Context:
Primary macronodular adrenal hyperplasia (PMAH) is a rare cause of Cushing's syndrome, usually characterized by functioning adrenal macronodules and increased cortisol production. Familial ...clustering of PMAH has been described, suggesting an inherited genetic cause for this condition.
Objective:
The aim of the present study was to identify the gene responsible for familial PMAH.
Patients and Methods:
Forty-seven individuals of a Brazilian family with PMAH were evaluated. A single-nucleotide polymorphism-based genome-wide linkage analysis followed by whole-exome sequencing were then performed in selected family members. Additionally, 29 other patients with PMAH and 125 randomly selected healthy individuals were studied to validate the genetic findings. Moreover, PMAH tissue was also analyzed through whole-exome sequencing, conventional sequencing, and microsatellite analysis.
Results:
A heterozygous germline variant in the ARMC5 gene (p.Leu365Pro) was identified by whole-exome sequencing in a candidate genomic region (16p11.2). Subsequently, the same variant was confirmed by conventional sequencing in all 16 affected family members. The variant was predicted to be damaging by in silico methods and was not found in available online databases or in the 125 selected healthy individuals. Seven additional ARMC5 variants were subsequently identified in 5 of 21 patients with apparently sporadic PMAH and in 2 of 3 families with the disease. Further molecular analysis identified a somatic mutational event in 4 patients whose adrenal tissue was available.
Conclusions:
Inherited autosomal dominant mutations in the ARMC5 gene are a frequent cause of PMAH. Biallelic inactivation of ARMC5 is consistent with its role as a potential tumor suppressor gene.
Purpose
Pregnancy is associated with the activation of the hypothalamus–pituitary–adrenal axis, which can cause a misdiagnosis of Cushing’s syndrome. The aim of this study is to evaluate the impact ...of pregnancy after pituitary surgery on the recurrence rate in Cushing’s disease (CD) patients.
Methods
This was a retrospective study in a tertiary center. Between 1990 and 2020, 355 CD patients underwent pituitary surgery. Of those, we included 113 female patients who were ≤ 45 years old (median age of 32 years, 14–45), PS remission, a follow-up of ≥6 months (median of 122 months, 6–402) and an available obstetric history. Recurrence was defined as the diagnosis of Cushing’s syndrome via at least two altered first-line methods. The patients were divided into two subgroups according to pregnancy: no pregnancy or pregnancy prior to CD diagnosis (NP/PP) and pregnancy after CD pituitary surgery (PA).
Results
Overall, recurrence occurred in 43 out of 113 patients (38%). A higher recurrence rate was seen in the PA subgroup (11/22, 50%), but there was no significant difference between the NP/PP subgroup (32/91, 35%). No difference in survival-free recurrence (SFR) was found between NP/PP and PA subgroups. The lower SFR was related to a higher PS plasma ACTH and normal pituitary at pathological analyses.
Conclusions
There was no difference in the recurrence rate in patients according to pregnancy history. Other studies with higher numbers of patients are needed to confirm these data.
Purpose
Cushing’s disease (CD) is a severe illness generally caused by microcorticotropinomas (MICs) and in approximately 7–20% of patients by macrocorticotropinomas (MACs).
USP8
-mutations have been ...identified as a major genetic cause of CD (~ 50%). Few studies have reported the distribution between MICs–MACs related to
USP8
-mutations and their genotype–phenotype correlations. Therefore, we aimed to evaluate
USP8
-mutations in a cohort of MICs–MACs from a unique center and to perform a systematic review and meta-analysis.
Methods
DNA-tumor-tissues from 47 corticotropinomas (16 MICs and 31 MACs) were sequenced. Clinical-biochemical data, radiological imaging data and remission/recurrence rates were evaluated. In addition, we performed a meta-analysis of nine published series (n = 630).
Results
We identified four different
USP8
-mutations previously described, in 11 out of 47 (23.4%) corticotropinomas; 8 out of 11 were MACs. The urinary cortisol levels of our patients with corticotrophin
USP8
-mutated-alleles were lower than those of patients with wild-type (WT) alleles (
p
≤ 0.017). The frequency of
USP8
-mutated-alleles among the series was approximately 30% with a higher prevalence in female-patients (
p
< 0.1 × 10
−4
). Among the 5 series, the remission rates were higher in patients with
USP8
-mutated-alleles than in those with the
USP8
-WT-alleles (
p
< 0.1 × 10
−4
).
