Adrenal cysts of lymphatic origin: A clinical and pathological study of six cases and systematic literature review.

Adrenal cysts are rare, benign, and usually asymptomatic, being detected as an incidental finding on imaging methods. Adrenal Cysts of Lymphatic Origin (ACLO) and Adrenal Lymphangiomas (AL) are types of endothelial cyst and are the most prevalent subtype in this series. This study aims to present a single institutional experience of these rare cysts and compare their features with those found in the review of existing literature on ACLO and AL. Overall, thirteen cases of adrenal cysts were diagnosed and surgically excised during the study period, onto which we performed immunohistochemistry using a panel of antibodies (CD31, CD34, Pan Cytokeratin AE-1/AE-3, Factor VII, D2-40, and ERG). Four cases of ACLO and two AL were found. The lesions predominantly affected right adrenal, and the majority of patients were middle-age females, of Caucasian ethnicity, and asymptomatic. In our literature review, we found 108 cases of ACLO/AL from 57 articles with similar sex and age distribution. The diagnosis and subclassification of adrenal cysts are challenging, and there is a significant overlapping between the definition of ACLO and AL.

Low Protein Expression of both ATRX and ZNRF3 as Novel Negative Prognostic Markers of Adult Adrenocortical Carcinoma.

Adrenocortical carcinoma (ACC) is a rare malignancy that is associated with a dismal prognosis. Pan-genomic studies have demonstrated the involvement of ATRX and ZNRF3 genes in adrenocortical tumorigenesis. Our aims were to evaluate the protein expression of ATRX and ZNRF3 in a cohort of 82 adults with ACC and to establish their prognostic value. Two pathologists analyzed immuno-stained slides of a tissue microarray. The low protein expression of ATRX and ZNRF3 was associated with a decrease in overall survival (OS) (p = 0.045, p = 0.012, respectively). The Cox regression for ATRX protein expression of >1.5 showed a hazard ratio (HR) for OS of 0.521 (95% CI 0.273-0.997; p = 0.049) when compared with ≤1.5; for ZNRF3 expression >2, the HR for OS was 0.441 (95% CI, 0.229-0.852; p = 0.015) when compared with ≤2. High ATRX and ZNRF3 protein expressions were associated with optimistic recurrence-free survival (RFS) (p = 0.027 and p = 0.005, respectively). The Cox regression of RFS showed an HR of 0.332 (95%CI, 0.111-0.932) for ATRX expression >2.7 (p = 0.037), and an HR of 0.333 (95%CI, 0.140-0.790) for ZNRF3 expression >2 (p = 0.013). In conclusion, low protein expression of ATRX and ZNRF3 are negative prognostic markers of ACC; however, different cohorts should be evaluated to validate these findings.

Stathmin 1 is highly expressed and associated with survival outcome in malignant adrenocortical tumours.

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.

Absolute monocyte count is a predictor of overall survival and progression-free survival in nodal peripheral T cell lymphoma.

Nodal peripheral T cell lymphomas (nPTCL) present aggressive clinical course, and its heterogeneous nature and poor prognosis with current therapeutic strategies make it a target for the development of new prognostic markers. Thus, we investigated tumor-associated macrophages (TAM) according to the number of cells expressing CD68 in biopsies and the absolute monocyte count (AMC) in peripheral blood of 87 patients with nPTCL. The median overall survival (OS) was 3 years (95% CI 1.3-8.4 years) and estimate 5 years OS of 43.3% (95% CI 32.5-53.7%). The median progression-free survival (PFS) was 1.5 years (95% CI 0.8-2.6 years) with estimate 5 years PFS of 29.2% (95% CI 19.7-39.3%). The cutoff for AMC was 1.5 × 109/L and the median OS for patients with AMC ≥ 1.5 × 109/L was 0.83 years versus 3.7 years for those with AMC < 1.5 × 109/L (HR 2.32, 95% CI 1.03-5.22, p = 0.035). The median PFS for patients with AMC ≥ 1.5 × 109/L was 0.50 years versus 1.5 years for those with AMC < 1.5 × 109/L (HR 2.25, 95% CI 1.05-4.78, p = 0.031). CD68 was evaluated in 26/87 (29.8%) patients with a median expression of 34% and positivity cutoff of 43%. CD68 expression was not associated with OS or PFS either with AMC values. Our findings suggest that the AMC of ≥ 1.5 × 109/L at diagnosis in peripheral blood is associated with poor prognosis in nPTCL. Further investigations in a larger cohort are required to better validate our results.

