ACTH-independent Macronodular Adrenal Hyperplasia Research Articles

Classification, diagnosis and treatment of ACTH-independent macronodular adrenal hyperplasia

ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a distinctive subtype of Cushing's syndrome (CS), with different clinical manifestations according to the level of serum cortisol. Based on clinical manifestations and serum cortisol, we divide AIMAH into three types, subclinical AIMAH, clinical AIMAH and high-risk AIMAH, with varied treatment methods being adapted to different subtypes. At the same time, we describe 3 patients who represent these subtypes of this disease, and review some cases of AIMAH which have been previously reported in the English literature. To our knowledge, this is the first article discussing classification, diagnosis and treatment of this disease and should be useful for future therapy of AIMAH.

Whole exome sequencing identifies mutation of EDNRA involved in ACTH-independent macronodular adrenal hyperplasia

ACTH independent macronodular adrenal hyperplasia (AIMAH) is a rare disorder characterized by bilateral macronodular hyperplasia of the adrenal glands and increased cortisol production with subclinical or overt Cushing's syndrome. Although the family clustering of AIMAH is infrequent, we have tried our best to find such a familial affected pedigree with complete clinical information and successfully collect adrenalectomy tissue samples from two members of this family. Using whole exome sequencing and several variant prioritization strategies based on disease network analysis, we identified Endothelin receptor type A (EDNRA) Ser420Thr mutation as a causative mutation of AIMAH. EDNRA is a member of G protein coupled receptor family and is involved in cardiovascular or polycystic kidney disease. Our findings indicate that the mutation of EDNRA at S420T site should be regard as a potential AIMAH causative variation in familial and sporadic affected patients.

The Role of Unilateral Adrenalectomy in Corticotropin‐Independent Bilateral Adrenocortical Hyperplasias

The objective of the present study was twofold: to demonstrate our experience with unilateral adrenalectomy in the treatment of adrenocorticotropic hormone (ACTH)-independent Cushing syndrome (CS) caused by bilateral adrenocortical hyperplasias, and to evaluate the long-term results as evidenced by the main laboratory and clinical findings. From February 2000 to August 2009, unilateral adrenalectomy was performed on 27 patients with ACTH-independent CS and bilateral adrenocortical hyperplasias, including 14 patients with ACTH-independent macronodular adrenal hyperplasia (AIMAH) and 13 patients with primary pigmented nodular adrenocortical disease (PPNAD). Signs and symptoms of CS, endocrine examinations, and radiographic imaging were evaluated preoperatively and postoperatively. At a median follow-up of 69 months (range: 23-120 months) for AIMAH and 47 months (range: 16-113 months) for PPNAD, 25 patients were cured by unilateral adrenalectomy. Serum cortisol level, daily urinary free cortisol (UFC), and plasma ACTH regained the normal range in both AIMAH and PPNAD patients at monthly follow-up visits; the circadian serum cortisol rhythm returned to normal, and a normal responsiveness to overnight low-dose dexamethasone administration (LDDST) became obvious. Both systolic and diastolic blood pressure (BP) levels were significantly reduced: 85 % of patients recovered normal BP levels, and the remaining patients need antihypertensive drugs, but at a reduced dose. No surgery-related morbidity occurred, and there was no sign of further enlargement of the residual adrenal gland after successful unilateral adrenalectomy. One patient with PPNAD and another patient with AIMAH with similar weights and sizes of the bilateral adrenals needed contralateral adrenalectomy. Unilateral adrenalectomy may be the suitable treatment for selected patients with AIMAH and PPNAD. It can achieve long-term remission of CS and improve glycemic control and BP values.

