Etoposide damages female germ cells in the developing ovary

Abstract

BackgroundAs with many anti-cancer drugs, the topoisomerase II inhibitor etoposide is considered safe for administration to women in the second and third trimesters of pregnancy, but assessment of effects on the developing fetus have been limited. The purpose of this research was to examine the effect of etoposide on germ cells in the developing ovary. Mouse ovary tissue culture was used as the experimental model, thus allowing us to examine effects of etoposide on all stages of germ cell development in the same way, in vitro.ResultsFetal ovaries from embryonic day 13.5 CD1 mice or neonatal ovaries from postnatal day 0 CD1 mice were cultured with 50–150 ng ml−1 or 50–200 ng ml−1 etoposide respectively, concentrations that are low relative to that in patient serum. When fetal ovaries were treated prior to follicle formation, etoposide resulted in dose-dependent damage, with 150 ng ml−1 inducing a near-complete absence of healthy follicles. In contrast, treatment of neonatal ovaries, after follicle formation, had no effect on follicle numbers and only a minor effect on follicle health, even at 200 ng ml−1. The sensitivity of female germ cells to etoposide coincided with topoisomerase IIα expression: in the developing ovary of both mouse and human, topoisomerase IIα was expressed in germ cells only prior to follicle formation.ConclusionsExposure of pre-follicular ovaries, in which topoisomerase IIα expression was germ cell-specific, resulted in a near-complete elimination of germ cells prior to follicle formation, with the remaining germ cells going on to form unhealthy follicles by the end of culture. In contrast, exposure to follicle-enclosed oocytes, which no longer expressed topoisomerase IIα in the germ cells, had no effect on total follicle numbers or health, the only effect seen specific to transitional follicles. Results indicate the potential for adverse effects on fetal ovarian development if etoposide is administered to pregnant women when germ cells are not yet enclosed within ovarian follicles, a process that starts at approximately 17 weeks gestation and is only complete towards the end of pregnancy.Electronic supplementary materialThe online version of this article (doi:10.1186/s12885-016-2505-9) contains supplementary material, which is available to authorized users.

Comprehensive histochemical profiles of histone modification in male germline cells during meiosis and spermiogenesis: Comparison of young and aged testes in mice

“…anti-H3K4me2 rabbit polyclonal 1/500 Millipore (07-030) [13][14][15] anti-H3K4me3 rabbit polyclonal 1/500 Abcam (ab8580) [16][17][18] anti-H3K9me3 rabbit polyclonal 1/500 Abcam (ab8898) [19][20][21] anti-H3K27ac rabbit polyclonal 1/500 Abcam (ab4729) [22][23][24] anti-H3K27me2 rabbit polyclonal 1/500 Abcam (ab24684) [25,26] anti-H3K27me3 rabbit polyclonal 1/500 Millipore (07-449) [24,[27][28][29] anti-H3K79me2 rabbit polyclonal 1/500 Abcam (ab3594) [30][31][32] anti-H3K79me3 rabbit polyclonal 1/500 Abcam (ab2621) [33][34][35] anti-SCP3 mouse monoclonal 1/500 Abcam (ab97672) [36][37][38] anti-α-Tubulin (S2 Fig) mouse monoclonal 1/500 Sigma-Aldrich (T6199) [39,40] All antibodies are commercially available, and their specificity has been reported in previous studies.…”

Reduced retinoic acid synthesis accelerates prophase I and follicle activation

“…This present study, to our knowledge, is the first in-depth investigation into the impact of inhibition of retinoic acid synthesis on meiotic progression in the fetal ovary and its relationship with subsequent follicle formation and growth initiation. We have used the compound WIN 18,446 to inhibit retinoic acid synthesis in a fetal mouse ovary culture system that supports germ cell survival and progression through prophase I of meiosis up to diplotene arrest, followed by primordial follicle formation and subsequent growth initiation ( Stefansdottir et al . 2016 , Rosario et al 2019 ).…”

“…Primordial follicles (PMF) were defined as having only squamous pre-granulosa cells, transitionary follicles (TRNS) had both squamous and cuboidal granulosa cells, and primary follicles (PRIM) had a complete layer of cuboidal granulosa cells. Follicle health was assessed as described previously ( Stefansdottir et al . 2016 ).…”

Requirement for etoposide in the treatment of pregnancy related hemophagocytic lymphohistiocytosis: a multicenter retrospective study

“…In this study, for the one patient who used etoposide during her pregnancy, no congenital malformations could be found in the fetus. However, in a recent study in mice, the results indicate the potential for adverse effects on fetal ovarian development [26].…”