Figure 3.
Tumor growth inhibition mediated by mAb 38C2 in the presence of SCS-873. Tumor growth inhibition studies were based on mouse models of human KS (A) and human colon cancer (B). Tumor induction was performed by s.c. injection of 5 × 106 SLK cells or 2 × 106 SW1222 cells in the right flank of nude mice. Four different groups of five animals were treated between days 1 and 20 after tumor induction. Treatment involved 200-μl i.v. injections of either PBS alone (groups 1 and 2) or 2.5 mg/ml mAb 38C2 in PBS (groups 3 and 4) once a week on days 1, 8, and 15. In addition, 50-μl i.p. injections of 10 mg/ml SCS-873 in 50% PBS, 25% DMSO, and 25% ethanol (groups 2 and 4) or solvent alone (groups 1 and 3) were given on days 2, 5, 8, 11, 14, 17, and 20. Tumor volumes of treated animals were measured every third day starting on day 9. Shown are average tumor volumes ± SD. Statistical significant differences in tumor volume between group 4 (38C2/SCS-873) and group 2 (SCS-873 alone) were observed from day 15 (A) or day 12 (B) until the end of the experiment (P < 0.05 based on two-tailed Student's t tests).