Nephrogenic adenoma (NA) is a rare benign lesion commonly occurring in the urinary bladder that poses challenges to devising a diagnosis. In this study, 21 cases of NAs were studied by performing immunohistochemistry for PAX8, p63, CK903, PSA, S100A1, BerEP4, and CEA on routine tissue sections. PAX8 showed diffuse moderate to strong (2+ and 3+) nuclear staining in all of NAs (n = 6 and 15, respectively) and negative in the normal urothelium (n = 15). Nuclear staining for p63 was not seen in any case of NAs examined (n = 19) and was diffuse and strong (3+) in the normal urothelium (n = 14). High-molecular-weight keratin CK903 showed weak (1+) diffuse staining in all of the NAs examined (n = 19) and diffuse and moderate to strong positivity in the normal urothelium (n = 16). PSA staining was negative in both of the NAs (n = 21) and normal urothelium (n = 16). S100A1 showed strong (3+) diffuse staining in 19 of 20 of the NAs examined (n = 19) and diffuse weak (1+) (n = 14) to moderate (n = 3) staining in the normal urothelium. BerEP4 showed focal to diffuse, mild to moderate (1+ and 2+) cytoplasmic staining in all of NAs (n = 2 and 19) and negative in the normal urothelium (n = 19). CEA staining was negative in both of the NAs (n = 21) and normal urothelium (n = 17). A panel composed of PAX8, p63, PSA, S100A1, and CEA appears to be sensitive and specific in differentiating NA from its mimics of urothelial and prostatic origins.

Exposure to perfluorooctane sulfonic acid (PFOS) is known to induce thyroid-related adverse effects in aquatic organisms. Because an antioxidant defense mechanism is one of the key functions of the thyroid gland, we examined whether preexposure to PFOS could disrupt thyroid function and enhance cadmium (Cd)-induced oxidative stress in fish. Zebrafish embryos were exposed to control or 0.5 mg/L PFOS for 7 d after fertilization and subsequently exposed to 0.038 mg/L of Cd(2+) or a mixture of the PFOS and Cd for an additional 3 d until 10 d postfertilization (dpf). Survival rates, body length, messenger RNA (mRNA) expressions related to thyroid function and oxidative stress, the levels of thyroid hormones, and malondialdehyde and antioxidant enzyme activities were measured. Significant down-regulation of mRNAs related to thyroid function (thyroid hormone receptor-alpha [THRα], thyroid hormone receptor-beta [THRβ], hematopoietically expressed homeobox [hhex], and paired box gene 8 [pax8]) and decrease of throxine (T4) levels were observed in the PFOS preexposure group, suggesting that PFOS preexposure would influence the performance of thyroid gland in the later stages of life. Certain genes relative to oxidative stress, such as superoxide dismutase 1 (sod1) and heat shock protein 70 (hsp70), in the PFOS preexposure group were significantly up-regulated when the larvae were subsequently exposed to Cd or to the mixture of PFOS and Cd. Glutathione S-transferase activity and malondialdehyde levels of the PFOS-preexposed group were increased significantly by Cd exposure. Significant decrease of the survival rates and body length of fish were observed at 10 dpf among the larvae that were previously exposed to PFOS. These results suggest that preexposure to PFOS could affect antioxidant defense mechanisms and potentially increase the toxicity of Cd on mRNA expression and enzyme activity level responses, as well as on survival or growth of individuals.

Thyroid carcinomas represent only 1% of all human malignancies, but more than 90% of endocrine tumors. It can be histologically divided into papillary, follicular, anaplastic or medullary thyroid carcinomas. Here we report the genetic causes of the development of these tumors. For papillary thyroid carcinoma formation of fused genes of tyrosine kinases (RET proto-oncogene, NTRK1 proto-oncogene and met proto-oncogene) with other genes is typical. They can activate these kinases and induce mutation in BRAF gene. The presence of PAX8/PPARgamma fused gene and ras mutations are important in the development of follicular thyroid carcinoma. Anaplastic thyroid carcinoma derives from the dedifferentiation of papillary and follicular carcinomas as a consequence of mutation or loss of heterozygozity in p53 gene. Medullary thyroid carcinoma comes from parafollicular C-cells, where point somatic and germ-line mutations (in familial form of medullary thyroid carcinoma or in multiple endocrine neoplasia type 2) in the RET proto-oncogene determine its development. Identification of these specific genetic alternations for each type of carcinoma can contribute to precision of the diagnosis, explanation of the origin of carcinomas, establishment of prognosis of the disease or in future as a tool for the target gene therapy.

