TELOMERE SHORTENING IN UTERINE LEIOMYOMAS

OBJECTIVE: To gain a better understanding of proliferation control mec hanisms in a common benign tumor, we investigated the mean telomere le ngth and the clonality of uterine leiomyomas. STUDY DESIGN: Deoxyribon ucleic acid from uterine leiomyomas and from the adjacent normal myome trium of 51 patients (total number of uterine leiomyomas 107, 28 patie nts with single leiomyoma, 23 patients with multiple leiomyomas rangin g from 2 to 8 myoma nodules per case) was hybridized to a telomeric ol igonucleotide probe by Southern blot and chemiluminescent detection. T he mean telomere length was evaluated by densitometry. Clonality was a ssessed with use of the phosphoglycerokinase gene polymorphism. RESULT S: The mean telomere length was significantly shorter in uterine leiom yomas (median 7950 bp, interquartile range 7261 to 8372 bp) than in no rmal myometrium (median 9688 bp, interquartile range 8528 to 10535 bp) (P <.001). There was no correlation between tumor size and telomere a ttrition. Multiple uterine leiomyomas were found to have an independen t clonal origin. CONCLUSIONS: Telomere attrition in uterine leiomyomas reflects enhanced proliferation activity in the course of tumor evolu tion. The basic telomere lengths differ in the myocytes from which the uterine leiomyomas originate, probably explaining the lack of correla tion between telomere attrition and tumor size.