Fig. 6.

Effects of DB16 and DB21 in the B16F10 melanoma mouse model are shown. Tumors were allowed to grow to approximately 50 mm³, and treatment with DB16 and DB21, as well as with parent 6DBF7 and anginex as controls, was initiated on day 7 by i.p. injection twice daily for a total dose of 10 mg/kg/day for 5 days (A). General control groups of animals were treated with PBS alone. Tumor volumes (for all groups n = 10, ±S.E.M.) are plotted as mm³ versus days postinoculation. Tumor volumes were determined by measuring diameters of tumors using calipers, and using the equation for the volume of a spheroid, (a² × b × Π) / 6, where “a” is the width and “b” the length of the tumor. Tumor weights correlated well with tumor volumes calculated in this way. For DB21-, 6DBF7-, and anginex-treated mice, (B) shows immunohistochemistry on tumor tissue sections stained for CD31 (endothelial cell marker) and DAPI (cell nuclei marker). Compared with control tissue, DB21 had the greatest effect on reducing vessel density in tumors, as quantified in (C) by pixilation and averaging of 20 images for each treatment regimen. Weight gain and hematocrit levels from treatment with DB21 are shown in panels (D) and (E), respectively.