Differential Expression of Stem Cell Markers in Human Adamantinomatous Craniopharyngioma and Pituitary Adenoma.

BACKGROUND/AIMS: Although craniopharyngioma (CP) is histologically benign, it is a pituitary tumour that grows rapidly and often recurs. Adamantinomatous CP (ACP) was associated with an activating mutation in ß-catenin, and it has been postulated that pituitary stem cells might play a role in oncogenesis in human ACP. Stem cells have also been identified in pituitary adenoma. Our aim was to characterize the expression pattern of ABCG2, CD44, DLL4, NANOG, NOTCH2, POU5F1/OCT4, SOX2, and SOX9 stem cell markers in human ACP and pituitary adenoma. METHODS AND RESULTS: We studied 33 patients (9 ACP and 24 adenoma) using real-time quantitative PCR (RT-qPCR) and immunohistochemistry. SOX9 was up-regulated in ACP, exhibiting positive immunostaining in the epithelium and stroma, with the highest expression in patients with recurrence. CD44 was overexpressed in ACP as confirmed by immunohistochemistry. SOX2 did not significantly differ among the tumour types. The RT-qPCR array showed an increased expression of MKI67,OCT4/POU5F1, and DLL4 in all tumours. NANOG was decreased in ACP. ABCG2 was down-regulated in most of the tumours. NOTCH2 was significantly decreased in the adenomas. CONCLUSION: Our results confirm the presence of stem cell markers in human pituitary tumours as well as the different expression patterns of ACP and adenoma. These findings suggest that ACP may originate from a more undifferentiated cell cluster. Additionally, SOX9 immunodetection in the stroma and the highest expression levels related to the relapse of patients suggest a contribution to the aggressive behaviour and high recurrence of this tumour type.

High 18F-FDG uptake in PMAH correlated with normal expression of Glut1, HK1, HK2, and HK3.

BACKGROUND: Primary macronodular adrenal hyperplasia (PMAH) is a rare cause of Cushing's syndrome, characterized by functioning adrenal macronodules and variable cortisol production. Recently, we demonstrated a high 18F-FDG uptake in PMAH, an unexpected finding for a benign disorder. PURPOSE: To investigate whether there is a correlation between 18F-FDG high uptake and the expression levels of the glycolytic pathway components GLUT1, HK1, HK2, and HK3 in PMAH. MATERIAL AND METHODS: We selected 12 patients undergoing surgery for PMAH who had preoperatively undergone 18F-FDG PET/CT. mRNA and protein expression of the selected genes were evaluated in the adrenal nodules from patients who underwent surgery through quantitative RT-PCR and by immunohistochemistry, respectively. RESULTS: SUVmax in PMAH was in the range of 3.3-8.9 and the adrenal size was in the range of 3.5-15 cm. A strong correlation between 18F-FDG uptake and largest adrenal diameter was observed in patients with PMAH. However, no correlation between 18F-FDG uptake and GLUT1, HK1, HK2, HK3 mRNA, and protein expression was observed. CONCLUSION: High 18F-FDG uptake is observed in the majority of PMAH cases. However, 18F-FDG uptake in PMAH is independent of the expression levels of GLUT1, HK1, HK2, and HK3. Further investigation is required to elucidate the molecular mechanisms underlying increased 18F-FDG uptake in PMAH.

