Development of Human Pituitary Adenoma Organoids to Facilitate Effective Targeted Treatments of Cushing's Disease.

Abstract Cushing's disease (CD) is a serious endocrine disorder caused by dysregulated adrenocorticotropic hormone (ACTH)-secreting pituitary tumor that stimulates the adrenal glands to overproduce cortisol. Chronic exposure to excess cortisol has detrimental effects on health, including increased stroke rates, diabetes, obesity, cognitive impairment, anxiety, depression, and death. The first-line treatment for CD is pituitary surgery, which is followed by disease remission. Current surgical remission rates reported range from 47–85% depending on several remission criteria. The lack of specificity, poor tolerability, and low efficacy of the subsequent second-line medical therapies makes CD a medical therapeutic challenge. One major limitation that hinders the development of specific medical therapies is the lack of human relevant model systems that recapitulate the cellular composition of pituitary adenomas. Human pituitary adenoma tissue was harvested during transsphenoidal surgery from CD patients to generate organoids (hPITOs). hPITOs generated from corticotroph, lactotroph, gonadotroph and somatotroph adenomas exhibited morphological diversity among the organoid lines between individual patients and amongst subtypes. The similarity in cell lineages between the organoid line and the patient’s tumor was validated by comparing the neuropathology report to the expression pattern of pituitary adenoma specific markers using spectral flow cytometry and exome sequencing. A high-throughput drug screen demonstrated patient-specific drug responses of hPITOs amongst each adenoma subtype. Generation of induced pluripotent stem cells (iPSCs) from patients carrying germline mutations relevant to CD exhibited dysregulated cell lineage commitment. The human pituitary adenoma organoids represent a novel approach in how we model complex pathologies in CD patients that may enable more effective personalized medicine for these patients.