An hIPS cells-derived adrenocortical organoid system for disease modeling and drug screening – AdOrga

The adrenal cortex is a vital endocrine organ that controls a wide range of biological parameters including metabolism, blood pressure and immune response, through the release of distinct steroid hormones. As adrenal diseases can be life-threatening, understanding their molecular underpinnings and developing novel therapeutic approaches are important goals. Current research models for human adrenocortical biology are sparse and limited to a few patient-derived cell lines. Generation of adrenocortical cells and organoids from human induced pluripotent stem cells (hIPSC) would provide a novel experimental system to model human normal and pathological processes in vitro, and could provide proof of principle for the development of drug screening and cell replacement therapy approaches. As strategies for directed-stem cell differentiation often recapitulate developmental processes, understanding how adrenocortical cells are specified in vivo is of great importance. Aim of this project is to better characterize early adrenocortical ontogenesis, exploit this knowledge to establish an hIPSC-derived adrenocortical organoid system, and evaluate its use as a model to study human adrenocortical biology and cancer.
We will delineate the mesodermal origin of early adrenocortical progenitors, for both mouse and human with a dual in vivo/in vitro approach. We will leverage known and novel findings to establish robust conditions for hIPSC-derived adrenocortical organoids generation, by evaluating known and novel regulators of specification, differentiation, zonal conversion and hormone production. hIPSC-derived cells/spheroids will be monitored for their functionality, physiological responsiveness, 3D spatial organization and similarities with human adrenal glands. Transplantation in mice will assess their long-term maintenance and response to the HPA and RAAS axis in vivo. We will exploit this system to develop a panel of in vitro adrenocortical cancer models by introducing mutations found in patients, and score their pathological features. Drug responses will be assessed following treatment with mitotane and/or anti-proliferative drugs, as well as novel regulators of adrenocortical progenitors recruitment, differentiation and proliferation.
Altogether, this project will yield a streamlined protocol for hIPSC-derived adrenocortical organoids and generate a panel of in vitro human adrenocortical cancer models that can be used for studying cancer and drug development.