Strategies to safely use cryopreserved ovarian tissue to restore fertility after cancer: a systematic review.

Ovarian tissue cryopreservation and subsequent autotransplantation is a successful technique for fertility preservation in oncological patients. However, there are concerns regarding safety, as the graft may contain malignant cells that could lead to the reintroduction of cancer. To circumvent this problem several experimental strategies are being pursued.

Assessing the use of tumor-specific DARPin-toxin fusion proteins for ex vivo purging of cancer metastases from human ovarian cortex before autotransplantation.

Objective: To assess the use of tumor-specific designed ankyrin repeat proteins (DARPins) fused to a domain of Pseudomonas aeruginosa exotoxin A for purging of cancer metastases from the ovarian cortex.

Design: Experimental study.

Setting: University medical center.

Complete Purging of Ewing Sarcoma Metastases from Human Ovarian Cortex Tissue Fragments by Inhibiting the mTORC1 Signaling Pathway.

Restoration of fertility by autologous transplantation of ovarian cortex tissue in former cancer patients may lead to the reintroduction of malignancy via the graft. Pharmacological ex vivo purging of ovarian cortex fragments prior to autotransplantation may reduce the risk of reseeding the cancer. In this study we have investigated the capacity of Everolimus (EVE), an inhibitor of the mammalian target of rapamycin complex 1 (mTORC1) signaling pathway, to eradicate Ewing's sarcoma (ES) from ovarian tissue by a short-term ex vivo treatment.

Purging human ovarian cortex of contaminating leukaemic cells by targeting the mitotic catastrophe signalling pathway.

Purpose: Is it possible to eliminate metastasised chronic myeloid leukaemia (CML) and acute myeloid leukaemia (AML) cells from ovarian cortex fragments by inhibition of Aurora B/C kinases (AURKB/C) without compromising ovarian tissue or follicles?

Methods: Human ovarian cortex tissue with experimentally induced tumour foci of CML, AML and primary cells of AML patients were exposed to a 24h treatment with 1 μM GSK1070916, an AURKB/C inhibitor, to eliminate malignant cells by invoking mitotic catastrophe. After treatment, the inhibitor was removed, followed by an additional culture period of 6 days to allow any remaining tumour cells to form new foci. Ovarian tissue integrity after treatment was analysed by four different assays.

Enhancing the safety of ovarian cortex autotransplantation: cancer cells are purged completely from human ovarian tissue fragments by pharmacological inhibition of YAP/TAZ oncoproteins.

Study Question: Is it possible to eliminate metastasized cancer cells from ovarian cortex fragments prior to autotransplantation without compromising the ovarian tissue or follicles?

Summary Answer: Ex vivo pharmacological inhibition of YAP/TAZ by Verteporfin enabled us to efficiently eradicate experimentally induced small tumours, derived from leukaemia and rhabdomyosarcoma, from human ovarian tissue fragments.

What Is Known Already: Autotransplantation of ovarian tissue fragments that contain metastasized tumour cells may reintroduce the malignancy to the recipient. In order to enhance safety for the patient there is a strong need for protocols that effectively purges the ovarian tissue from malignant cells ex vivo prior to transplantation, without compromising ovarian tissue integrity.