The isolation and long-term culture of normal human endometrial epithelium and stroma. Expression of mRNAs for angiogenic polypeptides basally and on oestrogen and progesterone challenges.

A highly reproducible and technically straightforward technique for the isolation and long-term culture of normal human endometrial epithelial cells is described. The essential conditions for long-term culture are that the cells be seeded onto a gelatin matrix and that 'endothelial cell growth supplement' be present in the culture medium. Normal endometrial epithelial cells express cytokeratins and oestrogen receptors. They may be passaged five to six times without change in properties. Growth of normal endometrial epithelial cells was stimulated by 17-beta-oestradiol and epidermal growth factor. Expression of the mRNA coding for seven polypeptide angiogenic factors, by normal endometrial epithelial, stromal and three endometrial carcinoma lines, was examined. The endometrial epithelial and stromal cells express mRNA for the polypeptide angiogenic factors, basic fibroblast growth factor, vascular endothelial cell growth factor, transforming growth factor-beta 1 and pleiotrophin, as well as the cytokine midkine. Expression of the mRNA for both vascular endothelial growth factor and midkine by normal endometrial epithelial cells showed a 2-fold increase on treatment with a physiological dose of 17-beta-oestradiol (10(-10) M) while, in contrast, the mRNA of transforming growth factor-beta 1 decreased 4-fold on treatment with 17-beta-oestradiol (10(-10) M) and was abolished by exposure to progesterone (5 x 10(-9) M). Expression of the mRNAs for angiogenic polypeptides by the endometrial carcinoma lines was more restricted.