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Introduction: Although 18F-FDG PET was originally developed to evaluate benign and malignant tumors, the frequency of detection of benign adrenocortical adenomas showing FDG-PET accumulation has increased. However, the details of FDG-PET-accumulated benign adrenocortical adenomas have not been elucidated., Methods: To elucidate the pathophysiology of FDG-PET-positive cortisol-producing adrenal tumors, we performed clinicopathological and genetic analyses of adrenocortical adenomas examing FDG-PET in 30 operated patients with unilateral cortisol-producing adrenal tumors (26 adrenal adenomas and 4 adrenal cancers)., Results: All adrenocortical carcinomas and 17/26 (65%) benign adrenocortical adenomas showed high FDG accumulation (SUVmax ≥ 3). In adrenocortical adenomas with high FDG accumulation (SUVmax ≥ 3), SUVmax showed a positive correlation with the CT Hounsfield units. A higher SUVmax showed a clear black adenoma appearance with predominantly compact cells, which exhibited high T1 and T2 signals, a lack of signal drop on out-of-phase imaging on MRI, and less accumulation on 131-I adsterol scintigraphy. Furthermore, RNA-sequencing analysis revealed significant increases in the lysosomal and autophagy pathways and metabolic pathways, including glycolysis through glucose transporter (GLUT) 1 and 3, in black adenomas with high-level FDG accumulation., Discussion: A black adenoma is blackish due to lipofuscin, which accumulates as a result of damaged mitochondria or proteins that escape lysosomal degradation or autophagy. Since FDG in PET is taken up via GLUTs, alteration of the intracellular metabolic dynamics associated with mitochondrial damage in black adenomas may increase PET accumulation., Conclusion: Black adrenal adenomas should be considered with adrenal tumors showing PET accumulation and low lipid contents.

Objective: Accurate assessment and localization of aldosterone-producing adenomas (APAs) are essential for the treatment of primary aldosteronism (PA). Although adrenal venous sampling (AVS) is the standard method of reference for subtype diagnosis in PA, controversy exists concerning the criteria for its interpretation. This study aims to determine better indicators that can reliably predict subtypes of PA., Method: Retrospective, single-cohort analysis including 209 patients with PA who were subjected to AVS. Eighty-two patients whose plasma aldosterone concentrations (PAC) were normalized after surgery were histopathologically or genetically diagnosed with APA. The accuracy of image findings was compared to AVS results. Receiver operating characteristic (ROC) curve analysis between the operated and the no-apparent laterality groups was performed using AVS parameters and loading test for diagnosis of PA., Result: Agreement between image findings and AVS results was 56.3%. ROC curve analysis revealed that the lateralization index (LI) after adrenocorticotropin stimulation cutoff was 2.40, with 98.8% sensitivity and 97.1% specificity. The contralateral suppression index (CSI) cutoff value was 1.19, with 98.0% sensitivity and 93.9% specificity. All patients over the LI and CSI cutoff values exhibited unilateral subtypes. Among the loading test, the best classification accuracy was achieved using the PAC reduction rate after a saline infusion test (SIT) >33.8%, which yielded 87.2% sensitivity or a PAC after a SIT <87.9 pg/mL with 86.2% specificity for predicting bilateral PA., Conclusion: The combined criteria of the PAC reduction rate and PAC after the SIT can determine which subset of patients with APA who should be performed AVS for validation., (© Endocrine Society 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Hashimoto's thyroiditis is the most common cause of hypothyroidism. Patients usually respond well to oral synthetic thyroxine (levothyroxine); however, for unknown reasons some individuals present with treatment-resistant Hashimoto thyroiditis. In cases of cancer and certain infectious diseases, the ATP binding cassette (ABC) transporters have been implicated in multidrug resistance, and we hypothesized and investigated a role of ABC transporters in drug-resistant Hashimoto's thyroiditis., Case Description: The patient whose case we report had a history of Hashimoto's thyroiditis, immune thrombocytopenia, and refractory hypertension, with varying treatment resistance to the oral medications prescribed for each condition. In order to establish or exclude a genetic basis for her illness, we examined the patient's gene expression profiles using peripheral blood leukocytes, and found that ABCG2/BCRPexpression was significantly high compared with healthy volunteers. Also, the increased daunomycin efflux capacity of our patient's lymphocytes was successfully inhibited by fumitremorgin C, a specific ABCG2/BCRP inhibitor, and the patient's level of thyroid-stimulating hormone increased by 248.6% after administration of intact levothyroxine tablets but decreased by 45.1% when tablets were crushed. Her average blood pressure decreased from 166.3/108.5 mmHg to 125.9/78.8 mmHg when switching from intact to crushed losartan tablets., Conclusions: High expression and accelerated efflux transporter activity of ABCG2/BCRP in the small intestine are expected to contribute to the ineffectiveness of orally administered intact tablets in cases with treatment-resistant Hashimoto's thyroiditis, and crushed tablets can be more effective for some of these patients., (© Endocrine Society 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Context: Necrolytic migratory erythema (NME) occurs in approximately 70% of patients with glucagonoma syndrome. Excessive stimulation of metabolic pathways by hyperglucagonemia, which leads to hypoaminoacidemia, contributes to NME pathogenesis. However, the molecular pathogenesis of glucagonoma and relationships between metabolic abnormalities and clinical symptoms remain unclear., Patient: A 53-year-old woman was referred to our hospital with a generalized rash and weight loss. NME was diagnosed by histopathological examination of skin biopsy tissue. Laboratory tests revealed diabetes, hyperglucagonemia, marked insulin resistance, severe hypoaminoacidemia, ketosis, and anemia. Enhanced computed tomography scans detected a 29-mm pancreatic hypervascular tumor, which was eventually diagnosed as glucagonoma. Preoperative treatment with octreotide long-acting release reduced the glucagon level, improved the amino acid profile, and produced NME remission. Surgical tumor excision normalized the metabolic status and led to remission of symptoms, including NME., Interventions: Whole-exome sequencing (WES) and subsequent targeted capture sequencing, followed by Sanger sequencing and pyrosequencing, identified biallelic alteration of death-domain associated protein (DAXX) with a combination of loss of heterozygosity and frameshift mutations (c.553&#95;554del:p.R185fs and c.1884dupC:p.C629fs) in the glucagonoma. Consistently, immunohistochemistry confirmed near-absence of DAXX staining in the tumor cells. Tumor expression of glucagon and somatostatin receptor subtype 2 and 3 messenger RNA was markedly upregulated., Conclusions: This is a report of glucagonoma with biallelic inactivation of DAXX determined by WES. The tumor manifested as glucagonoma syndrome with generalized NME. This case showed the relationship between hypoaminoacidemia and NME status. Further investigations are required to elucidate the underlying mechanisms of NME onset and glucagonoma tumorigenesis.