ACTH independent bilateral macronodular adrenal hyperplasia presenting as subclinical Cushing's syndrome

ACTH independent bilateral macronodular adrenal hyperplasia presenting as subclinical Cushing's syndrome

Phosphodiesterase 11A (PDE11A) Gene Defects in Patients with ACTH-Independent Macronodular Adrenal Hyperplasia (AIMAH): Functional Variants May Contribute to Genetic Susceptibility of Bilateral Adrenal Tumors

Phosphodiesterases (PDEs) are key regulatory enzymes of intracellular cAMP levels. PDE11A function has been linked to predisposition to adrenocortical tumors. The aim of the study was to study the PDE11A gene in a large cohort of patients with ACTH-independent macronodular adrenal hyperplasia (AIMAH) and in control subjects. The PDE11A entire coding region was sequenced in 46 patients with AIMAH and 192 controls. Two variants found in AIMAH patients were transiently expressed in HEK 293 and adrenocortical H295R cells for further functional studies. The frequency of all PDE11A variants was significantly higher among patients with AIMAH (28%) compared to controls (7.2%) (P = 5 × 10(-5)). Transfection of the two PDE11A variants found in AIMAH patients only (D609N or M878V) showed that cAMP levels were higher, after forskolin stimulation, in cells transfected with the PDE11A mutants, compared to cells transfected with the wild-type PDE11A in HEK 293 cells (P < 0.05). Moreover, transfection with mutants PDE11A increased transcriptional activity of a cAMP-response element reporter construct compared to wild-type PDE11A in HEK 293 cells (P < 0.0004 for D609N and P < 0.003 for M878V) and in the adrenocortical H295R cells (P < 0.05 for D609N and M878V). In addition, analysis of cAMP levels in intact living culture cells by fluorescence resonance energy transfer probes showed increased cAMP in forskolin-treated cells transfected with PDE11A variants compared with wild-type PDE11A (P < 0.05). We conclude that PDE11A genetic variants may increase predisposition to AIMAH.

Adrenal Nodular Hyperplasia in Hereditary Leiomyomatosis and Renal Cell Cancer

The condition hereditary leiomyomatosis and renal cell carcinoma is characterized by cutaneous leiomyomas, uterine fibroids and aggressive papillary renal cell carcinoma. A number of our patients with hereditary leiomyomatosis and renal cell carcinoma had atypical adrenal nodules, which were further evaluated to determine whether these nodules were associated with hereditary leiomyomatosis and renal cell carcinoma. Patients with hereditary leiomyomatosis and renal cell carcinoma underwent a comprehensive clinical and genetic evaluation. We reviewed the clinical presentation, anatomical and functional imaging, endocrine evaluation, pathological examination and germline mutation testing results. Of 255 patients with hereditary leiomyomatosis and renal cell carcinoma 20 (7.8%) had primary adrenal lesions, including 4 with bilateral adrenal lesions and 4 with multiple nodules. Two patients had adrenocorticotropic hormone independent hypercortisolism. A total of 27 adrenal lesions were evaluated. The imaging characteristics of 5 of these lesions (18.5%) were not consistent with adenoma by noncontrast computerized tomography criteria. Positron emission tomography was positive in 7 of 10 cases (70%). A total of 12 nodules were surgically resected from 10 adrenal glands. Pathological examination revealed macronodular adrenal hyperplasia in all specimens. Unilateral and bilateral adrenal nodular hyperplasia was detected in a subset of patients with hereditary leiomyomatosis and renal cell carcinoma. A functional endocrine evaluation is recommended when an adrenal lesion is discovered. Imaging frequently reveals lesions that are not typical of adenomas and positron emission tomography may be positive. To date no patient has had adrenal malignancy, and active surveillance of hereditary leiomyomatosis and renal cell carcinoma adrenal nodules appears justified.

