Publications / Awards 2

Articles dans des revues avec comité de lecture

2025

Hormonal factors predictive of fertility in patients with breast cancer interrupting adjuvant endocrine therapy to attempt pregnancy in POSITIVE trial.

The POSITIVE trial showed that premenopausal women with breast cancer (BC) can safely pause adjuvant endocrine treatment (ET) to attempt conception. 74 % of patients conceived spontaneously or through assisted reproductive technology (ART); Investigating hormonal factors that predict fertility was a key secondary endpoint.

Corrigendum to "Hormonal factors predictive of fertility in patients with breast cancer interrupting adjuvant endocrine therapy to attempt pregnancy in POSITIVE trial" [The Breast 83 (2025) 104547].

Carboplatin and paclitaxel induced-gonadotoxicity on the ovarian reserve of young breast cancer patients with BRCA1 mutation.

Are ovarian tissue fragments from patients with BReast CAncer gene 1 (BRCA1)-mutated breast cancer (BC) more sensitive to carboplatin and/or paclitaxel exposure compared to those from non-mutated patients with BC?

Breastfeeding after breast cancer in young BRCA carriers.

We investigated safety of breastfeeding after breast cancer in patients carrying germline BRCA pathogenic or likely pathogenic variants.

Assisted reproductive technology in young BRCA carriers with a pregnancy after breast cancer: An international cohort study

Introduction: Very limited data exist on assisted reproductive technology (ART) use in BRCA1/2 carriers conceiving after breast cancer. This study aimed to investigate the safety of ART to achieve a pregnancy after breast cancer in BRCA1/2 carriers. Methods: This is an international, hospital-based, retrospective cohort study including BRCA1/2 carriers with a pregnancy after prior breast cancer diagnosis at ≤ 40 years of age between 2000 and 2020. Outcomes were compared between young BRCA1/2 carriers who conceived using ART and those who conceived spontaneously. Results: Among 543 BRCA1/2 carriers with a pregnancy after breast cancer, 436 conceived spontaneously and 107 using ART. Of 107 pregnancies achieved with ART, 45 (42.1 %) were obtained using oocytes/embryo cryopreserved at diagnosis, 33 (30.8 %) after controlled ovarian stimulation for in-vitro-fertilization/intracytoplasmic sperm injection or ovulation induction for intrauterine insemination or planned intercourse after anticancer treatments, 21 (19.6 %) after oocyte donation, while for 8 (7.5 %) patients type of ART was missing. Compared to patients in the no-ART group, those in the ART group were older at the time of conception, had more frequently hormone receptor-positive breast cancer and a longer median time from cancer diagnosis to conception. At a median follow-up of 5.2 years after conception, no apparent detrimental effect of ART on disease-free survival was observed (adjusted HR=0.72, 95 % CI 0.39-1.34). Conclusion: In young BRCA1/2 carriers with a pregnancy after breast cancer, ART use did not appear to be associated with increased risk of DFS events.

Novel insights into human CRISP2: localization in reproductive tissues and sperm, and molecular characterization†.

CRISP2 is enriched in the male reproductive system of mammals and plays roles in spermatogenesis, sperm motility, and fertilization. Although extensively investigated in rodents and boars, human CRISP2 (hCRISP2) remains poorly studied, particularly concerning its localization in testicular and epididymal tissues and its molecular features. In this study, we used immunofluorescence to determine the localization of hCRISP2 in testis, epididymis, and ejaculated sperm. While no expression was observed in the epididymal epithelium, hCRISP2 was detected at different stages during spermatogenesis. Specifically, hCRISP2 was found in the nucleus of primary spermatocytes and of both round and early elongated spermatids. In elongated spermatids, it was additionally observed in the cytoplasm, the flagellum, and the equatorial segment of the acrosome (EqS). The presence of aggregated material with hCRISP2 immunoreactivity in the apical pole of Sertoli cells suggests that most of the hCRISP2 involved in spermatogenesis is phagocytized by these cells during spermiation. In ejaculated sperm, hCRISP2 was found in the cytoplasmic droplet, flagellum, and EqS, consistent with its described roles in sperm motility and gamete fusion. Native and denaturing electrophoresis combined with western blot analyses depicted the ability of hCRISP2 to form stable high molecular weight complexes, and mass spectrometry revealed that these complexes likely consist exclusively of hCRISP2. Furthermore, we showed that hCRISP2 undergoes only limited post-translational modifications. These findings shed light into the dynamic localization of hCRISP2 throughout spermatogenesis and in ejaculated sperm, as well as its molecular features, enhancing our understanding of its functional roles and relevance for male fertility.

Effect of Surface Modification of Gold Nanoparticles Loaded with Small Nucleic Acid Sequences on Cytotoxicity and Uptake: A Comparative Study In Vitro

Nanoparticle technology, particularly gold nanoparticles (AuNPs), is being developed for a wide range of applications, including as a delivery system of peptides or nucleic acids (NA). Their use in precision medicine requires detailed engineering of NP functionalization to optimize their function and minimize off-target toxicity. Two main routes can be found in the literature for the attachment of NA strands to AuNPs: covalent binding via a thiol group or passive adsorption onto a specially adapted coating previously applied to the metallic core. In this latter case, the coating is often a positively charged polymer, as polyethylenimine, which due to its high positive charge can induce cytotoxicity. Here, we investigated an innovative strategy based on the initial coating of the particles using calix[4]arene macrocycles bearing polyethylene glycol chains as an interesting alternative to polyethylenimine for NA adsorption. Because any molecular modification of AuNPs may affect the cytotoxicity and cellular uptake, we compared the behavior of these AuNPs to that of particles obtained via a classical thiol covalent attachment in MCF-7 and GC-1 spg cell lines. We showed a high biocompatibility of both AuNPs-NA internalized in vitro. The difference in subcellular localization of both AuNPs-NA in MCF-7 cells compared to GC-1 spg cells suggests that their subcellular target is cell- and coating-dependent. This finding provides valuable insights for developing alternative NA delivery systems with a high degree of tunability.

The Effects of Endometriosis on Oocyte and Embryo Quality.

Endometriosis is a complex and multifaceted gynecological disorder characterized by the abnormal growth and presence of endometrial-like tissue outside the confines of the uterine cavity. It can lead to a wide range of distressing symptoms, including chronic pelvic pain, heavy and/or irregular menstrual bleeding, and significant challenges with fertility. While the association between endometriosis and infertility is well recognized, the precise mechanisms through which the disease affects oocyte and embryo quality remain controversial. Studies that utilized transcriptomic, metabolomic, and ultrastructural analyses indicated dysregulated energy metabolism, oxidative stress, mitochondrial dysfunction, and inflammatory alterations in the ovarian microenvironment. The impact of endometriosis on fertilization, embryo development, and implantation remains debated, with conflicting findings across different study designs. Some investigations reported impaired oocyte morphology, reduced fertilization rates, and poorer embryo quality, while others suggested that endometriosis does not significantly affect ART outcomes when confounding factors are controlled. Recent studies highlight the importance of distinguishing the disease severity, lesion location, and prior surgical interventions when assessing reproductive outcomes. The need for standardized methodologies in evaluating oocyte and embryo quality, alongside personalized treatment approaches, is emphasized. Further research is warranted to elucidate the precise molecular mechanisms underlying these effects and to develop targeted therapeutic strategies aimed at improving ART success in women with endometriosis. This narrative review provides a thorough examination of the previous research on the impact of endometriosis on oocyte and embryo quality, highlighting both the known mechanisms and the areas that require further investigation. This will help to guide future research and clinical management strategies to improve reproductive outcomes for women with endometriosis.

