International initiative for a curated SDHB variant database improving the diagnosis of hereditary paraganglioma and pheochromocytoma.

BACKGROUND: SDHB is one of the major genes predisposing to paraganglioma/pheochromocytoma (PPGL). Identifying pathogenic SDHB variants in patients with PPGL is essential to the management of patients and relatives due to the increased risk of recurrences, metastases and the emergence of non-PPGL tumours. In this context, the 'NGS and PPGL (NGSnPPGL) Study Group' initiated an international effort to collect, annotate and classify SDHB variants and to provide an accurate, expert-curated and freely available SDHB variant database. METHODS: A total of 223 distinct SDHB variants from 737 patients were collected worldwide. Using multiple criteria, each variant was first classified according to a 5-tier grouping based on American College of Medical Genetics and NGSnPPGL standardised recommendations and was then manually reviewed by a panel of experts in the field. RESULTS: This multistep process resulted in 23 benign/likely benign, 149 pathogenic/likely pathogenic variants and 51 variants of unknown significance (VUS). Expert curation reduced by half the number of variants initially classified as VUS. Variant classifications are publicly accessible via the Leiden Open Variation Database system (https://databases.lovd.nl/shared/genes/SDHB). CONCLUSION: This international initiative by a panel of experts allowed us to establish a consensus classification for 223 SDHB variants that should be used as a routine tool by geneticists in charge of PPGL laboratory diagnosis. This accurate classification of SDHB genetic variants will help to clarify the diagnosis of hereditary PPGL and to improve the clinical care of patients and relatives with PPGL.

Hemodynamic parameters in patients undergoing surgery for pheochromocytoma/paraganglioma: a retrospective study.

BACKGROUND: Pheochromocytoma (PHEO) and paraganglioma (PGL) are rare neuroendocrine tumors characterized by hemodynamic instability, caused by the paroxysmal release of catecholamines. Patients may develop cardiovascular complications in the perioperative phase due to the massive release of catecholamines, particularly during anesthetic induction and surgical manipulation of the tumor. The aim of this retrospective study was to evaluate the risk factors involved in perioperative hemodynamic instability in patients who underwent surgery for chromaffin tumors. METHODS: Forty patients (median age 55 [36.50-64.50]) undergone surgery for PHEO/abdominal PGL from January 2011 to December 2016 at the AOU Careggi (Florence, Italy) were retrospectively evaluated. Systolic, diastolic, and mean blood pressure were considered at baseline and during surgery. Patients with blood pressure steadily < 140/90 mmHg before surgery were considered "adequately prepared". A preoperative therapy with doxazosin, a selective alpha-1 blocker, was started in all patients for at least 14 days prior to the surgery. The presence of hemodynamic instability was reported. RESULTS: Comparing males and females, a significant difference in doxazosin daily dose (p = 0.018), systolic blood pressure (p = 0.048), and in the proportion of adequately prepared patients (p = 0.031) emerged. A positive correlation between preoperative daily dose of doxazosin, tumor size (B = 0.60, p < 0.001), and urinary normetanephrine levels (B = 0.64, p < 0.001) was also observed. Hemodynamic instability occurred in 30.0% of patients. The absence of adequate preparation (p = 0.012) before surgery, urinary normetanephrine levels (NMNur p = 0.039), and surgery time (minutes) (p = 0.021) resulted as risk factors of hemodynamic instability in our series. The use of intraoperative drugs was higher in patients with hemodynamic instability (p < 0.001). A pre-surgical SBP level of > 133 mmHg (OR = 6 CI95% 1.37-26.20, p = 0.017) and an intraoperative SBP and MBP levels of > 127 mmHg (OR = 28.80 CI95% 2.23-371.0, p = 0.010) and > 90 mmHg (OR = 18.90 CI95% 1.82-196.0, p = 0.014), respectively, were identified as effective thresholds to recognize patients at higher risk of HI. CONCLUSIONS: A preoperative therapy with alpha-blockers is useful, but not sufficient to avoid surgical risks. Patients with higher pre-surgical levels of NMNur, pre-surgical SBP > 133 mmHg, and/or intraoperative SBP > 127 mmHg and MBP > 90 mmHg, should be carefully monitored. A multidisciplinary approach is indispensable to optimize the management of PHEOs/abdominal PGLs in order to reduce surgical complications.

