Effects of PD-1 blockade on ovarian follicles in a prepubertal female mouse

Immune system regulation of physiological and pathological aspects of the ovarian follicle pool throughout the female reproductive lifespan

The immune system plays a major role in ovarian physiology by regulating the ovarian follicle pool through complex signaling of different growth factors, cytokines, and chemokines. These may promote follicle activation and further growth but could also trigger follicle atresia and clearance of aging or damaged cells within the ovarian cortex. Moreover, extraglandular steroidogenesis potentially occurring in different immune cells like macrophages and natural killer cells might be another way of modulating follicle growth. Ovarian macrophages have recently been found to contain two different populations, namely resident macrophages and monocyte-derived cells, with potentially different roles. The immune system also plays a role in the development of pathological conditions, including premature ovarian insufficiency (POI). Indeed, autoimmune activation against various ovarian antigen targets results in lymphocytic oophoritis mainly targeting early growing follicles, but later leading to complete follicle pool depletion. Immune-mediated ovarian damage may also be caused by viral infection or be the consequence of iatrogenic damage. Certain novel cancer immunotherapies like checkpoint inhibitors have recently been shown to induce ovarian reserve damage in a murine model. Studies are needed to corroborate these findings and further investigate the potential of newly developed immunotherapies to treat POI. Technological advances such as single-cell analyses of less represented cell populations like immune cells inside the ovary are now contributing to valuable new information, which will hopefully lead to the development of new therapeutic strategies for women with fertility issues.

Fertility outcomes post immune checkpoint inhibitor exposure

Harrold et al. evaluate the fertility impact of checkpoint inhibitor blockade (ICB), demonstrating that unlike in utero exposure, post-exposure conception appears to result in uncomplicated pregnancies and healthy progeny. They demonstrate contemporaneous monitoring of temporal female hormonal fluctuations before, on, and post ICB exposure and prior to successful embryo implantation.

The Effects of Cancer Immunotherapy on Fertility: Focus on Hematological Malignancies

In recent years, cancer management has benefitted from new effective treatments, including immunotherapy. While these therapies improve cancer survival rates, they can alter immune responses and cause long-term side effects, of which gonadotoxic effects and the potential impact on male and female fertility are growing concerns. Immunotherapies, such as immune checkpoint inhibitors, immunomodulators, monoclonal antibodies, and CAR-T, can lead to elevated levels of proinflammatory cytokines and immune-related adverse events that may exacerbate fertility problems. Immunotherapy-related inflammation, characterized by cytokine imbalances and the activation of pathways such as AMPK/mTOR, has been implicated in the mechanisms of fertility impairment. In men, hypospermatogenesis and aspermatogenesis have been observed after treatment with immune checkpoint inhibitors, by direct effects on the gonads, particularly through the inhibition of cytotoxic T lymphocyte antigen-4. In women, both damage to ovarian reserves, recurrent pregnancy loss, and implantation failure have been documented, secondary to a complex interplay between immune cells, such as T cells and uterine NK cells. In this review, the impact of immunotherapy on fertility in patients with hematological cancers was analyzed. While this area is still underexplored, fertility preservation methods remain crucial. Future studies should investigate immunotherapy's effects on fertility and establish standardized preservation protocols.

Pediatric Cancer Immunotherapy and Potential for Impact on Fertility: A Need for Evidence-Based Guidance

The use of immunotherapies for the treatment of cancer in children, adolescents, and young adults has become common. As the use of immunotherapy has expanded, including in earlier lines of therapy, it has become evident that several aspects of how these immunotherapies impact longer-term outcomes among survivors are understudied. Traditional cancer therapies like alkylating and platin agents carry the greatest risk of infertility, but little is known about the impact of novel immunotherapies on fertility. This topic is of great interest to patients, patient advocates, and clinicians. In this article, we review immunotherapeutic agents used to treat childhood and young adult cancers and discuss potential mechanisms by which they may impact fertility based on the known interplay between the immune system and reproductive organs. We highlight the relative paucity of high-quality literature examining these late effects. We discuss interventions to optimize fertility preservation (FP) for our patients. Conducting longitudinal, collaborative, and prospective research on the fertility outcomes of pediatric and young adult patients with cancer who receive immunotherapy is critical to learn how to effectively counsel our patients on long-term fertility outcomes and indications for FP procedures. Collection of patient-level data will be necessary to draft evidence-based guidelines on which providers can make therapy recommendations.

Conditional loss of Brca1 in oocytes causes reduced litter size, ovarian reserve depletion and impaired oocyte in vitro maturation with advanced reproductive age in mice

BACKGROUND

An estimated 1 in 350 women carry germline BRCA1/2 mutations, which confer an increased risk of developing breast and ovarian cancer, and may also contribute to subfertility. All mature, sex steroid-producing ovarian follicles are drawn from the pool of non-renewable primordial follicles, termed the 'ovarian reserve'. The clinical implications of early ovarian reserve exhaustion extend beyond infertility, to include the long-term adverse health consequences of loss of endocrine function and premature menopause. We aimed to determine whether conditional loss of Brca1 in oocytes impacts ovarian follicle numbers, oocyte quality and fertility in mice with advancing maternal age. We also aimed to determine the utility of AMH as a marker of ovarian function, by assessing circulating AMH levels in mice and women with BRCA1/2 mutations, and correlating this with ovarian follicle counts.

