Figure 3.

Vascular collapse in response to VEGF withdrawal. Signal enhancement in response to hyperoxia was monitored in C6-pTET-VEGF tumors in nude mice, by switching the mice from inhalation of 95% air/5% CO₂ tp 95% O₂/5% CO₂ (carbogen). (A) In the absence of tetracycline, the tumors were hypervascular in accord with over-expression of VEGF. (B) Forty-eight hours after administration of tetracycline, suppressing VEGF over-expression, a significant drop in vascular function was observed (see also Refs. [20,21]). These data are from work performed by R. Abramovitch, H. Dafni, E. Smouha, L. Benjamin and M. Neeman.