Expression of gonadotropin and activin receptor messenger ribonucleic acidin human ovarian epithelial neoplasms

Activin receptors (ActRs) and gonadotropin receptor mRNA expression were in vestigated in 18 human ovarian epithelial neoplasms, Northern blot analysis showed the presence of 3,0-kb type Ia ActR, 6,0- and 3,0-kb type IIa ActR, and 5,0-kb type IIb ActR mRNA transcripts in total RNA prepared from the c ancer tissues, One carcinoma showed two major transcripts of a follicle-sti mulating hormone receptor (FSH-R) gene, 4.1 and 2.4 kb, whereas the other t wo carcinomas showed two major transcripts of the luteinizing hormone/human chorionic gonadotropin receptor (LH-R) gene, 5.4 and 2.4 kb, These results were further analyzed by studying the corresponding PCR-amplified FSH and LH-R cDNA obtained by reverse transcription of total RNA. Expression of FSH -R mRNA was confirmed in about half of the cancer tissues. The size of the FSH-R reverse transcription-PCR product was the same as in normal ovarian f ollicles, Similarly, expression of LH-R mRNA was also detected in about hal f of the cancers. Normal ovaries and cancer tissues were homogenized, and a ctivin concentrations were measured in extracts. Activin levels in normal o varian tissue were around 0.59 +/- 0.01 ng/mg protein (mean +/- SE; n = 5), and activin production was detected in every cancer tissue, except one-ser ous adenocarcinoma, The findings in this study demonstrated that activin an d ActRs are present in and synthesized by human ovarian epithelial neoplasm s. Thus, activin seems to be available as an autocrine/paracrine factor in epithelial neoplasms and may contribute to the expression of FSH-R, althoug h the roles of activin and gonadotropin in tumorigenesis has yet to be defi ned.