Figure 6
Knockdown of PTOV1 in prostate cancer cells inhibits tumor growth and metastasis of PC-3 cells in immunodeficient mice. (A) PTOV1 is required for optimal tumor formation of PC-3 cells in vivo. PC-3 cells with integrated luciferase gene (3 x106), knocked down for PTOV1 (n = 5) by sh1397 or control lentivirus (n = 5), were implanted subcutaneously into the right flank of SCID-beige male mice and monitored by in vivo bio-luminescent imaging. Mean values + SEM are displayed. Statistically significant differences in the growth of knockdown vs. control cells were observed. ** p = 0.001. (B) Immunohistochemistry of explanted tumors. A strongly decreased expression of PTOV1 is detected in tumors formed by shPTOV1 cells vs shControl derived tumors. In contrast, tumors derived from shPTOV1 cells express high levels of HES1 and HEY1 proteins compared to shControl and grew metasases at significantly later times (p = 0.001) as compared to control cells.