| First Author | Laws MJ | Year | 2014 |
| Journal | PLoS Genet | Volume | 10 |
| Issue | 3 | Pages | e1004230 |
| PubMed ID | 24603706 | Mgi Jnum | J:210994 |
| Mgi Id | MGI:5573006 | Doi | 10.1371/journal.pgen.1004230 |
| Citation | Laws MJ, et al. (2014) Dysregulated estrogen receptor signaling in the hypothalamic-pituitary-ovarian axis leads to ovarian epithelial tumorigenesis in mice. PLoS Genet 10(3):e1004230 |
| abstractText | The etiology of ovarian epithelial cancer is poorly understood, mainly due to the lack of an appropriate experimental model for studying the onset and progression of this disease. We have created a mutant mouse model in which aberrant estrogen receptor alpha (ERalpha) signaling in the hypothalamic-pituitary-ovarian axis leads to ovarian epithelial tumorigenesis. In these mice, termed ERalphad/d, the ERalpha gene was conditionally deleted in the anterior pituitary, but remained intact in the hypothalamus and the ovary. The loss of negative-feedback regulation by estrogen (E) at the level of the pituitary led to increased production of luteinizing hormone (LH) by this tissue. Hyperstimulation of the ovarian cells by LH resulted in elevated steroidogenesis, producing high circulating levels of steroid hormones, including E. The ERalphad/d mice exhibited formation of palpable ovarian epithelial tumors starting at 5 months of age with 100% penetrance. By 15 months of age, 80% of ERalphad/d mice die. Besides proliferating epithelial cells, these tumors also contained an expanded population of luteinized stromal cells, which acquire the ability to express P450 aromatase and synthesize E locally. In response to the elevated levels of E, the ERalpha signaling was accentuated in the ovarian epithelial cells of ERalphad/d mice, triggering increased ERalpha-dependent gene expression, abnormal cell proliferation, and tumorigenesis. Consistent with these findings, treatment of ERalphad/d mice with letrozole, an aromatase inhibitor, markedly reduced circulating E and ovarian tumor volume. We have, therefore, developed a unique animal model, which serves as a useful tool for exploring the involvement of E-dependent signaling pathways in ovarian epithelial tumorigenesis. |
