Pediatric Oncofertility: From Cryopreservation to Future Fertility Solutions

Globalcast MD along with Ann and Robert H. Lurry Children's Hospital of Chicago at the forefront of a healthier future for every child. In today's video from Ann and Robert H. Lurry Children's Hospital of Chicago, we hear from Doctor Monica Laronda on pediatric oncofertility. A clinical program supported by Near, Next, and Future innovation. Doctor Lahonda is the Giswaldo Foundation Research scholar at the Stanley Manny Children's Research Institute at the Anne and Robert H. Lurry Children's Hospital of Chicago. She works in close partnership with Doctor Erin Rowell, medical director of the Fertility and Hormone Preservation and Restoration Program here at Luie Children's, who has also been a key player in bringing the program to life. Before we dive into the exciting innovations within the field of pediatric oncofertility, let's first review why and for whom fertility proof preservation is performed. Cancer treatments, while life preserving, can have off-target effects. This includes gonadal failure, which in this case refers to a lack of or decrease in the function of the reproductive organs due to cancer therapies, thus limiting or destroying the patient's ability to produce offspring in the future. There is a significant desire for better quality of life parameters and childhood cancer survivors. And one of the top quality of life parameters that are of importance is the loss of control over reproductive future. And most cancer survivors prefer to have a biological offspring over a gamete donation or a gestational carrier. In order to support these desires for improved quality of life for cancer survivors, the American Society of Clinical Oncology teamed up with other oncologic societies and came up with new recommendations and guidelines. These guidelines underscore the importance of discussing with newly diagnosed cancer patients that their future fertility may be affected by cancer treatments. We know from our own research that parents want fertility preservation options presented for their children. Regardless of their infertility risk or prognosis. But preserving fertility isn't just for cancer patients. It is important to include any child at risk for premature gonadal insufficiency, which includes Turner syndrome and mixed gonadal dysgenesis. So what can we offer our patients at Laurie Children's? At Laurie Children's, we have a fertility and hormone preservation and restoration program that counsels and educates parents and children who are undergoing treatments or have a genetic diagnosis that would affect their future fertility. Children with ovaries can undergo ovarian stimulation and oocyte retrieval and egg banking if they've gone through puberty and are producing eggs, or ovarian tissue cryopreservation is available for pediatric, adolescent and young adult patients. Children with testes can bank sperm if they've gone through puberty or opt for testicular tissue cryopreservation. Laurie Children's collaborates with the University of Pittsburgh Medical Center as they specialize in testicular tissue cryopreservation. But how do we determine a patient's risk for premature gonadal insufficiency? We determine whether or not a patient is at minimal, significant. or high increased risk of developing premature gonadal insufficiency by calculating their cumulative cyclophosphamide equivalent dose, imminent surgery, chemotherapy with alkalating agents, or radiation therapy. Implicates future fertility and reproductive hormone potential. For example, a normal ovary has about 300,000 follicles or potential eggs at the time of birth. This number declines steadily as the patient ages until reaching menopause around age 50. However, an ovary that is exposed to one of the previously discussed therapies will have a dramatic reduction in egg cells, which results in early menopause. In this example, I'm showing that a 12-year-old that receives radiation of 10 gray can undergo menopause at approximately 19.5 years old. Not only is this child or young adult experiencing menopause and infertility, but their life expectancy can be reduced by 2 years from additional comorbidities that result from the lack of gonadal hormones that are no longer produced by those ovaries. Because of the clear need for ongoing research regarding fertility preservation, the Onco Fertility Consortium was created. This consortium addresses the complex health issues and quality of life issues that concern young cancer patients whose fertility may be threatened by their disease or treatment. It represents a nationwide interdisciplinary and interprofessional network of medical specialists, scientists, and scholars. Today, this reaches beyond cancer, and the legacy lives in scientific innovations, advocacy and education, and has since expanded to be a worldwide consortium. Our fertility and hormone preservation and restoration program at Larry Children's first started collaborating with the Northwestern University, Oncofertility Consortium in 2011. Their first patient was enrolled in March of 2011 and underwent ovarian tissue cryopreservation. In 2015, they opened the program for testicular tissue cryopreservation, and in 2016, the fertility and hormone Preservation and Restoration Program was selected as a research accelerator initiative. Their team continued to expand and now includes a research coordinator, surgical research fellows, FHPR technicians, and advanced practice providers. They also have their own gonadal tissue processing suite at Laurie Children's. We have now had over 200 ovarian tissue cryopreservation patients and approximately 170 testicular tissue cryopreservation patients. We perform ovarian tissue cryopreservation for patients across the country, and approximately 25% of our ovarian tissue cryopreservation patients. are referrals from outside of Laurie Children's Hospital. We have demonstrated that the safety and efficacy of the process is strong, and more individuals are aware that this fertility preservation option is available to them. Now that we know about the program, let's walk through the algorithm for a patient ovarian tissue cryopreservation is performed with a unilateral oophorectomy by our pediatric surgeons. The other ovary compensates and maintains the same level of