[Interpretation of the 5th edition WHO classification of adrenal cortical tumors]

Non-neoplastic lesions were added in the 5th edition WHO classification of adrenal cortical tumor based on the recent update, including adrenal rests, adrenal cysts, congenital adrenal hyperplasia and adrenocortical nodular disease. A range of tumor concepts were updated or refined based on tumor cell origin, histopathology, oncology and molecular biology. The most significant nomenclature change in the field of adrenal cortical pathology involves the refined classification of adrenal cortical nodular disease, which now includes sporadic nodular adrenocortical disease, bilateral micronodular adrenal cortical disease, and bilateral macronodular adrenal cortical disease. The 5th edition WHO classification endorses the nomenclature of the HISTALDO classification to help the classification of aldosterone producing adrenal cortical lesions, which uses CYP11B2 immunohistochemistry to identify functional sites of aldosterone production. The 5th edition WHO classification does not change the Weiss and Lin-Weiss-Bisceglia histopathologic criteria for diagnosing adrenal cortical carcinomas, and underscores the diagnostic and prognostic impact of angioinvasion in these tumors. Reticulin algorithm and Helsinki scoring system were added to assist the differential diagnosis of adrenal cortical neoplasms in adults. Pediatric adrenal cortical neoplasms are assessed using the Wieneke system. The 5th edition WHO classification places an emphasis on an accurate assessment of tumor proliferation rate using both the mitotic count (mitoses per 10 mm2) and Ki-67 labeling index which play an essential role in the dynamic risk stratification of affected patients. This review highlights advances in knowledge of histological features, ancillary studies, and associated genetic findings that increase the understanding of the adrenal cortex pathologies in the 5th edition WHO classification.

Diagnostic and prognostic utility of SF1, IGF2 and p57 immunoexpression in pediatric adrenal cortical tumors

BACKGROUND

Adrenocortical tumors (ACT) are uncommon in the pediatric age group. Using the standard Weiss criteria in pediatric tumors leads to overdiagnosis. This has led to the development of newer systems such as Weineke criteria. Ki67 labeling index aids in differentiating adenomas from carcinomas. We aim to evaluate the diagnostic and prognostic role of Ki67 labeling index, along with immunoexpression of steroidogenic factor-1, insulin like growth factor 2 and p57, in pediatric ACTs diagnosed using Weineke criteria.

METHODS

We have studied 25 cases of pediatric ACTs. Immunohistochemical staining for Ki67, SF-1, IGF2 and p57 was done in all cases and the result was correlated with the morphological diagnosis using the Weineke criteria.

RESULTS

Ki67 labeling index showed complete concordance with the morphological diagnosis. SF-1 and IGF2 showed similar correlation with the diagnosis, with IGF-2 proving to be a more specific marker. Increased Ki67, SF-1 and IGF2 immunostaining also correlated with worse survival. p57 was more specific in determining benign status of a tumor.

CONCLUSION

SF-1 and IGF2 are highly sensitive markers of malignancy in pediatric ACTs and can be used in combination with Ki67 expression for optimal diagnostic and prognostic assessment of pediatric ACTs.

TYPE OF STUDY

Prognosis study.

LEVEL OF EVIDENCE

Level II.

ERCC1 as predictive biomarker to platinum-based chemotherapy in adrenocortical carcinomas

OBJECTIVE

Platinum-based chemotherapy (PBC) is the most effective cytotoxic treatment for advanced adrenocortical carcinoma (ACC). Excision repair cross complementing group 1 (ERCC1) plays a critical role in the repair of platinum-induced DNA damage. Two studies investigating the role of ERCC1 immunostaining as a predictive marker for the response to PBC in ACC had reported conflicting results. Both studies used the ERCC1-antibody clone 8F1 that later turned out to be not specific. The aim of this study was to evaluate the predictive role of ERCC1 with a new specific antibody in a larger series of ACC.

DESIGN AND METHODS

146 ACC patients with available FFPE slides were investigated. All patients underwent PBC (median cycles = 6), including cisplatin (n = 131) or carboplatin (n = 15), in most cases combined with etoposide (n = 144), doxorubicin (n = 131) and mitotane (n = 131). Immunostaining was performed with the novel ERCC1-antibody clone 4F9. The relationship between ERCC1 expression and clinicopathological parameters, as well as best objective response to therapy and progression-free survival (PFS) during PBC was evaluated.

RESULTS

High ERCC1 expression was observed in 66% of ACC samples. During PBC, 43 patients experienced objective response (29.5%), 49 stable disease (33.6%), 8 mixed response (5.5%) and 46 progressive disease (31.5%) without any relationship with the ERCC1 immunostaining. No significant correlation was also found between ERCC1 expression and progression-free survival (median 6.5 vs 6 months, P  =  0.33, HR = 1.23, 95% CI = 0.82-2.0).

CONCLUSION

ERCC1 expression is not directly associated with sensitivity to PBC in ACC. Thus, other predictive biomarkers are required to support treatment decisions in patients with ACC.

Analysis of histological and immunohistochemical patterns of benign and malignant adrenocortical tumors by computerized morphometry

Diagnosis of benign and purely localized malignant adrenocortical lesions is still a complex issue. Moreover, histology-based diagnosis may suffer of a moment of subjectivity due to inter- and intra-individual variations. The aim of the present study was to assess, by computerized morphometry, the morphological features in benign and malignant adrenocortical neoplasms. Eleven adrenocortical adenomas (ACA) were compared with 18 adrenocortical cancers (ACC). All specimens were stained with H&E, cellular proliferation marker Ki-67 and reticulin. We generated a morphometric model based on the analysis of volume fractions occupied by Ki-67 positive and negative cells (nuclei and cytoplasm), vascular and inflammatory compartment; we also analyzed the surface fraction occupied by reticulin. We compared the quantitative data of Ki-67 obtained by morphometry with the quantification resulting from pathologist's visual reading. The volume fraction of Ki-67 positive cells in ACCs was higher than in ACAs. The volume fraction of nuclei in unit volume and the nuclear/cytoplasmic ratio in both Ki-67 negative cells and Ki-67 positive cells were prominent in ACCs. The surface fraction of reticulin was considerably lower in ACCs. Our computerized morphometric model is simple, reproducible and can be used by the pathologist in the histological workup of adrenocortical tumors to achieve precise and reader-independent quantification of several morphological characteristics of adrenocortical tumors.

Prostate-Specific Membrane Antigen Is a Potential Antiangiogenic Target in Adrenocortical Carcinoma

CONTEXT

Adrenocortical carcinoma (ACC) is a rare tumor type with a poor prognosis and few therapeutic options.

OBJECTIVE

Assess prostate-specific membrane antigen (PSMA) expression as a potential novel therapeutic target for ACC.

DESIGN

Expression of PSMA was evaluated in benign and malignant adrenal tumors and 1 patient with metastatic ACC.

SETTING

This study took place at a tertiary referral center.

PATIENTS

Fifty adrenal samples were evaluated, including 16 normal adrenal glands, 16 adrenocortical adenomas, 15 primary ACC, and 3 ACC metastases.

MAIN OUTCOME MEASURES

Demographics, PSMA expression levels via real-time quantitative polymerase chain reaction and immunohistochemistry and whole-body positron emission tomography-computed tomography standardized uptake values for 1 patient.

RESULTS

qPCR demonstrated an elevated level of PSMA in ACC relative to all benign tissues (P < .05). Immunohistochemistry localized PSMA expression to the neovasculature of ACC and confirmed overexpression of PSMA in ACC relative to benign tissues both in intensity and percentage of vessels stained (78% of ACC, 0% of normal adrenal, and 3.27% of adenoma-associated neovasculature; P < .001). Those with more than 25% PSMA-positive vessels were 33 times more likely to be malignant than benign (odds ratio, P < .001). Whole-body positron emission tomography-computed tomography imaging showed targeting of anti-PSMA Zr89-J591 to 5/5 of the patient's multiple lung masses with an average measurement of 3.49 ± 1.86 cm and a standardized uptake value of 1.4 ± 0.65 relative to blood pool at 0.8 standardized uptake value.

CONCLUSIONS

PSMA is significantly overexpressed in ACC neovasculature when compared with normal and benign adrenal tumors. PSMA expression can be used to image ACC metastases in vivo and may be considered as a potential diagnostic and therapeutic target in ACC.

Ectopic adrenal cortical adenoma in the gastric wall: Case report

Ectopic adrenal cortical neoplasms are extremely rare. Ectopic adrenocortical tissue can be found in locations such as the celiac axis, the broad ligament, the adnexa of the testes, and the spermatic cord; however, they rarely involve the stomach. We report an unusual case of a patient with an ectopic adrenal cortical adenoma in the gastric wall. The patient was a 72-year old female admitted to our hospital with upper abdominal discomfort. Physical examination revealed tenderness below the xiphoid process. Both computed tomography and fibergastroscopy revealed a mass on the lesser curvature side of the gastric antrum; it was initially diagnosed as a gastric stromal tumor. After adequate preparation, the patient underwent surgery. During the procedure, we found a 30 mm × 30 mm mass with medium density in the lesser curvature near the gastric antrum within the serosa. Following immunohistochemistry examination, we corrected the diagnosis to an ectopic adrenal cortical adenoma; the tumor was nonfunctional.

