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1.
Biomol Biomed ; 23(1): 26-36, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36036061

RESUMO

Papillary thyroid carcinoma (PTC) is the most common type of endocrine cancer, with an increasing incidence worldwide. The treatment of PTC is currently the subject of clinical controversy, making it critically important to identify molecular markers that would help improve the risk stratification of PTC patients and optimize the therapeutic approach. The VHL tumor suppressor gene has been implicated in tumorigenesis of various types of carcinoma and linked with their aggressive biological behavior. The role of VHL in the origin and development of PTC has only recently begun to be revealed. In this narrative review we attempt to summarize the existing knowledge that implicates VHL in PTC pathogenesis and to outline its potential significance as a candidate molecular biomarker for the grouping of PTC patients into high and low risk groups.


Assuntos
Carcinoma Papilar , Neoplasias da Glândula Tireoide , Humanos , Câncer Papilífero da Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/diagnóstico , Carcinoma Papilar/diagnóstico , Genes Supressores de Tumor , Biomarcadores , Proteína Supressora de Tumor Von Hippel-Lindau/genética
2.
Basic Clin Pharmacol Toxicol ; 131(6): 514-524, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36180380

RESUMO

Several pyrazoloquinolinone (PQ) ligands were recently discovered as functionally selective positive modulators at the PQ site of α6-containing GABAA receptors. PQs are also neutral modulators at the benzodiazepine site. We assessed the influence of PQ compounds from three structural groups (PZ-II-029 and related deuterated analogues DK-I-56-1, RV-I-029, DK-I-60-3 and DK-I-86-1; LAU 463 and related analogues DK-I-58-1 and DK-II-58-1; and DK-I-87-1), alone and in combination with diazepam, on the behaviour of male Sprague-Dawley rats. An excellent behavioural safety profile of all tested PQs was demonstrated in the spontaneous locomotor activity, rotarod, loss of righting reflex and pentylenetetrazol tests. In interaction studies, only PZ-II-029 and its analogues prevented the ataxic effects of the benzodiazepine, as assessed in the rotarod test and during monitoring of rat locomotor activity after awakening from the loss of righting reflex. Published electrophysiological profiles of PQ ligands imply that positive modulation elicited at α6-GABAA receptors that contain the γ2 and δ subunit, rather than their neutral modulatory action at the benzodiazepine site, may prevent the ataxic action of diazepam. Thus, PZ-II-029 and its deuterated analogues are not prone to untoward interactions with benzodiazepines and may indeed completely abolish their ataxic action, seen at therapeutic, and especially toxic concentrations.


Assuntos
Diazepam , Receptores de GABA-A , Animais , Ratos , Masculino , Diazepam/farmacologia , Ratos Sprague-Dawley , Receptores de GABA-A/química , Benzodiazepinas/farmacologia , Ligantes , Ácido gama-Aminobutírico , Ataxia , Moduladores GABAérgicos
3.
CNS Neurosci Ther ; 28(11): 1767-1778, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35822698

RESUMO

AIMS: GABAergic modulation involved in cognitive processing appears to be substantially changed in Alzheimer's disease (AD). In a widely used 5xFAD model of AD, we aimed to assess if negative and positive allosteric modulators of α5 GABAA receptors (NAM and PAM, respectively) would affect social interaction, social, object and spatial memory, and neuroinflammation. METHODS: After 10-day treatment with PAM, NAM, or solvent, 6-month-old transgenic and non-transgenic 5xFAD mice underwent testing in a behavioral battery. Gene expressions of IL-1ß, IL-6, TNF-α, GFAP, and IBA-1 were determined in hippocampus and prefrontal cortex by qPCR. RESULTS: PAM treatment impaired spatial learning in transgenic females compared to solvent-treated transgenic females, and social recognition in transgenic and non-transgenic males. NAM treatment declined social interaction in transgenic and non-transgenic males, while had beneficial effect on cognitive flexibility in non-transgenic males compared to solvent-treated non-transgenic males. Transgenic animals have not fully displayed cognitive symptoms, but neuroinflammation was confirmed. NAM reduced proinflammatory gene expressions in transgenic females and astrogliosis in transgenic males compared to pathological controls. CONCLUSION: PAM and NAM failed to exert favorable behavioral effects in transgenic animals. Suppression of neuroinflammation obtained with NAM calls for more studies with GABAergic ligands in amyloid beta- and/or tau-dependent models with prominent neuroinflammation.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Interleucina-6/metabolismo , Masculino , Memória , Camundongos , Camundongos Transgênicos , Doenças Neuroinflamatórias , Receptores de GABA-A/genética , Interação Social , Solventes , Fator de Necrose Tumoral alfa/metabolismo , Ácido gama-Aminobutírico
4.
J Eat Disord ; 9(1): 85, 2021 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-34256847

