Advances in anti-neoplastic therapy have led to a significant increase in survival rates in recent decades, especially in the field of pediatric cancer. The goal at this moment is to offer complete and safe recovery, with acceptable quality of life and full reintegration into society. From an endocrine-gonadal standpoint, we know that some treatments used in childhood cancer can cause premature ovarian failure. Reproductive capacity in humans is not considered a trivial value and is clearly related to feelings of well-being and personal autonomy. Parallelly, in recent years, assisted reproduction techniques have made true progress, and nowadays, designing alternatives to preserve fertility in cancer-diagnosed patients has become a priority for many professionals. Ovarian tissue cryopreservation (OTC) currently is the only viable option for prepubertal patients, but it is important to emphasize its still experimental nature, and there are not many studies aimed at its optimization.

The overall objective of this project is to improve current strategies for fertility preservation in prepubertal girls with cancer. The project will focus on improving the current freezing system used in Spanish hospitals that offer this service, by creating an automated microfluidic system for tissue freezing. The project has been named HOTCOnChip (Human Ovarian Tissue Cryopreservation On Chip). In this initial phase of the project, samples of adult human ovarian tissue will be used to find the best freezing conditions to maintain follicular and ovarian stroma integrity and functionality. This project has the approval of CEICA to use human adult ovarian tissue. In subsequent phases, results will be extrapolated to ovarian tissue from girls once positive results are obtained in adult tissue and CEICA approval is obtained to use the prepubertal material, which is so valuable. This project is multidisciplinary and innovative, focusing on advanced bioengineering solutions to preserve fertility. This knowledge will be crucial for oncofertility in girls, increasing future possibilities of establishing pregnancies in pediatric oncology patients. The beneficiary organization of the HOTCOnChip project will be the Aragon Health Research Institute (IIS Aragon), more specifically the Tissue Microenvironment lab (TME; https://tmelab.unizar.es/).