Cushing syndrome and adrenal carcinoma: a clinical case

A 21-year-old girl arrived at our hospital with a short history of hirsutism, facial pletora, amenorrhea, progressive weight gain and hypertension. The clinically suspected Cushing syndrome was then confirmed through chemical pathology. In fact, the results from hemato-chemical exams were: 45.5 Ig/dl cortisol, a DHEA sulphate >8000 ng/ml, 7.2 pg/ml ACTH, 17OH-Progesterone 10.66 ng/ml, Delta-4 Androstenedione 5.2 ng/ml, UFC (Urine Free Cortisol) >1000 mg/24h, FSH 0.8 mUI/ml, LH < 0.1 mUI/ml, Prolactin 13, 17, estradiol 96 pg/ml, and a bonded hypokalaemia, K+ 2,4 mEq/L. The echogram of the complete abdomen reveals, near the superior pole of the left kidney, the presence of a solid mass, not independent from the pole itself about 9.5 centimetres long, diagnosis confirmed to the TC abdomen and pelvis too, with or without mdc. This removed mass resulted, from the histological exam, in an adrenal carcinoma with a general and trabecular structure. Primal adrenal tumours are responsible for about 10% of Cushing syndrome cases. They present an annual incidence of 0.5 - 2.0 cases per million of inhabitants. The prognosis of adrenal ca remains low, with 5 year survival rate for 38% of diagnosed patients.

Adrenocortical oncocytoma in a child

Adrenocortical oncocytoma is a rare epithelial tumor only described in adults. We report the case of a 12-year-old female who presented a left adrenal mass with abdominal pain, fatigue, acne vulgaris, and elevation of the androstenedione and total testosterone. She had an adrenalectomy. A diagnosis of adrenocortical oncocytoma was made after detailed histological, immunohistochemical, and ultrastructural studies.

Myxoid variant of adrenocortical carcinoma: report of a unique case

Myxoid variant of adrenocortical carcinomas (ACC) are rare, there being only 11 cases in the literature to date. Reported herein are the findings of a case, which in contrast to all previously reported myxoid ACC, was devoid of typical non-myxoid areas. The patient was a 61-year-old man in whom a left adrenal mass was detected during investigation of Cushing's syndrome. The adrenal was replaced by malignant cells and expanses of myxoid material. The cells were positive for melan-A, synaptophysin, vimentin and alpha-inhibin. The ultrastructural features of the cells were typical of adrenal cortical differentiation. The differential diagnosis of myxoid ACC includes extraskeletal myxoid chondrosarcoma, chordoma, myxoid adenocarcinoma, myxoma, lipomatous tumors, nerve sheath tumors, smooth muscle tumors, gastrointestinal stromal tumor and other sarcomas. The presence of myxoid material in a retroperitoneal lesion raises a broad differential diagnosis in which myxoid adrenocortical neoplasms should be included. Clinicoradiological correlation may be helpful, but special stains, immunohistochemistry and ultrastructural examination may be necessary to establish the diagnosis.

Recent advances in histopathology and immunohistochemistry of adrenocortical carcinoma

Discerning malignancy in resected adrenocortical neoplasms can pose diagnostic difficulty. Macroscopic examination is the first important step toward diagnosis and should include accurate measurement of weight and dimension of the specimens and description of the cut surface of the tumors. It is also important to sample the specimens for histological diagnosis near foci of hemorrhage and/or necrosis. Histological scoring systems evaluating multiple parameters, especially the criteria of Weiss, have been shown to be reliable in differential diagnosis between adrenocortical adenoma and carcinoma. A tumor is defined as adrenocortical carcinoma when three or more of the following criteria are met; (1) high nuclear grade, (2) mitotic rate six or more per 50 high power fields, (3) atypical mitosis, (4) clear cells less than 25%, (5) a diffuse architecture pattern in more than one-third of the tumor, (6) confluent necrosis, (7) venous invasion, (8) sinusoidal invasion, and (9) capsular invasion. The criteria are relatively straightforward and considered the most effective standard for diagnosis of adrenocortical malignancy. However, great care should be taken in applying the criteria to histological evaluation of two relatively rare and peculiar adrenocortical tumors, adrenocortical oncocytoma and pediatric adrenocortical neoplasms. At this juncture, ancillary biological or molecular markers are of little practical value in terms of differential diagnosis between adrenocortical adenoma and carcinoma but tumors with MIB1 or Ki-67 labeling index more than 2.5 may be considered malignant. Prognostic markers of adrenocortical carcinoma have not been established other than complete respectability of the tumor. There are also no surrogate markers for predicting response to therapy with Mitotane, an adrenolytic agent. It sometimes is important for surgical pathologists to differentiate adrenocortical carcinoma from metastatic malignancies of other sites. An immunohistochemical evaluation of adrenal 4 binding protein (Ad4BP) or SF-1, a transcription factor of all steroidogenesis, can aid in this differential diagnosis because nuclear immunoreactivity for this transcription factor is relatively specific to steroid producing cells.

Adrenocortical Tumors in Brazilian Children: Immunohistochemical Markers and Prognostic Factors

Context.—The behavior of adrenocortical tumors (ACTs) is usually difficult to establish in childhood, and the role of immunomarkers in predicting outcome has not yet been elucidated.

Objective.—To investigate the relationship between clinical, pathologic, and immunohistochemical findings and prognosis in a series of children with ACTs.

Patients and Methods.—Clinical data were evaluated retrospectively in 33 children with ACTs, including age at diagnosis, sex, time between first symptoms and diagnosis, clinical signs and symptoms, tumor position, and follow-up. Histologic sections were reviewed, each tumor was classified, and staging was performed according to previously published criteria. Immunohistochemical analysis of p53, Ki-67, c-Erb-B2, and Bcl-2 was performed according to previously published techniques.

Results.—Sixty-four percent (n = 21) of the patients were female, and the age at diagnosis in the cohort ranged from 2 to 96 months. Virilization alone affected 70% (n = 23) of the patients, and 18 patients had stage 1 disease, 9 had stage 2 disease, and 3 each had stage 3 and stage 4 disease. Female sex and stage 1 and stage 2 disease were associated with good outcome. None of the histopathologic criteria evaluated correctly predicted outcome. Only tumors with a volume exceeding 200 mL were associated with malignant behavior. Because only a small number of tumors expressed the antigens, results of these immunohistochemical tests were considered inconclusive.

Conclusion.—In this sample of pediatric ACTs, the clinical and surgical parameters are the most important prognostic factors, while the immunohistochemical markers evaluated were not predictive of outcome.

Oncocytic adrenocortical carcinomas: a pathological and immunohistochemical study of four cases in comparison with conventional adrenocortical carcinomas

Clinicopathological features of four cases of oncocytic adrenocortical carcinomas were studied. All tumors were large, circumscribed tumors with average size and weight of 11.5 cm and 586 g, respectively. The cut surfaces were yellow or brown and tan with areas of hemorrhage, necrosis, fibrosis, myxoid and cystic change. The tumor cells were exclusively oncocytic with a diffuse or compact and solid arrangement. Nuclear atypia was identified but mitosis was rare. Capsular invasion was identified in all tumors and vascular invasion was identified in one tumor. All tumors were immunoreactive for vimentin and inhibins. Immunoreactivity for pancytokeratin, synaptophysin and S-100 protein was variable and focal. All tumors had low proliferative indices, of less than 1%, and were negative for p53 protein. Ultrastructurally, the cytoplasm of tumor cells showed numerous mitochondria in a compact arrangement. Oncocytic adrenocortical carcinomas showed a similar sex ratio, slightly older mean age, similar left predilection, slightly smaller size and lighter weight compared with the conventional carcinomas. We suggest that most oncocytic adrenocortical carcinomas might be low-grade malignancies with less aggressive histological features compared with conventional carcinomas. However, they should be excised completely because of the likelihood of recurrence and metastasis during the follow-up period.

Corticotropin-releasing hormone receptor expression on normal and tumorous human adrenocortical cells

Corticotropin-releasing hormone (CRH) is not only the principal regulator of the central hypothalamic-pituitary-adrenal (HPA) axis but also exerts direct actions on peripheral tissues. We analyzed the expression of CRH receptors in microdissected preparations of normal human adrenal glands and in adrenocortical and adrenomedullary tumors, employing immunohistochemistry, quantitative RT-PCR of microdissected adrenal tissues, and in situ hybridization. The effect of CRH on adrenal steroidogenesis was tested in adrenal cells. Immunoreactive CRH1R was found primarily within the zona reticularis. In addition, we found a higher expression of CRH type-1 and 2 receptors mRNAs in preparations of adrenal cortices as compared to pheochromocytomas, a 6-fold increase in preparations of clinically unapparent adrenocortical adenomas, and a 10- to 60-fold increase in cortisol-producing adrenal adenomas. Stimulation of the adrenal tumor cell line NCI-H295R with CRH elicited a 1.4-fold increase in DHEA secretion. This result could be reproduced in a culture of primary human adrenocortical cells. We conclude that adrenocortical cells exhibit a higher expression of functional CRH receptors than chromaffin cells and that CRH acts on adrenal DHEA production. The data support the assertion of a direct action of CRH on human adrenocortical cells in addition to an intra-adrenal CRH receptor/adrenocorticotropin system. Enhanced CRH1R expression may be involved in adrenocortical tumorigenesis.