Two cases of a primary mediastinal tumor showing both thymoma and seminoma elements are presented. The patients were 2 men, aged 32 and 34 years, respectively. Clinically, both patients presented with symptoms related to their mediastinal masses, namely, chest pain and shortness of breath. Neither patient had any previous history of malignancy elsewhere. Diagnostic imaging revealed the presence of large anterior mediastinal masses. Both patients underwent thoracotomy with complete resection of their tumors. Grossly, the lesions measured 6 and 8 cm in greatest diameter, respectively and were tan and firm without areas of hemorrhage or necrosis. Both tumors appeared to be well circumscribed and grossly not involving any adjacent structures. Histologic sections showed the presence of distinct areas in the same tumor mass corresponding to conventional thymoma, whereas other areas corresponded to seminoma. Both components appeared to be present in almost equal proportions in the tumor. Immunohistochemical studies showed distinct labeling for each component: the thymoma component was positive for CAM5.2, Pax8, and cytokeratin 5/6; the seminoma component was positive for CAM5.2, SALL4, OCT3/4, and placental-like alkaline phosphatase. Both patients are currently alive and well 12 and 18 months after surgery, respectively. The cases herein described highlight the importance of ample sampling in mediastinal tumors and document for the first time the existence of combined thymoma-thymic seminomas.

Differentiated thyroid cancers (papillary--PTC and follicular--FTC) are the most common endocrine malignancies. The recent progresses in the understanding of PTC and FTC pathogenesis are summarized in this review. In PTC, a single mutation of BRAF (the gene for the B-type Raf kinase) (V600E) is responsible for the disease in 40-50% of patients, especially in older people and is associated with a poorer clinicopathological outcome. Due to these characteristics, its use as a specific diagnostic and prognostic marker for PTC in cytological specimens is being implemented. Another important cause of PTC is rearrangements of the RET tyrosine kinase receptor (RET/PTC), which represent a recombination of the promoter and N-terminal domain of a partner gene with the C-terminal region of the RET gene, resulting in a chimeric gene with a protein product containing a constitutively activated RET tyrosine kinase, responsible for 20-30% patients, specially the younger or after radiation. The pathogenesis of FTC is less understood. A chromosomal translocation between the transcription factor PAX8 and the peroxisome proliferator-activated receptorgamma (PPARgamma) occurs in 30-50% of patients; however, the presence of PAX8-PPARgamma is also demonstrated in follicular adenomas. Therefore, there is no complete evidence that PAX8-PPARgamma is the cause of FTC. Another finding in FTC is mutations on the RAS gene, which excludes PAX8-PPARgamma rearrangements. Several genes, as TRgamma, PTEN, PKAR1A, DDIT3, ARG2, ITM1 and C1orf24--some discovered by techniques of differential gene expression--, have been recently implicated in the pathogenesis of FTC.

Hypoplastic and/or cystic kidneys have been found in both LDL receptor-related protein 6 (Lrp6)- and β-catenin-mutant mouse embryos, and these proteins are key molecules for Wnt signaling. However, the underlying mechanisms of Lrp6/β-catenin signaling in renal development and cystic formation remain poorly understood. In this study, we found evidence that diminished cell proliferation and increased apoptosis occur before cystic dysplasia in the renal primordia of Lrp6-deficient mouse embryos. The expression of Ret proto-oncogene (Ret), a critical receptor for the growth factor glial cell line-derived neurotrophic factor (GDNF), which is required for early nephrogenesis, was dramatically diminished in the mutant renal primordia. The activities of other representative nephrogenic genes, including Lim1, Pax2, Pax8, GDNF, and Wnt11, were subsequently diminished in the mutant renal primordia. Molecular biology experiments demonstrated that Ret is a novel transcriptional target of Wnt/β-catenin signaling. Wnt agonist lithium promoted Ret expression in vitro and in vivo. Furthermore, Lrp6-knockdown or lithium treatment in vitro led to downregulation or upregulation, respectively, of the phosphorylated mitogen-activated protein kinases 1 and 3, which act downstream of GDNF/Ret signaling. Mice with single and double mutations of Lrp6 and Ret were perinatal lethal and demonstrated gene dosage-dependent effects on the severity of renal hypoplasia during embryogenesis. Taken together, these results suggest that Lrp6-mediated Wnt/β-catenin signaling modulates or interacts with a signaling network consisting of Ret cascades and related nephrogenic factors for renal development, and the disruption of these genes or signaling activities may cause a spectrum of hypoplastic and cystic kidney disorders.