Novel Germline PHD2 Variant in a Metastatic Pheochromocytoma and Chronic Myeloid Leukemia, but in the Absence of Polycythemia.

Background: Pheochromocytoma (Pheo) and paraganglioma (PGL) are rare tumors, mostly resulting from pathogenic variants of predisposing genes, with a genetic contribution that now stands at around 70%. Germline variants account for approximately 40%, while the remaining 30% is attributable to somatic variants. Objective: This study aimed to describe a new PHD2 (EGLN1) variant in a patient affected by metastatic Pheo and chronic myeloid leukemia (CML) without polycythemia and to emphasize the need to adopt a comprehensive next-generation sequencing (NGS) panel. Methods: Genetic analysis was carried out by NGS. This analysis was initially performed using a panel of genes known for tumor predisposition (EGLN1, EPAS1, FH, KIF1Bß, MAX, NF1, RET, SDHA, SDHAF2, SDHB, SDHC, SDHD, TMEM127, and VHL), followed initially by SNP-CGH array, to exclude the presence of the pathogenic Copy Number Variants (CNVs) and the loss of heterozygosity (LOH) and subsequently by whole exome sequencing (WES) comparative sequence analysis of the DNA extracted from tumor fragments and peripheral blood. Results: We found a novel germline PHD2 (EGLN1) gene variant, c.153G>A, p.W51*, in a patient affected by metastatic Pheo and chronic myeloid leukemia (CML) in the absence of polycythemia. Conclusions: According to the latest guidelines, it is mandatory to perform genetic analysis in all Pheo/PGL cases regardless of phenotype. In patients with metastatic disease and no evidence of polycythemia, we propose testing for PHD2 (EGLN1) gene variants. A possible correlation between PHD2 (EGLN1) pathogenic variants and CML clinical course should be considered.

Outcome and genetic analysis of patients affected by retinal capillary hemangioblastoma in von Hippel Lindau syndrome.

Purpose: To describe genetic analysis, treatment results, and complications of patients affected by retinal capillary hemangioblastoma (RCH) in von Hippel Lindau (VHL) syndrome. Methods: We collected 17 patients with VHL syndrome, who underwent a molecular test and an ophthalmic evaluation at the Eye Clinic of the University Hospital of Florence from January 2005 to February 2020. We focused on eyes showing RCHs examined using color fundus photographs, fluorescein angiography, and optical coherence tomography. Results: Eight eyes of six patients (6/17; 35%) showed RCHs at the fundoscopic examination. All RCHs were treated with laser therapy. Three eyes underwent episcleral surgery, one eye showing vitreous hemorrhage received three intravitreal (IV) anti-VEGF injections and three cryotherapy procedures, and one eye underwent vitrectomy. In patients with RCHs, five were characterized by a truncating mutation of the VHL protein, and one patient showed a missense mutation. We have reported two VHL mutations not reported in literature. Conclusions: Patients with multiple RCHs, who developed RCH secondary effects, showed truncating mutations of the VHL protein. We recommend early screening and close monitoring, especially if RCHs are detected at presentation, for every patient with VHL syndrome independently of the results of the molecular test for a missense or a truncating mutation in VHL.

SDHx and Non-Chromaffin Tumors: A Mediastinal Germ Cell Tumor Occurring in a Young Man with Germline SDHB Mutation.

