Research IndicatorsGraph generated 01 September 2019 using data from PubMed using criteria.
Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic. Tag cloud generated 01 September, 2019 using data from PubMed, MeSH and CancerIndex
Specific Cancers (6)
Data table showing topics related to specific cancers and associated disorders. Scope includes mutations and abnormal protein expression.
Note: list is not exhaustive. Number of papers are based on searches of PubMed (click on topic title for arbitrary criteria used).
OMIM, Johns Hopkin University
Referenced article focusing on the relationship between phenotype and genotype.
International Cancer Genome Consortium.
Summary of gene and mutations by cancer type from ICGC
Cancer Genome Anatomy Project, NCI
COSMIC, Sanger Institute
Somatic mutation information and related details
GEO Profiles, NCBI
Search the gene expression profiles from curated DataSets in the Gene Expression Omnibus (GEO) repository.
Latest Publications: PDE11A (cancer-related)
Shahi RB, De Brakeleer S, Caljon B, et al.Identification of candidate cancer predisposing variants by performing whole-exome sequencing on index patients from BRCA1 and BRCA2-negative breast cancer families.
BMC Cancer. 2019; 19(1):313 [PubMed
] Free Access to Full Article Related Publications
BACKGROUND: In the majority of familial breast cancer (BC) families, the etiology of the disease remains unresolved. To identify missing BC heritability resulting from relatively rare variants (minor allele frequency ≤ 1%), we have performed whole exome sequencing followed by variant analysis in a virtual panel of 492 cancer-associated genes on BC patients from BRCA1 and BRCA2 negative families with elevated BC risk.
METHODS: BC patients from 54 BRCA1 and BRCA2-negative families with elevated BC risk and 120 matched controls were considered for germline DNA whole exome sequencing. Rare variants identified in the exome and in a virtual panel of cancer-associated genes [492 genes associated with different types of (hereditary) cancer] were compared between BC patients and controls. Nonsense, frame-shift indels and splice-site variants (strong protein-damaging variants, called PDAVs later on) observed in BC patients within the genes of the panel, which we estimated to possess the highest probability to predispose to BC, were further validated using an alternative sequencing procedure.
RESULTS: Exome- and cancer-associated gene panel-wide variant analysis show that there is no significant difference in the average number of rare variants found in BC patients compared to controls. However, the genes in the cancer-associated gene panel with nonsense variants were more than two-fold over-represented in women with BC and commonly involved in the DNA double-strand break repair process. Approximately 44% (24 of 54) of BC patients harbored 31 PDAVs, of which 11 were novel. These variants were found in genes associated with known or suspected BC predisposition (PALB2, BARD1, CHEK2, RAD51C and FANCA) or in predisposing genes linked to other cancer types but not well-studied in the context of familial BC (EXO1, RECQL4, CCNH, MUS81, TDP1, DCLRE1A, DCLRE1C, PDE11A and RINT1) and genes associated with different hereditary syndromes but not yet clearly associated with familial cancer syndromes (ABCC11, BBS10, CD96, CYP1A1, DHCR7, DNAH11, ESCO2, FLT4, HPS6, MYH8, NME8 and TTC8). Exome-wide, only a few genes appeared to be enriched for PDAVs in the familial BC patients compared to controls.
CONCLUSIONS: We have identified a series of novel candidate BC predisposition variants/genes. These variants/genes should be further investigated in larger cohorts/case-control studies. Other studies including co-segregation analyses in affected families, locus-specific loss of heterozygosity and functional studies should shed further light on their relevance for BC risk.
Candida Barisson Villares Fragoso M, Pontes Cavalcante I, Meneses Ferreira A, et al.Genetics of primary macronodular adrenal hyperplasia.
Presse Med. 2018 Jul - Aug; 47(7-8 Pt 2):e139-e149 [PubMed
] Related Publications
Recent advances in molecular genetics investigations of primary macronodular adrenal hyperplasia (PMAH) have been providing new insights for the research on this issue. The cAMP-dependent pathway is physiologically triggered by ACTH and its receptor, MC2-R, in adrenocortical cells. Different mechanisms of this cascade may be altered in some functioning adrenal cortical disorders. Activating somatic mutations of the GNAS gene (known as gsp oncogene) which encodes the stimulatory G protein alpha-subunit (Gsα) have been found in a small number of adrenocortical secreting adenomas and rarely in PMAH. Lately, ARMC5 was linked to the cyclic AMP signaling pathway, which could be implicated in all of mechanisms of cortisol-secreting by macronodules adrenal hyperplasia and the molecular defects in: G protein aberrant receptors; MC2R; GNAS; PRKAR1A; PDE11A; PDE8B. Around 50 % of patient's relatives with PMAH and 30 % of apparently sporadic hypercortisolism carried ARMC5 mutations. Therefore, PMAH is genetically determined more frequently than previously believed. This review summarizes the most important molecular mechanisms involved in PMAH.
Germline inactivating mutations of isoform 4 of phosphodiesterase (PDE) 11A (coded by the PDE11A gene) have been associated with familial adrenocortical tumors and familial testicular cancer. Testicular tissue is unique in expressing all four isoforms of PDE11A. In a prior candidate gene study of 94 familial testicular germ cell tumor (TGCT) subjects, we identified a significant association between the presence of functionally abnormal variants in PDE11A and familial TGCT risk. To validate this novel observation, we sequenced the PDE11A coding region in 259 additional TGCT patients (both familial and sporadic) and 363 controls. We identified 55 PDE11A variants: 20 missense, four splice-site, two nonsense, seven synonymous, and 22 intronic. Ten missense variants were novel; nine occurred in transcript variant 4 and one in transcript variant 3. Five rare mutations (p.F258Y, p.G291R, p.V820M, p.R545X, and p.K568R) were present only in cases and were significantly more common in cases vs controls (P=0.0037). The latter two novel variants were functionally characterized and shown to be functionally inactivating, resulting in reduced PDE activity and increased cAMP levels. In further analysis of this cohort, we focused on white participants only to minimize confounding due to population stratification. This study builds upon our prior reports implicating PDE11A variants in familial TGCT, provides the first independent validation of those findings, extends that work to sporadic testicular cancer, demonstrates that these variants are uncommonly but reproducibly associated with TGCT, and refines our understanding regarding which specific inactivating PDE11A variants are most likely to be associated with TGCT risk.