Squamous differentiation (SD) and morular metaplasia (MM) are frequently present in uterine endometrioid adenocarcinoma (EAC) and can mimic areas of solid tumor. We used immunohistochemical stains to further characterize these lesions, and to determine which markers would help to distinguish these metaplasias from areas of solid growth in EAC. The pathology database was searched for diagnoses of EAC from 1997 to 2007, the hematoxylin and eosin-stained slides were reviewed, and 143 cases with SD, MM, or both (SD+MM) were identified. A panel of immunohistochemical stains was performed. In particular, we were interested in PAX2 and PAX8, recently studied markers of Müllerian tissue as potential markers for differentiation of metaplasias and tumor. In addition, estrogen receptor and progesterone receptor, and Her-2/neu, were examined to determine whether there was a differential expression between the metaplasias and solid tumor that may be diagnostically useful. In addition, to further characterize MM and SD, bcl-2 as a marker of cell regulation and inhibition of apoptosis, p16 as a surrogate marker for human papillomavirus, and p63 as a marker of mature SD were studied. Adjacent normal endometrium (NEM), when present, and 20 EAC cases (FIGO Grades 1-3) without SD or MM served as controls. PAX2 was positive in NEM (58/61, 95%) and was lost in SD (15/136, 11%), MM (1/25, 4%), and EAC (57/163, 35%), whereas PAX8 was positive in all NEM (61/61, 100%) and in the majority of SD (125/136, 92%), MM (19/25, 73%), and EAC (162/163, 99%). The estrogen receptor and the progesterone receptor were expressed by the majority of EAC (148/163, 91% and 144/163, 88%, respectively), whereas both were markedly diminished in SD (56/136, 41% and 58/136, 43%) and MM (4/25, 16% and 2/25, 8%). Approximately half of the MM was positive for bcl-2 (12/25, 48%), making it an unreliable marker. Her-2/neu was negative in all cases (0%). p16 was patchy in SD (111/136, 82%), MM (22/25, 88%), and EAC (154/163, 94%), whereas p63 was predominantly positive only in SD (96/136, 71%). Estrogen receptor and progesterone receptor, PAX2, and PAX8 were helpful in differentiating MM from SD, EAC, or NEM (P<0.05). In addition, p63 distinguished between SD and MM, supporting the theory that morules do not show characteristic mature SD.

The production of H2O2, which is essential to thyroid hormone synthesis, involves two NADPH oxidases: dual oxidases 1 and 2 (DuOx1 and DuOx2). A functional study with human DuOx genes and their 5'-flanking regions showed that DuOx1 and -2 promoters are different from thyroid-specific gene promoters. Furthermore, their transcriptional activities are not restricted to thyroid cells. While regulation of Tg (thyroglobulin) and TPO (thyroperoxidase) expression have been extensively studied, DuOx2 promoter regulation by hormones and transcriptional factors need to be more explored. Herein we investigated the role of TSH, insulin and insulin-like growth factor 1 (IGF-1), as well as the cAMP effect on DuOx2 promoter (ptx41) activity in transfected rat thyroid cell lines (PCCL3). We also assessed DuOx2 promoter activity in the presence of transcriptional factors crucial to thyroid development such as TTF-1 (thyroid transcription factor 1), PAX8, CREB, DREAM, Nkx2.5 and the coactivator TAZ in HeLa and HEK 293T-transfected cells. Our results show that TSH and forskolin, which increase cAMP in thyroid cells, stimulated DuOx2 promoter activity. IGF-1 led to pronounced stimulation, while insulin induction was not statistically different from DuOx2 promoter basal activity. All transcriptional factors selected for this work and coactivator TAZ, except DREAM, stimulated DuOx2 promoter activity. Moreover, Nkx2.5 and TAZ synergistically increased DuOx2 promoter activity. In conclusion, we show that DuOx2 expression is regulated by hormones and transcription factors involved in thyroid organogenesis and carcinogenesis, reinforcing the importance of the control of H2O2 generation in the thyroid.

