Mn58b treatment slowed tumor growth through the inhibition of Akt(ser473) phosphorylation. A, Immunosuppressed mice were injected with MDA-MB 231 cells on each flank and tumors were allowed to grow to 0.1 cm3. At week 3.5, Mn58b or vehicle, were administrated to the mice intraperitoneally and the growth of tumor monitored. B, 11 xenografts excised from the mice treated with vehicle (C1-6) or Mn58b (T7-11) were frozen and lysed for western blot with the indicated antibodies or D, fixed in paraformaldehyde and section for immunohistochemistry staining with anti-total Akt and anti-pAkt(ser473). C, pAkt(ser473) signal was quantified with Image J program and normalized to total Akt. The ratios were input as scatter plot and analyzed using unpaired t-test with Prism (GraphPad). ** p < 0.05.