Evaluation of the 2008 World Health Organization classification for non-mycosis fungoides, non-Sezary syndrome T/NK-cell lymphomas with primary cutaneous involvement.

BACKGROUND: Cutaneous non-mycosis fungoides non-Sezary syndrome T/NK cell lymphomas (non-MF/non-SS CTCL) are rare. In 2005, a consensus of the World Health Organization (WHO) and European Organization for Research and Treatment of Cancer (EORTC) classifications for primary cutaneous lymphomas was established. These guidelines were then adopted into the WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues, 2008. This study aims to assess the applicability of the WHO 2008 classification in a retrospective series of CTCL cases registered in a reference academic center in Brazil. METHODS: Twenty-seven patients with non-MF/non-SS CTCL were studied. Clinical, histopathological and immunophenotypical features based on an extensive panel of antibodies were applied to classify the cases according to the WHO, 2008. RESULTS: Overall, diagnostic categories included eight (29.6%) cutaneous anaplastic large-cell lymphoma, five (18.5%) lymphomatoid papulosis, six (22.2%) extranodal natural killer (NK)/T-cell lymphoma, nasal type, five (18.5%) adult T-cell leukemia/lymphoma, one (3.7%) cutaneous CD8-positive aggressive epidermotropic cytotoxic T-cell lymphoma and two (7.4%) of peripheral T-cell lymphoma not otherwise specified (NOS). CONCLUSIONS: The WHO classification (2008) was applicable to most cases of non-MF/non-SS CTCL, while some cases remained unclassified and were considered NOS-peripheral T-cell lymphoma. An unexpected high frequency of NK/T-cell lymphoma nasal type was observed.

Development and internal validation of an adrenal cortical carcinoma prognostic score for predicting the risk of metastasis and local recurrence.

OBJECTIVE: To develop and internally validate a prognostic score to predict the risk of metastases or recurrence in patients with adrenal cortical carcinomas (ACC). DESIGN: Clinical, laboratory and pathological data from 129 ACC patients, treated in a tertiary centre, were retrospectively reviewed. RESULTS: Using a multivariate binary logistic regression analysis, we developed a prognostic score with five covariates: a functional pattern other than isolated hyperandrogenism, a tumour size >7·5 cm, a primary tumour classified as T3/T4, the presence of microscopic venous invasion and a mitotic index >5/50 high-power fields. The prognostic score was calibrated according to the Hosmer-Lemeshow goodness-of-fit test (P = 0·9329) and exhibited excellent overall performance (Brier score = 0·0738). Finally, the discriminatory ability of the model, determined by the area under the ROC curve (AROC ), was near perfect (AROC , 0·9611; 95% CI, 0·92676-0·99552). The prediction model was internally validated with 200 bootstrap resamples and achieved excellent performance for estimating the risk of metastasis and recurrence in eight additional patients with apparently localized disease at diagnosis. CONCLUSION: We developed and internally validated a prognostic score based on the clinicopathological data that are readily available to any attending physician. Our model can be used to accurately estimate the risk of unfavourable outcomes in ACC patients. This score could be beneficial for both patient counselling and the identification of patients in whom adjuvant mitotane is justified.

Morphological Harbingers of ARMC5-Pathogenic Variant-Related Bilateral Macronodular Adrenocortical Disease.