RESUMO

BACKGROUND AND AIMS: Oxytocin, a nine amino acid peptide synthesised in the hypothalamus, has been widely recognised for its role in anxiolysis, bonding, sociality, and appetite. It binds to the oxytocin receptor (OXTR)-a G-protein coupled receptor-that is stimulated by the actions of oestrogen both peripherally and centrally. Studies have implicated OXTR genotypes in conferring either a risk or protective effect in autism, schizophrenia, and eating disorders (ED). There are numerous DNA variations of this receptor, with the most common DNA variation being in the form of the single nucleotide polymorphisms (SNPs). Two OXTR SNPs have been most studied in relation to ED: rs53576 and rs2254298. Each SNP has the same allelic variant that produces genotypes AA, AG, and GG. In this critical review we will evaluate the putative role of rs53576 and rs2254298 SNPs in ED. Additionally, this narrative review will consider the role of gene-environment interactions in the development of ED pathology. FINDINGS: The OXTR SNPs rs53576 and rs2254298 show independent associations between the A allele and restrictive eating behaviours. Conversely, the G allele of the OXTR rs53576 SNP is associated with binging behaviours, findings that were also evident in neuroanatomy. One study found the A allele of both OXTR SNPs to confer risk for more severe ED symptomatology while the G allele conferred some protective effect. An interaction between poor maternal care and rs2254298 AG/AA genotype conferred increased risk for binge eating and purging in women. CONCLUSIONS: Individual OXTR SNP are unlikely in themselves to explain complex eating disorders but may affect the expression of and/or effectiveness of the OXTR. A growing body of G x E work is indicating that rs53576G homozygosity becomes disadvantageous for later mental health under early adverse conditions but further research to extend these findings to eating pathology is needed. The GWAS approach would benefit this area of knowledge.


Oxytocin is a chemical made in the brain that affects human behaviour in areas from anxiety, bonding right through to appetite. Oxytocin works by binding to a specific cellular receptor. In humans, the genes that specify this receptor are found in slightly different versions that are inherited from each parent. Research has suggested that individuals who possess speicfic combinations of oxytocin receptor gene variants may be more susceptible to certain kinds of mental illness. This paper considers two different versions of the oxytocin receptor gene most studied in relation to eating disorders. The two different versions considered in this review do not seem to affect the structure of the oxytocin receptor itself. Together, research indicates that the presence or absence of a particular receptor gene variant in an individual might have some predictive capability in respect of potential susceptibility to eating disorders. However, further research is necessary as some of the findings are contradictory. In addition, environmental factors­such as poor maternal care early in life­have also been demonstrated to be important in determining whether an individual will develop an eating disorder. Research in this area would benefit from non-hypothesis driven studies.

5.
Sci Transl Med ; 13(582)2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33627486

RESUMO

Chemoresistance remains the major challenge for successful treatment of acute myeloid leukemia (AML). Although recent mouse studies suggest that treatment response of genetically and immunophenotypically indistinguishable AML can be influenced by their different cells of origin, corresponding evidence in human disease is still largely lacking. By combining prospective disease modeling using highly purified human hematopoietic stem or progenitor cells with retrospective deconvolution study of leukemia stem cells (LSCs) from primary patient samples, we identified human hematopoietic stem cells (HSCs) and common myeloid progenitors (CMPs) as two distinctive origins of human AML driven by Mixed Lineage Leukemia (MLL) gene fusions (MLL-AML). Despite LSCs from either MLL-rearranged HSCs or MLL-rearranged CMPs having a mature CD34-/lo/CD38+ immunophenotype in both a humanized mouse model and primary patient samples, the resulting AML cells exhibited contrasting responses to chemotherapy. HSC-derived MLL-AML was highly resistant to chemotherapy and expressed elevated amounts of the multispecific anion transporter ABCC3. Inhibition of ABCC3 by shRNA-mediated knockdown or with small-molecule inhibitor fidaxomicin, currently used for diarrhea associated with Clostridium difficile infection, effectively resensitized HSC-derived MLL-AML toward standard chemotherapeutic drugs. This study not only functionally established two distinctive origins of human LSCs for MLL-AML and their role in mediating chemoresistance but also identified a potential therapeutic avenue for stem cell-associated treatment resistance by repurposing a well-tolerated antidiarrhea drug already used in the clinic.


