Blood vessel morphology in brain tumors.

<p>A: PDGF-C expression causes a decrease in vessel diameter over 15 days of growth. B: At day 15 after implantation, the vessel size distribution in the PDGF-C over-expressing tumors resembles that of normal brain, while the siRNA and parental tumors have distributions shifted to higher diameters, with significant numbers of large-diameter (>25 µm) vessels. C: representative 2-photon images of the vessel networks.