RESUMO
PURPOSE: Molecular mechanisms of uveal melanoma development in association with high pigmentation are unclear. Tyrosinase Related Protein (TYRP1) is not only one of the important melanogenesis marker that contributes to melanin synthesis, but can also prevents the melanocyte death. The induction of melanogenesis leads to induction of HIF-1α which can affect the behavior of melanoma cells and its surrounding environment. The aim of our study was to determine the expression of TYRP1 and HIF-1α at the protein and RNA level and determine its prognostic significance. METHODS: In the present study, the expression of TYRP1 and HIF-1α was investigated on 61 formalin-fixed paraffin-embedded choroidal melanoma samples by immunohistochemistry. Fresh 50 samples were validated by real-time PCR. Results were correlated with clinicopathological parameters and Kaplan-Meier was performed to determine the prognostic significance. RESULTS: High immunoexpression of TYRP1 and HIF-1α was present in 61 and 54% of patients, respectively. Both TYRP1 and HIF-1α correlated well with high pigmentation and BAP1 (BRCA1 Associated Protein-1) loss (p < 0.05) at IHC level as well as transcriptional level. There was reduced metastatic free survival in patients with necrosis and this was statistically significant (p = 0.010). CONCLUSION: Our findings indicate that TYRP1 can be used as a potential biomarker in the development of targeted therapy in UM. Further studies on melanogenesis markers associated with TYRP1 could provide us a better understanding in this field.
Assuntos
Biomarcadores Tumorais/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Melanoma/metabolismo , Glicoproteínas de Membrana/metabolismo , Oxirredutases/metabolismo , Hipóxia Tumoral , Neoplasias Uveais/metabolismo , Adulto , Corioide , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Melaninas/biossíntese , Melanoma/mortalidade , Melanoma/patologia , Pigmentação , Fatores de Risco , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/metabolismo , Neoplasias Uveais/mortalidade , Neoplasias Uveais/patologiaRESUMO
BACKGROUND: The role of DNA damage response (DDR) proteins is poorly understood in uveal melanoma. ATR belongs to one of those proteins that induce DDR by arresting the cell cycle which leads to DNA repair. ATR is localized at position 23 on the same chromosome 3 where BAP1 is located at position 21.1 which is a known poor prognostic marker of UM. The aim of our study is to detect the expression of ATR at the protein and RNA levels and determine its prognostic significance. METHODS: Expression of nuclear ATR was investigated on sixty-nine UM patients. Formalin-fixed paraffin-embedded choroidal melanoma samples were taken to evaluate the expression of ATR. Fifty samples were also validated by real-time PCR. Results of both protein and mRNA were then correlated with clinicopathological parameters. To determine the prognostic significance, Kaplan-Meier and multivariate analyses were performed. RESULTS: Loss of ATR protein was seen in 72% cases which was statistically significant with epithelioid cell type (p = 0.005), tumor thickness (p = 0.016), mitotic figures (p = 0.001) and BAP1 loss (p < 0.001). At the transcriptional level loss of ATR was seen in 76% cases which were statistically significant with metastasis (p = 0.046), staging (0.044) and loss of BAP1 (p = 0.022). On multivariate analysis loss of ATR and tumor staging came out to be independent prognostic parameters. CONCLUSION: Our data suggest that ATR might serve as a potential prognostic marker in UM patients and could serve as a potential therapeutic target.