Duan K, Gomez Hernandez K, Mete OClinicopathological correlates of adrenal Cushing's syndrome.
J Clin Pathol. 2015; 68(3):175-86 [PubMed
] Related Publications
Endogenous Cushing's syndrome is a rare endocrine disorder that incurs significant cardiovascular morbidity and mortality, due to glucocorticoid excess. It comprises adrenal (20%) and non-adrenal (80%) aetiologies. While the majority of cases are attributed to pituitary or ectopic corticotropin (ACTH) overproduction, primary cortisol-producing adrenal cortical lesions are increasingly recognised in the pathophysiology of Cushing's syndrome. Our understanding of this disease has progressed substantially over the past decade. Recently, important mechanisms underlying the pathogenesis of adrenal hypercortisolism have been elucidated with the discovery of mutations in cyclic AMP signalling (PRKACA, PRKAR1A, GNAS, PDE11A, PDE8B), armadillo repeat containing 5 gene (ARMC5) a putative tumour suppressor gene, aberrant G-protein-coupled receptors, and intra-adrenal secretion of ACTH. Accurate subtyping of Cushing's syndrome is crucial for treatment decision-making and requires a complete integration of clinical, biochemical, imaging and pathology findings. Pathological correlates in the adrenal glands include hyperplasia, adenoma and carcinoma. While the most common presentation is diffuse adrenocortical hyperplasia secondary to excess ACTH production, this entity is usually treated with pituitary or ectopic tumour resection. Therefore, when confronted with adrenalectomy specimens in the setting of Cushing's syndrome, surgical pathologists are most commonly exposed to adrenocortical adenomas, carcinomas and primary macronodular or micronodular hyperplasia. This review provides an update on the rapidly evolving knowledge of adrenal Cushing's syndrome and discusses the clinicopathological correlations of this important disease.
The majority of benign adrenal cortex lesions leading to Cushing syndrome are associated to one or another abnormality of the cAMP/cGMP-phosphodiesterase signaling pathway. Phosphodiesterases (PDEs) are key regulatory enzymes of intracellular cAMP/cGMP levels. These second messengers play important regulatory roles in controlling steroidogenesis in the adrenal. Disruption of PDEs has been associated with a number of adrenal diseases. Specifically, genetic mutations have been associated with benign adrenal lesions, leading to Cushing syndrome and/or related adrenal hyperplasias. A Genome Wide Association study, in 2006, led to the identification of mutations in 2 PDE genes: PDE8B and PDE11A; mutations in these 2 genes modulate steroidogenesis. Further human studies have identified PDE2 as also directly regulating steroidogenesis. PDE2 decreases aldosterone production. This review focuses on the most recent knowledge we have gained on PDEs and their association with adrenal steroidogenesis and altered function, through analysis of patient cohorts and what we have learned from mouse studies.
BACKGROUND: Familial testicular germ cell tumors (FTGCTs) are hypothesized to result from the combined interaction of multiple low-penetrance genes. We reported inactivating germline mutations of the cAMP-binding phosphodiesterase 11A (PDE11A) as modifiers of FTGCT risk. Recent genome-wide association studies have identified single-nucleotide polymorphisms in the KITLG gene, the ligand for the cKIT tyrosine kinase receptor, as strong modifiers of susceptibility to both familial and sporadic testicular germ cell tumors.
DESIGN: We studied 94 patients with FTGCTs and 50 at-risk male relatives from 63 unrelated kindreds, in whom the PDE11A gene had been sequenced by investigating the association between KITLG genome-wide association study single-nucleotide polymorphisms rs3782179 and rs4474514 and FTGCT risk in these patients and in 692 controls. We also examined cAMP and c-KIT signaling in testicular tissues and cell lines and extended the studies to 2 sporadic cases, one with a PDE11A defect and one without, as a comparison.
RESULTS: We found a higher frequency of the KITLG risk alleles in FTGCT patients who also had a PDE11A sequence variant, compared with those with a wild-type PDE11A sequence. In NTERA-2 and Tcam-2 cells transfected with the mutated forms of PDE11A (R52T, F258Y, Y727C, R804H, V820M, R867G, and M878V), cAMP levels were significantly higher, and the relative phosphodiesterase activity was lower than in the wild-type cells. KITLG expression was consistently increased in the presence of PDE11A-inactivating defects, both at the RNA and protein levels, in familial testicular germ cell tumors. The 2 sporadic cases that were studied, one with a PDE11A defect and another without, agreed with the data in FTGTCT and in the cell lines.
CONCLUSIONS: Patients with FTGCT and PDE11A defects also carry KITLG risk alleles more frequently. There may be an interaction between cAMP and c-KIT signaling in predisposition to testicular germ cell tumors.
Integration of the viral DNA into host chromosomes was found in most of the hepatitis B virus (HBV)-related hepatocellular carcinomas (HCCs). Here we devised a massive anchored parallel sequencing (MAPS) method using next-generation sequencing to isolate and sequence HBV integrants. Applying MAPS to 40 pairs of HBV-related HCC tissues (cancer and adjacent tissues), we identified 296 HBV integration events corresponding to 286 unique integration sites (UISs) with precise HBV-Human DNA junctions. HBV integration favored chromosome 17 and preferentially integrated into human transcript units. HBV targeted genes were enriched in GO terms: cAMP metabolic processes, T cell differentiation and activation, TGF beta receptor pathway, ncRNA catabolic process, and dsRNA fragmentation and cellular response to dsRNA. The HBV targeted genes include 7 genes (PTPRJ, CNTN6, IL12B, MYOM1, FNDC3B, LRFN2, FN1) containing IPR003961 (Fibronectin, type III domain), 7 genes (NRG3, MASP2, NELL1, LRP1B, ADAM21, NRXN1, FN1) containing IPR013032 (EGF-like region, conserved site), and three genes (PDE7A, PDE4B, PDE11A) containing IPR002073 (3', 5'-cyclic-nucleotide phosphodiesterase). Enriched pathways include hsa04512 (ECM-receptor interaction), hsa04510 (Focal adhesion), and hsa04012 (ErbB signaling pathway). Fewer integration events were found in cancers compared to cancer-adjacent tissues, suggesting a clonal expansion model in HCC development. Finally, we identified 8 genes that were recurrent target genes by HBV integration including fibronectin 1 (FN1) and telomerase reverse transcriptase (TERT1), two known recurrent target genes, and additional novel target genes such as SMAD family member 5 (SMAD5), phosphatase and actin regulator 4 (PHACTR4), and RNA binding protein fox-1 homolog (C. elegans) 1 (RBFOX1). Integrating analysis with recently published whole-genome sequencing analysis, we identified 14 additional recurrent HBV target genes, greatly expanding the HBV recurrent target list. This global survey of HBV integration events, together with recently published whole-genome sequencing analyses, furthered our understanding of the HBV-related HCC.
