Female Oncofertility: Current Understandings, Therapeutic Approaches, Controversies, and Future Perspectives

Intravenous administration of mitochondria improves ovarian function by anti-apoptosis in the premature ovarian insufficiency model

OBJECTIVE

For patients with contraindications to hormone therapy, the absence of effective treatments for ovarian dysfunction post chemotherapy represents a critical issue requiring resolution. Local administration of mitochondria may enhance ovarian function in premature ovarian insufficiency (POI) by ameliorating diminished mitochondrial activity. Nevertheless, there is a paucity of literature on the efficacy of mitochondrial transplantation through intravenous injection, a less invasive and more convenient method than local injection, for the improvement of ovarian function in POI following chemotherapy.

METHOD

Mitochondria were isolated from mouse livers, their activity and integrity were validated with MitoTracker Red and their localization was examined via confocal microscopy, real-time quantitative PCR and enzyme-linked immunosorbent assay post tail vein injection. An ovarian insufficiency animal model induced by chemotherapy was developed, and ovarian function was assessed through ovarian diameter, vaginal smear, body weight, sex hormone levels and histological analysis. The impact of mitochondrial transplantation on an ovarian cell model was examined through the assessment of mitochondrial function, apoptosis and levels of reactive oxygen species.

CONCLUSION

Tail vein injection of isolated mitochondria has the potential to enhance ovarian functions in an animal model of POI induced by cyclophosphamide, increase mitochondrial activity in impaired ovarian cells and decrease the rate of apoptosis.

Icariin inhibits cisplatin-induced ovarian toxicity via modulating NF-κB and PTEN/AKT/mTOR/AMPK axis

Cisplatin (CP) is a highly effective broad-spectrum chemotherapeutic agent for several solid tumors. However, its clinical use is associated with ovarian toxicity. Icariin (ICA) is a bioactive flavonoid of Epimedium brevicornum with reported protective activities against inflammation, oxidative stress and ovarian failure. This study aimed to explore the protective effects of ICA against CP-associated ovarian toxicity in rats. Rats were randomized into five groups and treated for 17 days: control, ICA (10 mg/kg/day, for 17 days. p.o.), CP (6 mg/kg, i.p. on days 7 and 14), CP + ICA (CP 6 mg/kg i.p. on days 7 and 14 and ICA 5 mg/kg p.o. daily), and CP + ICA (CP 6 mg/kg i.p. on days 7 and 14 and ICA 10 mg/kg p.o. daily). Our results indicated that ICA effectively improved ovarian reserve as indicated by attenuating CP-induced histolopathological changes and enhancing serum anti-müllerian hormone (AMH). Furthermore, co-administration of ICA with CP showed restoration of the oxidant-anti-oxidant balance in ovarian tissues, evidenced by decreased malondialdehyde (MDA) concentrations and elevated superoxide dismutase (SOD) and catalase (CAT) activities. Also, ICA suppressed ovarian inflammation as evidenced by down-regulation of the expression of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α) and nuclear factor kappa B (NF-κB). ICA inhibited ovarian apoptosis in CP-treated rats by down-regulation of CASP3 and Bax and up-regulation of Bcl-2 mRNA expression. Further, ICA enhanced PTEN, p-AKT, p-mTOR, and p-AMPKα expression. In conclusion, ICA possesses a protective activity against CP-induced ovarian toxicity in rats by exhibiting antioxidant, antiinflammatory, anti-apoptotic activities and modulating NF-κB expression and PTEN/AKT/mTOR/AMPK axis in ovarian tissues.

Ovarian tissue cryopreservation and transplantation as a natural means to delay menopause

Ovarian tissue cryopreservation and transplantation (OTCT) offers hope for preserving fertility and endocrine functions in patients undergoing gonadotoxic treatments. Advancements in techniques for the procedure have transformed OTCT from an experimental procedure into a viable option. There is a growing interest in utilizing OTCT to delay menopause and alleviate associated health issues. Menopausal transition affects women globally, leading to symptoms and long- term health risks. OTCT has the potential to restore endocrine functions, reducing menopause-related symptoms while mitigating health consequences such as osteoporosis and cardiovascular diseases. Although the use of OTCT for delaying menopause is not clinically proven, the discussion around shows potential for future utilization. In essence, the remarkable advancements in OTCT have bestowed upon us the ability to safeguard fertility and sustain the delicate endocrine functions of the ovaries. However, it is the tantalizing prospect of utilizing this technique to postpone menopause and alleviate its associated symptoms that truly captivates the imagination. Further research is imperative to substantiate the clinical efficacy of OTCT; nonetheless, its potential in menopausal therapy is both promising and warrants comprehensive exploration. This review highlights advancements and the feasibility of OTCT to postpone menopause as an alternative approach to currently used conventional menopause therapy methods.