Successful treatment for adrenocorticotropic hormone-independent macronodular adrenal hyperplasia with laparoscopic adrenalectomy: a case series

IntroductionAdrenocorticotropic hormone-independent macronodular adrenal hyperplasia, characterized by bilateral macronodular adrenal hypertrophy and autonomous cortisol production, is a rare cause of Cushing’s syndrome. Bilateral adrenalectomy is considered the standard treatment for adrenocorticotropic hormone-independent macronodular adrenal hyperplasia but obliges the patient to receive lifetime steroid replacement therapy subsequently, and may increase the patient’s risk of adrenal insufficiency. These circumstances require surgeons to carefully consider operative strategies on an individual basis.Case presentationWe performed successful laparoscopic adrenalectomy on four patients with adrenocorticotropic hormone-independent macronodular adrenal hyperplasia. Computed tomography scans showed bilateral adrenal enlargement in all patients. Case 1: a 56-year-old Japanese woman presented with obvious Cushing’s symptoms during treatment for diabetes mellitus and hypertension. Case 2: a 37-year-old Japanese man also presented with Cushing’s symptoms during treatment for diabetes mellitus and hypertension. These patients were diagnosed as Cushing’s syndrome caused by adrenocorticotropic hormone-independent macronodular adrenal hyperplasia based on endocrinologic testing, and underwent bilateral laparoscopic adrenalectomy. Case 3: an 80-year-old Japanese woman was hospitalized due to unusual weight gain and heightened general fatigue, and was diagnosed as Cushing’s syndrome caused by adrenocorticotropic hormone-independent macronodular adrenal hyperplasia. She underwent unilateral laparoscopic adrenalectomy due to high operative risk. Case 4: a 66-year-old Japanese man was discovered to have bilateral adrenal tumors on medical examination. He did not have Cushing’s symptoms and was diagnosed as subclinical Cushing’s syndrome due to suppressed adrenocorticotropic hormone serum levels and loss of cortisol circadian rhythm without abnormal levels of serum cortisol. He underwent unilateral laparoscopic adrenalectomy. During follow-up, serum cortisol levels were within the normal range in all cases, and serum adrenocorticotropic hormone levels were not suppressed. Further, cases with Cushing’s syndrome experienced clinical improvement.ConclusionsWe were able to effectively treat adrenocorticotropic hormone-independent macronodular adrenal hyperplasia in patients with obvious Cushing’s symptoms by laparoscopic bilateral adrenalectomy, which promptly improved symptoms. Further, unilateral adrenalectomy was effective for treating an older patient at high operative risk and a patient with subclinical Cushing’s syndrome.

New developments in the medical treatment of Cushing's syndrome

Cushing's syndrome (CS) is a severe endocrine disorder characterized by chronic cortisol excess due to an ACTH-secreting pituitary adenoma, ectopic ACTH production, or a cortisol-producing adrenal neoplasia. Regardless of the underlying cause, untreated CS is associated with considerable morbidity and mortality. Surgery is the primary therapy for all causes of CS, but surgical failure and ineligibility of the patient to undergo surgery necessitate alternative treatment modalities. The role of medical therapy in CS has been limited because of lack of efficacy or intolerability. In recent years, however, new targets for medical therapy have been identified, both at the level of the pituitary gland (e.g. somatostatin, dopamine, and epidermal growth factor receptors) and the adrenal gland (ectopically expressed receptors in ACTH-independent macronodular adrenal hyperplasia). In this review, results of preclinical and clinical studies with drugs that exert their action through these molecular targets, as well as already established medical treatment options, will be discussed.

Multi-detector-row CT findings of ACTH-independent macronodular adrenal hyperplasia

Objective To explore the characteristics multi-detector-row computed tomography (MDCT)findings of ACTH-independent macronodular adrenal hyperplasia ( AIMAH ).Methods The un-enhanced and contrast-enhanced MDCT features in 24 patients ( 14 males and 10 females) with clinically confirmed AIMAH were retrospectively assessed for the morphology and enhancement patterns.Results The adrenal glands were involved bilaterally in all of the 24 cases( 100％ ).24 patients had massively enlarged multinodular adrenal glands.Nodules were( 1.79 ± 1.02) cm (0.50 ～ 3.85 cm),which usually distorted and completely obscured the normal adrenal glands.The enlarged adrenal glands were still retained the adreniform contour,showed characteristic ginger-like.22 of the 24 ( 91.7 ％ ) hyperplastic nodular glands demonstrated mild homogeneous enhancement.Calcification was revealed in 1 adrenals ( 1/24,4.2％ ).Conclusion MDCT reveals the characteristic morphology and CT attenuation in AIMAH.Combined with its clinical presentation and biochemical findings,AIMAH is able to be diagnosed with high specificity and accuracy on MDCT. Key words: Adrenal glands; Hyperplasia; Adrenocorticotropic hormone; Tomography, X-ray computed