Bilateral macronodular adrenocortical disease (BMAD) is a neoplastic disease associated with a high frequency of germline disease. Armadillo repeat containing 5 (ARMC5) pathogenic variants (PVs) have not been widely studied to determine the morphological and immunohistochemical characteristics of BMAD. We carried out a detailed morphologic review of 22 surgical specimens excised from patients with BMAD and compared them with PV of ARMC5 (PV + , n = 14) and those without (PV - , n = 8), and further comparing them with a control group of adrenals excised from patients with renal cancer (n = 11). No patients presented with a genetic syndrome related to BMAD. Overt Cushing's syndrome was present in 12/22 patients, 10 PV + and 2 PV - (p = 0.074). We also evaluated the expression of Ki-67, BCL-2, BAX, p53, CYP11B1, and ARMC5 protein. The pseudo-glandular and trabecular architectural patterns were strongly associated with the PV + group (both p < 0.001), as well as capsular extrusion (p < 0.001). There was no predictive value in the distinction of ARMC5 variants in Hsiao subtyping. ARMC5 diffuse cytoplasmic staining was observed in all 11 control samples. The ARMC5 expression was significantly lower in BMAD than in the control group (p < 0.001). In all the specimens, expression of BCL-2 was identified only in the medulla, and expression of BAX was observed in adrenocortical cells. CYP11B1 diffuse immunoexpression was identified in all the specimens of BMAD and in the fasciculata zone in the control group. The mitotic count and Ki-67 proliferation index was very low in all three groups (controls, PV + , and PV - BMAD). None of the specimens stained positive for the p53 protein. Although our series is limited, the presence of pseudo-glandular and/or trabecular patterns and capsular extrusion indicated the presence of pathogenic variants of ARMC5 in BMAD. The gland enlargement does not seem to be related to the increase of mitotic count or a higher proliferation index (Ki-67).

Up-front Therapy With CHOP Plus Etoposide in Brazilian nodal PTCL Patients: Increased Toxicity and No Survival Benefit Compared to CHOP Regimen-Results of a Real-Life Study From a Middle-Income Country.

BACKGROUND: Nodal peripheral T-cell lymphoma (nPTCL) constitute a heterogeneous group of neoplasms with aggressive behavior and poor-survival. They are more prevalent in Latin America and Asia, although data from Brazil are scarce. Its primary therapy is still controversial and ineffective. Therefore, we aim to describe clinical-epidemiological characteristics, outcomes, predictors factors for survival and compare the results of patients treated with CHOP and CHOEP regimens. METHODS: Retrospective, observational and single-center study involving 124 nPTCL patients from Brazil treated from 2000 to 2019. RESULTS: With a median follow-up of 23.7 months, the estimated 2-year overall survival (OS) and progression-free survival (PFS) were 59.2% and 37.3%, respectively. The median age was 48.5 years and 57.3% (71/124) were male, 81.5% (101/124) had B-symptoms, 88.7% (110/124) had advanced disease (stage III/IV) and 58.1% (72/124) presented International Prognostic Index (IPI) score ≥3, reflecting a real-life cohort. ORR to first-line therapy was 58.9%, 37.9% (N = 47) received CHOP-21 and 35.5% (N = 44) were treated with CHOEP-21; 30.1% (37/124) underwent to consolidation with involved field radiotherapy (IF-RT) and 32.3% (40/124) were consolidated with autologous hematopoietic stem cell transplantation (ASCT). The overall response rate (ORR) was similar for CHOP-21 (76.6%) and CHOEP-21 (65.9%), P = .259. Refractory disease was less frequent in the CHOEP-21 group (4.5% vs. 21.2%, P = .018). However, few patients were able to complete 6-cycles of CHOEP-21 (31.8%) than to CHOP-21 (61.7%), P = .003. Delays ≥2 weeks among the cycles of chemotherapy were more frequent for patients receiving CHOEP-21 (43.1% vs. 10.6%), P = .0004, as well as the toxicities, including G3-4 neutropenia (88% vs. 57%, P = .001), febrile neutropenia (70% vs. 38%, P = .003) and G3-4 thrombocytopenia (63% vs. 27%, P = .0007). The 2-year OS was higher for CHOP (78.7%) than CHOEP group (61.4%), P = .05, as well as 2-year PFS (69.7% vs. 25.0%, P < .0001). In multivariate analysis, high LDH (HR 3.38, P = .007) was associated with decreased OS. CR at first line (HR: 0.09, P < .001) and consolidation with ASCT (HR: 0.08, P = .015) were predictors of increased OS. CONCLUSION: In the largest cohort of nPTCL from Latin America, patients had poor survival and high rate of chemo-resistance. In our cohort, the addition of etoposide to the CHOP-21 backbone showed no survival benefit and was associated with high-toxicity and frequent treatment interruptions. Normal LDH values, obtaintion of CR and consolidation with ASCT were independent factors associated with better outcomes.

