Expression of steroidogenic enzymes and their transcription factors in cortisol-producing adrenocortical adenomas: immunohistochemical analysis and quantitative real-time polymerase chain reaction studies

Molecular classification and tumor microenvironment characteristics in pheochromocytomas

Pheochromocytomas (PCCs) are rare neuroendocrine tumors that originate from chromaffin cells in the adrenal gland. However, the cellular molecular characteristics and immune microenvironment of PCCs are incompletely understood. Here, we performed single-cell RNA sequencing (scRNA-seq) on 16 tissues from 4 sporadic unclassified PCC patients and 1 hereditary PCC patient with Von Hippel-Lindau (VHL) syndrome. We found that intra-tumoral heterogeneity was less extensive than the inter-individual heterogeneity of PCCs. Further, the unclassified PCC patients were divided into two types, metabolism-type (marked by NDUFA4L2 and COX4I2) and kinase-type (marked by RET and PNMT), validated by immunohistochemical staining. Trajectory analysis of tumor evolution revealed that metabolism-type PCC cells display phenotype of consistently active metabolism and increased metastasis potential, while kinase-type PCC cells showed decreased epinephrine synthesis and neuron-like phenotypes. Cell-cell communication analysis showed activation of the annexin pathway and a strong inflammation reaction in metabolism-type PCCs and activation of FGF signaling in the kinase-type PCC. Although multispectral immunofluorescence staining showed a lack of CD8+ T cell infiltration in both metabolism-type and kinase-type PCCs, only the kinase-type PCC exhibited downregulation of HLA-I molecules that possibly regulated by RET, suggesting the potential of combined therapy with kinase inhibitors and immunotherapy for kinase-type PCCs; in contrast, the application of immunotherapy to metabolism-type PCCs (with antigen presentation ability) is likely unsuitable. Our study presents a single-cell transcriptomics-based molecular classification and microenvironment characterization of PCCs, providing clues for potential therapeutic strategies to treat PCCs.

Molecular and Epigenetic Control of Aldosterone Synthase, CYP11B2 and 11-Hydroxylase, CYP11B1

Aldosterone and cortisol serve important roles in the pathogenesis of cardiovascular diseases and metabolic disorders. Epigenetics is a mechanism to control enzyme expression by genes without changing the gene sequence. Steroid hormone synthase gene expression is regulated by transcription factors specific to each gene, and methylation has been reported to be involved in steroid hormone production and disease. Angiotensin II or potassium regulates the aldosterone synthase gene, CYP11B2. The adrenocorticotropic hormone controls the 11b-hydroxylase, CYP11B1. DNA methylation negatively controls the CYP11B2 and CYP11B1 expression and dynamically changes the expression responsive to continuous stimulation of the promoter gene. Hypomethylation status of the CYP11B2 promoter region is seen in aldosterone-producing adenomas. Methylation of recognition sites of transcription factors, including cyclic AMP responsive element binding protein 1 or nerve growth factor-induced clone B, diminish their DNA-binding activity. A methyl-CpG-binding protein 2 cooperates directly with the methylated CpG dinucleotides of CYP11B2. A low-salt diet, treatment with angiotensin II, and potassium increase the CYP11B2 mRNA levels and induce DNA hypomethylation in the adrenal gland. A close association between a low DNA methylation ratio and an increased CYP11B1 expression is seen in Cushing's adenoma and aldosterone-producing adenoma with autonomous cortisol secretion. Epigenetic control of CYP11B2 or CYP11B1 plays an important role in autonomic aldosterone or cortisol synthesis.

Impact of Morphology in the Genotype and Phenotype Correlation of Bilateral Macronodular Adrenocortical Disease (BMAD): A Series of Clinicopathologically Well-Characterized 35 Cases

Bilateral macronodular adrenocortical disease (BMAD) is characterized by the development of adrenal macronodules resulting in a pituitary-ACTH independent Cushing's syndrome. Although there are important similarities observed between the rare microscopic descriptions of this disease, the small series published are not representative of the molecular and genetic heterogenicity recently described in BMAD. We analyzed the pathological features in a series of BMAD and determined if there is correlation between these criteria and the characteristics of the patients. Two pathologists reviewed the slides of 35 patients who underwent surgery for suspicion of BMAD in our center between 1998 and 2021. An unsupervised multiple factor analysis based on microscopic characteristics divided the cases into 4 subtypes according to the architecture of the macronodules (containing or not round fibrous septa) and the proportion of the different cell types: clear, eosinophilic compact, and oncocytic cells. The correlation study with genetic revealed subtype 1 and subtype 2 are associated with the presence of ARMC5 and KDM1A pathogenic variants, respectively. By immunohistochemistry, all cell types expressed CYP11B1 and HSD3B1. HSD3B2 staining was predominantly expressed by clear cells whereas CYP17A1 staining was predominant on compact eosinophilic cells. This partial expression of steroidogenic enzymes may explain the low efficiency of cortisol production in BMAD. In subtype 1, trabeculae of eosinophilic cylindrical cells expressed DAB2 but not CYP11B2. In subtype 2, KDM1A expression was weaker in nodule cells than in normal adrenal cells; alpha inhibin expression was strong in compact cells. This first microscopic description of a series of 35 BMAD reveals the existence of 4 histopathological subtypes, 2 of which are strongly correlated with the presence of known germline genetic alterations. This classification emphasizes that BMAD has heterogeneous pathological characteristics that correlate with some genetic alterations identified in patients.