Context: Pheochromocytoma is a catecholamine-producing tumor that originates from adrenal chromaffin cells and is capable of secreting various hormones, including ACTH., Case Description: A 56-year-old female presented with Cushingoid appearance and diabetic ketoacidosis. Endocrinological examinations demonstrated ectopic ACTH production with hypercortisolemia and excess urinary cortisol accompanied by elevated plasma and urine catecholamines. Computed tomography revealed a large left adrenal tumor with bilateral adrenal enlargement. Metaiodobenzylguanidine scintigraphy revealed abnormal accumulation in the tumor, which was eventually diagnosed as pheochromocytoma with ectopic ACTH secretion with subsequent manifestation of Cushing's syndrome. Ectopic ACTH secretion and catecholamine production were blocked by metyrapone treatment, whereas dexamethasone paradoxically increased ACTH secretion. Left adrenalectomy resulted in complete remission of Cushing's syndrome and pheochromocytoma., In Vitro Studies: Immunohistological analysis revealed that the tumor contained two functionally distinct chromaffin-like cell types. The majority of tumor cells stained positive for tyrosine hydroxylase (TH), whereas a minor population of ACTH-positive tumor cells was negative for TH. Furthermore, gene expression and in vitro functional analyses using primary tumor tissue cultures demonstrated that dexamethasone facilitated ACTH as well as catecholamine secretion with parallel induction of proopiomelanocortin (POMC), TH, and phenylethanolamine N-methyltransferase mRNA, supporting a glucocorticoid-dependent positive-feedback loop of ACTH secretion in vivo. DNA methylation analysis revealed that the POMC promoter of this tumor, particularly the E2F binding site, was hypomethylated., Conclusion: We present a case of ectopic ACTH syndrome associated with pheochromocytoma. ACTH up-regulation with paradoxical response to glucocorticoid, possibly through the hypomethylation of the POMC promoter, exacerbated the patient's condition.

Mechanical stimulation is crucial to bone growth and triggers osteogenic differentiation through a process involving Rho and protein kinase A. We previously cloned a gene (AKAP13, aka BRX) encoding a protein kinase A-anchoring protein in the N-terminus, a guanine nucleotide-exchange factor for RhoA in the mid-section, coupled to a carboxyl region that binds to estrogen and glucocorticoid nuclear receptors. Because of the critical role of Rho, estrogen, and glucocorticoids in bone remodeling, we examined the multifunctional role of Akap13. Akap13 was expressed in bone, and mice haploinsufficient for Akap13 (Akap13(+/-)) displayed reduced bone mineral density, reduced bone volume/total volume, and trabecular number, and increased trabecular spacing; resembling the changes observed in osteoporotic bone. Consistent with the osteoporotic phenotype, Colony forming unit-fibroblast numbers were diminished in Akap13(+/-) mice, as were osteoblast numbers and extracellular matrix production when compared to control littermates. Transcripts of Runx2, an essential transcription factor for the osteogenic lineage, and alkaline phosphatase (Alp), an indicator of osteogenic commitment, were both reduced in femora of Akap13(+/-) mice. Knockdown of Akap13 reduced levels of Runx2 and Alp transcripts in immortalized bone marrow stem cells. These findings suggest that Akap13 haploinsufficient mice have a deficiency in early osteogenesis with a corresponding reduction in osteoblast number, but no impairment of mature osteoblast activity., (© 2015 American Society for Bone and Mineral Research.)