Assuntos
Paracoccidioides , Paracoccidioidomicose , Humanos , Paracoccidioidomicose/diagnóstico , PeleRESUMO
Abstract Pilomatricomas are benign tumors originating from the capillary matrix, which may present as solitary lesions or, less commonly, multiple. Myotonic dystrophy and familial adenomatous polyposis are the most frequently associated disorders with multiple pilomatricomas. There are few reports relating these tumors to other genetic syndromes. Rubinstein-Taybi syndrome is a rare autosomal dominant disorder characterized by intellectual disability and typical dysmorphic characteristics. There are five case reports relating to multiple pilomatricoma to Rubinstein-Taybi syndrome, an association that needs to be clarified. For this reason, we report the first case of multiple pilomatricoma in monozygotic twins with typical Rubinstein-Taybi syndrome.
Assuntos
Humanos , Síndrome de Rubinstein-Taybi , Neoplasias Cutâneas , Pilomatrixoma/sangue , Doenças do CabeloRESUMO
Pilomatricomas are benign tumors originating from the capillary matrix, which may present as solitary lesions or, less commonly, multiple. Myotonic dystrophy and familial adenomatous polyposis are the most frequently associated disorders with multiple pilomatricomas. There are few reports relating these tumors to other genetic syndromes. Rubinstein-Taybi syndrome is a rare autosomal dominant disorder characterized by intellectual disability and typical dysmorphic characteristics. There are five case reports relating to multiple pilomatricoma to Rubinstein-Taybi syndrome, an association that needs to be clarified. For this reason, we report the first case of multiple pilomatricoma in monozygotic twins with typical Rubinstein-Taybi syndrome.
Assuntos
Doenças do Cabelo , Pilomatrixoma , Síndrome de Rubinstein-Taybi , Neoplasias Cutâneas , Humanos , Pilomatrixoma/cirurgiaRESUMO
BACKGROUND: Thyroid hormone regulates a wide range of cellular activities, including the balance between cell proliferation and differentiation. The thyroid-hormone-inactivating type 3 deiodinase (DIO3, D3) has been shown to be reactivated in human neoplasias. Here, we evaluated DIO3 expression in human papillary thyroid carcinoma (PTC). METHODS: Tumor and surrounding normal thyroid tissue were collected from 26 unselected patients with PTC. Clinical data were retrospectively reviewed in medical records. DIO3 mRNA levels were measured by real-time polymerase chain reaction and D3 activity by paper-descendent chromatography. Studies of DIO3 gene regulation were performed in a human PTC-derived cell line (K1 cells). BRAF(V600E) mutation was identified in DNA from paraffin-embedded tissues by direct sequencing. Immunohistochemistry analyses were performed using a specific human D3 antibody. RESULTS: Increased D3 activity was detected in all 26 PTC samples analyzed as compared with adjacent thyroid tissue. The augmentations in D3 activity were paralleled by increased DIO3 mRNA levels (approximately fivefold). In PTC-derived cells, DIO3 transcripts were further upregulated by the transforming growth factor ß1 (TGFß1). Interestingly, preincubation with mitogen-activated protein kinase (MAPK) cascade inhibitors U0126 (ERK pathway) and SB203580 (p38 pathway) decreased DIO3 mRNA levels and blocked the TGFß1-induced increase in DIO3 transcripts, suggesting that D3 induction might be mediated through the MAPK signaling pathway. Accordingly, DIO3 mRNA and activity levels were significantly higher in BRAF(V600E)-mutated samples (p=0.001). Increased D3 activity was correlated with tumor size (r=0.68, p=0.003), and associated with lymph node (p=0.03) or distant metastasis (p=0.006) at diagnosis. Conversely, decreased levels of the thyroid-hormone-activating type 2 deiodinase (DIO2) gene were observed in PTC, which might contribute to further decreases in intracellular thyroid hormone levels. Increased D3 expression was also observed in follicular thyroid carcinoma but not in medullary or anaplastic thyroid carcinoma samples. CONCLUSIONS: These results indicate that the malignant transformation of thyroid follicular cell toward PTC promotes opposite changes in DIO3 and DIO2 expression by pretranscriptional mechanisms. The association between increased levels of D3 activity and advanced disease further supports a role for intracellular triiodothyronine concentration on the thyroid tumor cell proliferation or/and dedifferentiation.
Assuntos
Carcinoma/enzimologia , Iodeto Peroxidase/biossíntese , Neoplasias da Glândula Tireoide/enzimologia , Adulto , Butadienos/farmacologia , Carcinoma Papilar , Linhagem Celular Tumoral , Criança , Inibidores Enzimáticos/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/farmacologia , Imuno-Histoquímica , Iodeto Peroxidase/análise , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/fisiologia , Masculino , Pessoa de Meia-Idade , Mutação , Nitrilas/farmacologia , Proteínas Proto-Oncogênicas B-raf/genética , Piridinas/farmacologia , Estudos Retrospectivos , Câncer Papilífero da Tireoide , Fator de Crescimento Transformador beta1/metabolismo , Adulto JovemRESUMO
Nonthyroidal illness syndrome (NTIS) is a state of low serum 3,5,3' triiodothyronine (T3) that occurs in chronically ill patients; the degree of reduction in T3 is associated with overall prognosis and survival. Iodthyronine deiodinases are enzymes that catalyze iodine removal from thyroid hormones; type I and II deiodinase (D1 and D2, respectively) convert the prohormone thyroxine T4 to active T3, whereas the type III enzyme (D3) inactivates T4 and T3. Increased production of cytokines, including IL-6, is a hallmark of the acute phase of NTIS, but the role of cytokines in altered thyroid hormone metabolism is poorly understood. Here, we measured the effect of IL-6 on both endogenous cofactor-mediated and dithiothreitol-stimulated (DTT-stimulated) cell sonicate deiodinase activities in human cell lines. Active T3 generation by D1 and D2 in intact cells was suppressed by IL-6, despite an increase in sonicate deiodinases (and mRNAs). N-acetyl-cysteine (NAC), an antioxidant that restores intracellular glutathione (GSH) concentrations, prevented the IL-6-induced inhibitory effect on D1- and D2-mediated T3 production, which suggests that IL-6 might function by depleting an intracellular thiol cofactor, perhaps GSH. In contrast, IL-6 stimulated endogenous D3-mediated inactivation of T3. Taken together, these results identify a single pathway by which IL-6-induced oxidative stress can reduce D1- and D2-mediated T4-to-T3 conversion as well as increasing D3-mediated T3 (and T4) inactivation, thus mimicking events during illness.