Investigation of combined effects of propyl paraben and methyl paraben on the hypothalamic-pituitary-adrenal axis in male rats

The aim of this study was to investigate the endocrine-disrupting effects of methyl paraben (MeP) and propyl paraben (PrP) mixture on the hypothalamic-pituitary-adrenal axis (HPA). In this study, six experimental groups were designated. These groups included three control groups (control, corn oil control, and positive control (50 mg/kg/day BPA)) and three dose groups (10, 100, and 500 mg/kg/day MeP+PrP). MeP with PrP were mixed in a 1:1 ratio and administered to the 42-day-old male rats by oral gavage for 30 days. At the end of the experiment, adrenocorticotropic hormone (ACTH), corticosterone and aldosterone hormones were analyzed in serum. Effects of MeP+PrP on the adrenal glands were investigated by immunohistochemical staining of 11ß hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) enzymes involved in the synthesis steps of corticosterone and aldosterone. Also, pituitary and adrenal glands were examined histopathologically. In the histopathological findings, cortical nodule, congestion, and edema were found in the tissues. In the pituitary gland, cytokeratin rings were detected in all MeP+PrP dose groups, supporting the increase of corticosterone and ACTH. Serum corticosterone, aldosterone, and ACTH hormone levels were increased in the 100 mg/kg/day MeP+PrP and BPA groups. Results obtained from immunohistochemical staining showed that increased staining parallelled increased corticosterone and aldosterone hormone levels. In summary, the results showed that exposure to the MeP+PrP mixture caused a significant increase in ACTH and corticosterone. Also, the MeP+PrP mixture caused a significant increase of CYP11B1 and CYP11B2. MeP+PrP exposure disrupts the normal HPA axis.

Association of DNA methylation with steroidogenic enzymes in Cushing's adenoma

DNA methylation and demethylation regulate the transcription of genes. DNA methylation-associated gene expression of adrenal steroidogenic enzymes may regulate cortisol production in cortisol-producing adenoma (CPA). We aimed to determine the DNA methylation levels of all genes encoding steroidogenic enzymes involved in CPA. Additionally, the aims were to clarify the DNA methylation-associated gene expression and evaluate the difference of CPA genotype from others using DNA methylation data. Twenty-five adrenal CPA and six nonfunctioning adrenocortical adenoma (NFA) samples were analyzed. RNA sequencing and DNA methylation array were performed. The methylation levels at 118 methylation sites of the genes were investigated, and their methylation and mRNA levels were subsequently integrated. Among all the steroidogenic enzyme genes studied, CYP17A1 gene was mainly found to be hypomethylated in CPA compared to that in NFA, and the Benjamini-Hochberg procedure demonstrated that methylation levels at two sites in the CYP17A1 gene body were statistically significant. PRKACA mutant CPAs predominantly exhibited hypomethylation of CYP17A1 gene compared with the GNAS mutant CPAs. Inverse associations between CYP17A1 methylation in three regions of the gene body and its mRNA levels were observed in the NFAs and CPAs. In applying clustering analysis using CYP17A1 methylation and mRNA levels, CPAs with PRKACA mutation were differentiated from NFAs and CPAs with a GNAS mutation. We demonstrated that CPAs exhibited hypomethylation of the CYP17A1 gene body in CPA, especially in the PRKACA mutant CPAs. Methylation of CYP17A1 gene may influence its transcription levels.

Genotype-specific cortisol production associated with Cushing's syndrome adenoma with PRKACA mutations

The intracellular molecular mechanisms underlying the genotype of cortisol-producing adenoma (CPA) have not been fully determined. We analyzed gene expressions in CPA and the human adrenocortical cell line (HAC15 cells) with PRKACA mutation. Clustering analysis using a gene set associated with responses to cAMP revealed the possible differences between PRKACA mutant CPAs and GNAS and CTNNB1 mutant CPAs. The levels of STAR, CYP11A1, CYP17A1, CYP21A2, and FDX1 transcripts and cortisol levels per unit area in PRKACA mutant CPAs were significantly higher than those in GNAS mutant CPAs. PRKACA mutations led to an increase in steroidogenic enzyme expression and cortisol production in HAC15 cells. Transcriptome analysis revealed differences between PRKACA mutant CPAs and GNAS and CTNNB1 mutant CPAs. Cortisol production in PRKACA mutant CPAs is increased by the cAMP-PKA signaling pathway-mediated upregulation of steroidogenic enzymes transcription. The intracellular molecular mechanisms underlying these processes would be notably important in PRKACA mutant CPAs.

