Primary Aldosteronism: Spatial Multiomics Mapping of Genotype-Dependent Heterogeneity and Tumor Expansion of Aldosterone-Producing Adenomas

Primary aldosteronism is frequently caused by an adrenocortical aldosterone-producing adenoma (APA) carrying a somatic mutation that drives aldosterone overproduction. APAs with a mutation in (APA- ) are characterized by heterogeneous CYP11B2 (aldosterone synthase) expression, a particular cellular composition and larger tumor diameter than those with wild-type (APA- ). We exploited these differences to decipher the roles of transcriptome and metabolome reprogramming in tumor pathogenesis. Consecutive adrenal cryosections (7 APAs and 7 paired adjacent adrenal cortex) were analyzed by spatial transcriptomics (10x Genomics platform) and metabolomics (in situ matrix-assisted laser desorption/ionization mass spectrometry imaging) co-integrated with CYP11B2 immunohistochemistry. We identified intratumoral transcriptional heterogeneity that delineated functionally distinct biological pathways. Common transcriptomic signatures were established across all APA specimens which encompassed 2 distinct transcriptional profiles in CYP11B2-immunopositive regions ( -type 1 or 2). The -type 1 signature was characterized by zona glomerulosa gene markers and was detected in both APA- and APA- . The -type 2 signature displayed markers of the zona fasciculata or reticularis and predominated in APA- . Metabolites that promote oxidative stress and cell death accumulated in APA- . In contrast, antioxidant metabolites were abundant in APA- . Finally, APA-like cell subpopulations-negative for CYP11B2 gene expression-were identified in adrenocortical tissue adjacent to APAs suggesting the existence of tumor precursor states. Our findings provide insight into intra- and intertumoral transcriptional heterogeneity and support a role for prooxidant versus antioxidant systems in APA pathogenesis highlighting genotype-dependent capacities for tumor expansion.