Figure 6.

The therapeutic evaluation of cyc-LHSPW in vivo and in vitro. (A) The effect of the three peptides cyc-LHSPW, LHSPW and cyc-nHSPW on the clonogenic survival of APN-expressing PC3 cells and APN-null DU145 cells. (B) Tumor growth of PC3 and DU145 xenograft mice treated with 40 mg/kg of cyc-LHSPW, cyc-NGR or saline control three times a week for four weeks. Mice were first injected with drug via tail vein starting at day 0 of the study and continued until tumor volumes >1000 mm³ were observed as dictated by our animal protocol. Each treatment group consisted of n = 9 mice/xenograft. Statistical significance of cyc-LHSPW compared with control is denoted by: *P < 0.05; and **P < 0.01, as determined by the Student t test. (C) At the end of the study, PC3 tumors were removed from the treated arms and stained for the proliferation maker Ki67. Decreased Ki67 staining is evident in the cyc-LHSPW treated arm.