Fertility Preservation in BRCA1/2 Germline Mutation Carriers: An Overview

BRCA1 and BRCA2 mutations are responsible for a higher incidence of breast and ovarian cancer (from 55% up to 70% vs. 12% in the general population). If their functions have been widely investigated in the onset of these malignancies, still little is known about their role in fertility impairment. Cancer patients treated with antineoplastic drugs can be susceptible to their gonadotoxicity and, in women, some of them can induce apoptotic program in premature ovarian follicles, progressive depletion of ovarian reserve and, consequently, cancer treatment-related infertility (CTRI). BRCA variants seem to be associated with early infertility, thus accelerating treatment impairment of ovaries and making women face the concrete possibility of an early pregnancy. In this regard, fertility preservation (FP) procedures should be discussed in oncofertility counseling-from the first line of prevention with risk-reducing salpingo-oophorectomy (RRSO) to the new experimental ovarian stem cells (OSCs) model as a new way to obtain in vitro-differentiated oocytes, several techniques may represent a valid option to BRCA-mutated patients. In this review, we revisit knowledge about BRCA involvement in lower fertility, pregnancy feasibility, and the fertility preservation (FP) options available.

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.

Comparison of liquid nitrogen-free slow freezing protocols toward enabling a practical option for centralized cryobanking of ovarian tissue

Geographically distributed ovarian tissue cryobanks remain limited due to the high facility and staff costs, and cold transportation to centers is associated with ischemia-induced tissue damage that increases with transport distance. It is ideal to perform the cryopreservation procedure at a tissue removal site or local hospital before shipment to cost-effective centralized cryobanks. However, conventional liquid nitrogen-based freezers are not portable and require expensive infrastructure. To study the possibility of an ovarian tissue cryopreservation network not dependent on liquid nitrogen, we cryopreserved bovine ovarian tissue using three cooling techniques: a controlled rate freezer using liquid nitrogen, a liquid nitrogen-free controlled rate freezer, and liquid nitrogen-free passive cooling. Upon thawing, we evaluated a panel of viability metrics in frozen and fresh groups to examine the potency of the portable liquid nitrogen-free controlled and uncontrolled rate freezers in preserving the ovarian tissue compared to the non-portable conventional controlled rate freezer. We found similar outcomes for reactive oxygen species (ROS), total antioxidant capacity (TAC), follicular morphology, tissue viability, and fibrosis in the controlled rate freezer groups. However, passive slow cooling was associated with the lowest tissue viability, follicle morphology, and TAC, and the highest tissue fibrosis and ROS levels compared to all other groups. A stronger correlation was found between follicle morphology, ovarian tissue viability, and fibrosis with the TAC/ROS ratio compared to ROS and TAC alone. The current study undergirds the possibility of centralized cryobanks using a controlled rate liquid nitrogen-free freezer to prevent ischemia-induced damage during ovarian tissue shipment.

Fertility Preservation Knowledge, Attitudes, and Self-Reported Behaviors of Resident Physicians

Purpose: Fertility preservation (FP) and family building are important considerations for quality survivorship for young cancer patients. Resident physicians across all specialties encounter reproductive-aged cancer patients. The purpose of this study was to assess resident physicians' attitudes and awareness about FP with the goal to identify specific educational gaps to direct future training. Methods: The Institutional Review Board (IRB)-approved anonymous online survey was sent to resident physicians across specialties at three separate academic-affiliated campuses in one state. The survey consisted of three sections: awareness about FP options and knowledge about referral placement, attitudes and comfort levels discussing FP, and practices regarding FP. Data were collected in Qualtrics and analyzed by resident specialty, age, level of training, and gender. Statistical analyses were conducted with Prism. Results: Obstetrics and gynecology residents and fellows were significantly more aware of FP options in cancer patients than their counterparts in other specialties. Postgraduate year (PGY 3) residents and beyond were more aware of at least one male and one female FP option compared with PGY 1 and 2 residents. Of importance, we found that the majority of resident physicians are aware of FP options and the referral process, but they are uncomfortable discussing these techniques with their patients. Conclusion: To provide better education for patients, focus should be on outpatient educational activities for both the health care provider and the patient to facilitate conversation about FP.