Conclusion
Our data, as well as the retrospective review of CD series associated with
USP8
-mutated alleles, show heterogeneous findings among the series. Several drawbacks included the lack of a systematic protocol to evaluate these patients before surgery and follow-up. Further prospective studies using a systematic protocol will provide more consistent information about the influence of the corticotropinomas with
USP8
-mutated alleles on the phenotype, responses to treatment and outcome of patients with CD.
ACTH-dependent hypercortisolism caused by a pituitary adenoma Cushing's disease (CD) is the most common cause of endogenous Cushing's syndrome. CD is often associated with several morbidities, ...including hypertension, diabetes, osteoporosis/bone fractures, secondary infections, and increased cardiovascular mortality. While the majority (≈80%) of the corticotrophinomas visible on pituitary magnetic resonance imaging are microadenomas (MICs, <10 mm of diameter), some tumors are macroadenomas (MACs, ≥10 mm) with increased growth potential and invasiveness, exceptionally exhibiting malignant demeanor. In addition, larger and invasive MACs are associated with a significant increased risk of local complications, such as hypopituitarism and visual defects. Given the clinical and molecular heterogeneity of corticotrophinomas, the aim of this study was to investigate the pattern of genetic differential expression between MIC and MAC, including the invasiveness grade as a criterion for categorizing these tumors. In this study, were included tumor samples from patients with clinical, laboratorial, radiological, and histopathological diagnosis of hypercortisolism due to an ACTH-producing pituitary adenoma. Differential gene expression was studied using an Affymetrix microarray platform in 12 corticotrophinomas, classified as non-invasive MIC (
= 4) and MAC (
= 5), and invasive MAC (
= 3), according to modified Hardy criteria. Somatic mutations in
were also investigated, but none of the patients exhibited
variants. Differential expression analysis demonstrated that non-invasive MIC and MAC have a similar genetic signature, while invasive MACs exhibited a differential expression profile. Among the genes differentially expressed, we highlighted
, and
, and their differential expression was validated through quantitative real-time PCR in another cohort of 15 non-invasive and 3 invasive cortocotrophinomas. We also identified potential biological pathways associated with growth and invasiveness, TGF-β and G protein signaling pathways, DNA damage response pathway, and pathways associated with focal adhesion. Our study revealed a differential pattern of genetic signature in a subgroup of MAC, supporting a genetic influence on corticotrophinomas in patients with CD.
Neural tube defects (NTDs) are caused by genetic and environmental factors. ARMC5 is part of a novel ubiquitin ligase specific for POLR2A, the largest subunit of RNA polymerase II (Pol II).
We find ...that ARMC5 knockout mice have increased incidence of NTDs, such as spina bifida and exencephaly. Surprisingly, the absence of ARMC5 causes the accumulation of not only POLR2A but also most of the other 11 Pol II subunits, indicating that the degradation of the whole Pol II complex is compromised. The enlarged Pol II pool does not lead to generalized Pol II stalling or a generalized decrease in mRNA transcription. In neural progenitor cells, ARMC5 knockout only dysregulates 106 genes, some of which are known to be involved in neural tube development. FOLH1, critical in folate uptake and hence neural tube development, is downregulated in the knockout intestine. We also identify nine deleterious mutations in the ARMC5 gene in 511 patients with myelomeningocele, a severe form of spina bifida. These mutations impair the interaction between ARMC5 and Pol II and reduce Pol II ubiquitination.
Mutations in ARMC5 increase the risk of NTDs in mice and humans. ARMC5 is part of an E3 controlling the degradation of all 12 subunits of Pol II under physiological conditions. The Pol II pool size might have effects on NTD pathogenesis, and some of the effects might be via the downregulation of FOLH1. Additional mechanistic work is needed to establish the causal effect of the findings on NTD pathogenesis.
The risk of radiotherapy-induced malignancies (RIMs) is a concern when treating Li–Fraumeni syndrome (LFS) or Li–Fraumeni Like (LFL) patients. However, the type of
TP53
pathogenic germline variant ...may possibly influence this risk.