Can we really protect the ovary from chemotherapy damage?

Future alternatives to current fertility preservation methods such as pharmacological strategies to prevent chemotherapy-induced ovarian damage in female cancer patients are of growing interest. Chemotherapeutic agents, especially alkylating agents, cause DNA damage and apoptosis in ovarian follicles, significantly reducing ovarian reserve. To mitigate this gonadotoxicity, various emerging strategies are being explored, including kinase inhibitors, PI3K/Akt/mTOR pathway inhibitors, antioxidants, miRNAs and GnRH agonists. These treatments work by preventing follicular apoptosis or excessive activation of primordial follicles. Although promising results have been observed in vitro and in vivo in rodent models, further investigations to bypass their limitations are needed to confirm their efficacy and safety. These challenges include the non-interference with anti-tumoral effect of chemotherapy and the specificity of fertoprotective agents to ovaries.

2024

Policy brief of the Belgian Europe's Beating Cancer Plan mirror group: children, adolescents and young adults with cancer

Abstract Children and Adolescents and Young Adults with cancer represent a young population with specific needs, which need to be addressed in a patient- and cancer-driven way. There is an urgent need to support and extend the ongoing initiatives in Belgium. First, multidisciplinary care programmes dedicated to children need to be reviewed, and those for Adolescents and Young Adults need to be developed with close collaboration between paediatric and adult oncology and haematology teams. This needs to be done considering the entire patient journey; from cancer prevention, diagnosis, treatment, rehabilitation, follow-up of late effects, transition pathways between paediatric and adult wards, and palliative care. Second, national haemato/oncology precision programmes adapted to this young population with rare cancers, including infrastructure to manage cancer gene predisposition in CAYAs with cancers and their relatives, needs to be developed. This multi-level plan aims to ensure improved outcome with high quality of care for the young population with cancer in Belgium in line with Europe's Beating Cancer Plan initiatives.

Perinatal outcomes of pregnancies following autologous cryopreserved ovarian tissue transplantation: a systematic review with pooled analysis

Objective: This study aimed to synthesize the existing evidence on perinatal outcomes after autologous cryopreserved ovarian tissue transplantation, concurrently identifying key factors influencing these outcomes. Data Sources: A comprehensive search was performed on MEDLINE, Embase, and Cochrane Library databases to identify relevant studies on the effect of autologous cryopreserved ovarian tissue transplantation on perinatal outcomes from inception to October 22, 2023. Where there was missing information, the authors were contacted for updated data. Study Eligibility Criteria: Observational studies, such as cohort studies, case series, and case reports that reported a live birth after autologous cryopreserved ovarian tissue transplantation, were considered eligible. Studies lacking data on women's demographic characteristics, autologous cryopreserved ovarian tissue transplantation procedure details, or perinatal outcomes were excluded. In addition, cases involving fresh or nonautologous transplantations and those addressing primary ovarian insufficiency were excluded. Methods: Two reviewers (M.E. and E.U.) independently performed the study selection, data extraction, and risk of bias assessment, and the results were then reviewed together. The PRISMA guidelines were followed, and the protocol was registered on PROSPERO (CRD42023469296). Results: This review included 58 studies composed of 122 women with 162 deliveries (154 singletons and 8 twins) after autologous cryopreserved ovarian tissue transplantation, resulting in 170 newborns. Of note, 83.6% of the women had a malignant disease. Moreover, most of these women (51.0%) were exposed to some form of chemotherapy before ovarian tissue cryopreservation. Of the 162 childbirths, 108 (66.7%) were conceived naturally, and 54 (33.3%) were conceived through assisted reproductive techniques. The birthweight of 88.5% of newborns was appropriate for gestational age, whereas 8.3% and 3.1% were small for gestational age and large for gestational age, respectively. The preterm birth rate was 9.4%, with the remaining being term deliveries. Hypertensive disorders of pregnancy were noted in 18.9% of women, including pregnancy-induced hypertension in 7.6%, preeclampsia in 9.4%, and hemolysis, elevated liver enzymes, and low platelet count in 1.9%. The incidences of gestational diabetes mellitus and preterm premature rupture of membranes were 3.8% for each condition. Neonatal anomalies were reported in 3 transplant recipients with 4 newborns: arthrogryposis, congenital cataract, and diaphragmatic hernia in a twin. Finally, among the recipients' characteristics, not receiving chemotherapy before ovarian tissue cryopreservation (odds ratio, 0.23; 95% confidence interval, 0.07-0.72; P=.012) and natural conception (odds ratio, 0.29; 95% confidence interval, 0.09-0.92; P=.035) were associated with a lower perinatal complication rate. Conclusion: On the basis of low certainty evidence from observational studies, perinatal complication rates did not increase after autologous cryopreserved ovarian tissue transplantation compared with the general pregnant population, except for preeclampsia. This could be due to chemotherapy exposure, underlying medical conditions, and the common use of assisted reproductive techniques. Further larger studies are needed to explore the causes of increased preeclampsia incidence in autologous cryopreserved ovarian tissue transplantation pregnancies.

Fertility Preservation and Assisted Reproduction in Patients With Breast Cancer Interrupting Adjuvant Endocrine Therapy to Attempt Pregnancy.

We investigated time to pregnancy, efficacy and safety of fertility preservation, and assisted reproductive technologies (ARTs) in women with early hormone receptor-positive breast cancer (BC) desiring future pregnancy.

2023

BRCA Mutations and Fertility Preservation.

Hereditary cancers mostly affect the adolescent and young adult population (AYA) at reproductive age. Mutations in BReast CAncer (BRCA) genes are responsible for the majority of cases of hereditary breast and ovarian cancer. BRCA1 and BRCA2 act as tumor suppressor genes as they are key regulators of DNA repair through homologous recombination. Evidence of the accumulation of DNA double-strand break has been reported in aging oocytes, while BRCA expression decreases, leading to the hypothesis that BRCA mutation may impact fertility. Moreover, patients exposed to anticancer treatments are at higher risk of fertility-related issues, and BRCA mutations could exacerbate the treatment-induced depletion of the ovarian reserve. In this review, we summarized the functions of both genes and reported the current knowledge on the impact of BRCA mutations on ovarian ageing, premature ovarian insufficiency, female fertility preservation strategies and insights about male infertility. Altogether, this review provides relevant up-to-date information on the impact of BRCA1/2 mutations on fertility. Notably, BRCA-mutated patients should be adequately counselled for fertility preservation strategies, considering their higher sensitivity to chemotherapy gonadotoxic effects.