Expression of Key Androgen-Activating Enzymes in Ovarian Steroid Cell Tumor, Not Otherwise Specified

To characterize the expression of steroidogenic enzymes implicated in the development of ovarian steroid cell tumors, not otherwise specified (SCT-NOS). We present 4 ovarian SCT-NOS evaluated by immunohistochemical staining of steroidogenic enzymes as an approach to define this entity pathologically. All 4 ovarian SCT-NOS showed increased expression for cholesterol side-chain cleavage enzyme (CYP11A1), 17α-hydroxylase (CYP17A1), 17β-hydroxysteroid dehydrogenase 1 (HSD17B1), aldo-ketoreductase type 1 C3 (AKR1C3), 3β-hydroxysteroid dehydrogenase 2 (HSD3B2), 5α-reductase type 2 (SRD5A2), steroid sulfatase (SULT2A1), estrogen sulfotransferase (EST), and aromatase (CYP19A1). Expression was negative for 21-hydroxylase (CYP21A2) and 17β-hydroxysteroid dehydrogenase 2 (HSD17B2). 17β-hydroxysteroid dehydrogenase 3 (HSD17B3) and 5α-reductase type 1 (SRD5A1) showed variable expression. Our analysis reveals a novel finding of increased expression of AKR1C3, HSD17B1, SRD5A2, SULT2A1, and EST in ovarian SCT-NOS, which is clinically associated with androgen excess and virilization. Further studies are needed to validate these enzymes as new markers in the evaluation of hyperandrogenic ovarian conditions.

18-Oxocortisol Synthesis in Aldosterone-Producing Adrenocortical Adenoma and Significance of KCNJ5 Mutation Status

Peripheral 18-oxocortisol (18oxoF) level could contribute to the detection of aldosterone-producing adenoma (APA) in patients with primary aldosteronism. However, peripheral 18oxoF varies among such patients, which is a big drawback concerning its clinical application. We studied 48 cases of APA, 35 harboring KCNJ5 mutation, to clarify the significance of clinical and pathological parameters about peripheral 18oxoF. Peripheral 18oxoF concentration ranged widely from 0.50 to 183.13 ng/dL and correlated positively with intratumoral areas stained positively for steroidogenic enzymes ( P<0.0001). The peripheral 18oxoF level also correlated significantly with that of circulating aldosterone ( P<0.0001) but not with that of cortisol, a precursor of 18oxoF. However, a significant correlation was detected between peripheral 18oxoF and intratumoral glucocorticoids ( P<0.05). In addition, peripheral 18oxoF correlated positively with the number of hybrid cells double positive for 11β-hydroxylase and aldosterone synthase ( P<0.0001). Comparing between the cases with and those without KCNJ5 mutation, the KCNJ5-mutated group demonstrated a significantly higher concentration of peripheral 18oxoF (28.4±5.6 versus 3.0±0.9 ng/dL, P<0.0001) and a larger intratumoral environment including the hybrid cells ( P<0.001), possibly representing a deviation from normal aldosterone biosynthesis. After multivariate analysis, KCNJ5 mutation status turned out to be the most associated factor involved in 18oxoF synthesis in APA ( P<0.0001). Results of our present study first revealed that enhanced 18oxoF synthesis in APA could come from a functional deviation of aldosterone biosynthesis from the normal zona glomerulosa and the utility of peripheral 18oxoF measurement could be influenced by the prevalence of KCNJ5 mutation in an APA.

H-score of 11β-hydroxylase and aldosterone synthase in the histopathological diagnosis of adrenocortical tumors

PURPOSE

To assess the diagnostic performance of the H-score of 11β-hydroxylase (CYP11B1) and aldosterone synthase (CYP11B2) in the histopathological diagnosis of adrenocortical tumors (ACT).

METHODS

We retrospectively evaluated 199 cases of ACT, of which 85 were diagnosed as aldosterone-producing adenoma (APA), 66 as cortisol-producing adenoma (CPA), 9 as aldosterone-cortisol co-secreting adenoma, 30 as nonhyperfunctioning adenoma, and 9 as adrenocortical carcinoma (ACC). Immunohistochemical staining was performed using anti-CYP11B1 and anti-CYP11B2 monoclonal antibodies. The staining was quantified by the McCarty's H-score system. The diagnostic performance was assessed by the receiver operating characteristic curve (ROC).