TP53
p.R337H mutation is particularly prevalent in Brazil. We aimed to evaluate the outcomes of patients with pathogenic
TP53
variants treated for localized breast cancer in a Brazilian cohort. We evaluated retrospectively a cohort of patients with germline
TP53
pathogenic variants treated for localized breast cancer between December 1999 and October 2017. All patients were followed by the Hereditary Cancer Group of an academic cancer center. Our primary objective was to evaluate the occurrence of RIMs after adjuvant radiotherapy. Sixteen patients were evaluated; 10 (62.5%) had a germline
TP53
p.R337H pathogenic variant. Median age was 39.8 years. Thirteen patients had invasive ductal carcinoma: 8 (61.5%) were hormone receptor-positive; 6 (46.1%), human epithelial growth factor receptor 2 (HER2)-amplified. Three patients had ductal carcinoma in situ. Most patients (N = 12/16, 75%) received adjuvant radiotherapy. After a median follow-up of 52.5 months, 2 patients (2/12, 16.6%) had RIMs. One had a fibrosarcoma and the other, a low-grade leiomyosarcoma. In the group treated with radiotherapy, one distant recurrence was diagnosed (1/12), and no loco-regional recurrence occurred. Among 4 patients who did not receive radiotherapy, 2 presented with loco-regional recurrence. In this cohort of patients with LFS enriched in
TP53
p.R337H pathogenic variant, the incidence of RIMs after treatment of localized breast cancer was lower than previous literature. Nevertheless, rates of RIMs were still alarming. Early molecular diagnosis and careful evaluation of treatment risks and benefits are essential for these patients.
Adrenocortical carcinoma (ACC) is an aggressive endocrine cancer with few molecular predictors of malignancy and survival, especially in paediatric patients. Stathmin 1 (STMN1) regulates microtubule ...dynamics and has been involved in the malignant phenotype of cancer cells. Recently, it was reported that STMN1 is highly expressed in ACC patients, and STMN1 silencing reduces the clonogenicity and migration of ACC cell lines. However, the prognostic significance of STMN1 and its therapeutic potential remain undefined in ACC. In the present study,
STMN1
mRNA levels were significantly higher (
p
< 0.05) in ACC patients, especially in an advanced stage, and correlated with
BUB1B
and
PINK1
expression, the prognostic-related genes in ACC. In paediatric tumours, high
STMN1
expression was observed in both adrenocortical carcinoma and adrenocortical adenoma patients. Among the adult malignant tumours,
STMN1
level was an independent predictor of survival outcomes (overall survival: hazard ratio = 6.08,
p
= 0.002; disease-free survival: hazard ratio = 4.65,
p
< 0.0001). Paclitaxel, a microtubule-stabilizing drug, reduces the activation of STMN1 and significantly decreases cell migration and invasion in ACC cell lines and ACC cells from secondary cell culture (all
p
< 0.0001). In summary, STMN1 expression may be of great value to clinical and pathological findings in therapeutic trials and deserves future studies in ACC.
•The TP53 p.R337H mutation is highly prevalent among children with adrenocortical tumor from South and Southeast Brazil•Other tumors of the LFS/LFL spectrum are seen in patients exhibiting this ...mutation, however, the occurrence of multiple tumors is rare.•There is a large difference in the aggressiveness of adrenocortical tumors depending on the age group in which these tumors are diagnosed.•In this specific population, the maternal inheritance of the mutated allele was predominant.
The TP53 p.R337H germline mutation is highly prevalent among children with adrenocortical tumors (ACTs) from South and Southeast Brazil. However, the prevalence of other tumors of the Li-Fraumeni syndrome (LFS) and Li-Fraumeni-like syndrome (LFL) spectrum, the clinical outcomes and the potential tumor occurrence in relatives carrying this distinct TP53 mutation were not fully investigated.
We investigated tumor profile data and outcomes of individuals and their close relatives with the TP53 p.R337H germline mutation. A questionnaire and the Toronto protocol were used for evaluation of asymptomatic carriers of this TP53 mutation.