Assuntos
Leucemia Mieloide Aguda , Proteína de Leucina Linfoide-Mieloide , Animais , Células-Tronco Hematopoéticas , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Camundongos , Proteína de Leucina Linfoide-Mieloide/genética , Estudos Prospectivos , Estudos Retrospectivos
6.
Med Oncol ; 35(2): 17, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-29340905

RESUMO

A growing body of evidence suggests a role of the von Hippel-Lindau (VHL) tumor suppressor gene in the progression of papillary thyroid carcinoma (PTC). Our previous study of VHL in PTCs showed that lower VHL expression was associated with aggressive tumor features, but we found no evidence for VHL downregulation through common genetic or epigenetic modifications. Several studies pointed to a role of microRNA-92a (miR-92a) in the regulation of VHL expression in different cancers. In the present study, we examined the expression levels of VHL mRNA and miR-92a in 42 pairs of PTCs and matched non-tumor thyroid tissues by means of quantitative RT-PCR. We explored the correlation between them and their association with clinicopathological parameters. The results revealed that both VHL and miR-92a were either up- or downregulated in PTCs compared to corresponding non-tumor tissues. On univariate analysis, lower VHL levels were significantly associated with extrathyroid spread (P = 0.022) and capsular invasion (P = 0.032). Multivariate analysis confirmed the association of low VHL with extrathyroid spread (OR 0.246, 95% CI 0.069-0.872, P = 0.038). Higher miR-92a among PTC tissues associated with the presence of nodal metastases (univariate analysis: P = 0.012; multivariate: OR 4.703, 95% CI 1.109-19.938, P = 0.036). A negative correlation between VHL and miR-92a was observed in a subgroup of PTCs having vascular invasion (P = 0.033, r = - 0.673). The data here reported demonstrate that the expression of both VHL and miR-92a is deregulated in PTC tissues and that in some PTCs they may have opposite roles. These roles, as well as their diagnostic and/or prognostic utility, remain to be clarified.


Assuntos
Adenocarcinoma Folicular/secundário , Biomarcadores Tumorais/metabolismo , Carcinoma Papilar/secundário , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Glândula Tireoide/patologia , Proteína Supressora de Tumor Von Hippel-Lindau/metabolismo , Adenocarcinoma Folicular/genética , Adenocarcinoma Folicular/metabolismo , Adolescente , Adulto , Idoso , Biomarcadores Tumorais/genética , Carcinoma Papilar/genética , Carcinoma Papilar/metabolismo , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adulto Jovem
7.
J Clin Invest ; 127(5): 1918-1931, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28394257

RESUMO

The eleven-nineteen leukemia (ENL) protein family, composed of ENL and AF9, is a common component of 3 transcriptional modulators: AF4-ENL-P-TEFb complex (AEP), DOT1L-AF10-ENL complex (referred to as the DOT1L complex) and polycomb-repressive complex 1 (PRC1). Each complex associates with chromatin via distinct mechanisms, conferring different transcriptional properties including activation, maintenance, and repression. The mixed-lineage leukemia (MLL) gene often fuses with ENL and AF10 family genes in leukemia. However, the functional interrelationship among those 3 complexes in leukemic transformation remains largely elusive. Here, we have shown that MLL-ENL and MLL-AF10 constitutively activate transcription by aberrantly inducing both AEP-dependent transcriptional activation and DOT1L-dependent transcriptional maintenance, mostly in the absence of PRC1, to fully transform hematopoietic progenitors. These results reveal a cooperative transcriptional activation mechanism of AEP and DOT1L and suggest a molecular rationale for the simultaneous inhibition of the MLL fusion-AF4 complex and DOT1L for more effective treatment of MLL-rearranged leukemia.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Rearranjo Gênico , Histona-Lisina N-Metiltransferase/metabolismo , Leucemia/metabolismo , Metiltransferases/metabolismo , Proteína de Leucina Linfoide-Mieloide/metabolismo , Proteínas Nucleares/metabolismo , Fatores de Elongação da Transcrição/metabolismo , Animais , Proteínas de Ligação a DNA/genética , Feminino , Células HEK293 , Histona-Lisina N-Metiltransferase/genética , Humanos , Células K562 , Leucemia/genética , Metiltransferases/genética , Camundongos , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas Nucleares/genética , Fatores de Elongação da Transcrição/genética
8.
PLoS One ; 9(12): e114511, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25490036