A 91-year-old woman was admitted with persistent pyrexia, anorexia and weight loss. A chest radiograph showed multiple circular masses of various sizes. Chest computed tomography revealed multiple pleural tumors without any lung lesion. The ultrasound-guided biopsy specimens demonstrated diffusely-proliferated tumor cells with clear or vacuolated cytoplasm, which were positive for CD10, PAX8, vimentin and CAM5.2, but were negative for mesothelial cell markers such as HBME-1 and thrombomodulin. These findings indicated metastatic clear cell carcinoma of the kidney, and a solitary renal tumor was observed on abdominal computed tomography. It has been reported that pleural metastases constituted 12% of patients with progressive renal cell carcinoma, and most of the pleural metastases occurred secondary to lung metastasis. This was a rare case of renal cell carcinoma with an unusual chest image via an intriguing metastatic pathway, which was limited to pleura.

Cancer cell lines are critical models to study tumor progression and response to therapy. In 2008, we showed that approximately 50% of thyroid cancer cell lines were redundant or not of thyroid cancer origin. We therefore generated new authenticated thyroid cancer cell lines and patient-derived xenograft (PDX) models using in vitro and feeder cell approaches, and characterized these models in vitro and in vivo. We developed four thyroid cancer cell lines, two derived from 2 different patients with papillary thyroid cancer (PTC) pleural effusions, CUTC5, and CUTC48; one derived from a patient with anaplastic thyroid cancer (ATC), CUTC60; and one derived from a patient with follicular thyroid cancer (FTC), CUTC61. One PDX model (CUTC60-PDX) was also developed. Short tandem repeat (STR) genotyping showed that each cell line and PDX is unique and match the original patient tissue. The CUTC5 and CUTC60 cells harbor the BRAF (V600E) mutation, the CUTC48 cell line expresses the RET/PTC1 rearrangement, and the CUTC61 cells have the HRAS (Q61R) mutation. Moderate to high levels of PAX8 and variable levels of NKX2-1 were detected in each cell line and PDX. The CUTC5 and CUTC60 cell lines form tumors in orthotopic and flank xenograft mouse models. IMPLICATIONS: We have developed the second RET/PTC1-expressing PTC-derived cell line in existence, which is a major advance in studying RET signaling. We have further linked all cell lines to the originating patients, providing a set of novel, authenticated thyroid cancer cell lines and PDX models to study advanced thyroid cancer.

Oxyphilic (oncocytic) parathyroid lesions are very uncommon and their cytological features are rarely described. Due to the similarities in anatomical location and indistinguishable cytomorphological features, these lesions are easily confused with neoplastic and non-neoplastic thyroid lesions on fine needle aspiration (FNA). The diagnosis becomes more challenging in cases of unusual intrathyroidal location of the parathyroid lesions in the absence of clinical evidence of hyperparathyroidism, which simulate thyroid nodules clinically. We describe a case of intrathyroidal oxyphilic parathyroid carcinoma in a 66-year-old female, who presented with a dominant left "thyroid" nodule. FNA smears were cellular, comprising predominantly of oxyphilic cells arranged in papillary-like architecture with occasional nuclear grooves, which was mistaken for oncocytic variant of papillary carcinoma of the thyroid. The histological diagnosis of oxyphilic parathyroid "adenoma" was made following total thyroidectomy. The tumor, unfortunately, recurred 7 years later with associated multiple lung metastases. When dealing with thyroid lesions comprising predominantly of oncocytic cells, one should consider oxyphilic parathyroid neoplasms as one of the differential diagnosis. In difficult equivocal cases, a panel of immunocytochemical stains (PTH, GATA3, TTF-1, PAX8, and thyroglobulin) can be helpful. In addition, a combination of valuable clinical, radiological, and laboratory data, including serum calcium and parathyroid hormone levels are key to arriving at an accurate cytological diagnosis. Diagn. Cytopathol. 2016;44:688-692. © 2016 Wiley Periodicals, Inc.

