Fig. 3. Human skin grafts on SCID mice promote the growth of tumors induced by KS SLK cells, and anti-VEGF antisera blocks tumor development. Two million KS SLK cells were inoculated under a human (neonatal) foreskin graft, a human adult skin graft, or nongrafted skin of SCID mice and observed for tumor growth. After 3 weeks, the sites were examined macroscopically for lesions; tumor volume was measured, and lesions were resected. The mean tumor volumes present under both the human neonatal and adult skin grafts (180 ± 120/mm3 and 170 ± 121/mm3, respectively) were significantly larger (P < 0.0005 and P < 0.0005) than the volume of tumors under the endogenous mouse skin (15 ± 1/mm3). In another set of experiments, 2 million KS SLK cells were combined with 50 µg of control antiserum or anti-VEGF antisera, and the combination was inoculated under human skin grafts. After 3 weeks, the sites were examined macroscopically for lesions; tumor volume was measured, and lesions were resected. The mean tumor volume of sites inoculated with control antisera (170 ± 58 mm3) was significantly larger (P < 0.0005) than the volume of tumors from sites inoculated with anti-VEGF antisera (10 ± 1/mm3). Neonatal skin was derived from resected foreskin; adult skin was from mastectomy resection. Each column represents the volume of one tumor lesion from one mouse. Inoculation sites under murine skin were made under skin contralateral to skin grafts.