Genome-wide gene expression profiling identifies overlap with malignant adrenocortical tumours and novel mechanisms of inefficient steroidogenesis in familial ACTH-independent macronodular adrenal hyperplasia

"Genome-wide gene expression profiling identifies overlap with malignant adrenocortical tumours and novel mechanisms of inefficient steroidogenesis in familial ACTH-independent macronodular adrenal hyperplasia" published on Jun 2012 by Society for Endocrinology.

Perioperative management of high risk ACTH-independent macronodular adrenal hyperplasia: Report of one case

Objective To improve the diagnosis and treatment of ACTH-independent macronodular adrenal hyperplasia(AIMAH).Methods A 51-year-old female patient with Cushing's syndrome caused by AIMAH was reported.Elevated early morning plasma cortisol levels,increased 24 h urinary free cortisol excretion,and loss of the normal circadian rhythm in cortisol secretion were presented.There was no suppression of cortisol secretion by administration of low-and high-dose overnight dexamethasone suppression test.Cardio-pulmonary function was very bad with the highest blood pressure reaching 300/120 mm Hg( 1 mm Hg=0.133 kPa).Initially,she was treated with mitotane(60 mg/d),but was not effective.After taking ketoconazole (800 mg/d)for 5 days,cardio-pulmonary function was not effectively improved with blood pressure only descending to 180/120 mm Hg.Orthopnoea appeared and Spo2fell once to 75％.The patient had to undergo right total adrenalectomy immediately.Results The mass resected was 10 cm× 10 cm in size and weighted 67.5 g.Histological examination of the removed adrenal revealed nonpigmented macronodular cortical hyperplasia.The patient continued to take ketoconazole (400-800 mg/d)from the 6th day of the operation without steroid replacement therapy in that period.With normal cortisol levels( plasma cortisol at 8:00 was 18.65 μg/dl,24 h urinary free cortisol was 78.75 μmol),she left hospital after the general condition had been improved.During the following updated 10 months follow up,the indexes of her laboratory examination were maintained normal.Conclusion Individualized therapy should be adopted for the patient with AIMAH.The medication is useful to suppress the adrenal gland cortisol production for those with progression of symptoms,very high blood pressure,hypokalemia and hypoproteinemia.Once the cardio-pulmonary function improves,the target organ should be resected as soon as possible.The supplement of cortisol is not appropriate during the perioperative period.The unilateral adrenalectomy is an effective treatment for AIMAH. Key words: ACTH-independent macronodular adrenal hyperplasia; Surgery; Ketoconazole; Plasma cortisol

Usefulness and Limitations of Unilateral Adrenalectomy for ACTH-independent Macronodular Adrenal Hyperplasia in a Patient with Poor Glycemic Control

Adrenocorticotropic hormone (ACTH)-independent macronodular adrenal hyperplasia (AIMAH) is a rare disease which causes Cushing's syndrome. Bilateral adrenalectomy has been recommended as the treatment of choice for AIMAH. However, bilaterally adrenalectomized patients require lifelong steroid replacement therapy. Therefore, an increasing number of patients have undergone unilateral adrenalectomy for AIMAH. We report a case of AIMAH due to refractory diabetes in whom unilateral adrenalectomy initially yielded good diabetes control, but in whom poor glycemic control developed after 5 years, requiring eventual additional contralateral adrenalectomy. In elderly patients with AIMAH, one-stage bilateral adrenalectomy may be the treatment of choice.