RESULTS

The H-score of CYP11B1 is highest in the CPA group and lowest in the ACC group. The H-score of CYP11B2 in the APA group is significantly higher than other ACT groups. The area under ROC (AUC) of an increased H-score of CYP11B2 (>65) for the diagnosis of APA was 0.971 (95%CI 0.937-0.990). The AUC of an increased H-score of CYP11B1 (>204) for the diagnosis of CPA was 0.725 (95%CI 0.658-0.786). The AUC of a decreased H-score of CYP11B1 (<85) for the diagnosis of ACC was 0.960 (95%CI 0.923-0.983).

CONCLUSIONS

H-score of CYP11B1 and CYP11B2 are reliable tools for the histopathological subtyping of functional benign ACT and may offer some value in the histopathological diagnosis of malignant ACT.

Tumor microenvironment in functional adrenocortical adenomas: immune cell infiltration in cortisol-producing adrenocortical adenoma

The tumor microenvironment plays pivotal roles in various human neoplasms. However, that of benign tumor, particularly hormone-secreting endocrine tumors, has remained virtually unknown. Therefore, we firstly attempted to analyze the tumor microenvironment of autonomous hormone-secreting adrenocortical adenomas. We first histologically evaluated 21 cortisol-producing adrenocortical adenoma (CPA) and 13 aldosterone-producing adrenocortical adenoma (APA) cases. Quantitative histologic analysis revealed that intratumoral immune cell infiltration (ICI) was more pronounced in CPAs than in APAs. We then evaluated the cytokine and chemokine profiles using polymerase chain reaction arrays in APAs and CPAs. Angiogenic chemokines, C-X-C motif chemokine ligand (CXCL) 1 and CXCL2, were significantly more abundant in CPAs than in APAs using subsequent quantitative polymerase chain reaction and immunohistochemical analyses. We then examined the vascular density between these 2 adenomas, and the density was significantly higher in overt CPAs than in APAs. Of particular interest, CXCL12-positive vessels were detected predominantly in CPAs, and their infiltrating immune cells were C-X-C motif chemokine receptor 4 (CXCR4) positive. These results above indicated that CXCL12-CXCR4 signaling could partly account for ICI detected predominantly in CPAs. We then further explored the etiology of ICI in CPAs by evaluating the senescence of tumor cells possibly caused by excessive cortisol in CPAs. The status of senescence markers, p16 and p21, was significantly more abundant in CPAs than in APAs. In addition, all CPA cases examined were positive for senescence-associated β-galactosidase. These results all indicated that exposure to local excessive cortisol could result in senescence of tumors cells and play essential roles in constituting the characteristic tissue microenvironment of CPAs.

Cortisol overproduction results from DNA methylation of CYP11B1 in hypercortisolemia

Adrenocortical hormone excess, due to primary aldosteronism (PA) or hypercortisolemia, causes hypertension and cardiovascular complications. In PA, hypomethylation of aldosterone synthase (CYP11B2) is associated with aldosterone overproduction. However, in hypercortisolemia, the role of DNA methylation of 11β-hydroxylase (CYP11B1), which catalyzes cortisol biosynthesis and is highly homologous to CYP11B2, is unclear. The aims of our study were to determine whether the CYP11B1 expression was regulated through DNA methylation in hypercortisolemia with cortisol-producing adenoma (CPA), and to investigate a possible relationship between DNA methylation and somatic mutations identified in CPA. Methylation analysis showed that the CYP11B1 promoter was significantly less methylated in CPA than in adjacent unaffected adrenal tissue and white blood cells. Furthermore, in CPA with somatic mutations in either the catalytic subunit of protein kinase A (PRKACA) or the guanine nucleotide-binding protein subunit alpha (GNAS) gene, the CYP11B1 promoter was significantly hypomethylated. In addition, DNA methylation reduced CYP11B1 promoter activity using a reporter assay. Our study results suggest that DNA methylation at the CYP11B1 promoter plays a role in the regulation of CYP11B1 expression and cortisol production in CPA, and that somatic mutations associated with CPA reduce DNA methylation at the CYP11B1 promoter.

Inflammation, Stress Response, and Redox Dysregulation Biomarkers: Clinical Outcomes and Pharmacological Implications for Psychosis

In recent years, several studies claiming the finding of a specific biomarker for the identification of the "high-risk state" to develop psychosis, first psychotic episode, as well as the prediction of the individual response to antipsychotics have been published. Together with genetic reports, numerous publications in this field have been focused on inflammation and stress response blood biomarkers, as well as on indicators of redox dysregulation. In this review, we focus on human studies found in PubMed from January 1^st 2010 to January 31^st 2017, describing the clinical use of these biomarkers to detect the "premorbid" psychotic state and early phases of the disease. Their pharmacological implications in predicting and monitoring the individual response to antipsychotic medication is also discussed.