Assuntos
Dano ao DNA , Melanoma/genética , Neoplasias Uveais/genética , Adulto , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Células Epitelioides/metabolismo , Células Epitelioides/patologia , Feminino , Humanos , Masculino , Melanoma/metabolismo , Melanoma/mortalidade , Melanoma/patologia , Gradação de Tumores , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Neoplasias Uveais/metabolismo , Neoplasias Uveais/mortalidade , Neoplasias Uveais/patologiaRESUMO
PURPOSE: Uveal melanoma (UM) is the most common intraocular cancer with a high mortality rate that requires new research in the field of prevention and treatment. c-REL is a member of the nuclear factor κB (NF-κB) transcription factor family and an emerging regulator of tumorigenesis. Therefore, the objective of the study is to evaluate the constitutive expression of c-REL in uveal melanoma patients and its prognostic significance. METHODS: Detection of c-REL expression was carried out by immunohistochemistry in all 75 patients, and qRT-PCR performed on 58 fresh cases of uveal melanoma along with IL-6 status. Immunoblot was performed to validate immunohistochemistry results. Expression of c-REL protein correlated with clinicopathological parameters and overall survival of patients. RESULTS: Immunohistochemistry results revealed nuclear expression of the c-REL protein (56%) in our cases. Out of 75 cases, 31 cases showed nuclear expression, and 11 cases had cytoplasmic expression. qRT-PCR showed upregulation of the REL gene in 56.89% cases at the transcriptional level. There was a statistically significant difference in the overall survival of patients with c-REL nuclear immunopositivity (p = 0.0048). On multivariate analysis, scleral invasion and c-REL nuclear expression found to be an independent prognostic factor (p < 0.05) CONCLUSIONS: To the best of our knowledge, this was the first study reporting the expression of the c-REL protein in uveal melanoma. Strong nuclear immunoexpression of c-Rel suggests NFκB pathway activation which might be involved in the progression of the disease. Differential expression of c-REL protein may be used as an attractive target for the development of anticancer strategies.
Assuntos
Melanoma/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas c-rel/genética , Neoplasias Uveais/genética , Adulto , Idoso , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Melanoma/metabolismo , Melanoma/patologia , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-rel/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Neoplasias Uveais/metabolismo , Neoplasias Uveais/patologia , Quinase Induzida por NF-kappaBRESUMO
Background: Epigallocatechin 3 Gallate (EGCG) appears to act in appetite control through hormonal modulation. However, there is a lack of elucidation of EGCG's action mechanisms, especially in humans. The aim of this study was to evaluate the effects of acute EGCG supplementation on gastric emptying and its relation to blood hormones, glucose and appetite perceptions in healthy women. Methods: 22 healthy adult women were included in a randomized, double-blind, placebo-controlled crossover study. On two separate occasions, 1 week apart from each other, we offered 800 mg of corn starch (placebo) or 752 mg of EGCG. Appetite was assessed through gastric emptying; perceptions of hunger, desire to eat and satiation; and plasma insulin, adiponectin, leptin and glucose concentrations. The evaluations were carried out in fasting, 30, 90 and 150 min after supplementation. Results: EGCG supplementation induced higher relative gastric volume at 30 and 90 min. Satiation at 90 min was higher in the EGCG group. Adiponectin concentrations at 150 min were higher with EGCG, but no difference was found for glucose, insulin and leptin concentrations. Conclusions: Acute EGCG supplementation is able to delay gastric emptying in healthy women to a small, but statistically significant extent. This study was registered at the Brazilian Registry of Clinical Trials (ReBEC) as RBR-9svwrv.
Assuntos
Catequina/análogos & derivados , Suplementos Nutricionais , Esvaziamento Gástrico/efeitos dos fármacos , Adiponectina/sangue , Adiposidade , Apetite , Glicemia/metabolismo , Índice de Massa Corporal , Brasil , Catequina/administração & dosagem , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Fome , Insulina/sangue , Leptina/sangue , Saciação , Adulto JovemRESUMO
PURPOSE: Uveal melanoma, although a rare form of cancer, is the most common primary malignancy of the eye in adults. Nuclear factor-κB (NF-κB) is a transcription factor that transactivates genes involved in the regulation of cell growth, apoptosis, angiogenesis, and metastasis, but the molecular mechanisms that negatively regulate NF-κB activation are not fully understood. NF-κB can also be activated by DNA damage pathway through NEMO protein. Therefore, the objective of this study is to elucidate the role of NEMO/IKKγ protein in uveal melanoma patients. METHODS: Seventy-five formalin-fixed paraffin-embedded prospective tissues of uveal melanoma were included in the present study. These cases were reviewed and investigated for the expression of NEMO/IKKγ protein by immunohistochemistry and validated by western blotting along with the qRT-PCR for mRNA expression. Expression levels were correlated with the clinicopathological parameters and patients' outcome. RESULTS: Immunohistochemistry showed cytoplasmic expression of NEMO/IKKγ expression in only 22 out of 75 (29.33%) cases. This result was confirmed by western blotting, and correlated well with the immunohistochemical expression of NEMO/IKKγ protein (48 kDa). In addition, downregulation of this gene was found in 87.93% of the cases when compared with the normal tissues. On statistical analysis, loss of NEMO/IKKγ protein was correlated with neovascularization, high mitotic count, and presence of vascular loop (p < 0.05). There was less overall survival rate with low expression of NEMO/IKKγ protein in patients with uveal melanoma. CONCLUSION: This was the first study suggesting the relevant role of NEMO/IKKγ protein, and highlights the prognostic significance with outcome in uveal melanoma patients. This protein might be used as a screening biomarker in these patients after large-scale validation and translational studies.