[Oncocytic adrenocortical neoplasms]

Oncocytic neoplasms of the adrenal gland are rare, as described in literature. Only 27 cases have been reported up to now in world literature. Here we describe our experience. In this report we discuss the clinicopathologic and immunohistochemical findings of three oncocytic tumors of the adrenal cortex. Two tumors were found during examination of the patients for other reasons. These tumors were hormonally inactive. One tumor manifested by the virilization of the patient. Immunohistochemical examination demonstrated in all tumors focal positivity with antibodies to neuron-specific enolase and synaptophysin and mostly focally weak positivity for cytokeratins. Very low mitotic activity was found in two tumors. Criteria for evaluation of biological character of this type of tumors are not established.

Cyclin E correlates with malignancy and adverse prognosis in adrenocortical tumors

OBJECTIVE

In many cases, the prognosis of an adrenocortical tumor cannot be determined from pathologic findings alone. We investigated cyclin E levels as a potential marker.

METHODS

We studied 57 tumors by immunohistochemical staining with an anticyclin E antibody. We also evaluated clinical and pathologic factors (McFarlane staging and Weiss score) and previously validated genetic markers (17p13 loss of heterozygosity, 11p15 uniparental disomy, and overexpression of the IGF-II gene) for these tumors. Disease-free survival was estimated in 49 patients who underwent curative surgery.

RESULTS

Cyclin E overproduction (> or =5%) was associated with the malignant phenotype and was strongly correlated with tumor size (P<0.0001), Weiss score (P<0.0001) and the presence of genetic abnormalities in tumors (P<0.001) (nonparametric Wilcoxon test and Fisher's exact test). Within a median follow-up of 44.1 months, seven patients exhibited a recurrence and two patients died from other causes. Cyclin E overproduction was significantly associated with shorter disease-free survival in univariate analysis (P=0.016; RR: 7.6), as were histologic grade (Weiss score > or =4; P=0.0006; RR: 18), 17p13 LOH (P=0.014, RR: 14.9), 11p15 UPD (P=0.003, RR: 11.8) and overexpression of the IGF-II gene (P=0.015, RR: 13.8).

CONCLUSION

This study shows that cyclin E overproduction is of adverse prognostic significance in adrenocortical tumors.

Adrenocortical tumours in children and adults: a study of pathological and proliferation features

AIMS

To demonstrate the correlation between morphological and proliferation parameters with the biological behaviour of adrenocortical tumours (ACTs) in different age groups.

METHODS

Seventy-six cases of ACT were evaluated comparing tumours of children (< or =15 years, n=24) and adults (>15 years, n=52) regarding morphological features and proliferation rates. These parameters were also compared in clinically benign (CB) and clinically malignant (CM) tumours. Tumours were analysed according to Weiss' histological parameters. Proliferation rates were assessed by MIB-1 labelling index and silver binding nucleolar organiser regions (AgNORs) were quantified by image analysis.

RESULTS

ACTs in children presented higher proliferative activity than in adults. In adult's ACTs, MIB-1 labelling index (cut-off, 10%) (P=0.037) and the AgNOR pattern (P<0.001) had influence over the disease-free survival (DFS). The AgNOR pattern type I was associated with CB-ACT and the AgNOR pattern type II with CM-ACT. The AgNOR pattern type III was characteristic of children's ACTs and type IV was characteristic of non-neoplasic adrenal glands.

CONCLUSION

ACTs in children had a different morphological spectrum and higher proliferative activity than those tumours in adults, which should be always analysed as a separate group. In adults, our findings reinforce that the morphological criteria proposed by Weiss are an efficient way of differentiating CB-ACT from CM-ACT.

Pseudoglandular Myxoid Adenoma of the Adrenal Gland

Myxoid tumors of the adrenal cortex are rare. To the best of our knowledge, only 17 cases have been reported to date, including 10 carcinomas and 7 adenomas. The myxoid areas of these tumors are often evident grossly, and their extent is variable. We report on a case of a myxoid adenoma of the right adrenal gland in a 45-year-old male with a prominent pseudoglandular arrangement in more than 90% of the tumor mass, and with a minor component represented by anastomosing cords of tumor cells floating in pools of myxoid material. In addition, after extensive examination, we found foci of typical adrenocortical adenoma. Grossly, the tumor was yellowish without discernable gelatinous changes. Most of the tumor cells had a moderate amount of clear vacuolated cytoplasm and contained numerous oil-red-O-positive lipid droplets. Extracellularly, in the lumens of pseudoglands and on the background, we noticed myxoid material that stained positively with Alcian blue (pH 2.5) and weakly positively with mucicarmine and the PAS method. Immunohistochemical examination showed positivity of the tumor cells for vimentin and cytokeratin CAM5.2. Synaptophysin was weakly positive only focally. Cytokeratin AE1/AE3, EMA, and CEA were negative.

Angiogenesis in human normal and pathologic adrenal cortex

The angiogenic phenotype of 13 normal adrenal glands (N), 13 aldosterone-producing adenomas (APA), 12 cortisol-producing adenomas (CPA), 13 nonfunctioning adrenal cortical adenomas (NFA), and 13 adrenal cortical carcinomas (CA) was investigated. Intratumoral vascular density was explored by CD34, a marker of endothelial cells, and the angiogenic status was investigated by vascular endothelial growth factor (VEGF) expression, an important angiogenic factor expressed by tumoral cells. Vascular density, quantified as the number of vessels per square millimeter, was significantly lower (P < 0.0001) in CA (110.3 +/- 27.8) than in N (336.6 +/- 14.5), APA (322.8 +/- 19.1), CPA (288.5 +/- 14.3), and NFA (274.2 +/- 19.8). VEGF expression, calculated as the percentage of positive cells, was significantly greater (P < 0.0001) in CA (85.3 +/- 2.1) than in APA (56.5 +/- 7.5), CPA (38.5 +/- 7.0), N (33.1 +/- 6.1), and NFA (0.76 +/- 0.6). In APA, a negative relation between CD34 and plasma renin activity (P < 0.0002) and a positive association between CD34 and aldosterone levels (P < 0.05) was found. In conclusion, the angiogenic phenotype of CA is characterized by VEGF overexpression but low vascularization, a finding suggesting a dissociation between angiogenic potential and neoangiogenic capabilities of these tumors. The lack of VEGF expression in NFA and the close association between angiogenesis and functional status in APA also suggest a possible influence of the angiogenic phenotype on hormonal secretion of these endocrine tumors.

Three vasoactive peptides, endothelin-1, adrenomedullin and urotensin-II, in human tumour cell lines of different origin: expression and effects on proliferation

Evidence has accumulated showing that vasoactive peptides, such as endothelin-1, adrenomedullin and urotensin-II, are expressed in various kinds of tumour cells. In the present study, the expression of endothelin-1 and endothelin receptors was studied in eight human tumour cell lines: T98G (glioblastoma), IMR-32 and NB69 (neuroblastoma), BeWo (choriocarcinoma), SW-13 (adrenocortical carcinoma), DLD-1 (colonic carcinoma), HeLa (cervical carcinoma) and VMRC-RCW (renal carcinoma). Reverse transcriptase-PCR showed expression of endothelin-1 mRNA in seven out of the eight cell lines, the exception being BeWo cells. ET(A) receptor mRNA was expressed in T98G, IMR-32 and NB69 cells, but weakly in the other cells. ET(B) receptor mRNA was expressed in IMR-32, NB69 and BeWo cells, but only weakly in T98G and HeLa cells. Immunoreactive endothelin was detected in the culture media of six out of the eight cell lines, but not in that of IMR-32 or BeWo cells. Treatment of T98G cells with an anti-endothelin-1 antibody or an anti-adrenomedullin antibody for 24 h decreased cell numbers to approx. 84% and 90% of control respectively. Treatment with the ET(A) receptor antagonist BQ-610 (1 microM) significantly decreased cell number to about 90% of control, whereas the ET(B) receptor antagonist BQ-788 had no significant effect. On the other hand, exogenously added endothelin-1, adrenomedullin or urotensin-II (0.1 microM) had no significant effects on cell number. These results suggest that endothelin-1 acts as a paracrine or autocrine growth stimulator in tumours. The effect of endothelin-1 on tumour growth appears to be mediated by the ET(A) receptor.

Aberrations of centrosomes in adrenocortical tumors

The frequent and generalized chromosomal imbalances that are characteristic of adrenocortical carcinomas suggest that incomplete chromosome segregation often takes place in these tumors. As a step towards elucidating the mechanism behind the multiple numerical chromosomal aberrations, we have evaluated a series of 14 such tumors for centrosome abnormalities using immunohistochemical detection of the gamma-tubulin centrosome component. The proportion of cells with more than the expected number of 2 centrosomes was moderately increased in the 4 adenomas (1-7%), while a high increase was observed in the 10 carcinomas (1-19%), as compared to the normal reference tissues (0.3%) (p<0.001). Similarly, the centrosome amplification tended to be more pronounced in the carcinomas where the aberrant cells carried 3 or 4 positive signals in 9 of the 10 tumors, and 6 signals were recorded in one tumor, while in the adenomas more than 3 signals was only recorded in one of the 4 cases. The findings demonstrate that centrosome amplifications occur frequently in both adrenocortical adenomas and carcinomas, thus supporting its role in driving the tumor development as opposed to being a consequence of it. Furthermore, the more pronounced occurrence in the malignant form as well as in the larger tumors, offers one likely explanation for the increasing generalized aneuploidy observed during the tumor development, and points to new therapeutic strategies aimed at restoring normal centrosome function.