The Role of microRNA in Spermatogenesis: Is There a Place for Fertility Preservation Innovation?

Oncological treatments have dramatically improved over the last decade, and as a result, survival rates for cancer patients have also improved. Quality of life, including concerns about fertility, has become a major focus for both oncologists and patients. While oncologic treatments are often highly effective at suppressing neoplastic growth, they are frequently associated with severe gonadotoxicity, leading to infertility. For male patients, the therapeutic option to preserve fertility is semen cryopreservation. In prepubertal patients, immature testicular tissue can be sampled and stored to allow post-cure transplantation of the tissue, immature germ cells, or in vitro spermatogenesis. However, experimental techniques have not yet been proven effective for restoring sperm production for these patients. MicroRNAs (miRNAs) have emerged as promising molecular markers and therapeutic tools in various diseases. These small regulatory RNAs possess the unique characteristic of having multiple gene targets. MiRNA-based therapeutics can, therefore, be used to modulate the expression of different genes involved in signaling pathways dysregulated by changes in the physiological environment (disease, temperature, ex vivo culture, pharmacological agents). This review discusses the possible role of miRNA as an innovative treatment option in male fertility preservation-restoration strategies and describes the diverse applications where these new therapeutic tools could serve as fertility protection agents.

Safety of pregnancy after breast cancer in young women with hormone receptor-positive disease: a systematic review and meta-analysis.

Despite increasing evidence on the safety of pregnancy after anticancer treatments in breast cancer survivors, many physicians and patients remain concerned about a potential risk of pregnancy specifically in the case of hormone receptor-positive breast cancer.

A Journey to Reach the Ovary Using Next-Generation Technologies.

Although effective in terms of the chances of future live birth, the current methods for fertility preservation, such as oocyte, embryo, or ovarian tissue cryopreservation, cannot be offered to all cancer patients in all clinical contexts. Expanding options for fertility preservation is crucial to addressing the need to encompass all situations. One emerging strategy is pharmacoprotection, a non-invasive approach that has the potential to fill existing gaps in fertility preservation. In addition to the identification of the most effective therapeutic agents, the potential for off-target effects remains one of the main limitations of this strategy for clinical application, particularly when healthy ovarian tissue is targeted. This review focuses on the advances in pharmacoprotective approaches and the challenge of targeting the ovaries to deliver these agents. The unique properties of gold nanoparticles (AuNPs) make them an attractive candidate for this purpose. We discuss how AuNPs meet many of the requirements for an ideal drug delivery system, as well as the existing limitations that have hindered the progression of AuNP research into more clinical trials. Additionally, the review highlights microRNA (miRNA) therapy as a next-generation approach to address the issues of fertility preservation and discusses the obstacles that currently impede its clinical availability.

The Role of Cyclin-Dependent Kinases (CDK) 4/6 in the Ovarian Tissue and the Possible Effects of Their Exogenous Inhibition.

The combination of cyclin-dependent kinase (CDK) 4/6 inhibitors with endocrine therapy is the standard treatment for patients with HR+/HER2- advanced breast cancer. Recently, this combination has also entered the early setting as an adjuvant treatment in patients with HR+/HER2- disease at a high risk of disease recurrence following (neo)adjuvant chemotherapy. Despite their current use in clinical practice, limited data on the potential gonadotoxicity of CDK4/6 inhibitors are available. Hence, fully informed treatment decision making by premenopausal patients concerned about the potential development of premature ovarian insufficiency and infertility with the proposed therapy remains difficult. The cell cycle progression of granulosa and cumulus cells is a critical process for ovarian function, especially for ensuring proper follicular growth and acquiring competence. Due to the pharmacological properties of CDK4/6 inhibitors, there could be a potentially negative impact on ovarian function and fertility in women of reproductive age. This review aims to summarize the role of the cyclin D-CDK4 and CDK6 complexes in the ovary and the potential impact of CDK4/6 inhibition on its physiological processes.

Regulation of follicular activation signaling pathways by in vitro inhibition of YAP/TAZ activity in mouse ovaries.

The Hippo pathway plays a crucial role in the regulation of follicular activation, which constitutes the first step of the folliculogenesis process. Disruption of this pathway occurs in several non-physiological contexts, after fragmentation for ovarian tissue cryopreservation procedures or chemotherapy exposure, leading to massive follicular growth and depletion. This study aimed to investigate the effect of controlling the Hippo pathway using verteporfin (VERT) during in vitro ovarian culture and to evaluate its potential preventive effects on chemotherapy-induced follicle activation using a mouse model. After exposure of cut ovaries to different concentrations of VERT for 3 h, a dose-dependent effect of VERT was observed that reached significant inhibition of YAP activity at 3 µmol/L. To assess the potential effect of controlling chemotherapy-induced Hippo pathway disruption, whole mouse ovaries were exposed to VERT alone or as a co-treatment with 4-hydroperoxycylophosphamide (4HC). VERT co-treatment prevented chemotherapy-induced YAP activation but had a limited impact on downstream effector gene, Ccn2. Surprisingly, VERT co-treatment also prevented mTOR and survival signaling pathway alterations following chemotherapy exposure. These results suggest an interaction between the two main signaling pathways regulating follicle activation and a protective effect of VERT on 4HC-induced DNA damage.

Impact of Breast Cancer and Germline BRCA Pathogenic Variants on Fertility Preservation in Young Women

Impact of first chemotherapy exposure on follicle activation and survival in human cryopreserved ovarian tissue.

Does chemotherapy exposure prior to ovarian tissue cryopreservation (OTC) impact the signaling pathways governing follicle activation and survival for prepubertal and postpubertal patients?

Gene Expression Analyses in Human Follicles.

The ovary is a heterogeneous organ composed of different cell types. To study the molecular mechanisms occurring during folliculogenesis, the localization of proteins and gene expression can be performed on fixed tissue. However, to properly assess gene expression levels in a human follicle, this complex and delicate structure must be isolated. Hence, an adapted protocol previously described by Woodruff's laboratory has been developed to separate follicles (the oocyte and the granulosa cells) from their surrounding environment. The ovarian cortical tissue is first manually processed to obtain small fragments using two tools: a tissue slicer and a tissue chopper. The tissue is then enzymatically digested with 0.2% collagenase and 0.02% DNase for at least 40 min. This digestion step is performed at 37 °C and 5% CO2 and is accompanied by mechanical pipetting of the medium every 10 min. After incubation, the isolated follicles are collected manually using a calibrated microcapillary pipette under microscope magnification. If follicles are still present in the pieces of tissue, the procedure is completed with manual microdissection. The follicles are collected on ice in a culture medium and are rinsed twice in droplets of phosphate-buffered saline solution. This digestion procedure must be carefully controlled to avoid follicle deterioration. As soon as the structure of the follicles appears to be compromised or after a maximum of 90 min, the reaction is stopped with a 4 °C blocking solution containing 10% fetal bovine serum. A minimum of 20 isolated follicles (sized under 75 µm) should be collected to obtain an adequate amount of total RNA after RNA extraction for real-time quantitative polymerase chain reaction (RT-qPCR). After extraction, the quantification of total RNA from 20 follicles reaches a mean value of 5 ng/µL. The total RNA is then retrotranscribed into cDNA, and the genes of interest are further analyzed using RT-qPCR.