Vezzosi D, Libé R, Baudry C, et al.Phosphodiesterase 11A (PDE11A) gene defects in patients with acth-independent macronodular adrenal hyperplasia (AIMAH): functional variants may contribute to genetic susceptibility of bilateral adrenal tumors.
J Clin Endocrinol Metab. 2012; 97(11):E2063-9 [PubMed
] Free Access to Full Article Related Publications
CONTEXT: Phosphodiesterases (PDEs) are key regulatory enzymes of intracellular cAMP levels. PDE11A function has been linked to predisposition to adrenocortical tumors.
OBJECTIVE: The aim of the study was to study the PDE11A gene in a large cohort of patients with ACTH-independent macronodular adrenal hyperplasia (AIMAH) and in control subjects.
DESIGN: The PDE11A entire coding region was sequenced in 46 patients with AIMAH and 192 controls. Two variants found in AIMAH patients were transiently expressed in HEK 293 and adrenocortical H295R cells for further functional studies.
RESULTS: The frequency of all PDE11A variants was significantly higher among patients with AIMAH (28%) compared to controls (7.2%) (P = 5 × 10(-5)). Transfection of the two PDE11A variants found in AIMAH patients only (D609N or M878V) showed that cAMP levels were higher, after forskolin stimulation, in cells transfected with the PDE11A mutants, compared to cells transfected with the wild-type PDE11A in HEK 293 cells (P < 0.05). Moreover, transfection with mutants PDE11A increased transcriptional activity of a cAMP-response element reporter construct compared to wild-type PDE11A in HEK 293 cells (P < 0.0004 for D609N and P < 0.003 for M878V) and in the adrenocortical H295R cells (P < 0.05 for D609N and M878V). In addition, analysis of cAMP levels in intact living culture cells by fluorescence resonance energy transfer probes showed increased cAMP in forskolin-treated cells transfected with PDE11A variants compared with wild-type PDE11A (P < 0.05).
CONCLUSION: We conclude that PDE11A genetic variants may increase predisposition to AIMAH.
Tung SC, Hwang DY, Yang JW, et al.An unusual presentation of Carney complex with diffuse primary pigmented nodular adrenocortical disease on one adrenal gland and a nonpigmented adrenocortical adenoma and focal primary pigmented nodular adrenocortical disease on the other.
Endocr J. 2012; 59(9):823-30 [PubMed
] Related Publications
A 24-year-old female patient with cushingoid appearance was admitted in May 2000. The endocrine studies showed ACTH-independent Cushing's syndrome. A 2-day high-dose dexamethasone suppression test (HDDST) revealed paradoxical increase of 24 h urinary free cortisol (UFC). Abdominal computed tomography demonstrated a left adrenal nodule (3 x 2 cm in diameter). An adrenal scintigram with ¹³¹I-6β-iodomethyl-19-norcholesterol showed uptake of the isotope in the left adrenal gland and non-visualization in the right adrenal gland throughout the examination course. A retroperitoneoscopic left total adrenalectomy was performed in July 2000. The cut surface of the left adrenal was yellow-tan grossly. Microscopically, the left adrenal nodule contained a nonpigmented adrenocortical adenoma (NP) and another focal primary pigmented nodular adrenocortical disease (PPNAD, FP) mixed lesion. The immunohistochemical studies of CYP17 demonstrate positive in NP and FP of the left adrenal gland. Very low baseline morning plasma cortisol (0.97 μg/dL) and subnormal ACTH (8.16 pg/mL) levels were measured 1.5 months after left adrenalectomy. Right adrenal gland recovered its function 6 months after left adrenalectomy. Plasma cortisol could be suppressed to 3.47 μg/dL by overnight low-dose dexamethasone suppression test 65 months after left adrenalectomy. Cushingoid features still did not appear 122 months after left adrenalectomy. In May 2011, this patient was readmitted due to cushingoid characteristics. Paradoxical rise of 24-h UFC to 2-day HDDST was demonstrated. Ultrasonography of thyroid showed bilateral thyroid cysts. Subtotal right adrenalectomy about 80% of right adrenal was performed. Diffuse PPNAD of the right adrenal was proved pathologically. Immunohischemical stain for CYP17 is positive in the right adrenal gland but weaker positive than that in the left adrenal gland. The genetic study of the peripheral blood, left adrenocortical nodule, and right PPNAD all showed p.R16X (c.46C>T) mutation of the PRKAR1A gene.
Phosphodiesterases (PDEs) are enzymes that regulate the intracellular levels of cyclic adenosine monophosphate and cyclic guanosine monophosphate, and, consequently, exhibit a central role in multiple cellular functions. The pharmacological exploitation of the ability of PDEs to regulate specific pathways has led to the discovery of drugs with selective action against specific PDE isoforms. Considerable attention has been given to the development of selective PDE inhibitors, especially after the therapeutic success of PDE5 inhibitors in the treatment of erectile dysfunction. Several associations between PDE genes and genetic diseases have been described, and more recently PDE11A and PDE8B have been implicated in predisposition to tumor formation. This review focuses on the possible function of PDEs in a variety of tumors, primarily in endocrine glands, both in tumor predisposition and as potential therapeutic targets.
Carney complex (CNC) is a multiple neoplasia syndrome that is inherited in an autosomal dominant manner and is characterized by skin tumors and pigmented lesions, myxomas, schwannomas, and various endocrine tumors. Inactivating mutations of the PRKAR1A gene coding for the regulatory type I-α (RIα) subunit of protein kinase A (PKA) are responsible for the disease in most CNC patients. The overall penetrance of CNC among PRKAR1A mutation carriers is near 98%. Most PRKAR1A mutations result in premature stop codon generation and lead to nonsense-mediated mRNA decay. CNC is genetically and clinically heterogeneous, with specific mutations providing some genotype-phenotype correlation. Phosphodiesterase-11A (the PDE11A gene) and -8B (the PDE8B gene) mutations were found in patients with isolated adrenal hyperplasia and Cushing syndrome, as well in patients with PPNAD. Recent evidences demonstrated that dysregulation of cAMP/PKA pathway can modulate other signaling pathways and contributes to adrenocortical tumorigenesis.