RESUMO

Alterations of the von Hippel-Lindau (VHL) tumor suppressor gene can cause different hereditary tumors associated with VHL syndrome, but the potential role of the VHL gene in papillary thyroid carcinoma (PTC) has not been characterized. This study set out to investigate the relationship of VHL expression level with clinicopathological features of PTC in an ethnically and geographically homogenous group of 264 patients from Serbia, for the first time. Multivariate logistic regression analysis showed a strong correlation between low level of VHL expression and advanced clinical stage (OR = 5.78, 95% CI 3.17-10.53, P<0.0001), classical papillary morphology of the tumor (OR = 2.92, 95% CI 1.33-6.44, P = 0.008) and multifocality (OR = 1.96, 95% CI 1.06-3.62, P = 0.031). In disease-free survival analysis, low VHL expression had marginal significance (P = 0.0502 by the log-rank test) but did not appear to be an independent predictor of the risk for chance of faster recurrence in a proportion hazards model. No somatic mutations or evidence of VHL downregulation via promoter hypermethylation in PTC were found. The results indicate that the decrease of VHL expression associates with tumor progression but the mechanism of downregulation remains to be elucidated.


Assuntos
Carcinoma/patologia , RNA Mensageiro/metabolismo , Neoplasias da Glândula Tireoide/patologia , Proteína Supressora de Tumor Von Hippel-Lindau/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar , Criança , Metilação de DNA , Análise Mutacional de DNA , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Câncer Papilífero da Tireoide
9.
Med Oncol ; 31(6): 977, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24781337

RESUMO

MicroRNAs play essential role in breast carcinoma progression and invasion. Our principal goals were to assess clinicopathological and prognostic correlations of microRNA-21 (miR-21) expression levels in a group of 39 Serbian breast cancer patients with invasive lobular (ILC), ductal (IDC), or mixed (ILC-IDC) breast carcinomas and in order to discover the role of miR-21 in potential novel form of stratification of the patients with different estrogen receptor (ER) and progesterone receptor (PR) status. MiR-21 expression levels were measured by stem-loop real-time RT-PCR using TaqMan technology. ER, PR, human epidermal growth factor 2 receptor (Her-2), and proliferative index (Ki-67) were evaluated by immunohistochemistry. MiR-21 levels do not vary among ILC, IDC, and ILC-IDC subgroups. MiR-21 expression levels varied significantly in the age, tumor size, Ki-67, and different grade (p = 0.030, p = 0.036, p = 0.027 and p = 0.032, respectively) subgroups. ER+ and PR+ showed higher miR-21 levels than their negative receptor status paired groups ER- and PR- with p = 0.012 and p = 0.018, respectively. MiR-21 positively correlated with ER and PR status (p = 0.018, ρ = 0.379 and p = 0.034, ρ = 0.345, respectively). Our findings suggest that miR-21 emulates transitional form of expression and that the levels of expression might be useful for stratification of the patients with different receptor status with the purpose to seek for new therapy approaches especially for the patients with the lack of response to conventional endocrine therapy.


Assuntos
Neoplasias da Mama/genética , MicroRNAs/genética , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/genética , Carcinoma Lobular/metabolismo , Carcinoma Lobular/patologia , Feminino , Humanos , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Valores de Referência , Sérvia
10.
Med Oncol ; 31(3): 867, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24488617

RESUMO

MicroRNA-21 (miR-21) overexpression is characteristic for various types of tumors, but it is still unknown whether its expression levels differ between invasive and non-invasive breast carcinomas. The main goal of the study was to determine the difference in miR-21 expression among normal tissue, non-invasive, invasive with non-invasive component, and pure invasive breast cancer samples, to explain its potential role and significance in breast cancer invasiveness. The second goal was to propose miR-21 as molecular marker of breast cancer invasiveness and potential target for future anti-miR therapies for the prevention of invasion and metastasis. In order to reveal the role of miR-21 in breast cancer invasiveness, we measured miR-21 expression levels in 44 breast cancer and four normal samples by stem-loop real-time RT-PCR using TaqMan technology. Relative expression levels of miR-21 were significantly higher in invasive than in other groups (P=0.002) and significantly higher in invasive compared with invasive with non-invasive component group in histological (P=0.043) and nuclear grade 2 (P=0.036), estrogen-receptor-positive (ER+) (P=0.006), progesterone-receptor-positive (PR+) (P=0.008), ER+PR+ (P=0.007), and proliferation index (Ki-67)≤20% (P=0.036) tumors. Our findings suggest that miR-21 could be independent molecular marker of breast cancer invasiveness and potential target for future anti-miR therapies for the prevention of invasion and metastasis.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Carcinoma Lobular/genética , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/secundário , Carcinoma Lobular/metabolismo , Carcinoma Lobular/secundário , Estudos de Casos e Controles , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Técnicas Imunoenzimáticas , Metástase Linfática , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Prognóstico , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida
11.
Thyroid ; 24(3): 593-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23844610