Apoptosis control and proliferation marker in human normal and neoplastic adrenocortical tissues

We evaluated by immunohistochemistry the expression of the Bcl-2 and p53 proteins, as markers of apoptosis control, and of MIB-1, as a marker of cell proliferation, in a series of normal and neoplastic adrenocortical tissues. The specimens were 13 normal adrenals, 13 aldosterone-producing adenomas, 13 non-functioning adenomas and 16 carcinomas. Results were calculated as percentage of immunostained cells by using specific antibodies. No p53 protein was detected in any of the adrenocortical adenomas (functioning and non functioning) or normal adrenals, while p53 was overexpressed in 15 out of 16 carcinomas. In particular, 10 adrenal cancer specimens (62.5%) showed strong staining in a high percentage (range 10-50%) of the malignant cells. The percentage of Bcl-2 positive cells was higher (P<0.05 or less) in non-functioning adenomas (8.1+/-1.9%) and in carcinomas (14.9+/-5.6%) than in normals (2.9+/-0.9%) and aldosterone-producing adenomas (5.3+/-1.3%) since four specimens of the non-functioning adenomas-group (30.7%) and six of the carcinomas-group (37.5%) showed over 10% positivity (cut-off for normal values, set at 90th percentile of our controls). MIB-1 positivity was 0.50+/-0.36% in normals, 0.54+/-0.08% in non-functioning adenomas and 0.54+/-0.08% in aldosterone-producing adenomas. MIB-1 was expressed in all carcinomas with values (13.7+/-3.1%) significantly (P<0.0006) higher than in the other groups. In conclusion, the present data indicate that the apoptosis control and proliferation activity evaluated by the p53 and MIB-1 proteins are impaired in adrenal carcinomas but preserved in adenomas, independently of their functional status. Therefore, these immunohistochemical markers, overexpressed in carcinomas only, may be useful in the diagnosis of malignancy in adrenocortical tumours. Whether Bcl-2 positivity found in some carcinomas and non-functioning adenomas may constitute, in the latter, a negative prognostic marker is still unknown.

Morphometric analysis, at electron microscope level, combined with hormone assay of nonfunctioning adrenocortical adenomas: comparison with aldosterone-producing adenomas

We performed electron microscopic studies of eight nonfunctioning adrenocortical adenomas (NFA) and nine aldosterone-producing adenomas (APA) obtained from surgical specimens. A comparison of these two types of adenomas was conducted by morphometric analysis of random electron micrographs. The organelles measured included mitochondria (M), smooth-surfaced endoplasmic reticulum (SER), rough-surfaced endoplasmic reticulum (RER), lipid vacuoles (LV), and lysosomes (Ly). The content of steroid hormones, including 17-alpha hydroxyprogesterone (17-OHP), aldosterone (Ald), and other steroid hormones, was measured in adenoma tissue from six NFA and eight APA. The percentages of the areas of the organelles M, SER, and RER per total cell area in the NFA were significantly lower than those in the APA. The average content of Ald in adenoma tissues in APA was markedly higher than that in the NFA, while the mean content of 17-OHP in the NFA was significantly higher than that in APA. In conclusion, NFA are morphometrically characterized by a reduction in organelles such as M, SER, and RER, compared with findings in APA. From the quantitative analysis of steroid hormones, it was suggested that NFA produce more precursor substances with less hormone activity than APA and that steroidgenesis in NFA is shifted to a glucocorticoid pathway, as indicated by the elevated 17-OHP concentration.

Myxoid adrenal cortical adenoma

Myxoid adrenal cortical adenoma is a rare tumor and, to our knowledge, only 16 cases have been reported. We present the case of a 56-year-old Japanese man who was admitted to hospital because of a right adrenal mass that was discovered during a routine physical examination. The resected mass was well circumscribed and contained canary yellow multinodular regions that were surrounded by a brown gelatinous region. Histologically, the multinodular regions resembled a conventional adrenal cortical adenoma, being composed of solid aggregates of large clear or eosinophilic cells. In the gelatinous region, anastomosing small eosinophilic or vesicular cells were visible within a myxoid stroma that contained large amounts of acidic mucopolysaccharides. Light-microscopic findings were consistent with a diagnosis of adenoma. Immunohistochemical staining revealed that a small number of tumor cells were positive for vimentin, and the MIB-1 labeling index was less than 1%. Flow cytometry demonstrated that cells were diploid. At the ultrastructural level, many fat droplets were found in the large clear cells in the multinodular regions. Small eosinophilic cells in the myxoid region contained many mitochondria but few fat droplets. There were no findings suggestive of malignancy. Although the adrenal cortex might have the potential to produce connective tissue-type mucin as a consequence of its mesodermal origin, the mechanism of production of acidic mucopolysaccharides in a myxoid adrenal cortical tumor remains to be clarified.

Differential expression of menin in various adrenal tumors. The role of menin in adrenal tumors

BACKGROUND

Adrenocortical tumors occur as sporadic tumors, as part of the multiple endocrine neoplasia type 1 (MEN1) syndrome, or as part of other hereditary disorders. MEN1 is a tumor suppressor gene located on chromosome 11q13 that encodes a 610-amino acid protein called menin, and plays an important role in the development of MEN1 syndrome. Recent reports indicate that heterozygous germline mutations of this gene are responsible for the disease onset of MEN1.

METHODS

To investigate the role of menin in sporadic adrenocortical tumors, the authors examined a series of adrenocortical adenoma cases and a single case of carcinoma and adrenomedulary tumors with the corresponding adjacent tumor tissues using reverse transcriptase-polymerase chain reaction (RT-PCR) for menin mRNA and Western blot analysis for menin protein. Both RNA and protein from these tumors were applied to RT-PCR and Western blot analysis, respectively, although they are not truly quantitative. Primers for RT-PCR were designed to amplify the sequence between exons 2 and 3 of the MEN1 gene. A specific antibody against menin was generated in guinea pigs immunized with the recombinant peptide from the amino acid residues 443-535 of menin made by using glutathione-S-transferase gene fusion.

RESULTS

Based on the results of RT-PCR and Western blot analysis, both MEN1 mRNA and menin protein appeared to be highly expressed in Cushing syndrome resulting from adrenocortical adenomas and carcinoma. However, their expression was found to be greatly decreased in primary aldosteronism compared with their expression in Cushing syndrome. Although weak expression of MEN1 mRNA also was detected in pheochromocytoma on RT-PCR, menin expression was not detected in any case of pheochromocytoma by Western blot analysis, possibly due to the lower sensitivity of this assay compared with RT-PCR. Neither MEN1 mRNA nor menin protein was detected in any of the corresponding adjacent tumor tissues examined.

CONCLUSIONS

The findings of the current study indicate that menin expression appears to be up-regulated in Cushing syndrome, suggesting that adrenocortical proliferation might be one of the primary lesions in the MEN1 syndrome in which menin might play a significant role in some specific cellular functions.

Isoforms of protein kinase C and their distribution in human adrenal cortex and tumors

The cytosol and microsomal fractions of human adrenal cortex contain 3 isoforms of protein kinase C: alpha, zeta, and epsilon. The latter fraction is present in trace amounts. No isoforms beta1, beta2, gamma and delta were found in these cell fractions. The distribution of alpha-isoform between the cytosol and microsomal fraction is determined by tissue origin: in normal tissue its content differs by no more than 10%, while in most tumors this isoform is translocated into the microsomal fraction. The distribution of zeta-isoform did not depend on tissue origin.

Immunocytochemical localization of NOVH protein and ultrastructural characteristics of NCI-H295R cells

In this study we present biochemical and immunocytochemical results on NOVH protein secretion and localization in NCI-H295R cells, as well as results on the ultrastructural characteristics of NCI-H295R cells. NCI-H295R cells were characterized by small quantities of rough and smooth endoplasmic reticulum, many free ribosomes, large nuclei with prominent nucleoli, numerous elongated mitochondria, a few Golgi complexes, and a small number of lipid droplets. Large numbers of coated pits and coated vesicles were present, but no secretory granules or exocytotic profiles were seen. Best ultrastructural preservation of NCI-H295R cells was achieved when fixation was done directly on the culture dishes and the cells were detached by scraping. Our biochemical results showed that NCI-H295R cells secreted large amounts of NOVH protein. The immunocytochemical localization of NOVH protein showed that the protein was localized in the cytoplasm, the plasma membrane and the nuclear envelope. This localization pattern, along with the ultrastructural and biochemical findings raise interesting questions on the function(s) and the mode of secretion of NOVH protein.

Angiotensin II type 1 receptor and ACTH receptor expression in human adrenocortical neoplasms

OBJECTIVE

Type 1 angiotensin II (Ang II) receptors transduce most of the known actions of Ang II, including steroidogenesis and trophic actions on the adrenal cortex. We investigated the type 1 Ang II receptor expression in adrenocortical tissues to define its regulation in adrenocortical neoplasms and to compare its expression with that of the ACTH receptor (ACTH-R).

PATIENTS AND MEASUREMENTS

Poly A RNA was extracted from tumour tissue and electrophoresed through a 1.0% agarose gel, blotted and hybridized with alpha32P-CTP labelled PCR generated type 1 Ang II receptor cDNA probe. Receptor autoradiography was performed on slices from normal adrenals and tumour tissue by incubation with 125I-Sar1, Ile8-Ang II with and without pretreatment with cold Ang II or with the selective type 1 receptor antagonist losartan.