METHODS

In this study, we addressed a longstanding question in the field regarding the functional consequences of BRCA1 inactivation in oocytes. To recapitulate loss of BRCA1 protein function in oocytes, we generated mice with conditional gene deletion of Brca1 in oocytes using Gdf9-Cre recombinase (WT: Brca1fl/flGdf9+/+; cKO: Brca1fl/flGdf9cre/+).

FINDINGS

While the length of the fertile lifespan was not altered between groups after a comprehensive breeding trial, conditional loss of Brca1 in oocytes led to reduced litter size in female mice. Brca1 cKO animals had a reduced ovarian reserve and oocyte maturation was impaired with advanced maternal age at postnatal day (PN)300, compared to WT animals. Serum anti-Müllerian hormone (AMH) concentrations (the gold-standard indirect marker of the ovarian reserve used in clinical practice) were not predictive of reduced primordial follicle number in Brca1 cKO mice versus WT. Furthermore, we found no correlation between follicle number or density and serum AMH concentrations in matched samples from a small cohort of premenopausal women with BRCA1/2 mutations.

INTERPRETATION

Together, our data demonstrate that BRCA1 is a key regulator of oocyte number and quality in females and suggest that caution should be used in relying on AMH as a reliable marker of the ovarian reserve in this context.

FUNDING

This work was made possible through Victorian State Government Operational Infrastructure Support and Australian Government NHMRC IRIISS. This work was supported by funding from the Australian Research Council (ALW - DE21010037 and KJH - FT190100265), as well as the National Breast Cancer Foundation (IIRS-22-092) awarded to ALW and KJH. LRA, YML, LT, EOKS and MG were supported by Australian Government Research Training Program Scholarships. LRA, YML and LT were also supported by a Monash Graduate Excellence Scholarship. YC, SG and XC were supported by Monash Biomedicine Discovery Institute PhD Scholarships. LRA was also supported by a Monash University ECPF24-6809920940 Fellowship. JMS was supported by NHMRC funding (2011299). MH was supported by an NHMRC Investigator Grant (1193838).

Assessing risks and knowledge gaps on the impact of systemic therapies in early breast cancer on female fertility: A systematic review of the literature

The therapeutic landscape for early breast cancer (eBC) has expanded by introducing novel anticancer agents into clinical practice. During their reproductive years, women with eBC should be informed of the potential risk of premature ovarian insufficiency (POI) and infertility with the proposed systemic therapy. Although the topic of female fertility is becoming increasingly relevant in patients with cancer, limited information is available on the gonadotoxicity of new agents available for eBC treatment. Analyses from clinical trials and prospective data on ovarian function biomarkers are lacking. The purpose of this systematic review is to report the available preclinical and clinical data on female fertility risk with the use of the new agents that are part of clinical practice use or under development for eBC management. This review highlights the clear need to perform additional research efforts to improve our understanding on the gonoadtoxicity of new anticancer agents.

Bioinformatic analysis of the role of immune checkpoint genes and immune infiltration in the pathogenesis and development of premature ovarian insufficiency

PURPOSE

With advances in immunology, increasing evidence suggests that immunity is involved in premature ovarian insufficiency (POI) pathogenesis. This study investigated the roles of immune checkpoint genes and immune cell infiltration in POI pathogenesis and development.

METHODS

The GSE39501 dataset and immune checkpoint genes were obtained from the Gene Expression Omnibus database and related literature. The two datasets were intersected to obtain immune checkpoint-related differentially expressed genes (ICRDEGs), which were analyzed using Gene Ontology and Kyoto Encyclopedia of Gene and Genomes enrichment analysis, weighted correlation network analysis, protein-protein interaction and related microRNAs, transcription factors, and RNA binding proteins. The immune cell infiltration of ICRDEGs was explored, and receiver operating characteristic curves were used to validate the diagnostic value of ICRDEGs in POI.

RESULTS

We performed ICRDEG functional enrichment analysis and found that these genes were closely related to immune processes, such as T cell activation. Specifically, they are enriched in various biological processes and pathways, such as cell adhesion molecule and T cell receptor signaling pathways. Weighted correlation network analysis identified seven hub genes: Cd200, Cd274, Cd28, neurociliary protein-1, Cd276, Cd40lg, and Cd47. Furthermore, we identified 112 microRNAs, 17 RNA-binding proteins, and 101 transcription factors. Finally, immune infiltration analysis showed a clear positive correlation between hub genes and multiple immune cell types.

CONCLUSION

Bioinformatic analysis identified seven potential ICRDEGs associated with POI, among which the immune checkpoint molecules CD200 and neurociliary protein-1 may be involved in the pathogenesis of POI.