RESUMO

BACKGROUND: Neuroendocrine tumor (NET) of the thyroid other than medullary carcinoma is extremely rare. We describe here a case of calcitonin-negative small cell neuroendocrine carcinoma (SCNEC), which occurred in a thyroid gland that had previously been irradiated at high dose (60 Gy) for pharyngeal cancer, with molecular analyses for follicular cell origin. PATIENT FINDINGS: The tumor cells were small with fine chromatin, inconspicuous nucleoli, and inapparent cytoplasm, and showed neuroendocrine architectures such as palisading, rosettes, and trabeculae. Mitotic figures were numerous exceeding 10 mitoses per 10 high-power fields. The tumor cells invaded into several vessels and metastasized to regional lymph nodes. Immunohistochemically, the tumor cells were strongly positive for neuroendocrine markers and thyroglobulin (Tg), a marker of thyroid follicular cells but negative for calcitonin and carcinoembryonic antigen (CEA). Expression of Tg and thyrotropin receptor (TSHR) were confirmed by quantitative real-time polymerase chain reaction (RT-PCR). Ki-67 labeling index was more than 70% in the tumor cells. Taken together, the tumor was diagnosed as SCNEC of the thyroid. Genetic analyses also revealed microsatellite abnormalities of the phosphatase and tensin homolog (PTEN) gene, suggesting that functional loss of PTEN contributes to carcinogenesis. CONCLUSIONS: This is the first report describing a SCNEC of the thyroid with molecular analyses that provide evidence for a follicular epithelial origin.


Assuntos
Carcinoma de Células Pequenas/patologia , Tumores Neuroendócrinos/patologia , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/patologia , Biomarcadores Tumorais , Carcinoma de Células Pequenas/etiologia , Carcinoma de Células Pequenas/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Tumores Neuroendócrinos/etiologia , Tumores Neuroendócrinos/metabolismo , Receptores da Tireotropina/genética , Receptores da Tireotropina/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/etiologia , Neoplasias da Glândula Tireoide/metabolismo , Fatores de Transcrição
12.
Histopathology ; 63(5): 726-34, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24004175

RESUMO

AIMS: In a previous report, we proposed that analysis of 53BP1 expression by immunofluorescence could be a useful tool in estimating the level of genomic instability (GIN), as well as the malignant potential, of thyroid tumours. In an attempt to clarify the value of 53BP1 expression as a new molecular marker for the aggressiveness of thyroid papillary microcarcinoma (PMC), we assessed the association between the type of 53BP1 expression and clinicopathological features such as tumour size, extrathyroidal invasion, lymph node metastasis and BRAF(V) (600E) mutation of PMC. METHODS AND RESULTS: A total of 36 surgically resected thyroid tumours, including 13 PMC and 23 conventional papillary thyroid carcinomas (PTC), were available for this study. Analysis using immunofluorescence revealed that the incidence of an abnormal or high DNA damage response (DDR) type of 53BP1 expression was significantly higher in PTC than PMC. BRAF(V) (600E) mutation was not associated significantly with tumour aggressiveness in either PMC or PTC cases. Abnormal/high DDR type of 53BP1 expression was associated closely with both BRAF(V) (600E) mutation and papillary and/or trabecular architecture of PMC. CONCLUSIONS: Abnormal/high DDR type of 53BP1 expression might be associated with GIN and papillary/trabecular morphology at an early stage of PTC carcinogenesis through BRAF(V) (600E) mutation.


