Angiogenesis-inducing ability of human bladder epithelium cell lines and "spontaneously" transformed murine...

Ten human bladder epithelium cell lines were tested for their ability to induce blood vessel formation after intradermal injection into irradiated ST/a mice. Cell lines that were shown to be tumorigenic in nude mice, were able to evoke angiogenesis of a higher intensity than nontumorigenic cell lines. No difference was observed between the angiogeneic ability of tumorigenic cells originating from tumors and from in vitro transformed urothelium of nontumor origin. Similarly the origin of nontumorigenic urothelial cell lines did not show any influence on their angiogeneic abilities, but nontumorigenic cell lines which had undergone "infinite growth transformation" exhibited a higher angiogeneic activity than nontumorigenic cell lines with a finite life. The angiogeneic reaction evoked by human bladder epithelium cell lines showed cell dose- and time-dependence; but it was unrelated to the growth potential of the cultured cells. Two "spontaneously" altered sarcoma-producing murine cell lines showed a higher angiogeneic activity than tumorigenic human bladder epithelial cells. The angiogeneic response to these two murine cell lines was unrelated to morphological signs of transformation and to differences in growth rate, serum requirement, saturation density, anchorage dependence, and isoimmunizing properties.