Background: Thyroid ultrasound (US), fine needle aspiration biopsy (FNAB), and molecular testing have been widely used to stratify the risk of malignancy in thyroid nodules. The goal of this study was to investigate a novel diagnostic approach for cytologically indeterminate thyroid nodules (ITN) based upon a combination of US features and genetic alterations. Methods: We performed a pilot cohort study of patients with ITN (Bethesda III/IV), who underwent surgical treatment. Based on standardized sonographic patterns established by the American Thyroid Association (ATA), each ITN received an US score (X_US), ranging between 0 and 0.9 according to its risk of thyroid cancer (TC). DNA and RNA were extracted from pathologic material, available for all patients, and subjected to Oncomine™ Comprehensive Assay v2 (OCAv2) next-generation sequencing. Each genetic alteration was annotated based on its strength of association with TC and its sum served as the genomic classifier score (X_GC). The total risk score (TRS) was the sum of X_US and X_GC. ROC curves were generated to assess the diagnostic accuracy of X_US, X_GC, and TRS. Results: The study cohort consisted of 50 patients (39 females and 11 males), aged 47.5 ± 14.8 years. Three patients were excluded due to molecular testing failure. Among the remaining 47 patients, 28 (59.6%) were diagnosed with TC. BRAFV600E was the most common mutation in papillary TC, PAX8-PPARG fusion was present in NIFTP, pathogenic variants of SLX4, ATM, and NRAS were found in Hürthle cell TC and RET mutations in medullary TC. The diagnostic accuracy of X_GC and TRS was significantly higher compared with X_US (88 vs. 62.5%, p < 0.001; 85.2 vs. 62.5%, p < 0.001, respectively). However, this increased accuracy was due to significantly better sensitivity (80.7 vs. 34.6%, p < 0.001; 84.6 vs. 34.6%, p < 0.001, respectively) without improved specificity (94.7 vs. 90%, p = 0.55; 85.7 vs. 90%, p = 0.63, respectively). Conclusion: Molecular testing might not be necessary in ITN with high-risk US pattern (X_US = 0.9), as specificity of TC diagnosis based on Xus alone is sufficient and not improved with molecular testing. OCAv2 is useful in guiding the management of ITN with low-to-intermediate risk US features (X_US < 0.9), as it increases the accuracy of TC diagnosis.

Brominated flame retardants are known to disrupt thyroid hormone (TH) homeostasis in several vertebrate species, but the molecular mechanisms underlying this process and their effects on TH-sensitive tissues during the stages of early development are not well characterised. In this study, we exposed zebrafish (Danio rerio) embryo-larvae to 2,2',4,4'-tetrabromodiphenyl ether (BDE-47) and tetrabromobisphenol A (TBBPA) via the water for 96 h from fertilisation and assessed for lethality, effects on development and on the expression of a suite of genes in the hypothalamic-pituitary-thyroid (HPT) axis via both real time quantitative PCR (qRT-PCR) on whole body extracts and whole mount in situ hybridisation (WISH) to identify tissue targets. The 96-h lethal median concentration (96h-LC₅₀) for TBBPA was 0.9 μM and mortality was preceded by retardation of development (smaller animals) and morphological deformities including, oedemas in the pericardial region and tail, small heads, swollen yolk sac extension. Exposure to BDE-47 did not affect zebrafish embryo-larvae survival at any of the concentrations tested (1-100 μM) but caused yolk sac and craniofacial deformities, a curved spine and shorter tail at the highest exposure concentration. TBBPA exposure resulted in higher levels of mRNAs for genes encoding deiodinases (dio1), transport proteins (ttr), the thyroid follicle synthesis protein paired box 8 (pax8) and glucuronidation enzymes (ugt1ab) and lower levels of dio3b mRNAs in whole body extracts, with responses varying with developmental stage. BDE-47 exposure resulted in higher levels of thrb, dio1, dio2, pax8 and ugt1ab mRNAs and lower levels of ttr mRNAs in whole body extracts. TBBPA and BDE-47 therefore appear to disrupt the TH system at multiple levels, increasing TH conjugation and clearance, disrupting thyroid follicle development and altering TH transport. Compensatory responses in TH production/ metabolism by deiodinases were also evident. WISH analyses further revealed that both TBBPA and BDE-47 caused tissue-specific changes in thyroid receptor and deiodinase enzyme expression, with the brain, liver, pronephric ducts and craniofacial tissues appearing particularly responsive to altered TH signalling. Given the important role of TRs in mediating the actions of THs during key developmental processes and deiodinases in the control of peripheral TH levels, these transcriptional alterations may have implications for TH sensitive target genes involved in brain and skeletal development. These findings further highlight the potential vulnerability of the thyroid system to disruption by BFRs during early developmental windows.