TET-2 mutations predict poor outcomes and are associated with unfavorable clinical-biological features in PTCL, not otherwise specified and angioimmunoblastic T-cell lymphoma in Brazilian patients.

INTRODUCTION: Nodal peripheral T-cell lymphomas [nPTCL] constitute a heterogeneous group of rare malignancies with aggressive biological behavior and poor prognosis. Epigenetic phenomena involving genes that control DNA-methylation and histone deacetylation play a central role in their pathogenesis. However, the mutational landscape involving epigenetic regulators has never been reported in Latin American patients and their prognostic impact remains controversial. PATIENTS AND METHODS: From 2000 to 2019, 59-Brazilian patients with nPTCL were eligible for screening mutations in the IDH-1, IDH-2, RHOA, TET-2 and DNMT3A genes by Sanger sequencing at Formalin-Fixed Paraffin-Embedded samples [FFPE] of diagnosis. We reported the frequency, distribution and potential prognosis of these mutations. RESULTS: With a median follow-up of 3.70 years, estimate 2-year OS and PFS were 57.1% and 49.2%, respectively. Mutations in the IDH-1 gene were not found, mutations in the IDH-2 occurred in 3.4% (2/59), RHOA in 23.7% (14/59), TET-2 in 50.8% (30/59) and DNMT3A in 62.7% (37/59). RHOA gene mutations were more frequent in PTCL, NOS and AITL (p= 0.06). Almost half of the patients had more than one mutation in concomitance, particularly RHOA-mut and TET-2-mut. Mutations in RHOA (p= 0.030) and TET-2 (p= 0.046) were associated with high-tumor burden. In the non-ALCL subgroup (PTCL, NOS and AITL) TET-2 mutations were associated with decreased 2-year PFS [HR: 2.22, p= 0.048]. Likewise with lower overall response rate [ORR] (p= 0.048) and unfavorable clinical features, as bulky disease (p= 0.012), ECOG ⩾ 2 (p= 0.032), B-symptoms (p= 0.012), ⩾ 2 extranodal sites compromised (p= 0.022) and high-risk Prognostic Index for T-cell lymphoma (p= 0.005). CONCLUSION: Mutations in RHOA, TET-2 and DNMT3A were frequent in Brazilian patients with nPTCL. TET-2 mutations were associated with lower ORR for CHOP-like chemotherapy, decreased PFS and unfavorable clinical-biological characteristics in non-ALCL (PTCL, NOS and AITL). Further studies using a larger cohort may validate our findings.

The role of whole-brain radiotherapy (WBRT) in primary central nervous system lymphoma: is it an alternative to ASCT for consolidation following HD-methotrexate based induction in low-income settings?