Assuntos
Carcinoma Papilar/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Proto-Oncogênicas B-raf/metabolismo , Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Adulto , Carcinoma Papilar/genética , Carcinoma Papilar/patologia , Feminino , Instabilidade Genômica , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas Proto-Oncogênicas B-raf/genética , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/patologia , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
13.
Eur J Cancer Prev ; 22(6): 561-5, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23512068

RESUMO

Thyroid carcinomas in children and adolescents are rare tumors and the most common among them is papillary thyroid cancer (PTC). Its etiology is still under research and has not been clearly defined thus far, especially in young individuals. The aim of this case-control study was to determine potential risk factors for the development of PTC in children and adolescents. This type of study has not been carried out previously in this age group. A case-control study was carried out during a 15-year period, between 1995 and 2009. The case group included 75 patients with PTC younger than 20 years of age, with the youngest patient being 6.5 years old; 45 patients were female and 30 were male. The control group included the same number of participants, and the cases were individually matched by sex, age, and place of residence. Conditional univariate and multivariate logistic regression methods were applied in data analysis. According to univariate logistic regression analysis, PTC in children and adolescents was significantly related to the following factors: family history of thyroid cancer, family history of residence in an endemic-goiter area, family history of benign thyroid disease, and family history of nonthyroid malignant tumors. According to the multivariate logistic regression method, PTC in children and adolescents was independently related to a family history of thyroid cancer (odds ratio=4.5, 95% confidence interval=1.2-19.8) and a family history of nonthyroid malignant tumors (odds ratio=3.8, 95% confidence interval=1.4-8.7). In conclusion, all of the factors associated with the development of PTC in children and adolescents were related to their family history.


Assuntos
Carcinoma Papilar/patologia , Neoplasias da Glândula Tireoide/patologia , Adolescente , Adulto , Carcinoma Papilar/etiologia , Estudos de Casos e Controles , Criança , Feminino , Seguimentos , Humanos , Masculino , Estadiamento de Neoplasias , Prognóstico , Fatores de Risco , Neoplasias da Glândula Tireoide/etiologia , Adulto Jovem
14.
BMC Cancer ; 12: 224, 2012 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-22682753

RESUMO

BACKGROUND: Struma ovarii (SO) is a rare form of ovarian mature teratoma in which thyroid tissue is the predominant element. Because of its rarity, the differential diagnosis between benign and malignant SO has not been clearly defined. It is believed that malignant transformation of SO has similar molecular features with and its prognosis corresponds to that of malignant tumors originating in the thyroid. CASE PRESENTATION: We report 35-year-old woman with bilateral ovarian cysts incidentally detected by ultrasound during the first trimester of pregnancy. Four months after delivery of a healthy child without complication she was admitted to the hospital for acute abdominal pain. Laparoscopic left adnexectomy was performed initially in a regional hospital; right cystectomy was done later in a specialized clinic. Intraoperative frozen section and a final pathology revealed that the cyst from the left ovary was composed of mature teratomatous elements, normal thyroid tissue (>50%) and a non-encapsulated focus of follicular variant of papillary thyroid carcinoma (PTC).Normal and cancerous thyroid tissues were tested for BRAF and RAS mutations by direct sequencing, and for RET/PTC rearrangements by RT-PCR/Southern blotting. A KRAS codon 12 mutation, the GGT → GTT transversion, corresponding to the Gly → Val amino acid change was identified in the absence of other genetic alterations commonly found in PTC. CONCLUSION: To the best of our knowledge, this is the first time this mutation is described in a papillary thyroid carcinoma arising in struma in the ovarii. This finding provides further evidence that even rare mutations specific for PTC may occur in such tumors. Molecular testing may be a useful adjunct to common differential diagnostic methods of thyroid malignancy in SO.


Assuntos
Carcinoma/genética , Genes ras , Mutação , Neoplasias Ovarianas/genética , Estruma Ovariano/genética , Neoplasias da Glândula Tireoide/genética , Substituição de Aminoácidos , Sequência de Bases , Carcinoma/diagnóstico , Carcinoma Papilar , Códon , Feminino , Humanos , Neoplasias Ovarianas/diagnóstico , Estruma Ovariano/diagnóstico , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/diagnóstico
15.
Endocr J ; 59(6): 517-22, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22504175

RESUMO

Thyroglossal duct cyst (TDC) carcinoma is a comparable rare entity and treatment strategies have not been standardized. Here, we report a favorable outcome of TDC carcinoma patients based on our therapeutic strategy. Twelve patients with TDC carcinoma treated in our department from 1986 to 2012 were enrolled. Ten patients underwent Sistrunk's procedure in other institutions and referred to our institution for re-operation after the diagnosis of TDC carcinoma and the remaining two underwent initial surgery in our institution. Eleven patients were diagnosed as papillary and one as follicular carcinoma originating from TDC. We performed total thyroidectomy for 11, and limited thyroidectomy for one patient. Three patients (25%) had carcinoma lesions in the thyroid. We routinely dissected level I bilaterally and 6 of 11 patients (55%) with papillary carcinoma-type TDC carcinoma had metastasis. Level II/III nodes were biopsied and if positive, we performed level II-IV dissection. Of the 5 patients positive for level II/III, 2 were also positive for level IV. For the 3 patients with synchronous carcinoma in the thyroid, we performed level VI dissection and two had metastasis in this level. To date, 1 patient showed a recurrence to the lung, but none of the patients in our series died of carcinoma. For surgery of TDC carcinoma, Sistrunk's procedure, total thyroidectomy with level I dissection is mandatory. Whether level II-IV dissection is performed depends on pathology of biopsied level II/III nodes. Level VI dissection is also recommended especially when carcinoma lesions are pre/intra operatively detected in the thyroid.