Recent progress has been made in understanding the pathogenesis of neonatal thyroid disorders. Autosomal recessive inheritance of mutations of the thyroid peroxidase and thyroglobulin genes has been described in some patients with congenital hypothyroidism (CH) and a family history of CH. Autosomal recessive inheritance of mutations of the thyrotrophin (TSH) receptor gene has also been reported in patients with CH and thyroid hypoplasia, and autosomal dominant mutations of the PAX8 gene have been described in patients with different forms of thyroid dysgenesis. These discoveries are important for patients with CH diagnosed by neonatal screening, as these patients will have normal fertility. The molecular genetic analysis of mutations of the TSH gene in patients with familial and sporadic cases of isolated central CH, who are missed by TSH screening programmes, now enables rapid diagnosis and appropriate therapy in the neonate. In newborn infants with severe non-autoimmune hyperthyroidism, autosomal dominant gain-of-function mutations in the TSH receptor gene have been demonstrated. In these patients, molecular genetic studies are extremely helpful in therapeutic decision making, as early thyroid ablation is the only effective treatment that avoids the sequelae of long-term hyperthyroidism. Molecular genetic studies are therefore useful in the diagnostic work-up of neonatal thyroid alterations.

PAX8 is a transcription factor essential for thyroid gland development, as well as for the maintenance of the thyroid differentiated state in the adult. In particular, PAX8 has been comprehensively shown to regulate genes that are considered markers of thyroid differentiation. However, a better knowledge of genes transcriptionally regulated by PAX8 is desirable to clarify its role in endocrine syndromes and cancer susceptibility. In order to further investigate PAX8 downstream targets, we recently performed a genome-wide expression analysis following PAX8 knockdown in FRTL-5 thyroid cells and Neuropilin-2 was identified as a potential transcriptional target of PAX8. In this study, we determined the role of the transcription factor PAX8 in the regulation of Neuropilin-2 expression. Indeed, in thyroid cells PAX8 directly binds the Neuropilin-2 promoter leading to its transcriptional repression. Interestingly, we observed an inverse correlation between the expression of PAX8 and Neuropilin-2 in thyroid carcinoma tissues and cell lines compared to non-tumor counterparts, suggesting a critical role of PAX8 in regulating Neuropilin-2 expression in vivo. Notably, ectopic overexpression of PAX8 in FB-2 thyroid cancer cells promotes Neuropilin-2 downregulation producing a significant reduction in cell proliferation, migration ability, and invasion activity and reverting the cell phenotype from mesenchymal to a more epithelial one. These findings uncover the novel interplay between PAX8 and Neuropilin-2, which is likely to be important in the pathogenesis of thyroid diseases.

It is established that numerous somatic oncogene mutation (BRAF, NRAS, HRAS, KRAS) and gene translocations (RET/PTC, PAX8/PPAR-gamma) are associated with the development of thyroid cancer. In this study 22 intraoperative thyroid tissue samples (11 pathologic and 11 normal) were examined. Somatic single nucleotide polymorphisms were analyzed by LigthCycler melting method, while translocations were identified by real-time polymerase chain reaction technique. In tumorous sample 3 BRAF, 2 NRAS and one HRAS mutations were found, as well as one RET/PTC1 translocation. Results confirm international data showing that these oncogene mutations and translocations are linked to thyroid cancer. Cytological examination completed with genetic data may support the diagnosis of thyroid malignancies. In addition, genetic alterations may indicate malignant transformation and may become prognostic factors in future.

Fluorescence in situ hybridization (FISH) is increasingly gaining importance in clinical diagnostics settings. Due to the ability of the technique to detect chromosomal abnormalities in samples with low cellularity or containing a mixed population of cells even at a single-cell level, it has become more popular in cancer research and diagnosis. Here, we describe the FISH technique for detection of PAX8-PPARγ translocation in follicular thyroid neoplasms, and the optimal protocol for the detection of this fusion gene using in archival formalin-fixed paraffin-embedded (FFPE) thyroid tissue sections.