The Impact of Systemic Oncological Treatments on the Fertility of Adolescents and Young Adults-A Systematic Review

BACKGROUND

Over the past decades, advancements in oncological treatments have led to major improvements in survival. Particularly for adolescents and young adults (AYAs), fertility is an important concern in cancer survivorship. The purpose of the review is to provide physicians with a practical overview of the current knowledge about the impact of systemic oncological treatments on the fertility of female and male AYAs.

METHODS

A systematic review was performed based on relevant articles obtained from 4 databases up until 31 December 2022.

RESULTS

The mechanisms of gonadotoxicity and the concurrent risk is described for the following categories: chemotherapy, targeted therapy and immunotherapy. For the category "chemotherapy", the specific effects and risks are listed for the different classes and individual chemotherapeutics. In the category "targeted therapy", a distinction was made between tyrosine kinase inhibitors (TKIs) and monoclonal antibodies. Information concerning immunotherapy is scarce.

CONCLUSIONS

The effects of chemotherapy on fertility are well investigated, but even in this category, results can be conflicting. Insufficient data are available on the fertility effects of targeted therapy and immunotherapy to draw definitive conclusions. More research is needed for these therapies and their evolving role in treating cancers in AYAs. It would be useful to include fertility endpoints in clinical trials that evaluate new and existing oncological treatments.

Fertility discussions and concerns in childhood cancer survivors, a systematic review for updated practice

PURPOSE

To provide ways to improve the clinical practice of fertility preservation (FP) for children, adolescents, and young adults (AYA) with cancer.

DESIGN

A systematic research of online databases was undertaken in March 2020 following the PRISMA criteria, including Medline and Web of Science.

RESULTS

Fifty-nine articles were included. Surveys, interviews, and focus groups were used to collect data from patients, parents, and health care providers (HCPs). Four themes worth exploring emerged: (a) what do patients and professionals think of and know about FP? (b) what makes the fertility discussion happen or not? (c) what, retrospectively, led to FP being pursued or not? and (d) how do patients and HCPs feel about fertility issues?

CONCLUSION

A minority of AYAs preserve their fertility (banking assay for 45% of boys and 23% of girls). Yet fertility concerns have a significant impact on the quality of life of young cancer survivors. Although recommendations and guidelines regarding FP are available internationally, there are no specific guidelines as to how to conduct fertility counseling for children and adolescents. Some barriers are not removable, such as a poor prognosis of an obvious severe disease, time constraints for starting treatment, and cultural and religious beliefs. In response to aspects hindering patients and families to be receptive to any discussion at the time of diagnosis, psychological support could reduce the level of emotional distress and help restore a degree of open-mindedness to open a window for discussion. Moreover, as the lack of knowledge of professionals about fertility is frequently pointed out as a limiting factor for fertility discussion, reinforcing professional training regarding FP could be proposed to promote fertility discussion and eventually referral for FP.

Signaling pathway intervention in premature ovarian failure

Premature ovarian failure (POF) is a multifactorial disease that refers to the occurrence of secondary amenorrhea, estrogen decrease, and gonadotropin increase in women under the age of 40. The prevalence of POF is increasing year by year, and the existing instances can be categorized as primary or secondary cases. This disease has adverse effects on both the physiology and psychology of women. Hormone replacement therapy is the recommended treatment for POF, and a multidisciplinary strategy is required to enhance the quality of life of patients. According to recent studies, the primary mechanism of POF is the depletion of ovarian reserve function as a result of increased primordial follicular activation or primordial follicular insufficiency. Therefore, understanding the processes of primordial follicle activation and associated pathways and exploring effective interventions are important for the treatment of POF.

Germline stem cells in human

The germline cells are essential for the propagation of human beings, thus essential for the survival of mankind. The germline stem cells, as a unique cell type, generate various states of germ stem cells and then differentiate into specialized cells, spermatozoa and ova, for producing offspring, while self-renew to generate more stem cells. Abnormal development of germline stem cells often causes severe diseases in humans, including infertility and cancer. Primordial germ cells (PGCs) first emerge during early embryonic development, migrate into the gentile ridge, and then join in the formation of gonads. In males, they differentiate into spermatogonial stem cells, which give rise to spermatozoa via meiosis from the onset of puberty, while in females, the female germline stem cells (FGSCs) retain stemness in the ovary and initiate meiosis to generate oocytes. Primordial germ cell-like cells (PGCLCs) can be induced in vitro from embryonic stem cells or induced pluripotent stem cells. In this review, we focus on current advances in these embryonic and adult germline stem cells, and the induced PGCLCs in humans, provide an overview of molecular mechanisms underlying the development and differentiation of the germline stem cells and outline their physiological functions, pathological implications, and clinical applications.