Differential expression of genes coding for EGF-like factors and ADAMTS1 following gonadotropin stimulation in normal and transformed human granulosa cells.
We have demonstrated previously that the synthesis of epiregulin and amphiregulin, of the EGF-like growth factor family, is stimulated by luteinizing hormone in human follicular (granulosa) cells obtained from in vitro fertilization program. In the present work, we demonstrate that H89, a PKA inhibitor, attenuated the expression of these growth factors both in the mRNA and the protein levels, suggesting PKA involvement in this signaling pathway. SV40-transformed human granulosa cells showed higher basal levels of epiregulin and amphiregulin than normal cells, which were still elevated following cAMP stimulation by Forskolin. Cleavage by a disintegrin and metalloproteinases (ADAMs) is essential for activation of these growth factors, allowing their interaction with EGF receptor. Expression of ADAMTS1 and ADAM12 was downregulated by cAMP in normal, but not in SV40-transformed cells, suggesting that in normal cells epiregulin and amphiregulin activity is downregulated by a feedback mechanism that may be lost in SV40-transformed cells and their loss of downregulation may be involved in the development of ovarian tumors.
Freimann
Sarit
S
Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot 76100, Israel.
Ben-Ami
Ido
I
Dantes
Ada
A
Armon
Leah
L
Ben Ya'cov-Klein
Avital
A
Ron-El
Raphael
R
Amsterdam
Abraham
A
D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; D001483:Base Sequence; D002461:Cell Line, Transformed; D005576:Colforsin / Q000494:pharmacology; D017931:DNA Primers; D019483:Disintegrins / Q000235:genetics*; D004815:Epidermal Growth Factor / Q000235:genetics*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000494:pharmacology*; D005786:Gene Expression Regulation / Q000187:drug effects*; D006107:Granulosa Cells / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007986:Luteinizing Hormone / Q000494:pharmacology*; D008666:Metalloendopeptidases / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction
D017931:DNA Primers; D019483:Disintegrins; D005576:Colforsin; D004815:Epidermal Growth Factor; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; C103859:ADAMTS1 protein, human; D008666:Metalloendopeptidases