Background: Mutations in genes encoding one of the subunits of succinate dehydrogenase (SDH) are involved in pheochromocytoma (PHEO) and paraganglioma (PGL) development. Over the last few years, such mutations have also been associated with non-chromaffin tumors. However, immunohistochemistry (IHC) on the tumor tissue and a study on the loss of heterozygosity (LOH) aimed at demonstrating the pathogenic role of SDHx genes have only been employed in a few cases. Case report: We describe the case of a 19-year-old Caucasian man with a germline SDHB mutation, who presented with acne vulgaris resistant to medical treatment. His follow-up for chromaffin tumors was negative, while hormonal tests revealed suppressed gonadotropins with testosterone in the upper range of normality and elevated ß-human chorionic gonadotropin (ß-hCG). At the whole-body enhanced CT scan, a mediastinal lesion suggestive of a germ cell tumor (GCT) was detected. 18FDG-PET (fluorodeoxyglucose-positron emission tomography) imaging showed low glucose metabolism at the mediastinal site. Surgical removal of the mass was uneventful. Pathology confirmed the diagnosis of GCT consisting of cystic teratoma (95%) and seminoma (5%). IHC for SDHB showed normal protein expression, and genetic analysis of the tumor tissue revealed the absence of SDHB LOH. Normalization of the hormonal tests and acne attenuation were achieved after surgery. Conclusion: We report an incidental association of a germinal SDHB mutation and mediastinal GCT in a young Caucasian man. Our paper highlights the importance of IHC and genetic analysis in confirming the etiologic role of SDHx genes in nonchromaffin tumors, thus excluding incidental associations.

Metabolome-guided genomics to identify pathogenic variants in isocitrate dehydrogenase, fumarate hydratase, and succinate dehydrogenase genes in pheochromocytoma and paraganglioma.

PURPOSE: Metabolic aberrations have been described in neoplasms with pathogenic variants (PV) in the Krebs cycle genes encoding succinate dehydrogenase (SDH), fumarate hydratase (FH) and isocitrate dehydrogenase (IDH). In turn, accumulation of oncometabolites succinate, fumarate, and 2-hydroxyglutarate can be employed to identify tumors with those PV . Additionally, such metabolic readouts may aid in genetic variant interpretation and improve diagnostics. METHODS: Using liquid chromatography-mass spectrometry, 395 pheochromocytomas and paragangliomas (PPGLs) from 391 patients were screened for metabolites to indicate Krebs cycle aberrations. Multigene panel sequencing was applied to detect driver PV in cases with indicative metabolite profiles but undetermined genetic drivers. RESULTS: Aberrant Krebs cycle metabolomes identified rare cases of PPGLs with germline PV in FH and somatic PV in IDHx and SDHx, including the first case of a somatic IDH2 PV in PPGL. Metabolomics also reliably identified PPGLs with SDHx loss-of-function (LOF) PV. Therefore we utilized tumor metabolite profiles to further classify variants of unknown significance in SDHx, thereby enabling missense variants associated with SDHx LOF to be distinguished from benign variants. CONCLUSION: We propose incorporation of metabolome data into the diagnostics algorithm in PPGLs to guide genetic testing and variant interpretation and to help identify rare cases with PV in FH and IDHx.

Yeast model for evaluating the pathogenic significance of SDHB, SDHC and SDHD mutations in PHEO-PGL syndrome.

SDH genes, encoding succinate dehydrogenase, act as tumour suppressor genes, linking mitochondrial dysfunction with tumourigenesis. Heterozygous germline mutations in SDHA, SDHB, SDHC, SDHD and in the assembly factor encoding gene SDHAF2 have all been shown to predispose to heritable endocrine neoplasias such as pheochromocytomas (PHEO) and paragangliomas (PGLs) called 'PHEO-PGL syndrome'. SDH genes mutations, in addition to deletions or truncations which are most likely pathogenic, often include missense substitutions which can be of uncertain significance. Unclassified missense substitutions may be difficult to interpret unless the cause-effect link between mutation and the disease is established by functional and in silico studies or by the familial segregation with the phenotype. Using the yeast model, here, we report functional investigations on several missense SDH mutations found in patients affected by pheochromocytomas or paragangliomas. The aim of this study was to evaluate whether and to which extent the yeast model may be useful for establishing the pathological significance of missense SDH mutations in humans. The results of our study demonstrate that the yeast is a good functional model to validate the pathogenic significance of SDHB missense mutations while, for missense mutations in SDHC and SDHD genes, the model can be informative only when the variation involves a conserved residue in a conserved domain.

Tumoral EPAS1 (HIF2A) mutations explain sporadic pheochromocytoma and paraganglioma in the absence of erythrocytosis.