RESULTS

Ang II type 1 receptor mRNA was high in cortisol producing (CPA; n = 5) and aldosterone producing (APA; n = 4) adenomas (normal adrenals 100 +/- 12% vs. 180 +/- 16% in CPA and 154 +/- 26% in APA, mean +/- SEM), but was low in nonfunctioning adenomas (NFA; n = 2; 2 +/- 1%). ACTH receptor mRNA followed a similar pattern (CPA 178 +/- 17, APA 196 +/- 30, NFA 0%, carcinomas 56 +/- 11%) with a good correlation between Ang II type 1 receptor and ACTH-R mRNA of r = 0.692, P = 0.0019. Receptor autoradiography in normal adrenals demonstrated Ang II type 1 receptors predominantly in the zona glomerulosa. In tumour tissue, mainly type 1 receptor expression was found confirming the Northern blot data.

CONCLUSIONS

Angiotensin II type 1 receptor and ACTH receptor expression seems to be correlated with the functional status of adrenocortical tumours, suggesting regulation by similar factors. The predominant receptor expressed in adrenocortical tumours is the Angiotensin II type 1 receptor whereas type 2 receptor expression is minimal.

Adrenocortical adenocarcinoma in an MSH2 carrier: coincidence or causal relation?

A woman is described who developed an ovarian adenocarcinoma, 3 metachronous colorectal adenocarcinomas, and a primary adrenocortical adenocarcinoma. Genetic investigation of the mismatch repair genes MLH1 and MSH2 showed a germline mutation in MSH2. Colorectal and ovarian carcinoma belong to the tumor spectrum of hereditary nonpolyposis colorectal cancer (HNPCC). Adrenocortical adenocarcinoma, however, has never been described as 1 of the HNPCC-associated tumors. To investigate whether the adrenocortical adenocarcinoma in this patient was caused by the MSH2 germline mutation, determination of microsatellite instability (MSI) and immunohistochemical analysis were performed on 1 of the colorectal tumors and the adrenocortical adenocarcinoma. MSI and general loss of MSH2 protein expression could be seen in the colorectal tumor but not in the adrenocortical adenocarcinoma. Therefore, it is highly unlikely that the adrenocortical adenocarcinoma found in this patient was due to her genetic predisposition for HNPCC. HUM PATHOL 31:1522-1527.

Anti-Müllerian hormone is a specific marker of sertoli- and granulosa-cell origin in gonadal tumors

Sex cord stromal tumors are gonadal neoplasms containing Sertoli, granulosa, Leydig, or thecal cells, which originate from cells derived from either the sex cords (Sertoli and granulosa cell tumors) or the specific mesenchymal stroma (Leydig and thecal cell tumors) of the embryonic gonad. Only granulosa and Sertoli cells produce anti-Müllerian hormone (AMH). Our purpose was to investigate whether AMH can be used as a specific marker of human granulosa or Sertoli cell origin in gonadal tumors, to distinguish them from other primary or metastatic neoplasms, using immunohistochemistry. We studied 7 juvenile and 6 adult-type granulosa cell tumors of ovarian localization and 3 extraovarian metastases, 20 other ovarian tumors, 6 testicular Sertoli cell tumors, 2 gonadoblastomas, and 13 extragonadal tumors. Granulosa cell tumors, both juvenile- and adult-type of either ovarian or metastatic localization, showed an heterogeneous pattern of AMH immunoreactivity: Areas containing intensely or weakly AMH-positive cells were intermingled with AMH-negative areas. Although in most cases AMH-positive areas represented a minor proportion of tumor cells, we found a positive reaction in all the cases examined. In testes, although normal prepubertal Sertoli cells were intensely positive, testicular Sertoli cell tumors showed large areas of negative reaction, with few positive cells scattered throughout the tumor. AMH was also reactive in most of the cells of sex-cord origin in gonadoblastomas. No AMH immunoreaction was observed in other gonadal and extragonadal tumors. We conclude that AMH expression is conserved in only a small proportion of tumor cells of granulosa or Sertoli cell origin; however, a positive reaction in a few cells helps to distinguish between granulosa or Sertoli cell tumors or gonadoblastomas and other gonadal tumors of different origin.

Expression of inhibin alpha in adrenocortical tumours reflects the hormonal status of the neoplasm

Inhibins are gonadal glycoprotein hormones whose main endocrine function is to inhibit pituitary FSH secretion. In addition to testes and ovaries, other steroid-producing organs are sites of inhibin alpha subunit expression. To study the role of inhibins in human adrenal gland, we screened a panel of 150 adrenals (10 normal adrenals, 25 adrenocortical hyperplasias, 65 adrenocortical adenomas, 30 adrenocortical carcinomas and 20 phaeochromocytomas) for inhibin alpha expression. mRNA levels of inhibin alpha subunit were studied in 57 samples and all tissues were stained immunohistochemically with an inhibin alpha subunit-specific antibody. Inhibin alpha mRNA was detected in all adrenocortical tissues. Virilizing adenomas possessed a 10-fold higher median inhibin alpha mRNA expression than did normal adrenals. Bilaterally and nodularly hyperplastic adrenals and other than virilizing adrenocortical tumours had their median inhibin alpha mRNA levels close to those of normal adrenals. Immunohistochemically, inhibin alpha subunit was detectable in all normal and hyperplastic adrenals, as well as in 73% of the adrenocortical tumours. However, the percentage of inhibin alpha-positive cells varied greatly in different tumour types. The median percentage of positive cells was 10 in non-functional and Conn's adenomas, 30 in Cushing's adenomas and 75 in virilizing adenomas. In malignant adrenocortical tumours the median percentage of inhibin alpha-immunopositive cells was 20 in non-functional carcinomas, 30 in Conn's carcinomas, 65 in Cushing's carcinomas and 75 in virilizing carcinomas. All phaeochromocytomas were negative for inhibin alpha subunit both at the mRNA level and immunohistochemically. Our data show that inhibin alpha subunit is highly expressed in both normal and neoplastic androgen-producing adrenocortical cells, with less expression in cortisol-producing and hardly any in aldosterone-producing cells. This suggests a specific role for inhibins in the regulation of adrenal androgen production. We did not find any significant difference in inhibin alpha expression between benign and malignant adrenocortical tumours. Thus inhibin alpha gene does not seem to have a tumour suppressor role in human adrenal cortex.

Expression of activin A and its receptors in human pheochromocytomas

Activin A (a homodimer of two activin betaA subunits) has been shown to induce the neuronal differentiation of rat pheochromocytoma PC12 cells. We studied activin A and its receptor gene expression in human pheochromocytomas in vivo and in vitro to clarify the potential involvement of activin A in the pathophysiology of these tumors. We first screened 20 pheochromocytomas and nine normal adrenal tissues for activin betaA mRNA expression. Northern blots hybridized with specific oligonucleotide probes detected weak signals for activin betaA transcripts in pheochromocytomas. Both type I and type II activin receptor (ActR-I, ActR-IB and ActR-II) mRNA expression was also detectable in the pheochromocytoma tissues. In primary cultures of pheochromocytoma cells, expression of activin betaA mRNA was readily detectable by Northern blotting, and secretion of activin A into the conditioned medium was confirmed by an enzyme-linked immunosorbent assay. The expression of activin betaA mRNA and secretion of activin A were induced by (Bu)(2)cAMP after 1 and 3 days of treatment (all P<0.05). A protein kinase inhibitor, staurosporine, inhibited the basal and (Bu)(2)cAMP-induced accumulation of activin betaA mRNA (P<0.05). In addition, induction of chromaffin phenotype by dexamethasone also inhibited the basal and (Bu)(2)cAMP-induced expression of activin A at both mRNA and protein levels (all P<0.05). In contrast, the expression of ActR-I and ActR-IB mRNAs was not affected by these agents in cultured pheochromocytoma cells. In summary, activin betaA subunit and activin receptors are expressed in human pheochromocytomas. Production of activin A in cultured pheochromocytoma cells is induced through the protein kinase A pathway, but reduced during chromaffin differentiation. Therefore, activin A may function as a local neurotrophic factor via an auto/paracrine manner in human pheochromocytomas.

Vascular endothelial growth factor and basic fibroblast growth factor evaluation in blood serum of patients with hormonally active and inactive adrenal gland tumours

The vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) levels of 36 patients with adrenal gland tumours were analysed. The mean age of patients was 43 years (29-67 years), and there were 25 women (69.4%) and 11 men (31.6%). In 34 patients adrenalectomy was performed and in two cases lesions were considered inoperable. In all cases VEGF and bFGF were measured preoperatively and in all operated patients the level of VEGF was measured at 1 month postoperatively. A statistically significant increase in VEGF levels before surgery in comparison with the controls was recorded in all patients with adrenal tumours. No correlation between the size of a tumour and VEGF levels was observed. The serum level of VEGF decreased in patients after surgical removal of the tumour, no matter which type of tumour, with the exception of a patient showing a recurrence of cortex cancer. A statistically significant decrease was found only in patients operated on for cortex cancers and hormonally active and inactive cortex and medulla inactive benign tumours. The postoperative recurrence of the malignant tumour may be preceded by an increase in plasma VEGF levels. Such correlations were not found with bFGF.