BACKGROUND: Primary central nervous system lymphoma (PCNSL) is a rare and aggressive malignancy. Although potentially curable, its prognosis remains dismal. Its treatment is based on high-doses of methotrexate (HD-MTX) and rituximab, followed by consolidation therapy with whole-brain radiotherapy (WBRT) or autologous stem cell transplantation (ASCT). Currently, there is no consensus about the best consolidation strategy, but better outcomes with ASCT are obtained with conditioning regimens based on thiotepa, a high-cost drug with restricted use in resource-constrained settings. Latin American data on clinical outcomes, prognostic factors, and therapeutic management in PCNSL are virtually unknown. METHODS: This is a retrospective, observational, and single-center study involving 47-Brazilian patients with PCNSL. We aim to assess outcomes, determine predictors of survival, and compare responses, as well as toxicities in patients consolidated with chemotherapy alone versus chemotherapy plus WBRT. RESULTS: The median age at diagnosis was 59 years (24-88 years), and 53.1% were male. LDH ≥ UVN occurred in 44.7%, ECOG ≥ 2 in 67.6%, and 34.1% had multifocal disease. Hemiparesis was the main clinical presentation, observed in 55.3%, 51.0% had intermediate-/high-risk IELSG prognostic score, and 57.6% had an ABC-like phenotype by IHC. With a median follow-up of 24.4 months, estimated 5-year OS and PFS were 45.5% and 36.4%, respectively. Among 40 patients treated with HD-MTX-based induction, estimated 2-year OS was 85.8% for those consolidated with WBRT plus HIDAC versus only 41.5% for those consolidated with HIDAC alone (p < 0.001). Hematologic and non-hematologic toxicities were not significant, and severe cognitive impairment occurred in only 6.3% (3/47) of cases, all of them treated with WBRT. Age < 60 years, Hb ≥ 120 g/L and WBRT consolidation were associated with increased OS, however, LDH ≥ UVN, hypoalbuminemia, ECOG ≥ 2, Karnofsky PS < 70 and intermediate-/high-risk Barcelona score were associated with decreased OS. CONCLUSION: Combined consolidation therapy (CCT) based on WBRT plus HIDAC was associated with increased OS in PCNSL compared to isolated consolidation therapy (ICT) based on HIDAC alone. Here, severe late neurotoxicity was uncommon with this approach. These data suggest that WBRT may be an effective and safe alternative to ASCT for consolidation therapy in PCNSL, particularly in resource-constrained settings, where access to thiotepa for pre-ASCT conditioning is not universal.

International Histopathology Consensus for Unilateral Primary Aldosteronism.

OBJECTIVE: Develop a consensus for the nomenclature and definition of adrenal histopathologic features in unilateral primary aldosteronism (PA). CONTEXT: Unilateral PA is the most common surgically treated form of hypertension. Morphologic examination combined with CYP11B2 (aldosterone synthase) immunostaining reveals diverse histopathologic features of lesions in the resected adrenals. PATIENTS AND METHODS: Surgically removed adrenals (n = 37) from 90 patients operated from 2015 to 2018 in Munich, Germany, were selected to represent the broad histologic spectrum of unilateral PA. Five pathologists (Group 1 from Germany, Italy, and Japan) evaluated the histopathology of hematoxylin-eosin (HE) and CYP11B2 immunostained sections, and a consensus was established to define the identifiable features. The consensus was subsequently used by 6 additional pathologists (Group 2 from Australia, Brazil, Canada, Japan, United Kingdom, United States) for the assessment of all adrenals with disagreement for histopathologic diagnoses among group 1 pathologists. RESULTS: Consensus was achieved to define histopathologic features associated with PA. Use of CYP11B2 immunostaining resulted in a change of the original HE morphology-driven diagnosis in 5 (14%) of 37 cases. Using the consensus criteria, group 2 pathologists agreed for the evaluation of 11 of the 12 cases of disagreement among group 1 pathologists. CONCLUSION: The HISTALDO (histopathology of primary aldosteronism) consensus is useful to standardize nomenclature and achieve consistency among pathologists for the histopathologic diagnosis of unilateral PA. CYP11B2 immunohistochemistry should be incorporated into the routine clinical diagnostic workup to localize the likely source of aldosterone production.

Medical students with performance difficulties need wide support: Initial results of an academic tutoring program.