Pheochromocytomas (PCCs) and paragangliomas (PGLs) are chromaffin-cell tumors that arise from the adrenal medulla and extra-adrenal paraganglia, respectively. The dysfunction of genes involved in the cellular response to hypoxia, such as VHL, EGL nine homolog 1, and the succinate dehydrogenase (SDH) genes, leads to a direct abrogation of hypoxia inducible factor (HIF) degradation, resulting in a pseudo-hypoxic state implicated in PCC/PGL development. Recently, somatic post-zygotic mutations in EPAS1 (HIF2A) have been found in patients with multiple PGLs and congenital erythrocytosis. We assessed 41 PCCs/PGLs for mutations in EPAS1 and herein describe the clinical, molecular and genetic characteristics of the 7 patients found to carry somatic EPAS1 mutations; 4 presented with multiple PGLs (3 of them also had congenital erythrocytosis), whereas 3 were single sporadic PCC/PGL cases. Gene expression analysis of EPAS1-mutated tumors revealed similar mRNA EPAS1 levels to those found in SDH-gene- and VHL-mutated cases and a significant up-regulation of two hypoxia-induced genes (PCSK6 and GNA14). Interestingly, single nucleotide polymorphism array analysis revealed an exclusive gain of chromosome 2p in three EPAS1-mutated tumors. Furthermore, multiplex-PCR screening for small rearrangements detected a specific EPAS1 gain in another EPAS1-mutated tumor and in three non-EPAS1-mutated cases. The finding that EPAS1 is involved in the sporadic presentation of the disease not only increases the percentage of PCCs/PGLs with known driver mutations, but also highlights the relevance of studying other hypoxia-related genes in apparently sporadic tumors. Finally, the detection of a specific copy number alteration affecting chromosome 2p in EPAS1-mutated tumors may guide the genetic diagnosis of patients with this disease.

Targeted NGS Molecular Profiling and Its Clinical Application in Adrenocortical Cancer.

OBJECTIVE: Adrenal cortical carcinoma (ACC) is a rare malignancy with a generally poor but heterogeneous prognosis, especially depending on the tumour stage at diagnosis. Identification of somatic gene alterations combined with clinical/histopathological evaluation of the tumour can help improve prognostication. We applied a simplified targeted-NGS panel to characterise the mutational profiles of ACCs, providing potentially relevant information for better patient management. DESIGN AND METHODS: Thirty frozen tumour specimens from a local ACC series were retrospectively analysed by a custom-NGS panel (CDKN2A, CTNNB1, DAXX, MED12, NF1, PRKAR1A, RB1, TERT, TP53, ZNRF3) to detect somatic prioritized single-nucleotide variants. This cohort was integrated with 86 patients from the ACC-TCGA series bearing point-mutations in the same genes and their combinations identified by our panel. Primary endpoints of the analysis on the total cohort (113 patients) were overall (OS) and progression-free (PFS) survival, and hazard-ratio (HR) for the different alterations grouped by the signalling pathways/combinations affected. RESULTS: Different PFS, OS and HR were associated to the different pathways/combinations, being NF1 + TP53 and Wnt/ß-catenin + Rb/p53 combined mutations the most deleterious, with a statistical significance for progression HR which is retained only in low-(I/II) stages - NF1+TP53 combination: HR = 2.96[1.01-8.69] and HR = 13.23[3.15-55.61], all and low stages, respectively; Wnt/ß-catenin + Rb/p53 combined pathways: HR = 6.47[2.54-16.49] and HR = 16.24[3.87-68.00], all and low-stages, respectively. CONCLUSIONS: A simplified targeted-NGS approach seems the best routinely applicable first step towards somatic genetic characterisation of ACC for prognostic assessment. This approach proved to be particularly promising in low-stage cases, suggesting the need for more stringent surveillance and personalised treatment.

Pheochromocytoma in rats with multiple endocrine neoplasia (MENX) shares gene expression patterns with human pheochromocytoma.