The overwhelming majority of benign lesions of the adrenal cortex leading to Cushing syndrome are linked to one or another abnormality of the cAMP signaling pathway. A small number of both massive macronodular adrenocortical disease and cortisol-producing adenomas harbor somatic GNAS mutations. Micronodular adrenocortical hyperplasias are either pigmented (the classic form being that of primary pigmented nodular adrenocortical disease) or non-pigmented; micronodular adrenocortical hyperplasias can be seen in the context of other conditions or isolated; for example, primary pigmented nodular adrenocortical disease usually occurs in the context of Carney complex, but isolated primary pigmented nodular adrenocortical disease has also been described. Both Carney complex and isolated primary pigmented nodular adrenocortical disease are caused by germline PRKAR1A mutations; somatic mutations of this gene that regulates cAMP-dependent protein kinase are also found in cortisol-producing adenomas, and abnormalities of PKA are present in most cases of massive macronodular adrenocortical disease. Micronodular adrenocortical hyperplasias and some cortisol-producing adenomas are associated with phosphodiesterase 11A and 8B defects, coded, respectively, by the PDE11A and PDE8B genes. Mouse models of Prkar1a deficiency also show that increased cAMP signaling leads to tumors in adrenal cortex and other tissues. In this review, we summarize all recent data from ours and other laboratories, supporting the view that Wnt-signaling acts as an important mediator of tumorigenicity induced by abnormal PRKAR1A function and aberrant cAMP signaling.
Libé R, Horvath A, Vezzosi D, et al.Frequent phosphodiesterase 11A gene (PDE11A) defects in patients with Carney complex (CNC) caused by PRKAR1A mutations: PDE11A may contribute to adrenal and testicular tumors in CNC as a modifier of the phenotype.
J Clin Endocrinol Metab. 2011; 96(1):E208-14 [PubMed
] Free Access to Full Article Related Publications
BACKGROUND: Carney complex (CNC) is an autosomal dominant multiple neoplasia, caused mostly by inactivating mutations of the regulatory subunit 1A of the protein kinase A (PRKAR1A). Primary pigmented nodular adrenocortical disease (PPNAD) is the most frequent endocrine manifestation of CNC with a great inter-individual variability. Germline, protein-truncating mutations of phosphodiesterase type 11A (PDE11A) have been described to predispose to a variety of endocrine tumors, including adrenal and testicular tumors.
OBJECTIVES: Our objective was to investigate the role of PDE11A as a possible gene modifier of the phenotype in a series of 150 patients with CNC.
RESULTS: A higher frequency of PDE11A variants in patients with CNC compared with healthy controls was found (25.3 vs. 6.8%, P < 0.0001). Among CNC patients, those with PPNAD were significantly more frequently carriers of PDE11A variants compared with patients without PPNAD (30.8 vs. 13%, P = 0.025). Furthermore, men with PPNAD were significantly more frequently carriers of PDE11A sequence variants (40.7%) than women with PPNAD (27.3%) (P < 0.001). A higher frequency of PDE11A sequence variants was also found in patients with large-cell calcifying Sertoli cell tumors (LCCSCT) compared with those without LCCSCT (50 vs. 10%, P = 0.0056). PDE11A variants were significantly associated with the copresence of PPNAD and LCCSCT in men: 81 vs. 20%, P < 0.004). The simultaneous inactivation of PRKAR1A and PDE11A by small inhibitory RNA led to an increase in cAMP-regulatory element-mediated transcriptional activity under basal conditions and after stimulation by forskolin.
CONCLUSIONS: We demonstrate, in a large cohort of CNC patients, a high frequency of PDE11A variants, suggesting that PDE11A is a genetic modifying factor for the development of testicular and adrenal tumors in patients with germline PRKAR1A mutation.
CONTEXT: Among the genomic loci harboring potential candidate genes for prostatic cancer (PCa) is the 2q31-33 chromosomal region that harbors the gene encoding phosphodiesterase 11A (PDE11A). In addition, the combined cancer genome expression metaanalysis datasets included PDE11A among the top 1% down-regulated genes in PCa.
OBJECTIVE: In the present study, we screened 50 unrelated PCa patients of Brazilian descent for PDE11A coding defects.
DESIGN: The study consisted of PDE11A sequencing, in vitro functional assays, and immunostaining analysis.
RESULTS: We identified eight different sequence alterations in 15 patients (30%): one stop-codon and seven missense mutations. Three of the variants (R202C, Y658C, and E840K) were novel, and the remaining five (Y727C, R804H, R867G, M878V, and R307X) have been associated with predisposition to adrenal or testicular tumors. The overall prevalence of PDE11A-inactivating sequence variants among PCa patients was significantly higher than in 287 healthy controls (0.16 vs. 0.051, respectively, P < 0.001, odds ratio 3.81, 95% confidence interval 1.86-7.81) and the R202C, Y658C, and E840K substitutions were not found in controls. All missense mutations led to decreased PDE11A activity in human embryonic kidney 293 and PC3M cells and immunostaining of PCa samples with sequence changes showed decreased PDE11A protein expression.
CONCLUSION: Our data suggest that, like in the adrenal cortex and the testicular germ cells, PDE11A-inactivating genetic alterations may play a role in susceptibility to PCa.
Yaneva M, Vandeva S, Zacharieva S, et al.Genetics of Cushing's syndrome.