Diagnostic utility of the monoclonal antibody A103 in fine-needle aspiration biopsies of the adrenal

Fine-needle aspiration (FNA) of the adrenal is a useful modality for the evaluation of primary and metastatic neoplasms. Until now, however, few reliable markers existed for the positive identification of adrenal cortical cells. Originally studied as a melanoma marker, Melan-A, as detected by the murine monoclonal antibody, A103, has gained recent attention as a marker for steroid-producing cells. Formalin-fixed, paraffin-embedded cell blocks from 24 adrenal FNA specimens were stained for cytokeratins (AE1/AE3) and Melan-A (A103). Seven of 8 cases containing normal, hyperplastic, and neoplastic adrenal cortical cells were positive for A103. Among 16 cases of metastatic carcinoma, tumor cells in 14 samples were positive for cytokeratins but negative for A103. The A103 monoclonal antibody is a sensitive marker for the identification of normal, hyperplastic, and neoplastic adrenal cortical cells in cell blocks of adrenal FNA specimens. With the exception of melanoma, A103 reactivity is restricted to adrenal cortical and other steroid-producing cells. A103 should be used routinely for the evaluation of FNA specimens of adrenal mass lesions.

Utilization of microdissection and the polymerase chain reaction for the diagnosis of adrenal cortical carcinoma in fine-needle aspiration cytology

BACKGROUND

Loss of heterozygosity (LOH) for several tumor suppressor genes (including loci on 3p, 1p, and 17p,) has been documented in surgical specimens of adrenal cortical carcinomas (ACCA) without accompanying losses in benign hyperplastic and adenomatous adrenal cortical lesions (ACL). This disparate pattern of LOH raises the possibility of exploitation of these differences for diagnostic utilization. Cytologic differentiation of benign versus malignant ACL may be impossible based solely on fine-needle aspiration (FNA) material. The authors attempted to extrapolate the genetic findings on surgical specimens to FNA specimens of ACL to determine whether LOH studies could be utilized as a definitive diagnostic tool.

METHODS

Microdissection of archival material was performed on FNAs of ten ACCAs (stained with the Papanicolaou and Diff-Quik stains) with corresponding histologic material (stained with hematoxylin and eosin), one FNA of a benign ACL, and three touch preparations of benign adrenal cortex. LOH analysis was performed by polymerase chain reaction (PCR) with flanking markers for the following putative tumor suppressor genes: p53 (17p13; TP53), 1p (1p36; D1S165), and the von Hippel-Lindau gene at 3p25 (D3S1038 and D3S1110).

RESULTS

Similar results were obtained with cytologic and histologic material. As expected, benign ACL showed no LOH for the markers examined. Of the informative ACCA cases, 70% showed LOH for at least 1 of the 3 markers tested on both FNA and histologic samples. For all cases with amplifiable DNA, there was a 100% concordance rate for LOH between cytologic and histologic material, with at least 7 of the 10 cytologic samples originating from metastatic lesions and all of the surgical material originating from the primary adrenal neoplasm.

CONCLUSIONS

The results of this study suggest that the combination of microdissection and PCR for LOH of p53, 1p, and 3p25 from FNA material has the potential to be utilized to distinguish ACCA from benign ACL in informative cases. It also shows a 100% concordance rate between metastatic and primary ACCAs for the losses observed, a finding that can be extremely useful for the definitive identification of metastatic lesions. Archival cytologic preparations of ACCA are a reliable source of DNA for LOH studies. [See editorial counterpoint on pages 173-5 and reply to counterpoint on pages 176-7, this issue.] Cancer (Cancer Cytopathol)

Different immunohistochemical patterns of TGF-beta1 expression in benign and malignant adrenocortical tumours

OBJECTIVE

Transforming growth-factor beta1 (TGF-beta1) influences a number of specific functions of adrenocortical cells in several animal species. The aim of our study was to evaluate by immunohistochemical analysis the presence and distribution of TGF-beta1 in normal adrenal tissue and in different adrenal tumours.

PATIENTS

We analysed 8 functioning (5 adenomas and 3 carcinomas) and 15 non functioning (6 adenomas and 9 carcinomas) adrenal tumours and 6 normal adrenal glands.

RESULTS

In normal adrenal glands, the glomerulosa and the reticularis zones displayed diffuse cytoplasmic staining, while the fasciculata zone was almost completely negative. Functioning adenomas displayed cytoplasmic staining restricted to compact cells while in nonfunctioning adenomas, prevalently composed by clear cells, no staining was observed. Overall, adrenal carcinomas were characterized by the lack of cytoplasmic positivity and by sporadic positive cells around vessels both in functioning and in nonfunctioning tumours.

CONCLUSIONS

TGF-beta1 expression is associated with active steroid secretion in normal adrenal tissue, as well as in benign cortical adenomas, while this relationship is lost in primary adrenal malignancies. These data provide indirect evidence for a regulatory role played by TGF-beta1 on steroid secretory pathways.

Detection of Ob-receptor in human adrenal neoplasms and effect of leptin on adrenal cell proliferation

Leptin, a hormone mainly secreted from adipose tissue, communicates a metabolic signal to the adrenal gland. Ob-Receptor (Ob-R) expression was reported in rat, mice and human adrenal glands. This study intended to investigate possible differences in the Ob-R expression and distribution of Ob-R protein in human adrenal tumors as compared to normal adrenal tissue. Proliferative effects of leptin were analyzed in the human adrenocortical carcinoma cell line (NCI-H295). The full length Ob-R mRNA and the isoforms B219.1 and B219.3 could be demonstrated by RT-PCR in all adrenal tumors (n=8), the tumor cell line (NCI-H295) and normal tissue. In contrast the Ob-R isoform B219.2 was absent in the carcinoma cell line and in most of the adrenal tumors (n=5), whereas it was present in normal adrenals. The Ob-R protein could be demonstrated in benign and malignant adrenocortical tumors. Pheochromocytomas showed only a weak immunostaining with the human Ob-R antibody. Human leptin did not affect the proliferation or variability of adrenal tumor cells as demonstrated by [3H]-thymidine assay and WST-1 test. In conclusion, although functional leptin receptors are expressed in human adrenal tumors, leptin does not regulate tumor cell proliferation.

p53 protein and its messenger ribonucleic acid in human adrenal tumors

The role of p53 tumor suppressor gene in the pathomechanism of adrenal tumors was investigated by measuring p53 protein and its messenger ribonucleic acid (mRNA) in 12 normal human adrenals as well as in 56 adrenal tumors (7 aldosterone-producing adenomas, 5 adrenocortical adenomas causing Cushing's syndrome, 19 non-hyperfunctioning adrenocortical adenomas, 5 adrenocortical carcinomas, 12 pheochromocytomas, 3 myelolipomas, 4 ganglioneuromas and 1 hemangioma). The p53 protein concentration was significantly increased in aldosterone-producing adenomas (394+/-36 pg/mg cytosolic protein, mean+/-SE, vs 266+/-18 in normal human adrenals), whereas the concentration of this protein in Cushing's adenomas, non-hyperfunctioning adrenocortical adenomas, pheochromocytomas, and in all but one adrenocortical carcinomas was similar to that measured in normal human adrenal tissues. One adrenocortical carcinoma tissue showed very high p53 protein content (3000 pg/mg cytosolic protein). By contrast, myelolipomas (23+/-20) ganglioneuromas (43+/-15) and a hemangioma (11 pg/mg cytosolic protein) had very low p53 protein content. Northern blot analysis revealed the presence of p53 mRNA in each adrenal tissue examined with highest levels in aldosterone-producing and Cushing's adenomas. It is possible that the differences in p53 protein and/or mRNA contents reflect corresponding differences in the pathogenetic importance of p53 alterations in these types of adrenal tumors.

Functional adrenal cortical tumors in childhood: a study of ploidy, p53-protein and nucleolar organizer regions (AgNORs) as prognostic markers

Prognostic markers in pediatric adrenal cortical tumors are difficult to define. We determined the ploidy, immunostaining of p53-protein and number of nucleolar organizer regions (AgNORs) in 16 such tumors and related them to clinical outcome, tumor weight (TW) and histologic Weiss' criteria. Eleven females and 5 males aged 0.4 to 15.6 years were followed for 8.7 years; 10 presented Cushing's and 6 virilization syndrome. Diploid (n = 4, x TW = 269 g, range: 17-800 g) and near-diploid tumors (n = 3, x TW = 55 g, range: 20-85 g) had good outcome, Weiss' criteria were 0-7, and p53 reactivity was negative in all. Among the aneuploid tumors (n = 9, x TW = 298 g, range: 7-1000 g), 6 had good outcome, 2 presented metastasis and 1 was lost to follow-up; Weiss' criteria were 2-8 and p53 reactivity was positive in 3 tumors (2 of them of malignant evolution). AgNORs number was not different in cases of good or poor outcome (3.65 +/- 1.9 vs 2.83 +/- 1.1). Our findings indicate that diploid and near-diploid cases had always a good outcome regardless of tumor weight. In aneuploid cases, tumor weights < 100 g had good outcome, while those > 750 g had poor prognosis. Malignant tumors were aneuploid and had reactivity to p53-protein. Good outcome in aneuploid tumors < 100 g is probably due to early treatment. The expression of p53-protein appears as a promising marker of poor prognosis. Weiss' criteria and AgNORs were not useful in the present series.