Pheochromocytomas are rare neoplasias of neural crest origin arising from chromaffin cells of the adrenal medulla and sympathetic ganglia (extra-adrenal pheochromocytoma). Pheochromocytoma that develop in rats homozygous for a loss-of-function mutation in p27Kip1 (MENX syndrome) show a clear progression from hyperplasia to tumor, offering the possibility to gain insight into tumor pathobiology. We compared the gene-expression signatures of both adrenomedullary hyperplasia and pheochromocytoma with normal rat adrenal medulla. Hyperplasia and tumor show very similar transcriptome profiles, indicating early determination of the tumorigenic signature. Overrepresentation of developmentally regulated neural genes was a feature of the rat lesions. Quantitative RT-PCR validated the up-regulation of 11 genes, including some involved in neural development: Cdkn2a, Cdkn2c, Neurod1, Gal, Bmp7, and Phox2a. Overexpression of these genes precedes histological changes in affected adrenal glands. Their presence at early stages of tumorigenesis indicates they are not acquired during progression and may be a result of the lack of functional p27Kip1. Adrenal and extra-adrenal pheochromocytoma development clearly follows diverged molecular pathways in MENX rats. To correlate these findings to human pheochromocytoma, we studied nine genes overexpressed in the rat lesions in 46 sporadic and familial human pheochromocytomas. The expression of GAL, DGKH, BMP7, PHOX2A, L1CAM, TCTE1, EBF3, SOX4, and HASH1 was up-regulated, although with different frequencies. Immunohistochemical staining detected high L1CAM expression selectively in 27 human pheochromocytomas but not in 140 nonchromaffin neuroendocrine tumors. These studies reveal clues to the molecular pathways involved in rat and human pheochromocytoma and identify previously unexplored biomarkers for clinical use.

Prognostic Value of Microscopic Tumor Necrosis in Adrenal Cortical Carcinoma.

Adrenal cortical carcinoma (ACC) is an uncommon neoplasm with variable prognosis. Several histologic criteria have been identified as predictors of malignancy in adrenal cortical tumors. The Weiss score is the system most widely employed for diagnostic purposes, but also possesses prognostic value. We aim to determine the relative impact of each Weiss parameter on ACC patient survival. A multicenter retrospective analysis was conducted on a series of 79 conventional ACCs surgically treated at the Florence and Utrecht centers of the European Network for the Study of Adrenal Tumors (ENSAT). Weiss classification was recapitulated using principal component analysis (PCA). The Kaplan-Meier and Cox multivariate regression analyses were applied in order to estimate the prognostic power of Weiss versus other clinical parameters. PCA reduced the nine Weiss parameters to the best fitting 4-component model, each parameter clustering with a single component. Necrosis and venous invasion clustered together with the highest scores, thus establishing the most relevant component (Component 1) to explain Weiss distribution variability. Only Component 1 significantly predicted overall survival (OS, log-rank = 0.008) and disease-free survival (DFS, log-rank < 0.001). When considering the prognostic power of Weiss parameters, necrosis alone could independently assess OS (log-rank = 0.004) and DFS (log-rank < 0.001) at both the Kaplan-Meier and multivariate Cox regression analyses [hazard ratio (HR) = 7.8, 95% confidence interval [CI] = 1.0-63.5, p = 0.05, and HR = 12.2, 95% CI = 1.6-95.0, p = 0.017, respectively]. The presence of necrosis significantly shortened time to survival (TtS) and time to recurrence (TtR), 57.5 [31.5-103.5] vs 34 [12-78] months (p = 0.05) and 57.5 [31.5-103.5] vs 7 [1.0-31.5] months (p < 0.001), respectively. Our study suggests that, of the Weiss parameters, necrosis is the most powerful adverse factor and the best predictor of OS and DFS in ACC patients.

Hypogonadism and sexual function in men affected by adrenocortical carcinoma under mitotane therapy.

Purpose: Adrenocortical carcinoma (ACC) is a rare and aggressive tumor. ACC male patients under adjuvant mitotane therapy (AMT) frequently develop hypogonadism, however sexual function has never been assessed in this setting. The aim of this retrospective study was to evaluate in AMT treated ACC patients the changes in Luteinizing hormone (LH), Sex Hormone Binding Globulin (SHBG), total testosterone (TT) and calculated free testosterone (cFT), the prevalence and type of hypogonadism and sexual function, the latter before and after androgen replacement therapy (ART). Methods: LH, SHBG, TT and cFT were assessed in ten ACC patients at baseline (T0) and six (T1), twelve (T2), and eighteen (T3) months after AMT. At T3, ART was initiated in eight hypogonadal patients, and LH, SHBG, TT and cFT levels were evaluated after six months (T4). In six patients, sexual function was evaluated before (T3) and after (T4) ART using the International Index of Erectile Function-15 (IIEF-15) questionnaire. Results: Under AMT we observed higher SHBG and LH and lower cFT levels at T1-T3 compared to T0 (all p<0.05). At T3, hypergonadotropic hypogonadism and erectile dysfunction (ED) were detected in 80% and 83.3% of cases. At T4, we observed a significant cFT increase in men treated with T gel, and a significant improvement in IIEF-15 total and subdomains scores and ED prevalence (16.7%) in men under ART. Conclusion: AMT was associated with hypergonatropic hypogonadism and ED, while ART led to a significant improvement of cFT levels and sexual function in the hypogonadal ACC patients. Therefore, we suggest to evaluate LH, SHBG, TT and cFT and sexual function during AMT, and start ART in the hypogonadal ACC patients with sexual dysfunction.

