Expression of insulin-like growth factor [IGF] -Ia , IGF-Ib , and IGF-II messenger ribonucleic acid in uterine leiomyoma

Kim, J K; Suh, C S; Kim, S H; Choi, Y M; Moon, S Y; Kang, S B; Lee, J Y

Abstract

OBJECTIVES
To evaluate the insulin-like growth factor[IGF]s gene expression in tissues from uterine leiomyoma and adjacent normal myometrium and to investigate the in vivo effects of gonadotropin releasing hormone agonist[GnRHa] on these expression.
METHODS
IGF-Ia, IGF-Ib, and IGF-II messenger ribonucleic acid[mRNA] transcripts were measured in total RNA extracted from paired specimens of leiomyoma and adjacent myometrium from untreated patients[n=20] during late proliferative phase of menstrual cycle and from leiomyoma from GnRHa - pretreated patients by Northen blot using specific human compementary deoxyribonucleic acid[cDNA] probes. All statistics were performed by paired t -test and student`s t-test.
RESULTS
Four IGF-Ia transcripts representing 1.2, 1,7, 5.0, 7.5 kilobase[kb], and IGF-Ib transcript of 1,2kb were detected in leiomyoma and adjacent myometrium. Also, in these tissues, the 2.2, 3.2, and 4.9 kb IGF-II mRNA were detected and the 6.0kb IGF-II mRNA only in a few leiomyoma. The relative abundance of 5.0 kb IGF-Ia mRNA, 3.2 and 4.9 kb IGF-II mRNA in leiomyoma were siginficantly higer than those in adjacent myometrium but no significant difference in the relative abundance of any other IGF mRNA was not found between leiomyoma and adjacent myometrium. The relative abundance of IGF-Ia, IGF-Ib and IGF-II mRNA in GnRHa- preexposed leiomyoma.was not different from that in GnRHa- unexposed tissue respectively.
CONCLUSIONS
IGF-I and IGF-II may be involved in leiomyoma growth at the molecular level but GnRHa does not affect the IGFs gene expression in leiomyoma.