Variable expression of the V1 vasopressin receptor modulates the phenotypic response of steroid-secreting adrenocortical tumors

We studied the putative role of the vasopressin receptors in the phenotypic response of steroid-secreting adrenocortical tumors. A retrospective analysis of a series of 26 adrenocortical tumors responsible for Cushing's syndrome (19 adenomas and 7 carcinomas) showed that vasopressin (10 IU, i.m., lysine vasopressin) induced an ACTH-independent cortisol response (arbitrarily defined as a cortisol rise above baseline of 30 ng/mL or more) in 7 cases (27%). In comparison, 68 of 90 patients with Cushing's disease (76%) had a positive cortisol response. We then prospectively examined the expression of vasopressin receptor genes in adrenocortical tumors of recently operated patients (20 adenomas and 19 adrenocortical carcinomas). We used highly sensitive and specific quantitative RT-PCR techniques for each of the newly characterized human vasopressin receptors: V1, V2, and V3. The V1 messenger ribonucleic acid (mRNA) was detected in normal adrenal cortex and in all tumors. Its level varied widely between 2.0 x 10(2) and 4.4 x 10(5) copies/0.1 microgram total RNA, and adenomas had significantly higher levels than carcinomas, although there was a large overlap. Among the 6 recently operated patients who had been subjected to the vasopressin test in vivo, the tumor V1 mRNA levels were higher in the 4 responders (9.5 x 10(3) to 5.0 x 10(4)) than in the 2 nonresponders (2.0 x 10(2) and 1.8 x 10(3)). One adenoma that had a brisk cortisol response in vivo, also had in vitro cortisol responses that were inhibited by a specific V1 antagonist. In situ hybridization showed the presence of V1 mRNA in the normal human adrenal cortex where the signal predominated in the compact cells of the zona reticularis. A positive signal was also present in the tumors with high RT-PCR V1 mRNA levels; its distribution pattern was heterogeneous and showed preferential association with compact cells. RT-PCR studies for the other vasopressin receptors showed a much lower signal for V2 and no evidence for V3 mRNA. We could not establish whether the V2 mRNA signal observed in normal and tumoral specimens was present within adrenocortical cells or merely within tissue vessels. We conclude that the vasopressin V1 receptor gene is expressed in normal and tumoral adrenocortical cells. High, and not ectopic, expression occurs in a minority of tumors that become directly responsive to vasopressin stimulation tests.

The alpha subunit of inhibin in adrenal cortical neoplasia

We analyzed 23 adrenal adenomas and 15 adrenal cortical carcinomas by immunolabeling for the alpha subunit of inhibin, and we then compared the results with the functional status of the neoplasms. We also studied 19 pheochromocytomas, 30 renal cell carcinomas, and 5 extra-adrenal paragangliomas, tumors posing differential diagnostic problems with adrenal cortical neoplasms. Immunolabeling was performed using automated immunohistochemical methods and an antibody directed against the alpha subunit. Tumors were semiquantitatively assessed for the number of positive cells. Immunopositivity was obtained in 18 (78%) of 23 adrenal cortical adenomas, 12 (80%) of 15 adrenal cortical carcinomas, 2 (11%) of 19 pheochromocytomas, 0 of 5 extra-adrenal paragangliomas, and 0 of 30 renal cell carcinomas. Immunoreactivity was strong in 7 (78%) of 9 adrenal cortical tumors from patients with Cushing's-related or virilizing symptoms. In contrast, only 4 (14%) of 29 tumors that were clinically nonfunctioning or associated with hyperaldosteronism demonstrated strong staining (P < .001). In clinically nonfunctioning tumors, there was a tendency for increased immunopositivity in tumors from patients with elevated levels of cortisol, androgen, or their precursors, with four of six tumors having at least moderate immunopositivity. Similar reactivity was present in only one of eight tumors from patients with normal laboratory values (P=.091). Moderate or strong immunopositivity was present in 9 (60%) of 15 adrenal cortical carcinomas, whereas of the pheochromocytomas, extra-adrenal paragangliomas, and renal cell carcinomas, only 1 (1.9%) of 54 showed moderate-to-strong reactivity. We conclude that moderate or strong immunoreactivity for the alpha subunit of inhibin occurs in adrenal cortical tumors from patients with Cushing's-related or virilizing symptoms. Immunolabeling for the inhibin alpha subunit is potentially useful in the differential diagnosis of neoplasms that include adrenal cortical carcinomas.

Oncocytic adrenocortical neoplasms: a report of seven cases and review of the literature

Oncocytic neoplasms of the adrenal gland are rare. We describe the clinicopathologic and immunohistochemical findings of seven oncocytic adrenocortical neoplasms, five oncocytomas, and two oncocytic neoplasms of uncertain malignant potential. Three tumors were studied using electron microscopy. These neoplasms occurred in five women and two men (median age, 55 years) with no clinical evidence that the neoplasms were functional. The size of the neoplasms varied from 5.0 cm to 13.5 cm. Histologically, each neoplasm was composed exclusively of oncocytes. The oncocytomas had very low or absent mitotic activity and no evidence of necrosis. The two oncocytic neoplasms of uncertain malignant potential had increased mitotic activity and necrosis but no evidence of invasion or metastases. Nuclear atypia, either focal or generalized, was found in all neoplasms. Immunohistochemical studies performed using fixed, paraffin-embedded sections showed strong reactivity with the mitochondrial antibody mES-13 in all neoplasms. Four of five oncocytomas and one oncocytic neoplasm of uncertain malignant potential expressed keratin, predominantly keratin 18, as shown using the CAM 5.2 and AE3 antibodies. Two neuroendocrine-associated markers, neuron specific enolase and synaptophysin, were positive in seven and five neoplasms, respectively. However, all neoplasms were negative for the other neuroendocrine markers tested, including chromogranin A, tyrosine hydroxylase, and dopamine beta-hydroxylase, as well as for epithelial membrane antigen, S100, and p53. Using the MIB-1 (Ki-67) antibody, proliferative activity was increased in both oncocytic neoplasms of uncertain malignant potential. All six patients with available clinical follow-up data are alive without evidence disease, although the follow-up interval is relatively short (< 2 years) for the two patients with oncocytic neoplasms of uncertain malignant potential. We conclude that oncocytic adrenocortical neoplasms are nonfunctional tumors that can become large before they are detected by radiologic studies. The majority of neoplasms are benign and should not be misdiagnosed as carcinoma.

Increased levels of insulin-like growth factor II (IGF-II) and IGF-binding protein-2 are associated with malignancy in sporadic adrenocortical tumors

In adrenocortical tumors, malignancy is strongly associated with insulin-like growth factor II (IGF-II) gene overexpression and abnormalities at the 11p15 locus, suggesting a role for this growth factor in adrenocortical tumorigenesis. To further investigate this role, the IGF/IGF-binding protein (IGFBP) system was analyzed in 18 adrenocortical tumors, classified into 2 groups on the basis of their IGF-II messenger ribonucleic acid (mRNA) content (group 1, normal IGF-II mRNA content, mostly benign tumors; group 2, high IGF-II mRNA content, mostly malignant tumors). Group 2 tumors contained 10 times more IGF-II protein than group 1 tumors or normal adrenal tissue (P < 0.001), indicating efficient translation of IGF-II mRNA in malignant tumors. Western ligand blotting detected various functional IGFBPs in normal adrenocortical glands and tumors: a doublet of 39-42 kDa identified by immunoblotting as IGFBP-3, a band at 32 kDa, and bands at 29-30 and 24 kDa. Total IGFBP-3 protein levels were similar in the two groups of tumors. By contrast, malignant tumors differed from benign ones by specific expression of the 32-kDa IGFBP. Immunoblotting identified this 32-kDa band together with a proteolytic fragment of 25 kDa as IGFBP-2, and quantitative analysis showed significantly higher levels of total IGFBP-2 in malignant tumors than in benign tumors (P < 0.001). Despite enhanced levels of IGBP-2 protein in malignant tumors, no increase in IGFBP-2 mRNA levels was detected, suggesting post-transcriptional regulation of this IGFBP. These results confirm the major role of IGF-II in adrenocortical tumorigenesis and suggest that IGFBP-2 may be a regulator of IGF-II proliferative effects in this tumor system.

An approach to handling pediatric thyroid and adrenal tumors excluding neuroblastoma

Thyroid and adrenal tumors, excluding neuroblastoma, are infrequent in children. Because of the problems involved in applying diagnostic and prognostic criteria developed for adult tumors to pediatric tumors, proper diagnosis of thyroid and adrenal tumors in pediatric patients and proper patient management require close collaboration on the part of clinicians, surgeons, and surgical pathologists. In view of that fact, an approach to handling thyroid and adrenal tumors is presented. Special attention is paid to the following aspects of managing both types of tumors: procedure, fine-needle aspiration, intraoperative consultation (frozen sections), gross examination, histologic examination, special studies, diagnosis, and prognostic features.

