[Oncofertility and breast cancer]

Over the past decades, progresses in oncology have improved the recovery rates after numerous malignant diseases, including breast cancer, that strike young adults in childbearing age. Quality of life of young cancer survivors has become a major issue. However, anticancer therapies can have a detrimental impact on fertility. It is now well-established that all patients should receive information about the fertility risks associated with their cancer treatment and the fertility preservation options available. These techniques aim to limit the negative impact of chemotherapy on the ovaries or to preserve gametes before treatment. Currently, oocyte or embryo freezing after controlled ovarian hyperstimulation represents the most effective method for preserving female fertility. Over the past years innovative protocols of ovarian stimulation have been developed to enable breast cancer patients to undergo oocyte or embryo cryopreservation irrespective of the phase of the cycle or without exogenous follicle-stimulating hormone related increase in serum estradiol levels. When controlled ovarian hyperstimualtion cannot be implemented, other techniques such as cryopreservation of ovarian cortex, in vitro maturation or the use of GnRH agonists may be proposed. However, it is important to inform patients that all these fertility preservation techniques do not represent a guarantee of pregnancy.

[Fertility preservation in women of the childbearing age: Indications and strategies]

Advances on cryopreservation techniques now allow considering oocyte, embryo or ovarian tissue freezing for female fertility preservation. Originally developed for patients suffering from cancer, fertility preservation has rapidly invaded others medical fields, and represents now the standard of care for all young patient diagnosed with a disease that could impair fertility or having to receive possibly gonadotoxic treatment. As a result, autoimmune diseases, some genetic pathologies or iterative pelvic surgeries, at risk of premature ovarian failure, have become common indications of fertility preservation. In addition, the social egg freezing aiming at preventing the age-related fertility decline is still debated in France, although authorized in numerous countries. This review will discuss the different strategies of fertility preservation in young girls and women of reproductive age, regarding different medical or non-medical indications.

The influence of N-acetyl-l-cysteine on damage of porcine oocyte exposed to zearalenone in vitro

Zearalenone (ZEA), one of the mycotoxins produced by Fusarium fungi, impacts porcine reproduction by interfering with the estrogen signaling pathway. Previous studies have shown that ZEA inhibits porcine oocyte maturation through the formation of aberrant spindle. To explore the effect of ZEA on porcine oocyte meiotic maturation, the extent of both nuclear and cytoplasmic maturation was examined in this study. Compared with control group, presence of ZEA (3 μM) during oocyte maturation, significantly inhibited the polar body extrusions from 71% to 51%, and significantly increased intracellular reactive oxygen species (ROS) level (12.01 vs. 5.89). Intracellular glutathione (GSH) content in ZEA treatment group was lower than in the control group (1.08 pmol/oocyte vs. 0.18 pmol/oocyte), and cortical granules of cortical area distributed oocytes were reduced (88% vs. 62%). ZEA decreases cumulus expansion in both morphology and mRNA level (HAS2, PTX3, TNFAIP6 and CX43). Addition of N-acetyl-l-cysteine (NAC) to the oocyte maturation media reversed the ZEA-induced inhibition of polar body extrusion (from 69% to 81%), up-regulated ROS (from 7.9 to 6.5), down-regulated GSH content (from 0.16 to 0.82 pmol/oocyte) and recovered cumulus cells expansion in morphology and mRNA level. It is concluded that ZEA affects both oocyte nucleus and cytoplasmic maturation during in vitro maturation, and NAC can reverse these damages to some extent.