Neuroendocrinology. 2010; 92 Suppl 1:6-10 [PubMed
] Related Publications
Cushing's syndrome (CS) is characterized by pathologically elevated free glucocorticoid levels. Endogenous hypercortisolism is usually due to ACTH-secreting pituitary corticotropic adenomas and less often due to ectopic ACTH-secreting neuroendocrine neoplasms or ACTH-independent adrenal cortisol hypersecretion. CS is a serious chronic disease leading to a several-fold increase in cardiovascular morbidity and mortality. Multiple genetic alterations have been described in the setting of sporadic corticotropinoma formation. Changes in the expression profiles have been demonstrated in growth factors and their receptors, cell-cycle regulators and in various genes related to hormonal gene transcription, synthesis and secretion. Sporadic adrenal adenomas and carcinomas may demonstrate dysfunction in genes such as TP53 among others. Cushing's disease can be an inherited condition also. Multiple endocrine neoplasia type 1 (MEN1) and familial isolated pituitary adenomas (FIPA) together account for 5% of pituitary adenomas. Cushing's disease occurs infrequently in an inherited setting in both of these conditions. To date only 2 cases of Cushing's disease have been described in association with mutations in AIP. One case of Cushing's disease has been reported as part of MEN4, a rare MEN1-like syndrome due to mutation in the CDKN1B gene. Carney complex (CNC) due to PRKAR1A mutations in most cases is associated with CS, mainly as a cause of bilateral adrenal hyperplasia. The cAMP signaling pathway is affected in this setting. In recent times the involvement of genes such as PDE11A, PDE8B and others have expanded the spectrum of the genetic pathophysiology of CS.
This article defines familial testicular germ cell tumours (FTGCTs) as testicular germ cell tumours (TGCTs) diagnosed in at least two blood relatives, a situation which occurs in 1-2% of all cases of TGCT. Brothers and fathers of TGCT patients have an 8-10- and 4-6-fold increased risk of TGCT, respectively, and an even higher elevated risk of TGCT in twin brothers of men with TGCT has been observed, suggesting that genetic elements play an important role in these tumours. Nevertheless, previous linkage studies with multiple FTGCT families did not uncover any high-penetrance genes and it has been concluded that the combined effects of multiple common alleles, each conferring a modest risk, might underlie FTGCT. In agreement with this assumption, recent candidate gene-association analyses have identified the chromosome Y gr/gr deletion and mutations in the PDE11A gene as genetic modifiers of FTGCT risk. Moreover, two genome-wide association studies of predominantly sporadic but also familial cases of TGCT have identified three additional susceptibility loci, KITLG, SPRY4 and BAK1. Notably, all five loci are involved in the biology of primordial germ cells, representing the cell of origin of TGCT, suggesting that the tumours arise as a result of disturbed testicular development.
Familial aggregations of testicular germ cell tumor (FTGCT) have been well described, suggesting the existence of a hereditary TGCT subset. Approximately 1.4% of newly diagnosed TGCT patients report a positive family history of TGCT. Sons and siblings of TGCT patients have four- to sixfold and eight- to tenfold increases in TGCT risk respectively. Segregation analyses suggest an autosomal recessive mode of inheritance. Linkage analyses have identified several genomic regions of modest interest, although no high-penetrance cancer susceptibility gene has been mapped yet. These data suggest that the combined effects of multiple common alleles, each conferring modest risk, might underlie familial testicular cancer. Families display a mild phenotype: the most common number of affected families is 2. Age at diagnosis is 2-3 years younger for familial versus sporadic cases. The ratio of familial seminoma to nonseminoma is 1.0. FTGCT is more likely to be bilateral than sporadic TGCT. This syndrome is cancer site specific. Testicular microlithiasis is a newly recognized FTGCT component. Candidate gene-association studies have implicated the Y chromosome gr/gr deletion and PDE11A gene mutations as genetic modifiers of FTGCT risk. Two genomewide association studies of predominantly sporadic but also familial cases of TGCT have implicated the KIT-ligand, SPRY4, and BAK1 genes as TGCT risk modifiers. All five loci are involved in normal testicular development and/or male infertility. These genetic data provide a novel insight into the genetic basis of FTGCT, and an invaluable guide to future TGCT research.
CONTEXT: Bilateral micronodular adrenal hyperplasia and ectopic adrenocortical adenoma are two rare causes of ACTH-independent Cushing's syndrome.
OBJECTIVE: The aim of the study was to evaluate a 35-yr-old woman with ACTH-independent hypercortisolism associated with both micronodular adrenal hyperplasia and ectopic pararenal adrenocortical adenoma.
DESIGN AND SETTING: In vivo and in vitro studies were performed in a University Hospital Department and academic research laboratories.
INTERVENTION: Mutations of the PRKAR1A, PDE8B, and PDE11A genes were searched for in leukocytes and adrenocortical tissues. The ability of adrenal and adenoma tissues to synthesize cortisol was investigated by immunohistochemistry, quantitative PCR, and/or cell culture studies.
MAIN OUTCOME MEASURE: Detection of 17alpha-hydroxylase and 21-hydroxylase immunoreactivities, quantification of CYP11B1 mRNA in adrenal and adenoma tissues, and measurement of cortisol levels in supernatants by radioimmunological assays were the main outcomes.
RESULTS: Histological examination of the adrenals revealed nonpigmented micronodular cortical hyperplasia associated with relative atrophy of internodular cortex. No genomic and/or somatic adrenal mutations of the PRKAR1A, PDE8B, and PDE11A genes were detected. 17alpha-Hydroxylase and 21-hydroxylase immunoreactivities as well as CYP11B1 mRNA were detected in adrenal and adenoma tissues. ACTH and dexamethasone activated cortisol secretion from adenoma cells. The stimulatory action of dexamethasone was mediated by a nongenomic effect involving the protein kinase A pathway.
CONCLUSION: This case suggests that unknown molecular defects can favor both micronodular adrenal hyperplasia and ectopic adrenocortical adenoma associated with Cushing's syndrome.
Peverelli E, Ermetici F, Filopanti M, et al.Analysis of genetic variants of phosphodiesterase 11A in acromegalic patients.
Eur J Endocrinol. 2009; 161(5):687-94 [PubMed
] Related Publications
OBJECTIVES: Aberrant cAMP signaling is involved in the pathogenesis of somatotropinomas. The aim of the study was to screen acromegalic patients for the presence of variants of phosphodiesterase type 11A (PDE11A) gene, which have been recently identified in adrenocortical and testicular tumors.
SUBJECTS AND METHODS: We sequenced the PDE11A gene-coding region in 78 acromegalic patients and 110 controls. Immunohistochemistry for PDE11A was performed in a subgroup of adenomas and normal pituitary samples.