Vascularity in human adrenal cortex

It has long been postulated that angiogenesis plays important roles in tumor cell proliferation and hormonal secretion of endocrine tumors, including adrenocortical neoplasms. Detailed examination of vascularity, however, has not been reported in adrenocortical tumors. In this study, we quantitatively examined vascularity in normal adrenal, adrenocortical adenoma, and carcinoma using an image analysis system to evaluate vascularity or angiogenesis in these lesions. Vascular density (VD: vessel number/mm2), endothelial area of each vessel (EA: microm2/vessel) and vascular area (VA: the percentage of EA per field) were examined using immunohistochemical analysis of CD34 and the CAS 200 image analysis system. EA and VA of adrenocortical carcinomas (EA, 113.4 +/- 33.1; VA, 6.34 +/- 2.03) were significantly higher than those of adenoma (EA, 66.1 +/- 43.0; VA, 3.11 +/- 1.56) and normal adrenal tissue (EA, 65.4 +/- 26.0; VA, 4.26 +/- 1.19). There were no significant differences in VD among normal cases (702.2 +/- 173.2), adenomas (488.9 +/- 153.2), and carcinomas (573.2 +/- 185.2). These results suggest that adrenocortical carcinoma might be associated with increased endothelial cell proliferation but not with an increased number of intratumoral microvessels. There were no significant differences in these parameters of vascularity examined in the zona glomerulosa, zona fasciculata, and zona reticularis of aldosteronomas, Cushing's adenomas, and nonfunctioning hormonally inactive adenomas nor between specimens from patients who died of the disease and those from patients who did not.

Localization and expression of adrenocorticotropic hormone receptor mRNA in normal and neoplastic human adrenal cortex

The recent cloning of the ACTH receptor (ACTH-R) gene allows investigation of the tissue localization and relative abundance of ACTH-R mRNA in normal and neoplastic adrenal cortex. Using in situ hybridization (ISH) we studied the expression of ACTH-R mRNA in four adult adrenals of brain-dead patients, two cortisol-producing adenomas (CPA), three aldosterone-producing adenomas (APA), one non-functional adenoma (NFA), and three carcinomas. The results were compared with the mRNA expression of key steroidogenic enzymes and of the glucocorticoid receptor (GR) mRNA using Northern blotting. In adult adrenals, messenger RNA encoding ACTH-R was localized in all three zones of the adrenal cortex, in accordance with the stimulatory role of ACTH on mineralocorticoid, glucocorticoid and adrenal androgen secretion. In comparison, expression of side-chain cleavage enzyme (P450scc) showed a similar tissue distribution with mRNA abundance in all three zones, whereas 17-hydroxylase/17-20 lyase (P450c17) mRNA expression was only detected in the zona fasciculata and zona reticularis. All CPAs and APAs expressed significant levels of ACTH-R mRNA whereas an NFA showed low expression of ACTH-R mRNA. Two of three adrenocortical carcinomas expressed ACTH-R mRNA. Northern analysis using dot blot was employed to quantify ACTH-R and GR mRNA expression and confirmed the ISH data: ACTH-R mRNA expression was high in CPAs (275 and 195% vs 100 +/- 25% in adult adrenals), APAs (127, 200 and 221%) and two carcinomas (99 and 132%), but low in the NFA (7%) and in an androgen secreting carcinoma (16%). GR mRNA expression was high in the NFA (195%) and in two of three carcinomas (93, 188, 227%). We conclude that ACTH-R mRNA is upregulated in functional adenomas by yet unidentified mechanisms. The tissue distribution of ACTH-R and P450 enzyme mRNA expression is highly variable in neoplastic adrenals and does not allow a clear differentiation between benign and malignant tumors.

Immunohistochemical staining of normal, hyperplastic, and neoplastic adrenal cortex with a monoclonal antibody against alpha inhibin

AIMS

To investigate the immunohisto-chemical staining of normal, hyperplastic, and neoplastic adrenal cortex with a monoclonal antibody against alpha inhibin. Also, to determine whether immunostaining with this antibody is useful in differentiating between adrenal cortical neoplasms and other tumours involving the adrenal gland that might mimic them.

METHODS

Normal adrenal tissue (n = 20) and specimens from cases of adrenal hyperplasia (n = 13), adrenal cortical adenoma (n = 15), adrenal cortical carcinoma (n = 4), phaeochromocytoma (n = 8), and adrenal metastatic tumour (n = 7) were stained with a monoclonal antibody against the alpha subunit of human inhibin.

RESULTS

Positive staining with the anti-alpha inhibin monoclonal antibody was seen in all normal adrenal glands. Immunoreactivity was largely confined to the inner cell layers of the adrenal cortex, with no staining of the adrenal medulla. All hyperplastic adrenal glands and adrenal cortical adenomas and carcinomas were also immunoreactive. The other tumours studied were negative.

CONCLUSIONS

There is consistent immunoreactivity with the anti-alpha inhibin monoclonal antibody in normal adrenal cortex and in hyperplastic and neoplastic adrenal cortical lesions. In the normal adrenal cortex, positive staining is mainly confined to the zona reticularis. Other neoplasms involving the adrenal gland are negative. Immunohistochemical staining with anti-alpha inhibin monoclonal antibody, performed as part of a panel, may prove to be of value in the distinction between adrenal cortical carcinoma and phaeochromocytoma or metastatic tumour.

Immunohistochemical study of cytochrome b5 in human adrenal gland and in adrenocortical adenomas from patients with Cushing's syndrome

Cytochrome b5, a component of the electron transfer system increases the relative activity of 17,20-lyase to 17alpha-hydroxylase of P450c17 in vitro. In the present study, immunohistochemical analysis of cytochrome b5 was performed in the human adrenal gland and in adrenocortical adenomas from patients with Cushing's syndrome. In the human adrenal gland, cytochrome b5 was stained in all three adrenocortical layers but the staining was most remarkable in the zona reticularis. All of the adenomas were composed mainly of compact cells, which exhibited immunoreactive staining for cytochrome b5 as well as for P450c17 and 3beta-hydroxysteroid dehydrogenase (3beta-HSD). The distribution of b5 in the adenomas was correlated with that of P450c17 rather than with that of 3beta-HSD. The immunoreactive staining for cytochrome b5 appeared to be more prominent in the two adenomas that produced relatively high concentrations of adrenal androgens than in adenomas that produced low concentrations of adrenal androgens. These results immunohistochemically support the functional association of b5 with androgen production through interaction with P450c17 and the previous finding that higher concentrations of cytochrome b5 are associated with greater production of adrenal androgens in adrenocortical adenomas from patients with Cushing's syndrome.

Expression of adrenomedullin mRNA in adrenocortical tumors and secretion of adrenomedullin by cultured adrenocortical carcinoma cells

Immunoreactive-adrenomedullin concentrations and the expression of adrenomedullin mRNA were studied in the tumor tissues of adrenocortical tumors. Northern blot analysis showed the expression of adrenomedullin mRNA in tumor tissues of adrenocortical tumors, including aldosterone-producing adenomas, cortisol-producing adenomas, a non-functioning adenoma and adrenocortical carcinomas, as well as normal parts of adrenal glands and pheochromocytomas. On the other hand, immunoreactive-adrenomedullin was not detected in about 90% cases of adrenocortical tumors (<0.12 pmol/g wet weight (ww)). Immunoreactive-adrenomedullin concentrations ranged from 0.44 to 198.2 pmol/g ww in tumor tissues of pheochromocytomas and were 9.2 +/- 1.2 pmol/g ww (mean +/- SD, n = 4) in normal parts of adrenal glands. Adrenomedullin mRNA was expressed in an adrenocortical adenocarcinoma cell line, SW-13 and immunoreactive-adrenomedullin was detected in the culture medium of SW-13 (48.9 +/- 1.8 fmol/10(5) cells/24h, mean +/- SEM, n = 4). On the other hand, immunoreactive-adrenomedullin was not detectable in the extract of SW-13 cells (<0.09 fmol/10(5) cells), suggesting that adrenomedullin was actively secreted from SW-13 cells without long-term storage. These findings indicate that adrenomedullin is produced and secreted, not only by pheochromocytomas, but also by adrenocortical tumors. Undetectable or low levels of immunoreactive-adrenomedullin in the tumor tissues of adrenocortical tumors may be due to very rapid secretion of this peptide soon after the translation from these tumors.

Adrenocorticotropic hormone regulates the activities of the orphan nuclear receptor Nur77 through modulation of phosphorylation

ACTH treatment of Y1 adrenocortical cells induces the synthesis of Nur77, an orphan nuclear receptor that can act as a potent transactivator for such genes as 21-hydroxylase (CYP21). Nur77 has thus been proposed to be a mediator of ACTH action in activating the expression of genes that encode steroidogenic enzymes. Here we show that ACTH regulates the activity of Nur77 at the level of phosphorylation. ACTH induces the synthesis of transcriptionally active, DNA-binding Nur77 that is unphosphorylated at Ser354, which resides within the DNA-binding domain. By contrast, the Nur77 population that is constitutively present in Y1 cells is phosphorylated at Ser354 and does not bind DNA. Substitutions of Ser354 with negatively charged amino acids, such as Asp or Glu, dramatically decreased Nur77 DNA-binding and trans-activation activities, whereas mutation to the neutral Ala had no effect. Aside from phosphorylation within the DNA-binding domain, ACTH treatment does not induce modifications in the N- and C-terminal domains of Nur77 that significantly affect activity. Although the specific kinases that phosphorylate Nur77 in vivo are not known, the mitogen-activated protein kinase/pp90RSK pathway is not critical to Nur77 regulation. We propose that ACTH treatment of Y1 cells results in modulation of the activities of both kinases and phosphatases, which, in turn, regulate the activities of such transcription factors as Nur77.