Effect of down regulation of SPAG9 expression in breast cancer xenograft model. (a) A representative photomicrograph showing nude mice with tumor (arrows) treated with control siRNA or SPAG9 siRNA plasmid. (b) a graph representing tumor volume calculated on the indicated days revealed significant reduction in the tumor growth in mice treated with SPAG9 siRNA plasmid compared with control siRNA (n = 8; *, P < 0.0001). (c) Immunohistochemical analysis of proliferating cell nuclear antigen (PCNA) and SPAG9 protein in control siRNA and SPAG9 siRNA treated tumors. Left panel- hematoxylin and eosin staining showing the histological cytostructure of the tumor of the control siRNA and SPAG9 siRNA treated mice. Middle panel- shows the reduced SPAG9 expression probed with anti SPAG9 antibody in SPAG9 siRNA treated mice tumors compared with control siRNA treated mice. Right panel- similarly shows the reduced PCNA expression in the SPAG9 siRNA treated mice compared with control siRNA treated mice. (d) The histograph representing the number of SPAG9 expressing cells and PCNA expressing cells. The histograph distinctly revealed the significantly reduced number of SPAG9 and PCNA expressing cells in SPAG9 siRNA compared with control siRNA treated mice. Columns indicate mean; bars, standard error. * P < 0.0001, statistical significant. Original magnification, × 400; objective × 40.