red, solid circles). Data points represent size (mm3; mean ± SEM) of tumors that developed of a total number of mice per treatment (bracketed values), and the experiment was terminated on day 40. *Significantly different from controls at P < 0.05. (B) Tumor induction and growth are stimulated by 5αP and inhibited by 3αHP. Twenty-four mice were divided into four groups of six mice each, and MDA-MB-231 cells were implanted on day 0 (inset). Two days before (day -2) and on day 12, mice were injected with either vehicle (control; black open circles), 5αP (red, solid circles), 3αHP (blue inverted triangles), or 5αP+3αHP (green squares). The 5αP-treated mice were terminated on day 46 because of tumor burden, and the other mice were terminated on day 59. Data points represent size (mm3; mean ± SEM) of tumors that developed of a total number of mice per treatment (bracketed values). Significantly different from controls at *P < 0.05 and ***P < 0.001.