A Rare Case of Adrenocorticotropic Hormone (ACTH)-independent Macroadrenal Hyperplasia Showing Ectopic Production of ACTH

A 57-year-old Japanese man presented with drug-resistant hypertension without Cushingoid features. Endocrinological tests revealed autonomous secretion of cortisol with suppressed plasma adrenocorticotropic hormone (ACTH). Imaging examinations showed multiple macronodules in the bilateral adrenal gland. These findings were consistent with subclinical Cushing's syndrome caused by ACTH-independent macronodular adrenal hyperplasia (AIMAH). Left adrenalectomy was performed and the resected adrenal lesion was consistent with the pathological diagnosis of AIMAH. Furthermore, in resected tissue, we demonstrated intraadrenal production of ACTH by immunohistochemical analysis and RIA. This is a very rare case of AIMAH showing ectopic production of ACTH, which may be associated with autonomous cortisol secretion.

Adrenal Incidentalomas with Supraphysiologic Response to ACTH Stimulus: A Case Report

We present the diagnostic approach of a patient with adrenal incidentalomas. A 72-year-old African American male had a CT scan of the abdomen showing right and left adrenal masses measuring 5 × 3.5 cm and 3.7 × 2.9 cm, respectively. The patient had negative hormonal workup. The radiologist insisted that the CT findings are consistent with adrenal hyperplasia, and therefore he underwent ACTH stimulation to rule out late-onset congenital adrenal hyperplasia (CAH). The stimulation test revealed that 17-hydroxyprogesterone and 11-deoxycortisol increased to levels high enough to confirm CAH, but cortisol had exaggerated response as well, thus making the diagnosis of CAH unlikely where metabolism is shifted to precursors. Subsequently, the patient underwent screening for Cushing's syndrome (CS) with a dexamethasone suppression test. Patient failed the suppresion test, raising the issue for subclinical CS (SCS), likely due to ACTH-independent macronodular adrenal hyperplasia. Our patient had been diagnosed with MGUS and so far there are only 3 case reports of extramedullary plasmacytoma arising from the adrenals. One was bilateral and one had functional abnormalities. Our differential diagnosis includes subclinical CS with aberrant receptors versus a functioning extramedullary plasmacytoma.

A study on clinical features of ACTH-independent bilateral macronodular adrenal hyperplasia

Objective To study the clinical features of patients with ACTH-independent bilateral macronodular adrenal hyperplasia(AIMAH).Methods Eighteen cases with AIMAH diagnosed in Chinese PLA General Hospital from 1998 to 2010 were analyzed retrospectively.Results ( 1 ) AIMAH was equally distributed between genders,mean age at diagnosis was ( 51.4 ± 10.7 ) years,and average course was ( 9.9:t:2.7 ) years.( 2 )Most patients visited hospital because of adrenal incidentaloma; hypertension and impaired glucose tolerance/diabetes mellitius were the most common clinical presentations; typical signs of Cushing′s syndrome (CS) such as moon face and central obesity were less frequent.( 3 ) All cases′ laboratory findings met the diagnostic criteria of ACTH-independent CS,some cases with the features of subclinical CS.24 h dynamic plasma ACTH and cortisol monitoring had the advantage of revealing the features of subclinical CS for some AIMAH cases; there was remarkable elevation of plasma cortisol after exogenous ACTH stimulation in AIMAH patients.(4) Bilateral adrenal macronodular changes could be visualized on CT scan.( 5 ) Pathology identified bilateral macronodular adrenal hyperplasia.( 6 ) Bilateral adrenalectomy was the most useful treatment.Conclusions AIMAH is an infrequent cause of CS,and some patients present subclinical CS.Its marked clinical feature is ACTH-independent bilateral macronodular adrenal hyperplasia. Key words: Adrenocorticotrophichormone; Adrenocortical,hyperplasia; Cushing′s syndrome

Surgical treatment of adrenocorticotropin-independent macronodular adrenal hyperplasia