We present an unusual case of cerebellar hemangioblastoma characterized by rhabdoid features. The patient was a 35-year-old Japanese man with occipital neuralgia and exacerbating blurred vision. Magnetic resonance imaging revealed a left posterior cranial fossa tumor, which was isointense on T1-weighted images and hyperintense on T2-weighted images with marked homogeneous enhancement. Histology of the surgically resected tumor showed cellular-type hemangioblastoma with extensive proliferation of rhabdoid cells Immunohistochemistry analysis showed tumor cells positive for inhibin A, CD56, vimentin, INI-1, and vascular endothelial growth factor; negative for PAX8, CD10, epithelial membrane antigen, cytokeratin, (AE1/3), alpha-smooth muscle actin and D2-40; and had focal positivity for glial fibrillary acidic protein and S100. The Ki-67 labeling index was <1 %. Ultrastructural analysis revealed large lipid droplets and abundant intracellular accumulation of intermediate filaments. Based on these findings, the diagnosis was hemangioblastoma with focal rhabdoid features. After a 14-month follow-up, there was no evidence of recurrence. This is the first report of hemangioblastoma with rhabdoid features in the central nervous system. In addition, we discuss the possible pathogenesis.

Metastases represent the most common tumors of the central nervous system, with clear cell renal cell carcinomas showing a particular predilection to involve the brain. This report documents an unusual case of a patient with a chromophobe renal cell carcinoma presenting with a brain metastasis. A 58-year-old man presented with stroke-like symptomatology, including expressive aphasia, right side facial weakness, headaches and vomiting. CT imaging demonstrated a 4.7 cm left frontal lobe hemorrhagic mass. He underwent surgery with excision of the mass, which was marked by sheets of large cells with lightly eosinophilic to clear cytoplasm. PAX8 staining was positive and a diagnosis of clear cell carcinoma of probably renal origin was rendered. Subsequently, CT imaging of the abdomen revealed a 12.9 cm left renal mass. The patient underwent a left nephrectomy and a diagnosis of chromophobe renal cell carcinoma was made. The tumor was noted to extend into the perirenal fat and to have involved a paraaortic lymph node. Re-review of the frontal lobe lesion confirmed the tumor was the same. Chromophobe renal cell carcinomas are far less common than clear cell tumors, are less likely to metastasize, and generally have a more favorable overall prognosis. When they metastasize, they most commonly involve the liver, lung and lymph nodes, in contrast to the more common clear cell carcinomas that typically spread to the lungs, bone and brain.

The sodium-iodide symporter (NIS) mediates the uptake of I(-) by the thyroid follicular cell and is essential for thyroid hormone biosynthesis. Nis expression is stimulated by thyroid-stimulating hormone (TSH) and also requires paired box 8 (Pax8) to bind to its promoter. Pax8 binding activity depends on its redox state by a mechanism involving thioredoxin/thioredoxin reductase-1 (Txn/TxnRd1) reduction of apurinic/apyrimidinic endonuclease 1 (Ape1). In this study, we investigate the role of Se in Nis expression.

Selenium increases TSH-induced Nis expression and activity in rat thyroid cells. The stimulatory effect of Se occurs at the transcriptional level and is only observed for Nis promoters containing a Pax8 binding site in the Nis upstream enhancer, suggesting that Pax8 is involved in this effect. In fact, Se increases Pax8 expression and its DNA-binding capacity, and in Pax8-silenced rat thyroid cells, Nis is not Se responsive. By inhibiting Ape1 and TxnRd1 functions, we found that both enzymes are crucial for TSH and TSH plus Se stimulation of Pax8 activity and mediate the Nis response to Se treatment.

We describe that Se increases Nis expression and activity. We demonstrate that this effect is dependent on the redox functions of Ape1 and Txn/TxnRd1 through control of the DNA binding activity of Pax8.

Nis expression is controlled by Txn/Ape1 through a TSH/Se-dependent mechanism. These findings open a new field of study regarding the regulation of Nis activity in thyroid cells. Antioxid. Redox Signal. 24, 855-866.