Impact of Anti-HER2 Therapy Alone and With Weekly Paclitaxel on the Ovarian Reserve of Young Women With HER2-Positive Breast Cancer

A selective inhibitor of the sperm-specific potassium channel SLO3 impairs human sperm function.

To fertilize an oocyte, the membrane potential of both mouse and human sperm must hyperpolarize (become more negative inside). Determining the molecular mechanisms underlying this hyperpolarization is vital for developing new contraceptive methods and detecting causes of idiopathic male infertility. In mouse sperm, hyperpolarization is caused by activation of the sperm-specific potassium (K+) channel SLO3 [C. M. Santi et al., FEBS Lett. 584, 1041-1046 (2010)]. In human sperm, it has long been unclear whether hyperpolarization depends on SLO3 or the ubiquitous K+ channel SLO1 [N. Mannowetz, N. M. Naidoo, S. A. S. Choo, J. F. Smith, P. V. Lishko, Elife 2, e01009 (2013), C. Brenker et al., Elife 3, e01438 (2014), and S. A. Mansell, S. J. Publicover, C. L. R. Barratt, S. M. Wilson, Mol. Hum. Reprod. 20, 392-408 (2014)]. In this work, we identified the first selective inhibitor for human SLO3-VU0546110-and showed that it completely blocked heterologous SLO3 currents and endogenous K+ currents in human sperm. This compound also prevented sperm from hyperpolarizing and undergoing hyperactivated motility and induced acrosome reaction, which are necessary to fertilize an egg. We conclude that SLO3 is the sole K+ channel responsible for hyperpolarization and significantly contributes to the fertilizing ability of human sperm. Moreover, SLO3 is a good candidate for contraceptive development, and mutation of this gene is a possible cause of idiopathic male infertility.

2022

Efficacy and safety of controlled ovarian hyperstimulation with or without letrozole for fertility preservation in breast cancer patients: A multicenter retrospective study

Introduction: Fertility preservation (FP) is recommended in young breast cancer (BC) patients before (neo)adjuvant treatment. Letrozole-associated controlled ovarian hyperstimulation (LetCOH) is used worldwide to collect mature oocytes for FP, but its efficacy and safety compared to conventional protocols (cCOH) are still debated. Aims: To compare efficacy and safety of FP procedure using LetCOH or cCOH in BC patients in terms of oocyte maturation rate and disease-free survival rates after at least two years of follow-up. Methods: This multicenter retrospective study compared outcomes of 107 cycles in 97 non-metastatic BC patients aged ≤40 years who underwent cCOH (n = 56) or LetCOH (n = 41) for FP in CHU-Lille and Erasme Hospital, respectively, between December 2012 and January 2017. Results: Patients and oncological characteristics were similar except for tumor size and HER2 status which were less favorable in the LetCOH group. Patients underwent adjuvant chemotherapy in 96.4% and 48.8% of the cases in cCOH and LetCOH groups, respectively. Hence, 51.2% of LetCOH patients underwent neoadjuvant chemotherapy (p < 0.001). Estradiol peak at ovulation trigger was lower in LetCOH compared to cCOH group while oocyte maturation rates were significantly higher (p < 0.001), without impacting the final number of mature oocytes collected. Seven and four patients relapsed in LetCOH and cCOH groups, respectively, and one patient died in each group after a median follow-up of four years. Conclusion: LetCOH is as effective as cCOH for FP. At this time point, there were no safety concerns regarding cCOH in the adjuvant setting but a longer follow-up is warranted.

Impact of letrozole-associated controlled ovarian hyperstimulation on ART outcomes and endocrinological parameters.

Proceedings of the Oncofertility Congress of the “Freezing Ovarian Tissue and Oocytes” (FOTO) Consortium Brussels

Impact of cancer on cryopreserved sperm quality and fertility: A cohort study

Background: Sperm quality at cancer diagnosis is often compromised by the disease and any given gonadotoxic treatment will further diminish fertility. Objectives: Here, we aim to analyze the cryopreserved sperm quality according to the cancer types as well as the fertility outcomes. Methods: Our study included all cancer patients who cryopreserved sperm over 20 years at Erasme Hospital Brussels (from 1999 to 2019). First sperm samples from 111 hematologic, 104 testicular, 19 prostate, 28 gastrointestinal, and 16 neurological cancer patients were compared. Results: Oligozoo-asthenozoospermia was observed in 30% of the samples, including 19.33% with severe oligozoospermia (<5 million/ml). Our results showed a significant reduction in sperm concentration among testicular cancer (p < 0.01). No significant differences in progressive motility, sperm volume, and number of frozen straws were observed. Significant correlations were found between sperm concentration and cancer type (p <0.01) as well as patients' age (p <0.01). Twenty-eight cancer survivors returned for using their cryopreserved sperm (9.33%), fertilization rate was 60.5% and implantation rate was 29.6%. There was no correlation between sperm concentration and fertility outcomes. Conclusion: Our results confirm the negative impact of cancer on sperm quality without affecting assisted reproductive technology (ART) success rate, which is utterly important as a male reproductive health perspective. All cancer patients should be counselled and offered fertility preservation options as a gold standard.

Risk of gonadotoxicity with immunotherapy and targeted agents remains an unsolved but crucial issue

Let-7a mimic transfection reduces chemotherapy-induced damage in a mouse ovarian transplantation model

Pharmacological approaches offer a non-invasive and promising option for fertility preservation in young female cancer patients undergoing gonadotoxic therapy. The GnRH-agonists are the only clinically available drugs in this indication, but their use and mechanisms of protection are still controversial. Recently, we have investigated new targeted drugs based on microRNA (miRNA) replacement therapy, and have identified the let-7a miRNA as candidate for fertility preservation strategies. Here, the effect of let-7a replacement during chemotherapy exposure on follicular growth and oocyte maturation capacity was investigated using a mouse ovarian-kidney transplantation model. Newborn mouse ovaries were cultured under different conditions; control, chemotherapy exposure (4-hydroperoxycyclophosphamide, 4-HC), and co-treatment with 4-HC and let-7a mimic transfection (4-HC + let-7a). The ovaries were then transplanted under the kidney capsule of recipient mice and follicular growth, survival, and oocyte in vitro maturation were assessed after 3 weeks. The results showed that the follicular pool was highest in the control group but higher in the 4-HC + let-7a group than the 4-HC group. DNA-damage/apoptosis ratios were higher in all 4-HC-exposed groups compared to control but were reduced in the 4-HC + let-7a group. In addition, the post-transplantation oocyte in vitro maturation rate was higher in the 4-HC + let-7a group compared to the 4-HC group, suggesting better oocyte quality. These results provide new information regarding the beneficial effects of let-7a replacement against chemotherapy-induced ovarian damage and open new perspectives for future in vivo applications.