Fertility Preservation in the Era of Immuno-Oncology: Lights and Shadows

In recent years, immuno-oncology has revolutionized the cancer treatment field by harnessing the immune system's power to counteract cancer cells. While this innovative approach holds great promise for improving cancer outcomes, it also raises important considerations related to fertility and reproductive toxicity. In fact, most young females receiving gonadotoxic anti-cancer treatments undergo iatrogenic ovarian exhaustion, resulting in a permanent illness that precludes the vocation of motherhood as a natural female sexual identity. Although commonly used, oocyte cryopreservation for future in vitro fertilization and even ovarian cortex transplantation are considered unsafe procedures in cancer patients due to their oncogenic risks; whereas, ovarian stem cells might support neo-oogenesis, providing a novel stemness model of regenerative medicine for future fertility preservation programs in oncology. Recent scientific evidence has postulated that immune checkpoint inhibitors (ICIs) might in some way reduce fertility by inducing either primary or secondary hypogonadism, whose incidence and mechanisms are not yet known. Therefore, considering the lack of data, it is currently not possible to define the most suitable FP procedure for young patients who are candidates for ICIs. In this report, we will investigate the few available data concerning the molecular regulation of ICI therapy and their resulting gonadal toxicity, to hypothesize the most suitable fertility preservation strategy for patients receiving these drugs.

Survivorship outcomes in patients treated with immune checkpoint inhibitors: a scoping review

BACKGROUND

Immune checkpoint inhibitors (ICIs) have become a central part of cancer care. However, the survivorship outcomes in patients treated with ICIs are understudied. Therefore, we conducted a scoping review to evaluate the current status of the field and to establish research gaps regarding survivorship outcomes with ICIs in real-life cohorts.

METHODS

We used the Web of Science, PubMed, and Embase databases to systematically filter published studies with real-life cohorts from January 1, 2010, until October 19, 2022. Studies evaluating at least one survivorship outcome in ICI-treated patients were included.

RESULTS

A total of 39 papers were included. Quality of life (QoL) (n = 23), toxicity burden (n = 16), and psychosocial issues (n = 9) were the most frequently evaluated survivorship outcomes. Anti-PD-1/PD-L1 monotherapy and a response to treatment were associated with better QoL. In addition, the ICIs were associated with grade 3 or higher immune-related adverse events (irAEs) in 10-15% and late/long-term irAEs in 20-30% of the survivors. Regarding psychosocial problems, over 30% of survivors showed evidence of anxiety and depression, and 30-40% of survivors reported neurocognitive impairments.

CONCLUSION

The survivors treated with ICIs have impairments in most survivorship domains. Further research is needed to gather data on the understudied survivorship outcomes like late and long-term effects, fertility, financial toxicity, and return to work in survivors treated with ICIs.

IMPLICATIONS FOR CANCER SURVIVORS

Available evidence demonstrates that a significant portion of survivors treated with ICIs have a significant toxicity burden, lower QoL than the general population, and a high rate of psychosocial problems.

Immune Checkpoint Inhibitors as A Threat to Reproductive Function: A Systematic Review

In recent years, the indications for immunotherapy in cancer treatment have been expanding. The increased risk of cancer in young people, coupled with the fact that many women or men choose to delay childbearing, has made an increasing number of patients of childbearing age eligible for immunotherapy. Furthermore, with the improvements of various treatments, more young people and children are able to survive cancer. As a result, long-term sequelae of cancer treatments, such as reproductive dysfunction, are increasingly important for survivors. While many anti-cancer drugs are known to cause reproduction dysfunction, the effects of immune checkpoint inhibitors (ICIs) on reproduction function remain largely unknown. Through a retrospective analysis of previous reports and literature, this article aims to elucidate the causes of reproductive dysfunction induced by ICIs and focus on their specific mechanisms, in order to providing some guidance to clinicians and patients.

Primary ovarian insufficiency secondary to chemotherapy with inotuzumab ozogamicin and other agents

Recent advances in targeted therapy with monoclonal antibodies have significantly improved outcomes for people with cancer, sometimes allowing patients to avoid ovotoxic agents altogether. The current understanding is that monoclonal antibody cancer therapies that are not targeted to ovarian antigens should not impact ovarian reserve or increase the risk of primary ovarian insufficiency (POI). We present a case of rapid onset POI in a 23-year-old patient following chemotherapy for relapse/refractory B-cell acute lymphoblastic leukemia with a monoclonal antibody drug-conjugate, inotuzumab ozogamicin, that targets CD22. She was also treated with intrathecal methotrexate, cytarabine, and vincristine which are typically considered low risk for ovotoxicity. She was ovulatory with an AMH of 1.0 ng/mL prior to treatment and 2 months later was found to have an undetectable AMH. The patient experienced a canceled fertility preservation cycle due to an absent response to gonadotropins during ovarian stimulation. Consideration should be given to potential gonadal effects of monoclonal antibody therapies that may not have previously been explored.