COMPARISON OF TELOMERASE ACTIVITY IN NORMAL CHORIONIC VILLI TO TROPHOBLASTIC DISEASES

Trophoblasts are derived from the normal placenta, and they infiltrate into the endometrium and the maternal blood vessels under strict cont rol but, unlike malignant cells, never metastasize. To understand the proliferative characteristics of trophoblasts and its related disorder s, we assessed telomerase activity in chorionic villi obtained from 27 normal individuals, 9 hydatidiform moles, and 2 choriocarcinomas. Tel omerase activity was detected in 13/27 (48%) normal chorionic villi sa mples. The detectability and the level of telomerase activity depended on gestational age; 8/10 (80%) villi samples in the first trimester ( relative telomerase activity; 1.77+/-1.37), whereas 2/8 (25%) villi sa mples in the second trimester (0.28+/-1.52) and 3/9 (33%) in the third trimester (0.28+/-0.43) had telomerase activity. Telomerase activity of normal chorionic villi in the first trimester was higher than that of the third trimester (P=0.0251). In contrast, all mole samples had i ncreased telomerase activity compared to normal villi (3.17+/-2.81, P= 0.0152). Thus, a relationship may exist among cell proliferation, telo merase activity, and progression to trophoblastic disease.