RESULTS: We found 15 nonsynonymous germline substitutions in 13 acromegalic patients (17%), i.e. 14 missense variants (Y727C in six, R804H in one, R867G in four, and M878V in three) and one truncating mutation (FS41X), with a prevalence only slightly higher than that observed in controls (14%). Immunohistochemistry revealed PDE11A expression higher in somatotropinomas than in normal somatotrophs, without significant difference between tumors with or without PDE11A variants, with the exception of two tumors (one with loss of heterozygosity (LOH) at the PDE11A locus and one with FS41X mutation) showing markedly reduced PDE11A staining. No significant differences in hormonal and clinical parameters between patients with or without PDE11A variants were observed, although patients with PDE11A changes showed a tendency to have a more aggressive tumor compared with patients with wild-type sequence (extrasellar extension in 69 vs 45%).
CONCLUSIONS: This study first demonstrated the presence of PDE11A variants in a subset of acromegalic patients, which was only slightly more frequent than in controls. The normal expression of the enzyme in the majority of tumor tissues together with the lack of significant clinical phenotype suggests that these variants might only marginally contribute to the development of somatotropinomas.
Inactivating germline mutations in phosphodiesterase 11A (PDE11A) have been implicated in adrenal tumor susceptibility. PDE11A is highly expressed in endocrine steroidogenic tissues, especially the testis, and mice with inactivated Pde11a exhibit male infertility, a known testicular germ cell tumor (TGCT) risk factor. We sequenced the PDE11A gene-coding region in 95 patients with TGCT from 64 unrelated kindreds. We identified 8 nonsynonymous substitutions in 20 patients from 15 families: four (R52T, F258Y, G291R, and V820M) were newly recognized, three (R804H, R867G, and M878V) were functional variants previously implicated in adrenal tumor predisposition, and one (Y727C) was a known polymorphism. We compared the frequency of these variants in our patients to unrelated controls that had been screened and found negative for any endocrine diseases: only the two previously reported variants, R804H and R867G, known to be frequent in general population, were detected in these controls. The frequency of all PDE11A-gene variants (combined) was significantly higher among patients with TGCT (P = 0.0002), present in 19% of the families of our cohort. Most variants were detected in the general population, but functional studies showed that all these mutations reduced PDE activity, and that PDE11A protein expression was decreased (or absent) in TGCT samples from carriers. This is the first demonstration of the involvement of a PDE gene in TGCT, although the cyclic AMP signaling pathway has been investigated extensively in reproductive organ function and their diseases. In conclusion, we report that PDE11A-inactivating sequence variants may modify the risk of familial and bilateral TGCT.
Several important advances have been made over the last 2 years, since the last international workshop on multiple endocrine neoplasias (MENs) that was held in Marseilles, France (MEN2006). The series of articles that are included in this issue summarize the most important of these advances as they were presented in Delphi, Greece, during the 11th International Workshop on MENs, September 25-27, 2008 (MEN2008). This editorial summarizes some of these advances: the identification of the AIP, and the PDE11A and PDE8B genes by genome-wide association (GWA) studies as predisposing genes for pituitary and adrenal tumours, respectively, the discovery of p27 mutations in a new form of MEN similar to MEN type 1 (MEN 1) that is now known as MEN 4, the molecular investigations of Carney triad (CT), a disorder that associates paragangliomas (PGLs), gastrointestinal stromal tumour (GISTs), and pulmonary chondromas (PCH) with pheochromocytomas and adrenocortical adenomas and other lesions, and the molecular elucidation of the association of GISTs with paragangliomas (Carney-Stratakis syndrome) that is now known to be because of SDHB, SDHC, and SDHD mutations. Molecular investigations in Carney complex (another MEN also described by Dr. Carney, who during the meeting, along with Dr. Charles E. ('Gene') Jackson was honoured for his life-long and many contributions to the field) have also revealed the role of cyclic AMP signalling in tumorigenesis. As our knowledge of the molecular causes of MENs increases, the challenge is to translate these discoveries in better treatments for our patients. Indeed, new advances in the preventive diagnosis and molecular treatment of MEN 1 and MEN 2, respectively, continued unabated, and an update on this front was also presented at MEN2008 and is included in this issue.
Hsiao HP, Kirschner LS, Bourdeau I, et al.Clinical and genetic heterogeneity, overlap with other tumor syndromes, and atypical glucocorticoid hormone secretion in adrenocorticotropin-independent macronodular adrenal hyperplasia compared with other adrenocortical tumors.
J Clin Endocrinol Metab. 2009; 94(8):2930-7 [PubMed
] Free Access to Full Article Related Publications
OBJECTIVE: ACTH-independent macronodular adrenal hyperplasia (AIMAH) is often associated with subclinical cortisol secretion or atypical Cushing's syndrome (CS). We characterized a large series of patients of AIMAH and compared them with patients with other adrenocortical tumors.
DESIGN AND PATIENTS: We recruited 82 subjects with: 1) AIMAH (n = 16); 2) adrenocortical cortisol-producing adenoma with CS (n = 15); 3) aldosterone-producing adenoma (n = 19); and 4) single adenomas with clinically nonsignificant cortisol secretion (n = 32).
METHODS: Urinary free cortisol (UFC) and 17-hydroxycorticosteroid (17OHS) were collected at baseline and during dexamethasone testing; aberrant receptor responses was also sought by clinical testing and confirmed molecularly. Peripheral and/or tumor DNA was sequenced for candidate genes.
RESULTS: AIMAH patients had the highest 17OHS excretion, even when UFCs were within or close to the normal range. Aberrant receptor expression was highly prevalent. Histology showed at least two subtypes of AIMAH. For three patients with AIMAH, there was family history of CS; germline mutations were identified in three other patients in the genes for menin (one), fumarate hydratase (one), and adenomatosis polyposis coli (APC) (one); a PDE11A gene variant was found in another. One patient had a GNAS mutation in adrenal nodules only. There were no mutations in any of the tested genes in the patients of the other groups.
CONCLUSIONS: AIMAH is a clinically and genetically heterogeneous disorder that can be associated with various genetic defects and aberrant hormone receptors. It is frequently associated with atypical CS and increased 17OHS; UFCs and other measures of adrenocortical activity can be misleadingly normal.
Bimpaki EI, Nesterova M, Stratakis CAAbnormalities of cAMP signaling are present in adrenocortical lesions associated with ACTH-independent Cushing syndrome despite the absence of mutations in known genes.