Fresh and cryopreserved ovarian tissue transplantation for preserving reproductive and endocrine function: A systematic review and individual patient data meta-analysis

BACKGROUND: Ovarian tissue cryopreservation involves freezing and storing of surgically retrieved ovarian tissue in liquid or vapour nitrogen below-190°C. The tissue can be thawed and transplanted back with the aim of restoring fertility or ovarian endocrine function. The techniques for human ovarian tissue freezing and transplantation have evolved over the last 20 years, particularly in the context of fertility preservation in pre-pubertal cancer patients. Fresh ovarian tissue transplantation, using an autograft or donor tissue, is a more recent development; it has the potential to preserve fertility and hormonal function in women who have their ovaries removed for benign gynaecological conditions. The techniques of ovarian tissue cryopreservation and transplantation have progressed rapidly since inception; however, the evidence on the success of this intervention is largely based on case reports and case series. OBJECTIVE AND RATIONALE: The aim of this study was to systematically review the current evidence by incorporating study-level and individual patient-level meta-analyses of women who received ovarian transplants, including frozen-thawed transplant, fresh or donor graft. SEARCH METHODS: The review protocol was registered with PROSPERO (CRD42018115233). A comprehensive literature search was performed using MEDLINE, EMBASE, CINAHL and Cochrane Central Register of Controlled Trials from database inception to October 2020. Authors were also contacted for individual patient data if relevant outcomes were not reported in the published manuscripts. Meta-analysis was performed using inverse-variance weighting to calculate summary estimates using a fixed-effects model. OUTCOMES: The review included 87 studies (735 women). Twenty studies reported on ≥5 cases of ovarian transplants and were included in the meta-analysis (568 women). Fertility outcomes included pregnancy, live birth and miscarriage rates, and endocrine outcomes included oestrogen, FSH and LH levels. The pooled rates were 37% (95% CI: 32-43%) for pregnancy, 28% (95% CI: 24-34%) for live birth and 37% (95% CI: 30-46%) for miscarriage following frozen ovarian tissue transplantation. Pooled mean for pre-transplant oestrogen was 101.6 pmol/l (95% CI: 47.9-155.3), which increased post-transplant to 522.4 pmol/l (95% CI: 315.4-729; mean difference: 228.24; 95% CI: 180.5-276). Pooled mean of pre-transplant FSH was 66.4 IU/l (95% CI: 52.8-84), which decreased post-transplant to 14.1 IU/l (95% CI: 10.9-17.3; mean difference 61.8; 95% CI: 57-66.6). The median time to return of FSH to a value <25 IU/l was 19 weeks (interquartile range: 15-26 weeks; range: 0.4-208 weeks). The median duration of graft function was 2.5 years (interquartile range: 1.4-3.4 years; range: 0.7-5 years). The analysis demonstrated that ovarian tissue cryopreservation and transplantation could restore reproductive and hormonal functions in women. Further studies with larger samples of well-characterized populations are required to define the optimal retrieval, cryopreservation and transplantation processes. WIDER IMPLICATIONS: Ovarian tissue cryopreservation and transplantation may not only be effective in restoring fertility but also the return of reproductive endocrine function. Although this technology was developed as a fertility preservation option, it may have the scope to be considered for endocrine function preservation.

Anti-Müllerian hormone as a marker of ovarian reserve and premature ovarian insufficiency in children and women with cancer: a systematic review.

Female patients undergoing anticancer treatment are at elevated risk of adverse ovarian outcomes including infertility and premature ovarian insufficiency (POI), which is associated with short- and long-term health risks. Anti-Müllerian hormone (AMH) is a key biomarker of ovarian reserve, but its role prior to and after cancer treatment is less well understood.

A Minimal Model Shows that a Positive Feedback Loop Between sNHE and SLO3 can Control Mouse Sperm Capacitation.

When mammalian spermatozoa are released in the female reproductive tract, they are incapable of fertilizing the oocyte. They need a prolonged exposure to the alkaline medium of the female genital tract before their flagellum gets hyperactivated and the acrosome reaction can take place, allowing the sperm to interact with the oocyte. Ionic fluxes across the sperm membrane are involved in two essential aspects of capacitation: the increase in intracellular pH and the membrane hyperpolarization. In particular, it has been shown that the SLO3 potassium channel and the sNHE sodium-proton exchanger, two sperm-specific transmembrane proteins, are necessary for the capacitation process to occur. As the SLO3 channel is activated by an increase in intracellular pH and sNHE is activated by hyperpolarization, they act together as a positive feedback system. Mathematical modeling provides a unique tool to capture the essence of a molecular mechanism and can be used to derive insight from the existing data. We have therefore developed a theoretical model formalizing the positive feedback loop between SLO3 and sHNE in mouse epididymal sperm to see if this non-linear interaction can provide the core mechanism explaining the existence of uncapacited and capacitated states. We show that the proposed model can fully explain the switch between the uncapacitated and capacited states and also predicts the existence of a bistable behaviour. Furthermore, our model indicates that SLO3 inhibition, above a certain threshold, can be effective to completely abolish capacitation.

First live birth after fertility preservation using vitrification of oocytes in a woman with mosaic Turner syndrome.

To report the case of a young woman diagnosed with Turner syndrome (TS) who achieved a live birth using her own oocytes that had been vitrified for fertility preservation.

Ovarian toxicity of carboplatin and paclitaxel in mouse carriers of mutation in BRIP1 tumor suppressor gene.

More than 10% of women diagnosed with breast cancer during reproductive age carry hereditary germline pathogenic variants in high-penetrance BRCA genes or in others genes involved in DNA repair mechanisms such as PALB2, BRIP or ATM. Anticancer treatments may have an additional negative impact on the ovarian reserve and subsequently on the fertility of young patients carrying such mutations. Recently, the combination of carboplatin and paclitaxel is being recommended to these BRCA-mutated patients as neoadjuvant therapy. However, the impact on the ovary is unknown. Here, we investigated their effect of on the ovarian reserve using mice carriers of BRCA1-interacting protein C-terminal helicase-1 (BRIP1) mutation that plays an important role in BRCA1-dependent DNA repair. Results revealed that the administration of carboplatin or paclitaxel did not affect the ovarian reserve although increased DNA double-strand breaks were observed with carboplatin alone. Co-administration of carboplatin and paclitaxel resulted in a significant reduction of the ovarian reserve leading to a lower IVF performance, and an activation of the PI3K-Pten pathway, irrespective of the genetic background. This study suggests that co-administration of carboplatin and paclitaxel induces cumulative ovarian damage and infertility but a heterozygote genetic predisposition for DNA damage related to BRCA1 gene function does not increase this risk.

Safety of fertility preservation techniques before and after anticancer treatments in young women with breast cancer: a systematic review and meta-analysis.