Assuntos
Adenocarcinoma Folicular/cirurgia , Carcinoma/cirurgia , Cisto Tireoglosso/cirurgia , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia/métodos , Adenocarcinoma Folicular/complicações , Adulto , Carcinoma/complicações , Carcinoma Papilar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esvaziamento Cervical/métodos , Prognóstico , Sérvia , Cisto Tireoglosso/complicações , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/complicações , Resultado do Tratamento
16.
Infect Genet Evol ; 11(6): 1475-80, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21601012

RESUMO

Hepatitis B virus (HBV) is classified into 8 genotypes with distinct geographical distribution. Genotype D (HBV/D) has the widest distribution area and is comprised of 7 subgenotypes. Subgenotypes D1, D2 and D3 appear worldwide, while D4-D7 have a more restricted distribution. Within the Mediterranean area, HBV/D and subgenotype D3 are the most prevalent. The purpose of this study was to characterize the full genome of Serbian HBV/D3 isolates by comparison and phylogenetic analysis with HBV/D3 sequences (66 samples) found in GeneBank/DDBJ databases from different parts of the world. Isolates were obtained from three patients diagnosed with chronic hepatitis B (HBsAg+). All three isolates have two very rare nucleotide substitutions, A929T and T150A, which indicate the same ancestor. Phylogenetic analysis of HBV/D3 genome sequences throughout the world follows an ethno-geographical origin of isolates with rare exceptions, which could be explained by human travelling and migration. The geographically close but ethnically different Serbian and Italian isolates clustered in the same subnode, and on a common branch with strains from Northern Canada. To test the apparently close HBV phylogenetic relationship between completely separated patients from Serbia and Northern Canada we analyzed in depth a 440 bp region of the HBsAg from Canadian (n=73) and Serbian (n=70) isolates. The constructed parsimony tree revealed that strains from Serbia and Northern Canada fell along the same branch which indicates independent evolution within regions of each country. Considering that HBsAg sequence has limited variability for phylogenetic analyses, our hypothesis needs further confirmation with more HBV complete genome sequences.


Assuntos
Genoma Viral , Vírus da Hepatite B/genética , Hepatite B Crônica/virologia , Adulto , Criança , Evolução Molecular , Feminino , Genótipo , Vírus da Hepatite B/classificação , Hepatite B Crônica/epidemiologia , Humanos , Masculino , Epidemiologia Molecular , Dados de Sequência Molecular , Filogenia , Filogeografia , Análise de Sequência de DNA , Sérvia/epidemiologia
17.
Endocr J ; 58(5): 381-93, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21498916

RESUMO

Molecular pathogenesis of papillary thyroid carcinoma (PTC) is largely associated with mutational changes in the BRAF, RAS family and RET genes. Our aim was to assess clinico-pathological and prognostic correlations of these PTC-specific gene alterations, with a particular emphasis on the BRAF mutation, in a group of 266 Serbian PTC patients, for the first time. The reference center-based retrospective cohort included 201 (75.6%) females and 65 (24.4%) males aged 48.0±16.1 years (8-83 years old, range) diagnosed and treated for PTC during 1993-2008. Follow-up period was 53.1±41.6 months (7-187 months, range). BRAF and RAS mutations were determined by direct sequencing of genomic DNA. RET/PTC rearrangements were analyzed by RT-PCR/Southern blotting. Genetic alterations were detected in 150/266 tumors (56.4%). One tumor displayed two genetic alterations. The BRAF(V600E) was found in 84/266 (31.6%) cases, RAS mutations in 11/266 (4.1%) and RET/PTC in 55/266 (20.7%; 42/266 (15.8%) RET/PTC1 and 13/266 (4.9%) RET/PTC3). On multivariate analysis BRAF(V600E) was associated with the classical papillary morphology (P = 0.05), the higher pT category (P = 0.05) and advanced clinical stage (P = 0.03). In a proportional hazard model, BRAF(V600E) did not appear to be an independent risk factor for the faster recurrence (P = 0.784). We conclude that under the extensive thyroid surgery and limited application of radioiodine ablation BRAF(V600E) may not be an indicator of poorer disease-free survival during the short to middle follow-up period. However, it has a potential to contribute to patients stratification into high- and low-risk groups.