Functional study in a yeast model of a novel succinate dehydrogenase subunit B gene germline missense mutation (C191Y) diagnosed in a patient affected by a glomus tumor.

Mutations of succinate dehydrogenase (SDH) subunits B, C and D are associated to pheochromocytoma/paraganglioma (PGL) development. The mechanisms linking SDH mutations to tumorigenesis are currently unknown. We report a novel germline missense SDHB mutation (C191Y) in a patient affected by a glomus tumor. The missense mutation hits an amino acid residue conserved from mammals to the yeast Saccharomyces cerevisiae. The pathogenic significance of the human mutation was validated in a yeast model. SDH2(C184Y) mutant allele equivalent to human SDHB(C191Y) did not restore the OXPHOS phenotype of the Deltasdh2 null mutant. In the mutant, SDH activity was also abolished along with a reduction in respiration. Sensitivity to oxidative stress was increased in the mutant, as revealed by reduced growth in the presence of menadione. Remarkably, the frequency of petite colony formation was increased in the mutant yeast strain, indicating an increased mtDNA mutability. Histochemistry demonstrates that SDH activity was selectively absent in the patient tumor tissue. Overall, our results demonstrate that the C191Y SDHB mutation suppresses SDH enzyme activity leading to increased ROS formation and mtDNA mutability in our yeast model. These findings further our understanding of the mechanisms underlying PGL development and point to the yeast model as a valid tool to investigate on the possible pathogenic relevance of SDH novel mutations and/or rare polymorphism.

Circulating Fascin 1 as a Promising Prognostic Marker in Adrenocortical Cancer.

Fascin-1 (FSCN1) is an actin-bundling protein associated with an invasive and aggressive phenotype of several solid carcinomas, as it is involved in cell cytoskeleton rearrangement and filopodia formation. Adrenocortical carcinoma (ACC) is a rare endocrine malignancy characterized by poor prognosis, particularly when metastatic at diagnosis. Radical resection is the only therapeutic option for ACC patients in addition to the adjuvant treatment with mitotane. Novel specific biomarkers suggestive of tumor progression to refine diagnosis and prognosis of patients with advanced ACC are urgently needed. ACC intratumoral FSCN1 has previously been suggested as a valid prognostic marker. In the present study, we identified FSCN1 in the bloodstream of a small cohort of ACC patients (n = 27), through a specific ELISA assay for human FSCN1. FSCN1 can be detected in the serum, and its circulating levels were evaluated in pre-surgery samples, which resulted to be significantly higher in ACC patients from stage I/II and stage III/IV compared with nontumoral healthy controls (HC, n = 4, FI: 5.5 ± 0.8, P<0.001, and 8.0 ± 0.5, P < 0.001 for stage I/II and stage III/IV group vs HC, respectively). In particular, FSCN1 levels were significantly higher in advanced stage versus stage I/II (22.8 ± 1.1 vs 15.8 ± 1.8 ng/ml, P < 0.005, respectively). Interestingly, circulating levels of pre-surgical FSCN1 can significantly predict tumor progression/recurrence (Log rank = 0.013), but not the overall survival (Log rank=0.317), in patients stratified in high/low PreS FSCN1. In conclusion, these findings-though very preliminary-suggest that circulating FSCN1 may represent a new minimally-invasive prognostic marker in advanced ACC, in particular when measured before surgery enables histological diagnosis.