Is it safe to perform controlled ovarian stimulation (COS) for fertility preservation before starting anticancer therapies or ART after treatments in young breast cancer patients?

A retrospective study evaluating the impact of scattering radiation from imaging procedures on oocyte quality during ovarian stimulation for fertility preservation in young breast cancer patients.

Ovarian stimulation for oocyte and embryo cryopreservation is the standard of care for fertility preservation in young breast cancer patients before gonadotoxic chemotherapy. The procedure should be started as soon as possible to avoid delay of treatment; thus, it is often performed concomitantly with tumor staging assessments. However, questions remain regarding the potential negative impact on oocyte quality that may occur due to exposure to scattered ionizing radiation from imaging techniques when staging assessment is conducted at the same time as ovarian stimulation.

PTPN2 Regulates the Interferon Signaling and Endoplasmic Reticulum Stress Response in Pancreatic Beta-Cells in Autoimmune Diabetes.

Type 1 diabetes (T1D) results from autoimmune destruction of β-cells in the pancreas. Protein tyrosine phosphatases (PTPs) are candidate genes for T1D and play a key role in autoimmune disease development and β-cell dysfunction. Here, we assessed the global protein and individual PTP profiles in the pancreas from early onset non-obese diabetic (NOD) mice treated with an anti-CD3 monoclonal antibody and interleukin-1 receptor antagonist. The treatment reversed hyperglycemia and we observed enhanced expression of PTPN2, a PTP family member and T1D candidate gene, and endoplasmic reticulum (ER) chaperones in the pancreatic islets. To address the functional role of PTPN2 in β-cells, we generated PTPN2-deficient human stem cell-derived β-like and EndoC-βH1 cells. Mechanistically, we demonstrated that PTPN2 inactivation in β-cells exacerbates type I and type II interferon signaling networks and the potential progression towards autoimmunity. Moreover, we established the capacity of PTPN2 to positively modulate the Ca2+-dependent unfolded protein response and ER stress outcome in β-cells. Adenovirus-induced overexpression of PTPN2 partially protected from ER-stress induced β-cell death. Our results postulate PTPN2 as a key protective factor in β-cells during inflammation and ER stress in autoimmune diabetes.

2021

Safety of assisted reproductive techniques in young women harboring germline pathogenic variants in BRCA1/2 with a pregnancy after prior history of breast cancer.

Knowledge is growing on the safety of assisted reproductive techniques (ART) in cancer survivors. No data exist, however, for the specific population of breast cancer patients harboring germline BRCA1/2 pathogenic variants.

Circulating Tumor DNA to Interrogate the Safety of Letrozole-Associated Controlled Ovarian Stimulation for Fertility Preservation in Breast Cancer Patients.

Current fertility preservation strategies for young breast cancer patients planning a future motherhood include the association of controlled ovarian stimulation with the aromatase inhibitor letrozole (let-COS) to harvest mature oocytes while maintaining low estradiol levels. Despite this is a widely adopted protocol, the safety of let-COS on breast cancer outcomes has been poorly investigated and its use remains off-label. We assessed the safety of let-COS in breast cancer patients using circulating tumor DNA (ctDNA) as a surrogate biomarker of disease recurrence.

Risk of contamination of semen, vaginal secretions, follicular fluid and ovarian medulla with SARS-CoV-2 in patients undergoing ART

Abstract Study question Can SARS-CoV-2 mRNA be detected in the reproductive tract of asymptomatic patients undergoing ART? Summary answer SARS-CoV-2 mRNA is not detectable in semen, follicular fluid, vaginal secretions or residual medulla from ovarian tissue cryopreservation procedures in asymptomatic patients who undergo ART, irrespective of the results of a triage questionnaire and a nasopharyngeal SARS-CoV-2 RNA detection test. What is known already The SARS-CoV-2 pandemic had a huge impact on the activities of fertility clinics. Although some studies reported the presence of SARS-CoV-2 mRNA in the reproductive system during or after acute COVID-19 symptomatic infections, uncertainties remain regarding the presence of viral mRNA in the reproductive material and follicular fluid of asymptomatic patients undergoing ART. Study design, size, duration An observational cohort trial of residual material samples including semen, follicular fluid, vaginal secretions and ovarian medulla was conducted during the second pandemic wave in Brussels, from September, 2020 to April, 2021. Participants/materials, setting, methods All patients who underwent ART (IIU, IVF/ICSI, oocyte and ovarian tissue cryopreservation) responded to a triage questionnaire at the beginning and end of the cycle and underwent nasopharyngeal swab collection for SARS-CoV-2 RNA detection by RT-PCR before the procedure according to standard recommendations. For semen analysis, only the questionnaire was requested the day before the sample collection. The ART cycles of patients with positive nasopharyngeal SARS-CoV-2 RNA detection tests and/or questionnaires were canceled except for those that could not be postponed. After providing informed consent, swabs on residual materials were collected the day of the oocyte, ovarian tissue or semen collection and were processed for RT-qPCR. Main results and the role of chance A total of 394 samples from 291 patients were analysed. Amongst them, 20 samples were obtained from patients with a positive questionnaire but negative nasopharyngeal SARS-CoV-2 test and 20 others were from patients with a positive nasopharyngeal SARS-CoV-2 test. The remaining samples were collected from patients with a negative or unknown nasopharyngeal SARS-CoV-2 test and/or a negative or unknown triage questionnaire. Viral RNA for SARS-CoV-2 was undetectable in all of the samples. Limitations, reasons for caution Considering the cancellation policy, only a limited number of samples from patients with positive triage questionnaires or nasopharyngeal SARS-CoV-2 tests were included in the analysis. Wider implications of the findings The study suggested that there was no risk of reproductive tract contamination by SARS-CoV-2 in asymptomatic patients, irrespective of the results from a triage questionnaire or nasopharyngeal SARS-CoV-2 test. The results suggested that no additional measures to prevent staff or cross-patient contamination need to be implemented in the IVF and andrology laboratories. Study funding/competing interest(s) This study was funded by Université Libre de Bruxelles and by a grant from Ferring. AD and ID received a grant from Ferring for the study. The authors have no other conflict of interest to declare related to this study.

