showed that selenomethyl selenocysteine, sodium selenite and methyl selenite could enhance the inhibitory effect of cyclophosphamide on canine breast cancer cells by down-regulating the expression of VEGF, angiotensin II (Ang II) and HIF-1α, which are related to the growth and vascularity of tumors, and by up-regulating the expression of phosphatase and tensin homologous genes (152). This evidence concerns the gene AGT and breast carcinoma.