Role of Stress-Responsive NR4A2 in Aldosterone-Producing Cell Cluster Formation

BACKGROUND: Aldosterone-producing cell clusters (APCCs), which share some transcriptomic features with aldosterone-producing adenomas, are frequently observed in the adrenal cortex of aged individuals and those with primary aldosteronism. However, the mechanisms driving APCC formation remain poorly understood. METHODS: We performed an integrated analysis using spatial transcriptomics and single-cell RNA sequencing of APCC cells, aldosterone-producing adenoma cells, and zona glomerulosa (ZG) cells present in the same adrenal gland of a patient with unilateral primary aldosteronism, with validation analyses conducted on tissue samples from 2 additional patients. RESULTS: APCC cells exhibited a distinct cellular population with a gene expression profile more similar to that of the ZG cells than that of aldosterone-producing adenoma cells. In silico perturbation and in vitro studies suggest that the stress-responsive TF (transcription factor) NR4A2 is activated in ZG cells in response to a variety of stresses, such as ACTH (adrenocorticotropic hormone) stimulation, thereby promoting the progression from ZG to APCC cells. CONCLUSIONS: Our findings suggest that NR4A2 activation in ZG cells functions as a key molecular mediator in stress-induced APCC formation at least in some cases. Some APCCs maintained ZG-like characteristics with heightened stress responsiveness, representing a distinct cellular state from aldosterone-producing adenomas, which exhibit metabolic reprogramming and enhanced energy metabolism.