Pregnancy After Breast Cancer: A Systematic Review and Meta-Analysis

PURPOSE: Many patients and physicians remain concerned about the potential detrimental effects of pregnancy after breast cancer (BC) in terms of reproductive outcomes and maternal safety. This systematic review and meta-analysis aimed at providing updated evidence on these topics. METHODS: A systematic literature review was conducted to identify studies including patients with a pregnancy after BC (PROSPERO number CRD42020158324). Likelihood of pregnancy after BC, their reproductive outcomes, and maternal safety were assessed. Pooled relative risks, odds ratios (ORs), and hazard ratios (HRs) with 95% CIs were calculated using random effects models. RESULTS: Of 6,462 identified records, 39 were included involving 8,093,401 women from the general population and 112,840 patients with BC of whom 7,505 had a pregnancy after diagnosis. BC survivors were significantly less likely to have a subsequent pregnancy compared with the general population (relative risk, 0.40; 95% CI, 0.32 to 0.49). Risks of caesarean section (OR, 1.14; 95% CI, 1.04 to 1.25), low birth weight (OR, 1.50; 95% CI, 1.31 to 1.73), preterm birth (OR, 1.45; 95% CI, 1.11 to 1.88), and small for gestational age (OR, 1.16; 95% CI, 1.01 to 1.33) were significantly higher in BC survivors, particularly in those with previous chemotherapy exposure, compared with the general population. No significantly increased risk of congenital abnormalities or other reproductive complications were observed. Compared to patients with BC without subsequent pregnancy, those with a pregnancy had better disease-free survival (HR, 0.66; 95% CI, 0.49 to 0.89) and overall survival (HR, 0.56; 95% CI, 0.45 to 0.68). Similar results were observed after correcting for potential confounders and irrespective of patient, tumor, and treatment characteristics, pregnancy outcome, and timing of pregnancy. CONCLUSION: These results provide reassuring evidence on the safety of conceiving in BC survivors. Patients' pregnancy desire should be considered a crucial component of their survivorship care plan.

Gonadal Function Recovery in Patients With Advanced Hodgkin Lymphoma Treated With a PET-Adapted Regimen: Prospective Analysis of a Randomized Phase III Trial (AHL2011)

PURPOSE: The prospective, randomized AHL2011 trial demonstrated that the use of the doxorubicin, bleomycin, vinblastine, and dacarbazine regimen (ABVD) after two cycles of bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPPescalated) in early responders on the basis of a positron emission tomography (PET)-driven strategy was safe and minimized toxicity compared with standard 6 BEACOPPescalated cycles. This substudy investigated the benefit of this strategy in gonadal function and fertility in patients under 45 years old. METHODS: Ovarian function was assessed by serum measurement of follicle-stimulating hormone (FSH), estradiol, and anti-müllerian hormone in women, and semen analysis, FSH, and testosterone levels were used to evaluate testicular function in men at baseline, end of treatment, and during 5 years of follow-up. RESULTS: A total of 145 women and 424 men, enrolled between May 19, 2011, and April 29, 2014, were included. The risk of premature ovarian insufficiency (FSH > 24 IU/L) and of having a low ovarian reserve (anti-müllerian hormone < 0.5 ng/mL) was reduced after treatment in the PET-driven group (odds ratio [OR], 0.20; 95% CI, 0.08 to 0.50; P = .001 and OR, 0.15; 95% CI, 0.04 to 0.56, P = .005, respectively). Both parameters were correlated with age and dose of alkylating agents. However, no significant differences were observed in terms of pregnancy rates. Men in the PET-driven group had a higher recovery rate of sperm parameters after treatment compared with the standard BEACOPPescalated group, as well as a lower risk of severe testicular damage (OR, 0.26; 95% CI, 0.13 to 0.5; P < .0001) and a higher likelihood of achieving pregnancy (OR, 3.7; 95% CI, 1.4 to 9.3; P = .004). CONCLUSION: Although both treatments affected ovarian reserve and spermatogenesis, the PET-driven strategy decreased the risk of gonadal dysfunction and infertility in advanced Hodgkin lymphoma.

Association of Germline BRCA Pathogenic Variants With Diminished Ovarian Reserve: A Meta-Analysis of Individual Patient-Level Data.

To determine whether germline BRCA (gBRCA) pathogenic variants are associated with decreased ovarian reserve.

Ovarian tissue cryopreservation and transplantation in patients with central nervous system tumours.

Is there a possibility of reseeding cancer cells potentially present in frozen ovarian tissue from patients with central nervous system (CNS) tumours?

Cancer survivorship: Reproductive health outcomes should be included in standard toxicity assessments

It is well established that cancer and its treatment, whether by chemotherapy, radiotherapy, hormone therapy, or surgery, can adversely impact reproductive function in both women and men. The effects of cancer treatment on reproductive function in both sexes may lead to loss of fertility, sexual desire and function, and hormone deficiency, which results in additional long-term morbidity in more than a third of patients. Given the importance of reproductive function to most people, and the often devastating effect of cancer treatment on it, we propose that proactive assessment of the functional and endocrinological impact of treatment be made a vital component of the assessment of modern cancer treatment, and should be a routine part of discussions with patients before and after treatment, both in trials and in routine care. Reproductive counselling should be proactive and encouraged, as implementation of such counselling has been shown to be beneficial to patient mental health, quality of life, and adherence to treatment. Similarly, efforts should be made to provide more adequate and accurate information to patients, as well as to offer appropriate fertility preservation approaches, which may potentially influence their treatment decisions.