Clear cell carcinoma (CCC) of the female genital tract usually arises in the ovary, endometrium, cervix and vagina. A rare site for CCC is the vulva, and moreover even rarer are the cases involving the Bartholin gland. A 54-year-old female was admitted for a 1.5×2 cm tumor at the level of the right Bartholin gland. The magnetic resonance imaging (MRI) exam revealed enlarged inguinal, pelvic and para-aortic lymph nodes but no other primary tumor. Microscopic examination revealed CCC. The tumor was positive for cytokeratin 7 (CK7), paired-box 8 (Pax8), napsin A and vimentin, negative for estrogen receptor (ER), progesterone receptor (PR), calretinin, cluster of differentiation 10 (CD10), carcinoembryonic antigen (CEA), p16 and p63. Also, p53 was expressed in 30-40% and Ki67 in 70% of the malignant cells. Given the clinical, imagistic, histological and immunohistochemical features of the tumor, we concluded that the tumor is a CCC of the Bartholin gland. Aim of the study is to signal a rare case of CCC of Bartholin gland. Since there are only two other cases reported in literature, the natural history and prognosis of the disease is not known, also there are no therapeutic guidelines regarding this rare tumor so appropriate treatment is uncertain. Therefore, it is important that new cases are reported for a better understanding of this rare condition. Bartholin gland carcinoma is a pathology quite rarely encountered in practice. The positive diagnosis is eminently histological and immunohistochemistry. Bartholin gland CCC is an extremely rare diagnosis with, to our knowledge, only two other cases reported in literature, but with a potential aggressive clinical behavior and poor outcome.

Primary vulvar clear cell carcinoma (CCC) is extremely rare. In this article, we report a primary vulvar CCC along with immunohistochemical and gene mutation analyses results and literature review to discuss the clinicopathological features and tumorigenesis of this rare tumor. A 70-year-old (gravida 2 para 2) Japanese woman complained of bleeding from a vulvar mass at a past episiotomy site. A 1.8 × 1.8 × 0.5 cm exophytic sessile mass was present on the vestibular area inside the left labium minora. Radical local excision of the tumor and resection of the inguinal lymph nodes on both sides were performed. Histopathology revealed a vulvar CCC with immunohistochemical positivity for PAX8, HNF-1β, ER, and CA125, and negativity for p16, CD10, GATA3, PTEN, and PAX2, suggesting its Müllerian origin. No lymph node metastasis was observed. The tumor was a 5-mm exophytic growth without deep stromal invasion; thus, it was difficult to measure the invasion depth assuming a squamous cell carcinoma. To investigate pathogenic/oncogenic mutations in 50 cancer-related genes, we used the AmpliSeq Cancer Hotspot Panel. However, no pathogenic/oncogenic mutations were detected. Literature review revealed that most cases of vulvar CCC are associated with vulvar endometriosis. In particular, cases with clinically evident endometriosis at the episiotomy scar should be carefully observed. Evidence-based pathological stages of vulvar adenocarcinoma including CCC remain to be established owing to its rarity, with nationwide or global accumulation of cases required in future.

Different factors are involved in thyroid function and proliferation such as thyrotropin (TSH), insulin, growth factors, iodide, etc. TSH and IGF1/insulin increase proliferation rate and stimulate genes involved in thyroid differentiation. In the present study, we analyse the physiological regulation of NOX4 expression by TSH, insulin and iodine, and the role of NOX4 on thyroid genes expression. Differentiated rat thyroid cells (FRTL-5) were incubated in the presence or absence of TSH/insulin and TTF2, PAX8, TPO, NIS, NOX4, TGFβ1, FOXO1/3 mRNA levels were examined by Real Time PCR. We showed that TSH and insulin repress NOX4 expression and appears to be inversely correlated with some thyroid genes. SiRNA targeted knockdown of NOX4 increased mRNA levels of TGFβ1, TPO, PAX8, TTF2, FOXO1 and FOXO3. A PI3K inhibitor (LY294002), increases the expression of NIS, TTF2 and FOXO1/3, however PI3K/AKT pathway does not regulate NOX4 expression. We observed that iodine increased NOX4 expression and knockdown of NOX4 reduced ROS and reversed the inhibitory effect of iodine on NIS, TPO, PAX8 and TTF2 expression. Our findings provide strong evidence that NOX4 could be a novel signaling modulator of TSH/insulin pathway and would have a critical role in the autoregulatory mechanism induced by iodine.