Eur J Endocrinol. 2009; 161(1):153-61 [PubMed
] Free Access to Full Article Related Publications
CONTEXT: Bilateral adrenal hyperplasias (BAHs) may be caused by mutations of genes that code for molecules that participate in cAMP signaling. Little is known about cAMP signaling in adrenal lesions associated with ACTH-independent Cushing syndrome (AICS) that do not harbor mutations in known genes.
OBJECTIVE: We assessed the cAMP-signaling pathway by enzymatic and molecular studies.
DESIGN: Samples from 27 patients (ages 5-60 years) were studied and compared with normal adrenocortical tissue (n=4) and aldosterone-producing adenomas (APA, n=5). All samples were sequenced for GNAS, PRKAR1A, PDE11A, and PDE8B sequencing defects. cAMP levels and binding, protein kinase A, and phosphodiesterase (PDE) activities were assayed. Immunohistochemistry was used for certain studies and the phosphorylation status of CREB was studied.
PATIENTS: A total of 36 samples from patients were used.
RESULTS: Cortisol-producing adenomas (CPAs) and other lesions that were GNAS, PRKAR1A, PDE11A, and PDE8B gene mutation-negative were compared with PRKAR1A mutation-positive lesions, normal tissue, and APAs; abnormalities of the cAMP-signaling pathway were found in both BAHs and CPAs. Interestingly, mutation-negative CPAs had significantly decreased PDE activity.
CONCLUSION: Lesions of the adrenal associated with AICS, independently of their GNAS, PRKAR1A, PDE11A, and PDE8B mutation status, have functional abnormalities of cAMP signaling. It is probable that epigenetic events or additional defects of genes involved in this pathway are responsible for this phenomenon.
Over the course of the last 10 years, we have studied the genetic and molecular mechanisms leading to disorders that affect the adrenal cortex, with emphasis on those that are developmental, hereditary and associated with adrenal hypoplasia or hyperplasia, multiple tumors and abnormalities in other endocrine glands. On the basis of this work, we propose an hypothesis on how adrenocortical tumors form and the importance of the cyclic AMP-dependent signaling pathway in this process. The regulatory subunit type 1-alpha (RIalpha) of protein kinase A (PKA) (the PRKAR1A gene) is mutated in most patients with Carney complex and primary pigmented nodular adrenocortical disease (PPNAD). Phosphodiesterase-11A (the PDE11A gene) and -8B (the PDE8B gene) mutations were found in patients with isolated adrenal hyperplasia and Cushing syndrome, as well in patients with PPNAD. PKA effects on tumor suppression and/or development and the cell cycle are becoming clear: PKA and/or cAMP act as a coordinator of growth and proliferation in the adrenal cortex. Mouse models in which the respective genes have been knocked out see m to support this notion. Genome-wide searches for other genes responsible for adrenal tumors and related diseases are ongoing; recent evidece of the involvement of the mitochondrial oxidation pathway in adrenocortical tumorigenesis is derived from our study of rare associations such as those of disorders predisposing to adrenomedullary and related tumors (Carney triad, the dyad of paragangliomas and gastric stromal sarcomas or Carney-Stratakis syndrome, hereditary leiomyomatosis and renal cancer syndrome) which appear to be associated with adrenocortical lesions.
PURPOSE: We have reported previously nonsense inactivating mutations of the phosphodiesterase 11A (PDE11A) gene in patients with micronodular adrenocortical hyperplasia and Cushing syndrome. The aim of this study is to investigate the presence of somatic or germ-line PDE11A mutations in various types of adrenocortical tumors: ACTH-independent macronodular adrenocortical hyperplasia (AIMAH), adrenocortical adenoma (ACA), and adrenocortical cancer (ACC).
EXPERIMENTAL DESIGN: PDE11A was sequenced in 117 adrenocortical tumors and 192 controls subjects; immunohistochemistry for PDE11A and tumor cyclic AMP levels were studied in a subgroup of adrenocortical tumors.
RESULTS: One PDE11A inactivating mutation (R307X) was found in one ACA, 22 germ-line missense variants (18.8%) were found in adrenocortical tumors, and only 11 missense variants (5.7%) were found in controls. By comparing the common mutations, a higher frequency of mutations in adrenocortical tumors than in age/sex-matched controls were observed [16% versus 10% in ACC, 19% versus 10% in ACA, and 24% versus 9% in AIMAH; odds ratio (OR), 3.53; P = 0.05]. Somatic DNA from adrenocortical tumors with missense variants showed a wild-type allelic loss. A significant difference between ACC and controls was observed for a polymorphism in exon 6 (E421E; OR, 2.1; P = 0.03) and three associated polymorphisms located in intron 10-exon 11-intron 11 (OR, 0.5; P = 0.01). In AIMAH/ACA, cyclic AMP levels were higher than in normal adrenals and decreased PDE11A immunostaining was present in adrenocortical tumors with PDE11A variants.
CONCLUSIONS: The present investigation of a large cohort of adrenocortical tumors suggests that PDE11A sequence defects predispose to a variety of lesions (beyond micronodular adrenocortical hyperplasia) and may contribute to the development of these tumors in the general population.
PURPOSE OF REVIEW: The present review discusses the molecular basis of micronodular adrenal hyperplasia. It focuses on the role of genetic defects in cyclic-AMP (cAMP) signaling-related molecules, namely PRKAR1A, GNAS, PDE11A, and PDE8B in the predisposition to tumor formation. This review also discusses the involvement of cAMP signaling and related pathways and their impact on the adrenocortical tumor formation.
RECENT FINDINGS: Molecular abnormalities in the phosphodiesterases family are the most recently discovered genetic abnormalities that predispose individuals to various adrenocortical tumors. In contrast to GNAS and PRKAR1A, defects in phosphodiesterases are associated more frequently with incomplete penetrance.
SUMMARY: Recent findings indicate the importance of cAMP signaling for normal adrenocortical functioning and the sensitivity of the adrenal gland to subtle alterations in cAMP levels. The identification of low-penetrance mutations in more than one phosphodiesterase in patients with adrenocortical hyperplasia is suggestive for a complementary role of the different phosphodiesterases in adrenal gland abnormalities and possible involvement of other members of this pathway in adrenocortical tumor defects.
Horvath A, Giatzakis C, Tsang K, et al.A cAMP-specific phosphodiesterase (PDE8B) that is mutated in adrenal hyperplasia is expressed widely in human and mouse tissues: a novel PDE8B isoform in human adrenal cortex.