Stimulated Expression of CXCL12 in Adrenocortical Carcinoma by the PPARgamma Ligand Rosiglitazone Impairs Cancer Progression.

Adrenocortical carcinoma (ACC) is a rare malignancy with poor prognosis when metastatic and scarce treatment options in the advanced stages. In solid tumors, the chemokine CXCL12/CXCR4 axis is involved in the metastatic process. We demonstrated that the human adrenocortex expressed CXCL12 and its cognate receptors CXCR4 and CXCR7, not only in physiological conditions, but also in ACC, where the receptors' expression was higher and the CXCL12 expression was lower than in the physiological conditions. In a small pilot cohort of 22 ACC patients, CXCL12 negatively correlated with tumor size, stage, Weiss score, necrosis, and mitotic activity. In a Kaplan-Meier analysis, the CXCL12 tumor expression significantly predicted disease-free, progression-free, and overall survival. In vitro treatment of the primary ACC H295R and of the metastatic MUC-1 cell line with the PPARγ-ligand rosiglitazone (RGZ) dose-dependently reduced proliferation, resulting in a significant increase in CXCL12 and a decrease in its receptors in the H295R cells only, with no effect on the MUC-1 levels. In ACC mouse xenografts, tumor growth was inhibited by the RGZ treatment before tumor development (prevention-setting) and once the tumor had grown (therapeutic-setting), similarly to mitotane (MTT). This inhibition was associated with a significant suppression of the tumor CXCR4/CXCR7 and the stimulation of human CXCL12 expression. Tumor growth correlated inversely with CXCL12 and positively with CXCR4 expression, suggesting that local CXCL12 may impair the primary tumor cell response to the ligand gradient that may contribute to driving the tumor progression. These findings indicate that CXCL12/CXCR4 may constitute a potential target for anti-cancer agents such as rosiglitazone in the treatment of ACC.

A Multicenter Epidemiological Study on Second Malignancy in Non-Syndromic Pheochromocytoma/Paraganglioma Patients in Italy.

No studies have carried out an extensive analysis of the possible association between non-syndromic pheochromocytomas and paragangliomas (PPGLs) and other malignancies. To assess >the risk of additional malignancy in PPGL, we retrospectively evaluated 741 patients with PPGLs followed-up in twelve referral centers in Italy. Incidence of second malignant tumors was compared between this cohort and Italian patients with two subsequent malignancies. Among our patients, 95 (12.8%) developed a second malignant tumor, which were mainly prostate, colorectal and lung/bronchial cancers in males, breast cancer, differentiated thyroid cancer and melanoma in females. The standardized incidence ratio was 9.59 (95% CI 5.46-15.71) in males and 13.21 (95% CI 7.52-21.63) in females. At multivariable analysis, the risk of developing a second malignant tumor increased with age at diagnosis (HR 2.50, 95% CI 1.15-5.44, p = 0.021 for 50-59 vs. <50-year category; HR 3.46, 95% CI 1.67-7.15, p < 0.001 for >60- vs. <50-year). In patients with available genetic evaluation, a positive genetic test was inversely associated with the risk of developing a second tumor (HR 0.25, 95% CI 0.10-0.63, p = 0.003). In conclusion, PPGLs patients have higher incidence of additional malignant tumors compared to the general population who had a first malignancy, which could have an impact on the surveillance strategy.

Role of the PPAR-γ system in normal and tumoral pituitary corticotropic cells and adrenal cells.

PPAR-γ is a member of the nuclear hormone receptor superfamily of transcription factors, whose thiazolidinedione ligands (TZD) have been recently demonstrated to also possess anticancer properties in addition to their well-known insulin-sensitizer and glucose/lipid regulation activity. In this minireview, we summarize the current knowledge on PPAR-γ in normal and tumoral corticotropic pituitary and adrenal cells. The receptor expression has been shown in ACTH-secreting cells in both normal and adenomal pituitary as well as in normal and tumor adrenal cortex. Preclinical studies conducted both in vitro on tumor cells and in vivo on xenograft tumor models obtained by subcutaneous injection of cancer cells have evidenced the anticancer properties of TZD, in particular rosiglitazone (RGZ) and pioglitazone (PIO). In both pituitary and adrenocortical cancer, RGZ treatment results in inhibition of cell proliferation, through G0/G1 cell-cycle arrest and induction of cell apoptosis, leading to significant inhibition of tumor growth in the xenograft tumor models. In addition, since RGZ can reduce ACTH and corticosterone secretion in mouse corticotropic pituitary tumors, both RGZ and PIO have been used in the treatment of Cushing's disease with variable but generally unsatisfactory results. Discrepancies in the antitumor effects of TZD observed between successful preclinical and unsuccessful clinical studies may be particularly due to differences in treatment duration and doses used.