Impact of ARTs on oncological outcomes in young breast cancer survivors

Abstract STUDY QUESTION What is the risk of recurrence in young breast cancer survivors who undergo ARTs following completion of anticancer treatment? SUMMARY ANSWER ART in breast cancer survivors does not appear to have a negative impact on disease-free survival. WHAT IS KNOWN ALREADY In healthy women, fertility treatment does not increase the risk of developing breast cancer. At the time of breast cancer diagnosis and before starting anticancer treatments, several studies have shown the safety of performing ART. However, the safety of ART in breast cancer survivors following completion of anticancer treatment remains under-investigated. In general, breast cancer survivors are counselled to avoid any hormonal treatment but there are limited data available on the effect of short exposure to high oestradiol levels during ART. The largest study in this regard included 25 breast cancer survivors exposed to ART and did not show a detrimental effect of ART on patient survival. Hence, taking into account that pregnancy after breast cancer does not affect cancer prognosis, defining the safety of ART in breast cancer survivors remains a priority. STUDY DESIGN, SIZE, DURATION We conducted a retrospective multicentric matched cohort study including a cohort of breast cancer survivors who underwent ART (exposed patients) between January 2006 and December 2016. Exposed patients who were eligible for the study were matched according to known breast cancer prognostic factors. Matched breast cancer survivors did not undergo ART (non-exposed patients) and were disease-free for a minimum time that was not less than the time elapsed between breast cancer diagnosis and first ART for the matched ART-exposed patients. PARTICIPANTS/MATERIALS, SETTING, METHODS Data were retrieved from all survivors who had been diagnosed with breast cancer in eight participating centres at an age of ≤40 years, without metastasis, ongoing pregnancy, pre-existing neoplasia or ovarian failure. ART included ovarian stimulation for IVF/ICSI, clomiphene citrate treatment and hormone replacement therapy for embryo transfer. Data were collected from an oncological database for the selection of breast cancer patients in the non-exposed group. Exposed patients were matched (1:2) for germline BRCA status, tumour stage, anticancer treatment and age, whenever feasible. Matched groups were compared at baseline according to characteristics using conditional logistic regression. Kaplan-Meier curves were constructed to compare time to recurrence between groups, with the time of ART as starting point that has been adjusted in the non-exposed group. The analyses were performed using Stata IC/15.1. MAIN RESULTS AND THE ROLE OF CHANCE A total of 39 breast cancer patients in the ART group were eligible for the analysis and were matched with 73 controls. There was no statistical difference between the two groups for the presence of BRCA mutation, tumour characteristics, use of (neo)adjuvant chemotherapy and of adjuvant endocrine therapy. Exposed patients were younger than non-exposed patients (mean age 31.8 vs 34.3 years, respectively; P &lt; 0.001). In the ART group, 89.7% were nulliparous at diagnosis compared to 46.6% of controls (P &lt; 0.001). ART was performed at a mean age of 37.1 years old, after a median time of 4.1 years following breast cancer diagnosis (range: 1.5-12.5). Median anti-Müllerian hormone at the time of ART was 0.28 ng/ml (range: 0-4.4) and median serum oestradiol peak level was 696.5 pg/ml (range: 139.7-4130). Median follow-up time from first attempt of ART was 4.6 years (range: 2.4-12.5) in the ART group. Adjusted follow-up time for the non-exposed group was 6.9 years (range: 1.1-16.5 years) (P = 0.004). In the ART group, 59% of patients had a pregnancy after breast cancer compared to 26% in the non-exposed patients (P = 0.001). Breast cancer relapsed in 7.7% versus 20.5% women in the ART and non-exposed groups, respectively (hazard ratio 0.46, 95% CI 0.13-1.62, P = 0.23). Median time to relapse was 1.3 (range: 0.3-2.7) years versus 4.5 (range: 0.4-11.1) years after ART and adjusted time in the ART and non-exposed groups, respectively (P = 0.14). LIMITATIONS, REASONS FOR CAUTION Although this is the first and largest multicentric study addressing the impact of ART on breast cancer recurrence to provide data on oestrogen exposure, only a small number of patients could be included. This reflects the reluctance of breast cancer survivors and/or oncologists to perform ART, and highlights the need for a prospective data registry to confirm the safety of this approach. This would offer the possibility for these patients, who are at a high risk of infertility, to fully benefit from ART. WIDER IMPLICATIONS OF THE FINDINGS Although recent studies have proven that pregnancy after breast cancer has no detrimental impact on prognosis, counselling patients about the safety of ART remains challenging. Our study provides reassuring data on the use of ART in breast cancer survivors with favourable prognostic factors, for when natural conception fails. STUDY FUNDING/COMPETING INTEREST(S) M.C. and I.D. are funded by FNRS, Télévie-FNRS and Fonds Erasme. M.D.V. is a CooperSurgical scientific advisory board member and receives lecture fees for MSD, Gedeon-Richter and Ferring, outside the submitted work. M.L. has acted as a consultant for Roche and Novartis and has received honoraria from Theramex, Roche, Lilly, Pfizer, Novartis and Takeda, outside the submitted work. I.D. has acted as a consultant for ROCHE and has received speaker's fees from Novartis, outside the submitted work. E.d.A. has received honoraria and is a Roche/GNE, Novartis, SeaGen and Zodiac scientific advisory board member, has received travel grants from Roche/GNE and GSK/Novartis, and has received research grants from Roche/GNE, Astra-Zeneca, GSK/Novartis and Servier, outside the submitted work. A.D. is a recipient of a research grant from Ferring Pharmaceuticals and receives lecture and/or consultancy fees from Merck, Gedeon-Richter and Ferring Pharmaceuticals, outside the submitted work. The remaining authors have no conflicts of interest to declare. TRIAL REGISTRATION NUMBER N/A.

Fertility preservation for female patients with childhood, adolescent, and young adult cancer: recommendations from the PanCareLIFE Consortium and the International Late Effects of Childhood Cancer Guideline Harmonization Group.

Female patients with childhood, adolescent, and young adult cancer are at increased risk for fertility impairment when treatment adversely affects the function of reproductive organs. Patients and their families desire biological children but substantial variations in clinical practice guidelines reduce consistent and timely implementation of effective interventions for fertility preservation across institutions. As part of the PanCareLIFE Consortium, and in collaboration with the International Late Effects of Childhood Cancer Guideline Harmonization Group, we reviewed the current literature and developed a clinical practice guideline for fertility preservation in female patients who were diagnosed with childhood, adolescent, and young adult cancer at age 25 years or younger, including guidance on risk assessment and available methods for fertility preservation. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to grade the available evidence and to form the recommendations. This clinical practice guideline leverages existing evidence and international expertise to develop transparent recommendations that are easy to use to facilitate the care of female patients with childhood, adolescent, and young adult cancer who are at high risk for fertility impairment. A complete review of the existing evidence, including a quality assessment, transparent reporting of the guideline panel's decisions, and achievement of global interdisciplinary consensus, is an important result of this intensive collaboration.

Installing oncofertility programs for common cancers in optimum resource settings (Repro-Can-OPEN Study Part II): a committee opinion.

The main objective of Repro-Can-OPEN Study Part 2 is to learn more about oncofertility practices in optimum resource settings to provide a roadmap to establish oncofertility best practice models.

Conserved Mechanism of Bicarbonate-Induced Sensitization of CatSper Channels in Human and Mouse Sperm.

To fertilize an egg, mammalian sperm must undergo capacitation in the female genital tract. A key contributor to capacitation is the calcium (Ca2+) channel CatSper, which is activated by membrane depolarization and intracellular alkalinization. In mouse epididymal sperm, membrane depolarization by exposure to high KCl triggers Ca2+ entry through CatSper only in alkaline conditions (pH 8.6) or after in vitro incubation with bicarbonate (HCO3 -) and bovine serum albumin (capacitating conditions). However, in ejaculated human sperm, membrane depolarization triggers Ca2+ entry through CatSper in non-capacitating conditions and at lower pH (< pH 7.4) than is required in mouse sperm. Here, we aimed to determine the mechanism(s) by which CatSper is activated in mouse and human sperm. We exposed ejaculated mouse and human sperm to high KCl to depolarize the membrane and found that intracellular Ca2+ concentration increased at pH 7.4 in sperm from both species. Conversely, intracellular Ca2+ concentration did not increase under these conditions in mouse epididymal or human epididymal sperm. Furthermore, pre-incubation with HCO3 - triggered an intracellular Ca2+ concentration increase in response to KCl in human epididymal sperm. Treatment with protein kinase A (PKA) inhibitors during exposure to HCO3 - inhibited Ca2+ concentration increases in mouse epididymal sperm and in both mouse and human ejaculated sperm. Finally, we show that soluble adenylyl cyclase and increased intracellular pH are required for the intracellular Ca2+ concentration increase in both human and mouse sperm. In summary, our results suggest that a conserved mechanism of activation of CatSper channels is present in both human and mouse sperm. In this mechanism, HCO3 - in semen activates the soluble adenylyl cyclase/protein kinase A pathway, which leads to increased intracellular pH and sensitizes CatSper channels to respond to membrane depolarization to allow Ca2+ influx. This indirect mechanism of CatSper sensitization might be an early event capacitation that occurs as soon as the sperm contact the semen.