Eur J Hum Genet. 2008; 16(10):1245-53 [PubMed
] Free Access to Full Article Related Publications
Bilateral adrenocortical hyperplasia (BAH) is the second most common cause of corticotropin-independent Cushing syndrome (CS). Genetic forms of BAH have been associated with complex syndromes such as Carney Complex and McCune-Albright syndrome or may present as isolated micronodular adrenocortical disease (iMAD) usually in children and young adults with CS. A genome-wide association study identified inactivating phosphodiesterase (PDE) 11A (PDE11A)-sequencing defects as low-penetrance predisposing factors for iMAD and related abnormalities; we also described a mutation (c.914A > C/H305P) in cyclic AMP (cAMP)-specific PDE8B, in a patient with iMAD. In this study we further characterize this mutation; we also found a novel PDE8B isoform that is highly expressed in the adrenal gland. This mutation is shown to significantly affect the ability of the protein to degrade cAMP in vitro. Tumor tissues from patients with iMAD and no mutations in the coding PDE8B sequence or any other related genes (PRKAR1A, PDE11A) showed downregulated PDE8B expression (compared to normal adrenal cortex). Pde8b is detectable in the adrenal gland of newborn mice and is widely expressed in other mouse tissues. We conclude that PDE8B is another PDE gene linked to iMAD; it is a candidate causative gene for other adrenocortical lesions linked to the cAMP signaling pathway and possibly for tumors in other tissues.
BACKGROUND: Primary pigmented nodular adrenocortical disease (PPNAD) leads to Cushing syndrome (CS) and is often associated with Carney complex (CNC). Genetic alterations of the type 1-alpha regulatory subunit of cAMP-dependent protein kinase A (PRKAR1A) and phosphodiesterase 11A4 (PDE11A) genes have been found in PPNAD. Recent studies have demonstrated that beta-catenin mutations are frequent in adrenocortical adenomas and carcinomas and that the Wnt-signalling pathway is involved in PPNAD tumorigenesis. We hypothesized that adrenocortical adenomas that form in the context of PPNAD may harbour beta-catenin mutations.
METHODS: We studied 18 patients with CS secondary to PPNAD who were screened for germline PRKAR1A and PDE11A mutations. Tumor DNA was extracted from pigmented adrenocortical adenoma and nodular adrenal hyperplasia. Mutation analysis of exons 3 and 5 of beta-catenin was performed using polymerase chain reaction and direct sequencing. Sections from formalin-fixed, paraffin-embedded tumour samples were studied by immunohistochemistry with an antibody against beta-catenin.
RESULTS: Nine patients were carrying germline PRKAR1A mutations and one patient had a PDE11A mutation. We found somatic beta-catenin mutations in 2 of 18 patients (11%). In both cases, the mutations occurred in relatively large adenomas that had formed in the background of PPNAD. Tumor DNA analysis revealed a heterozygous ACC-to-GCC missense mutation in codon 41 (T41A) and a TCT-to-CCT missense mutation in codon 45 (S45P) of exon 3 of the beta-catenin gene that was confirmed at the cDNA level. There were no alterations in the DNA of PPNAD-adjacent tissues and lymphocytes from the patients, indicating somatic events. Immunohistochemistry showed nuclear accumulation of beta-catenin in more than 90% of cells in adenomatous tissue whereas no nuclear immunoreactivity was detected in adjacent PPNAD nodular cells. Nuclear translocation of beta-catenin protein in the PPNAD adenoma suggests activation of the Wnt-beta-catenin pathway in PPNAD.
CONCLUSIONS: We report, for the first time, beta-catenin mutations in adenomas associated with PPNAD, further implicating Wnt-beta-catenin signalling in tumorigenesis linked to bilateral adrenal hyperplasias.
Horvath A, Stratakis CPrimary pigmented nodular adrenocortical disease and Cushing's syndrome.
Arq Bras Endocrinol Metabol. 2007; 51(8):1238-44 [PubMed
] Related Publications
Primary pigmented nodular adrenocortical disease (PPNAD) is a form of bilateral adrenocortical hyperplasia that is often associated with corticotrophin (ACTH)-independent Cushing's syndrome (CS) and is characterized by small to normal-sized adrenal glands containing multiple small cortical pigmented nodules (1,2). PPNAD may occur in an isolated form or associated with a multiple neoplasia syndrome, the complex of spotty skin pigmentation, myxomas, and endocrine overactivity, or Carney complex, in which Cushing's syndrome is the most common endocrine manifestation (3). Molecular studies have led to the identification of several genes, defects in which may predispose PPNAD formation; all of these molecules play important role for the cAMP signaling pathway. This review intends to present the most recent knowledge of the pathology and molecular genetics of the benign bilateral adrenocortical lesions, as well as to discuss the modern tools for diagnostics and treatment of this condition.
Stratakis CAAdrenocortical tumors, primary pigmented adrenocortical disease (PPNAD)/Carney complex, and other bilateral hyperplasias: the NIH studies.
Horm Metab Res. 2007; 39(6):467-73 [PubMed
] Related Publications
It has been estimated that up to 1 in 10 adults has at least one adrenocortical nodule up to 1 cm on autopsy; these benign tumors may contribute to metabolic syndrome, hypertension, obesity and abnormalities of the hypothalamic-pituitary-adrenal (HPA) axis that can be linked to other serious disorders such as osteoporosis, depression and late-onset diabetes mellitus. In addition, up to 1 in 1500 of these adrenal "incidentalomas" may hide a carcinoma, which, if diagnosed late or left untreated, is associated with significant morbidity and mortality. Consistent with the theme of this symposium, in the present report, we review the efforts undertaken at the National Institutes of Health (NIH) in the last quarter century to unravel the complex clinical genetics and molecular mechanisms involved in adrenal tumorigenesis. We first proposed that adrenocortical tumors form in a molecular sequence of events similar to that in other organs: as the pathology of the tumor increases towards malignancy, genetic changes accumulate. For example, known genetic associations, like TP53 gene changes, occur during the latest stages of adrenocortical tumorigenesis. At the NIH, significant progress has been made in the understanding of the genetics of primary pigmented adrenocortical disease (PPNAD) and other forms of bilateral adrenocortical hyperplasias. This recently led to the identification of phosphodiesterase 11A ( PDE11A) mutations as a low-penetrance predisposing factor to adrenocortical hyperplasias of both the pigmented and non-pigmented variants.