QUANTIFICATION OF TUMOR-INDUCED ANGIOGENESIS BY IMAGE-ANALYSIS

Quantitative techniques for in vivo and in vitro angiogenesis were dev eloped using an image analyser. In the in vivo study, a Millipore cham ber filled with mouse sarcoma 180 (S180) cells was transplanted subcut aneously to the dorsal side of a mouse, and the area of neovasculariza tion induced by the tumour cells was quantified by image analysis. Ima ges of vascular networks with poor contrast had their contrast improve d by Laplacean transformation. The area of vascular network was 16.9 m m(2) in the control group without tumour cells and 44.2 mm(2) in the g roup with tumour cells, demonstrating a significant increase in neovas cularized area by tumour cells. In the in vitro study, migration of va scular endothelial cells was induced with conditioned media of S180 ce lls. Image analysis was used to count automatically the nuclei of migr ated endothelial cells, which were stained violet with Giemsa's soluti on, This automated measurement by image analyser is expected to save l abour and time. Checkerboard analysis revealed that the endothelial ce ll migration induced by S180-conditioned medium was due to chemotaxis. The quantitation method using an automated image analyser is valuable in evaluating the induction of neovascularization by tumours and the effect of pharmacological agents on tumour angiogenesis in vivo and in vitro.