Assuntos
Biomarcadores Tumorais/análise , Quinase I-kappa B/biossíntese , Melanoma/patologia , Neoplasias Uveais/patologia , Adulto , Idoso , Feminino , Humanos , Quinase I-kappa B/análise , Masculino , Melanoma/metabolismo , Melanoma/mortalidade , Pessoa de Meia-Idade , Prognóstico , Neoplasias Uveais/metabolismo , Neoplasias Uveais/mortalidadeRESUMO
Streptomyces venezuelae P(10) could produce extracellular chitinase in a medium containing 0.6% colloidal chitin that was fermented for 96 hours at 30 degrees C. The enzyme was purified to apparent homogeneity with 80% saturation of ammonium sulfate as shown by chitin affinity chromatography and DEAE-cellulose anion-exchange chromatography. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the enzyme showed a molecular weight of 66 kDa. The chitinase was characterized, and antifungal activity was observed against phytopathogens. Also, the first 15 N-terminal amino-acid residues of the chitinase were determined. The chitin hydrolysed products were N-acetylglucosamine and N, N'-diacetylchitobiose.
Assuntos
Antifúngicos/isolamento & purificação , Quitinases/isolamento & purificação , Streptomyces/enzimologia , Antifúngicos/química , Antifúngicos/farmacologia , Quitina/metabolismo , Quitinases/química , Quitinases/metabolismo , Quitinases/farmacologia , Cromatografia de Afinidade , Cromatografia por Troca Iônica , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , TemperaturaRESUMO
In an attempt to isolate chitinase producers from soil, a streptomycete strain was found potent using natural chitin as the substrate. Chitinolytic activity was tested directly on agar plates, also with crude enzyme. Chitinase assay showed that the isolate could produce 0.8 U/ml of the enzyme. The morphological, cultural, physiological and biochemical characters of the isolate P10 were studied, and identified as Streptomyces venezuelae P10.
Assuntos
Quitinases/química , Streptomyces/enzimologia , Acetilglucosamina/química , Ágar/química , Ágar/farmacologia , Animais , Asparagina/química , Braquiúros , Quitina/química , Quitinases/metabolismo , Coloides/química , Glucose/química , Glucose/metabolismo , Microscopia Eletrônica de Varredura , Fatores de TempoRESUMO
Os autores relatam um caso de zigomicose granulotomatosa visceral em uma paciente indígena xerente de quatro anos de idade, examinada por meio de ultra-sonografia e exames radiográficos. A confirmação diagnóstica foi feita pelo anatomopatológico. A literatura é brevemente revista e são discutidas a classificação, a fisiopatogenia e a evolução dessa enfermidade.
Assuntos
Pré-Escolar , Humanos , Feminino , Mucormicose , Zigomicose , Zigomicose/diagnósticoRESUMO
Os autores relatam um caso de fratura do hâmulo do hamato, conseqüente a acidente em via pública, fazendo uma revisäo da literatura para este raro tipo de patologia. Utilizam, além de radiografias convencionais, o recurso da tomografia computadorizada