Objective To investigate the diagnosis and treatment of adrenocorticotropin-independent macronodular adrenal hyperplasia (AIMAH). Methods The clinical data of 14 cases of AIMAH from August 1972 to July 2010 were retrospectively analyzed.The cases included 5 males and 9 females with a mean age of 45 (range 26 to 58 ) years.Ten patients demonstrated typical Cushing's syndrome (CS) and 4 patients presented with weight gain,hypertension or diabetes mellitus without any signs of CS.The circadian rhythm of serum cortisol was abnormal.Low and high dose dexamethasone suppression tests failed to suppress cortisol secretion.CT scan showed bilateral enlargement of the adrenal glands with multiple macronodules.All patients underwent open surgery,including 5 cases of unilateral adrenalectomy,6 cases of adrenalectomy combined with contralateral subtotal adrenalectomy and 3 cases of bilateral adrenalectomy.Results It was established by pathological examination that all patients had bilateral adrenal macronodular or adenomatoid hyperplasia.During the mean follow-up of 69 months (range 12 to 120 months),the clinical symptoms of CS disappeared after surgery in all cases.The 5 patients who received unilateral adrenalectomy had urinary free cortisol and serum cortisol within normal ranges and no further enlargement of the contralateral gland was noticed.Among the 3 patients who received bilateral adrenalectomy,1 case died of adrenal crisis on day seven post-operation.The remaining 2 cases presented with adrenal insufficiency but returned to normal after glucocorticoid replacement therapy.Nelson's syndrome was not observed in the other patients.Conclusions AIMAH has unique endocrinological and pathological features,presenting as an independent etiology of CS.Unilateral adrenalectomy appears to be an effective and safe alternative treatment for AIMAH and long-term remission can be achieved.Bilateral adrenalectomy or unilateral adrenalectomy combined with contralateral subtotal adrenalectomy may be performed if the symptoms have not improved or recurred after unilateral adrenalectomy. Key words: Cushing syndrome; Adrenocorticotropic hormone; Macronodular adrenal hyperplasia; Surgical procedures, operative

Assessment of long-term efficacy and safety of metyrapone monotherapy in a patient with ACTH-independent macronodular adrenal hyperplasia

Assessment of long-term efficacy and safety of metyrapone monotherapy in a patient with ACTH-independent macronodular adrenal hyperplasia

Identification of Genetic Alterations ofAXIN2Gene in Adrenocortical Tumors

Mutations of the β-catenin gene (CTNNB1), which lead to constitutive activation of Wnt signaling, have recently been described in adrenocortical adenomas (AA) and carcinomas (ACC). However, somatic CTNNB1 mutations may explain only about 50% of β-catenin accumulation observed in adrenocortical tumors, indicating that other components of the Wnt pathway may be involved. The objective of the study was to investigate whether alterations in AXIN2 may be present in adrenocortical tumors. We studied 49 human adrenocortical samples: 30 AA, six ACC, five primary pigmented nodular adrenocortical disease five ACTH-independent macronodular adrenal hyperplasias (AIMAH), and three ACTH-dependent hyperplasias in addition to the human ACC cell lines SW13 and H295R. Samples were screened for somatic genetic alterations in exon 3 of CTNNB1 and exons 5, 7, and 9 of AXIN2. We found an in-frame, 12-bp deletion beginning at coding nucleotide 2013 in exon 7 of the AXIN2 gene, c.2013_2024del12 (p.Arg671_Pro674del), in two of 30 AA (7%), one of six ACC (17%), and the ACC H295R cell line. Immunohistochemistry revealed that tumors with AXIN2 genetic defects showed nuclear/cytoplasmic accumulation of β-catenin, indicating the activation of Wnt signaling. In addition, the ACC and H295R cells with AXIN2 deletion (c.2013_2024del12) harbored p.Ser45del and p.Ser45Pro CTNNB1 mutations, respectively. Two single-nucleotide polymorphisms were identified in exon 7 of AXIN2, c.2351C>T in 2 AA, and one AIMAH and c.2342A>G in an AIMAH tissue. The present study reports, for the first time, that AXIN2 genetic defects may be found in adrenocortical tumors. However, the functional consequence of this genetic alteration remains to be determined.