hormones. The remaining ovary can release more eggs when stimulated for assisted reproductive technologies, and there is little difference in age at menopause. When able, the laparoscopic oophorectomy is done at the time of another procedure that is required for the patient's cancer diagnosis, such as a port placement. This decreases the number of times the patient will be under general anesthesia. Our patients are generous in that they donate blood, biospeciens, clinical data, and outcomes for our research and to advance the program for themselves and for future ovarian tissue cryopreservation or OTC patients. This generosity allowed the research team to determine depth of primordial follicles within the ovaries of pediatric patients. We process the ovarian tissue in order to cryopreserve the primordial follicles. Which will be saved for future use for the patient. Once the ovary has made it to the gonadal tissue preservation suite, the tissue is processed. The ovary is butterflied, thinned, and prepared for cytoprotectant, then divided into strips, which are then moved into the individual cryovials where they are stored for years or decades. Now that we know a bit more about ovarian tissue preservation, let's learn more about the next step, ovarian tissue transplantation or OTT. It's been nearly 30 years since the first studies were done. The first successful ovarian tissue cryopreservation and transplantation in a large animal model was done in sheep in 1994. The first orthotopic human transplant was performed in the pelvic wall in 2000. The first heterotopic human transplant was performed in the arm, and it wasn't until 2001 that the first embryos were developed through heterotopic transplant. And the first live births following an ovarian autotransplant from a frozen thawed tissue happened between 2004 and 2006 in Israel. Right now, the current state of the field is that autotransplantation of ovarian tissue can restore function. There's approximately 140 reported live births. The rate of autotransplantation for recipients who have restored fertility is between 20% and 40%. Hormone production lasts an average of 2 to 5 years and has been reported to exceed 12 years. However, for many of our cancer patients, there is a possibility of reintroducing cancer cells from their tissue. And this just describes the need for improving this research. As Doctor Lahonda stated, many patients cannot undergo autotransplantation due to the risk of reintroducing cancer cells into the bodies. Because of this risk, recent studies have focused on in vitro follicle growth and maturation, or to develop a bioprosthetic ovary. The idea is that the primordial follicles, which are the desired cells, are removed from any cancer cells. The follicles are then placed into a supportive engineered microenvironment that produces continuous hormones and regular ovulation in order to have spontaneous pregnancies. The clinical purpose, of course, is to fulfill the gaps that exist with fertility restoration for our patients, improve the current rates of live births, and increase the longevity of hormone production after autotransplantation. They developed a 3D printed scaffold composed of 10% gelatin and were able to grow healthy oocytes from mice. Green fluorescent protein expressing follicles were added to the 3D printed scaffold and transplanted into a mouse without this green protein. And they were able to spontaneously produce pups that expressed the green fluorescent protein. And so we therefore know that these eggs that were ovulated from the bioprosthetic ovary were produced from this transplant, and not from the native mouse ovaries. But how do we translate this to human models? Laurie Children's has received a HubMap consortium grant and is now a contributing site. They will generate a normal human ovary atlas where they will describe the ovary microenvironment across development. We've already identified that infants with very young ovaries are significantly different in their makeup of the different cell types that are present in comparison to prepubertal and postpubertal ovaries from slightly older individuals. With this information, We'll be able to reverse engineer a neighborhood to understand and inform ovarian function. So, the next step is to create tools to distinguish between follicular responses to physical and biochemical cues. We wanted to understand exactly what and where specific types of extracellular matrix and associated proteins collectively called the matrosome existed within the ovary. We found that there were 82 different matrosome proteins and 42 that were significantly differentially expressed across these different compartments. We even discovered 11 matrosome proteins that had not yet been previously identified within the ovary. They were able to identify that certain proteins were more abundant in specific regions of the ovary. Through this research, they then identified specific proteins that may influence follicular genesis, such as the EMILIN1 protein. We also know that the physical properties of the ovarian compartments can influence follicular genesis. The Laonda lab sought to determine if the rigidity of the ovary is dependent on the extracellular matrix, ECM proteins, by measuring the density of the ECM at each slice. They found that the density of the ECM protein matched the rigidity curve of the atomic force microscopy analysis. The rigidity of the ovary might be in part due to the amount of extracellular matrix proteins that exist within a region. This is important information to understand when we're developing the next generation of a bioprosthetic ovary. With this new information, they can use biomaterials to investigate proteins of interest and to better understand how follicles react in various environments. In summary, much research is still required for pediatric and adolescent OTC and OTT. Ovarian tissue engineering aims to expand our understanding of follicuogenesis and improve restoration options. 3D printed bioprosthetic scaffolds restore fertility and hormone function in mice. Ongoing research will decipher which properties are critical to support folliculogenesis and maintain longevity of OTT. Globalcast MD along with Ann and Robert H. Laurie Children's Hospital of Chicago, at the forefront of a healthier future for every child.