Spectrum and prevalence of FP/TMEM127 gene mutations in pheochromocytomas and paragangliomas.

CONTEXT: Pheochromocytomas and paragangliomas are genetically heterogeneous neural crest-derived neoplasms. We recently identified germline mutations of the novel transmembrane-encoding gene FP/TMEM127 in familial and sporadic pheochromocytomas consistent with a tumor suppressor effect. OBJECTIVES: To examine the prevalence and spectrum of FP/TMEM127 mutations in pheochromocytomas and paragangliomas and to test the effect of mutations in vitro. DESIGN, SETTING, AND PARTICIPANTS: We sequenced the FP/TMEM127 gene in 990 individuals with pheochromocytomas and/or paragangliomas, including 898 previously unreported cases without mutations in other susceptibility genes from 8 independent worldwide referral centers between January 2009 and June 2010. A multiplex polymerase chain reaction-based method was developed to screen for large gene deletions in 545 of these samples. Confocal microscopy of 5 transfected mutant proteins was used to determine their subcellular localization. MAIN OUTCOME MEASURES: The frequency and type of FP/TMEM127 mutation or deletion was assessed and correlated with clinical variables; the subcellular localization of 5 overexpressed mutants was compared with wild-type FP/TMEM127 protein. RESULTS: We identified 19 potentially pathogenic FP/TMEM127 germline mutations in 20 independent families, but no large deletions were detected. All mutation carriers had adrenal tumors, including 7 bilateral (P = 2.7 × 10(-4)) and/or with familial disease (5 of 20 samples; P = .005). The median age at disease onset in the FP/TMEM127 mutation group was similar to that of patients without a mutation (41.5 vs 45 years, respectively; P = .54). The most common presentation was that of a single benign adrenal tumor in patients older than 40 years. Malignancy was seen in 1 mutation carrier (5%). Expression of 5 novel FP/TMEM127 mutations in cell lines revealed diffuse localization of the mutant proteins in contrast with the discrete multiorganelle distribution of wild-type TMEM127. CONCLUSIONS: Germline mutations of FP/TMEM127 were associated with pheochromocytoma but not paraganglioma and occurred in an age group frequently excluded from genetic screening algorithms. Disease-associated mutations disrupt intracellular distribution of the FP/TMEM127 protein.

Prognostic and Monitoring Value of Circulating Tumor Cells in Adrenocortical Carcinoma: A Preliminary Monocentric Study.

Adrenocortical carcinoma (ACC), a rare and aggressive neoplasia, presents poor prognosis when metastatic at diagnosis and limited therapies are available. Specific and sensitive markers for early diagnosis and a monitoring system of therapy and tumor evolution are urgently needed. The liquid biopsy represents a source of tumor material within a minimally invasive blood draw that allows the recovery of circulating tumor cells (CTCs). CTCs have been recently shown to be detectable in ACC. In the present paper, we evaluated the prognostic value of CTCs obtained by size-filtration in a small pilot cohort of 19 ACC patients. We found CTCs in 68% of pre-surgery and in 38% of post-surgery blood samples. In addition, CTC clusters (CTMs) and cancer associated macrophages (CAMLs) were detectable in some ACC patients. The median number of CTCs significantly decreased after the mass removal. Finally, stratifying patients in high and low pre-surgery CTC number groups, assuming the 75th percentile CTC value as cut-off, CTCs significantly predicted patients' overall survival (log rank = 0.005), also in a multivariate analysis adjusted for age and tumor stage. In conclusion, though preliminary and performed in a small cohort of patients, our study suggests that CTC number may represent a promising marker for prognosis and disease monitoring in ACC.