Aberrant cortisol responses to physiological stimuli in patients presenting with bilateral adrenal incidentalomas

Aberrant receptors have been implicated in the pathogenesis of several types of adrenal tumours. So far the presence of aberrant receptors has been investigated in patients with massively enlarged adrenals due to ACTH-independent macronodular adrenal hyperplasia (AIMAH) and unilateral adrenal adenomas associated with overt or subclinical Cushing's syndrome. The likelihood of aberrant responses in patients presenting with bilateral adrenal incidentalomas (BI) presenting as discrete solitary bilateral adenomas has not been thoroughly addressed. This is an observational cross-sectional prospective study conducted in a secondary/tertiary care centre. We studied 33 patients; 28 with incidentally discovered bilateral discrete adrenal adenomas and five with massive bilateral adrenal macronodular hyperplasia. We probed responses to physiological stimuli, namely upright posture and meal; in a subgroup of menopausal women the presence of aberrant gonadotropin receptors was assessed by the LHRH test. Abnormal responses obtained in tests performed with no dexamethasone suppression were always repeated and confirmed under dexamethasone suppression. Aberrant cortisol responses were confirmed in 10 patients; 9 to posture, 1 to meal (along with a positive response to posture) and 1 to LHRH tests. Patients who responded to any test compared to those who tested negative had larger adenomas, higher post-LDDST and midnight cortisol and a trend for lower ACTH levels. Patients without subclinical hypercortisolism (SH) did not respond to any test while 50% of patients with SH had an aberrant response (P=0.002). A greater prevalence of aberrant responses was noted in patients with bilateral macronodular hyperplasia compared to those with solitary bilateral adenomas (80 vs. 21.4%, P=0.02). Aberrant cortisol responses, primarily to posture testing, are present in a substantial proportion of patients with bilateral adrenal incidentalomas. Such cortisol responses are observed only in patients with subclinical hypercortisolism and especially in those patients with larger adrenal lesions.

Integrated Genomic Analysis of Nodular Tissue in Macronodular Adrenocortical Hyperplasia: Progression of Tumorigenesis in a Disorder Associated with Multiple Benign Lesions

Massive macronodular adrenocortical disease or ACTH-independent macronodular adrenal hyperplasia (AIMAH) is a clinically and genetically heterogeneous disorder. Whole-genome expression profiling and oligonucleotide array comparative genomic hybridization changes were analyzed in samples of different nodules from the same patients with AIMAH. Quantitative RT-PCR and staining were employed to validate the mRNA array data. Chromosomal gains were more frequent in larger nodules when compared with smaller nodules from the same patients. Among the 50 most overexpressed genes, 50% had a chromosomal locus that was amplified in the comparative genomic hybridization data. Although the list of most over- and underexpressed genes was similar between the nodules of different size, the gene set enrichment analysis identified different pathways associated with AIMAH that corresponded to the size; the smaller nodules were mainly enriched for metabolic pathways, whereas p53 signaling and cancer genes were enriched in larger nodules. Confirmatory studies demonstrated that BCL2, E2F1, EGF, c-KIT, MYB, PRKCA, and CTNNB1 were overexpressed in the larger nodules at messenger and/or protein levels. Chromosomal enrichment analysis showed that chromosomes 20q13 and 14q23 might be involved in progression of AIMAH from smaller to larger tumors. Integrated transcriptomic and genomic data for AIMAH provides supporting evidence to the hypothesis that larger adrenal lesions, in the context of this chronic, polyclonal hyperplasia, accumulate an increased number of genomic and, subsequently, transcript abnormalities. The latter shows that the disease appears to start with mainly tissue metabolic derangements, as suggested by the study of the smaller nodules, but larger lesions showed aberrant expression of oncogenic pathways.