BACKGROUND: Even students with previous academic success may face challenges that affect their academic performance. Many medical schools offer programs to students at the risk of academic failure, to ensure that they succeed in the course. OBJECTIVE AND METHODS: In this report we describe a pioneering academic tutoring program developed at a Brazilian medical school and discuss the initial results of the program based on the feedback from tutors and data regarding the progression of students in the medical course. RESULTS: In 2018, 33 students enrolled into the program. Students' performance difficulties were mainly associated with mental health problems and socioeconomic vulnerability. Of the 33 students, 27 (81.8%) were assisted by the Mental Health Support Service and 16 (48.5%) were assisted by the Social Assistance Service. In addition to the planning academic activity class load, tutors were able to assist students in solving socioeconomic issues, carrying out personal support interventions with the promotion of self-esteem, and presenting suggestions for behavioral changes in their routine. For most students (72%), the action plan proposed by the tutors was successful. Eight of the 14 (57%) students in the fourth year progressed to the final two years of in-hospital practical training (internship). CONCLUSIONS: The Academic Tutoring Program showed positive results for most of the students. Close monitoring and tutor intervention allowed students with poor academic performance to overcome the low performance cycle. These important tasks demand time and energy from tutors, and institutional recognition of these professionals is essential for the successful maintenance of the program.

Age-related transcriptional modules and TF-miRNA-mRNA interactions in neonatal and infant human thymus.

The human thymus suffers a transient neonatal involution, recovers and then starts a process of decline between the 1st and 2nd years of life. Age-related morphological changes in thymus were extensively investigated, but the genomic mechanisms underlying this process remain largely unknown. Through Weighted Gene Co-expression Network Analysis (WGCNA) and TF-miRNA-mRNA integrative analysis we studied the transcriptome of neonate and infant thymic tissues grouped by age: 0-30 days (A); 31days-6 months (B); 7-12 months (C); 13-18 months (D); 19-31months (E). Age-related transcriptional modules, hubs and high gene significance (HGS) genes were identified, as well as TF-miRNA-hub/HGS co-expression correlations. Three transcriptional modules were correlated with A and/or E groups. Hubs were mostly related to cellular/metabolic processes; few were differentially expressed (DE) or related to T-cell development. Inversely, HGS genes in groups A and E were mostly DE. In A (neonate) one third of the hyper-expressed HGS genes were related to T-cell development, against one-twentieth in E, what may correlate with the early neonatal depletion and recovery of thymic T-cell populations. This genomic mechanism is tightly regulated by TF-miRNA-hub/HGS interactions that differentially govern cellular and molecular processes involved in the functioning of the neonate thymus and in the beginning of thymic decline.

ARMC5 mutations are associated with high levels of proliferating cell nuclear antigen and the presence of the serotonin receptor 5HT4R in PMAH nodules.

Objective To analyze the morphological and functional characteristics of primary macronodular adrenal hyperplasia (PMAH) nodules carrying or not carrying ARMC5 mutations and the consequences of the presence of mutations in terms of the pattern of macronodule composition and functional state. Subjects and methods The analyses were performed by hematoxylin-eosin staining, immunohistochemistry, microdissection of spongiocyte tissue and RT-qPCR of histological sections from 16 patients diagnosed with PMAH with germline (5) or germline/somatic mutations (5) and without mutations (6) in the ARMC5 gene. Results Hyperplastic nodules were predominantly composed of spongiocytes in mutated and nonmutated sections. ARMC5 mRNA expression in spongiocytes was higher in ARMC5-mutated nodules than in ARMC5-nonmutated nodules, and homogenous ARMC5 protein distribution was observed. The presence of arginine-vasopressin receptor (AVP1AR) and ectopic ACTH production were observed in both cell populations regardless of ARMC5 mutations; the numbers of serotonin receptor (5HT4R)- and proliferating cell nuclear antigen (PCNA)-positive cells were higher in macronodules carrying ARMC5 mutations than in those without mutations. Conclusions Our results suggest that the presence of ARMC5 mutations does not interfere with the pattern of distribution of spongiocytes and compact cells or with the presence of AVP1AR, gastric-inhibitory polypeptide receptor (GIPR) and ectopic ACTH. Nevertheless, the higher numbers of PCNA-positive cells in mutated nodules than in nonmutated nodules suggest that mutated ARMC5 can be related to higher proliferation rates in these cells. In conclusion, our results provide more information about the crosstalk among abnormal GPCRs, ectopic ACTH in steroidogenesis and the ARMC5 gene, which may be relevant in understanding the pathogenesis and diagnosis of patients with PMAH.