The cohort of this study comprised 51 patients from 46 different families; 67% were female. All but one harbored the TP53 p.R337H mutation in heterozygous state; only one child was homozygous for this variant. Maternal allele inheritance occurred in 72% of the cases (p= 0,002). In pediatric group, ACT was the most common primary tumor at the diagnosis (55%; median age= 2 years). No patient of the pediatric group who initially presented with ACT developed a second primary tumor and 11% (n= 3) died due to complications related to the primary tumor (median follow-up time of 81.5 months, range= 3-378 months). In adult group, the main tumors at diagnosis were: adrenocortical carcinoma (ACC) (23%; median age= 29.5 years), breast cancer (12%; median age= 38.5 years), soft tissue sarcoma (8%; median age= 50.3 years) and choroid plexus carcinoma (CPC) (2%; median age= 18 years). Among adult patients who were diagnosed with ACC as the first primary tumor, all presented with aggressive disease as per histologic and clinical criteria at diagnosis, and 75% of patients died (median follow-up time of 19 months, range= 1-69 months). Five adult patients (22%) had a second primary tumor, including bronchoalveolar lung cancer (2 cases), ACC, uterine cervical carcinoma and fibrosarcoma. The diagnosis of these tumors was established from 8 to 36 months after the first primary tumor. Three families presented more than one case of ACT. Nine malignant neoplasms were diagnosed in asymptomatic carriers using Toronto protocol.
This study confirms a high frequency of TP53 p.R337H mutation in pediatric group with ACT. In addition, we observed the occurrence of other tumors of LFS/LFL spectrum and a difference in the aggressiveness of ACTs depending on the age group in which they were diagnosed. The predominance of maternal mutated allele inheritance was first demonstrated in the affected Brazilian’s families.
Background: Adrenocortical tumors are heterogeneous neoplasms with incompletely understood pathogenesis. IGF-II overexpression has been consistently demonstrated in adult adrenocortical carcinomas.
...Objectives: The objective of the study was to analyze expression of IGF-II and its receptor (IGF-IR) in pediatric and adult adrenocortical tumors and the effects of a selective IGF-IR kinase inhibitor (NVP-AEW541) on adrenocortical tumor cells.
Patients: Fifty-seven adrenocortical tumors (37 adenomas and 20 carcinomas) from 23 children and 34 adults were studied.
Methods: Gene expression was determined by quantitative real-time PCR. Cell proliferation and apoptosis were analyzed in NCI H295 cells and a new cell line established from a pediatric adrenocortical adenoma.
Results: IGF-II transcripts were overexpressed in both pediatric adrenocortical carcinomas and adenomas. Otherwise, IGF-II was mainly overexpressed in adult adrenocortical carcinomas (270.5 ± 130.2 vs. 16.1 ± 13.3; P = 0.0001). IGF-IR expression was significantly higher in pediatric adrenocortical carcinomas than adenomas (9.1 ± 3.1 vs. 2.6 ± 0.3; P = 0.0001), whereas its expression was similar in adult adrenocortical carcinomas and adenomas. IGF-IR expression was a predictor of metastases in pediatric adrenocortical tumors in univariate analysis (hazard ratio 1.84; 95% confidence interval 1.28–2.66; P = 0.01). Furthermore, NVP-AEW541 blocked cell proliferation in a dose- and time-dependent manner in both cell lines through a significant increase of apoptosis.
Conclusion: IGF-IR overexpression was a biomarker of pediatric adrenocortical carcinomas. Additionally, a selective IGF-IR kinase inhibitor had antitumor effects in adult and pediatric adrenocortical tumor cell lines, suggesting that IGF-IR inhibitors represent a promising therapy for human adrenocortical carcinoma.
ARMC5 (Armadillo repeat containing 5 gene) was identified as a new tumor suppressor gene responsible for hereditary adrenocortical tumors and meningiomas. ARMC5 is ubiquitously expressed and encodes ...a protein which contains a N-terminal Armadillo repeat domain and a C-terminal BTB (Bric-a-Brac, Tramtrack and Broad-complex) domain, both docking platforms for numerous proteins. At present, expression regulation and mechanisms of action of ARMC5 are almost unknown. In this study, we showed that ARMC5 interacts with CUL3 requiring its BTB domain. This interaction leads to ARMC5 ubiquitination and further degradation by the proteasome. ARMC5 alters cell cycle (G1/S phases and cyclin E accumulation) and this effect is blocked by CUL3. Moreover, missense mutants in the BTB domain of ARMC5, identified in patients with multiple adrenocortical tumors, are neither able to interact and be degraded by CUL3/proteasome nor alter cell cycle. These data show a new mechanism of regulation of the ARMC5 protein and open new perspectives in the understanding of its tumor suppressor activity.
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