High Prevalence of Alterations in DNA Mismatch Repair Genes of Lynch Syndrome in Pediatric Patients with Adrenocortical Tumors Carrying a Germline Mutation on TP53.

Adrenocortical cancer is a rare malignant neoplasm associated with a dismal prognosis. Identification of the molecular pathways involved in adrenal tumorigenesis is essential for a better understanding of the disease mechanism and improvement of its treatment. The aim of this study is to define the prevalence of alterations in DNA mismatch repair (MMR) genes in Lynch syndrome among pediatric patients with adrenocortical neoplasia from southern Brazil, where the prevalence of a specific TP53 germline mutation (p.Arg337His) is quite high. Thirty-six pediatric patients were retrospectively evaluated. Immunohistochemistry (IHC) for the MMR enzymes MLH1, MSH2, MSH6, and PMS2, as well as next-generation sequencing (NGS) were performed. For IHC, 36 pediatric tumors were tested. In all of them, the expression of all evaluated MMR proteins was well-preserved. For NGS, 35 patients with pediatric tumor were tested. Three patients (8.57%) with the TP53 p.Arg337His germline mutation presented pathogenic and likely pathogenic variants in the MMR genes (two in MLH1 and one in MSH6). The prevalence of altered MMR genes among pediatric patients was elevated (8.57%) and higher than in colorectal and endometrial cancer cohorts. Pediatric patients with adrenocortical tumors should, thus, be strongly considered as at genetic risk for Lynch syndrome.

Allelic Variants of ARMC5 in Patients With Adrenal Incidentalomas and in Patients With Cushing's Syndrome Associated With Bilateral Adrenal Nodules.

Objective: Germline ARMC5 mutations are considered to be the main genetic cause of primary macronodular adrenal hyperplasia (PMAH). PMAH is associated with high variability of cortisol secretion caused from subclinical hypercortisolism to overt Cushing's syndrome (CS), in general due to bilateral adrenal nodules and rarely could also be due to non-synchronic unilateral adrenal nodules. The frequency of adrenal incidentalomas (AI) associated with PMAH is unknown. This study evaluated germline allelic variants of ARMC5 in patients with bilateral and unilateral AI and in patients with overt CS associated with bilateral adrenal nodules. Methods: We performed a retrospective multicenter study involving 123 patients with AI (64 bilateral; 59 unilateral). We also analyzed 20 patients with ACTH pituitary independent overt CS associated with bilateral adrenal nodules. All patients underwent germline genotyping analysis of ARMC5; abdominal CT and were classified as normal, possible or autonomous cortisol secretion, according to the low doses of dexamethasone suppression test. Results: We identified only one pathogenic allelic variant among the patients with bilateral AI. We did not identify any pathogenic allelic variants of ARMC5 in patients with unilateral AI. Thirteen out of 20 patients (65%) with overt CS and bilateral adrenal nodules were carriers of pathogenic germline ARMC5 allelic variants, all previously described. The germline ARMC5 mutation was observed in only one patient with bilateral AI; it was associated with autonomous cortisol secretion and showed to be a familial form. Conclusion: The rarity of germline ARMC5 mutations in AI points to other molecular mechanisms involved in this common adrenal disorder and should be investigated. In contrast, patients with overt Cushing's syndrome and bilateral adrenal nodules had the presence of ARMC5 mutations that were with high prevalence and similar to the literature. Therefore, we recommend the genetic analysis of ARMC5 for patients with established Cushing's syndrome and bilateral adrenal nodules rather than patients with unilateral AI.