Assuntos
Carcinoma Papilar/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-ret/genética , Neoplasias da Glândula Tireoide/genética , Proteínas ras/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma , Carcinoma Papilar/epidemiologia , Criança , Feminino , Rearranjo Gênico , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Mutação Puntual , Prognóstico , Sérvia/epidemiologia , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/epidemiologia , Neoplasias da Glândula Tireoide/patologia
18.
Diagn Pathol ; 5: 17, 2010 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-20222992

RESUMO

The presence of ectopic breast tissue in axillary lymph nodes (ALN) is a benign condition that must be differentiated from primary or metastatic carcinoma. Here we report a patient who underwent excision of enlarged ALN 10 years after she had received surgical treatment of ipsilateral breast for an intracystic intraductal papilloma (IDP). Histological examination of the removed ALN revealed that the proliferative lesion consisted of papillary and tubular structures lined by luminal cuboidal cells and a distinct outer layer of myoepithelial cells resembling IDP of the breast. Immunostaining with a set of immunohistochemical markers including AE/AE3, alpha-smooth muscle actin and p63 in combination with estrogen and progesterone receptors confirmed the diagnosis of ectopic IDP.This case shows that even though benign proliferative change in ectopic breast tissue is an extremely rare phenomenon, this possibility should be taken into account for correct diagnosis.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Mama , Coristoma , Doenças Linfáticas/patologia , Segunda Neoplasia Primária/diagnóstico , Papiloma Intraductal/patologia , Adulto , Axila , Biópsia , Neoplasias da Mama/química , Neoplasias da Mama/cirurgia , Proliferação de Células , Erros de Diagnóstico/prevenção & controle , Feminino , Humanos , Imuno-Histoquímica , Excisão de Linfonodo , Doenças Linfáticas/metabolismo , Doenças Linfáticas/cirurgia , Mastectomia , Segunda Neoplasia Primária/química , Segunda Neoplasia Primária/cirurgia , Papiloma Intraductal/química , Papiloma Intraductal/cirurgia , Valor Preditivo dos Testes , Resultado do Tratamento
19.
J Virol Methods ; 161(2): 265-70, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19591875

RESUMO

Hepatitis B virus (HBV) infection is a global health problem associated with severe liver disorders. Viral load and HBV genotype affect the clinical outcome, guide antiviral therapy and provide long term prognosis for HBV infected patients. Various types of detection and quantitation assays are currently in use with a different effectiveness. The aim of this study was to develop a method that would provide simultaneous identification and quantitation of genotypes A and D in a single-tube reaction. Sera from infected patients were analyzed by a TaqMan based real time PCR. Optimized reagents were used for HBV DNA quantitation while the genotypes A and D were quantified separately by our design of the assay. Multiplex real time PCR was achieved and was specific for HBV genotypes A and D within a single-tube reaction. Simulation of mixed virus populations was identified reproducibly in vitro. Quantitation of these individual genotypes was exceptionally reliable, so much so that the sum of individual genotypes was equal to the total viral load determined in a separate reaction. Therefore, a straightforward, conceptually simple and reliable approach to issues involving HBV genotypes A and D is submitted. Identity and exact titer of these genotypes in the Caucasian population can now be determined easily.


Assuntos
Variação Genética , Vírus da Hepatite B/genética , Hepatite B Crônica/diagnóstico , Sequência de Bases , DNA Viral/análise , DNA Viral/sangue , DNA Viral/genética , Vírus da Hepatite B/isolamento & purificação , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Sensibilidade e Especificidade , Carga Viral , População Branca
20.
Med Oncol ; 21(4): 319-24, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15579915

RESUMO

Sequence alterations in the RET proto-oncogene are becoming increasingly important to clinical assessment of the malignant disease of the thyroid. A spectrum of mutations is necessary to establish comprehensive phenotype to genotype relationship relevant to diagnosis and therapy of thyroid malignancies. We aimed to append to the increasing database of these oncogenic lesions and, therefore, analyzed DNA from tumor tissue and constitutive DNA from a patient with thyroid carcinoma. Mutational screening and sequence characterization of the RET proto-oncogene was performed to include part of the intronic sequences. We report a germline sequence variant in DNA from the patient diagnosed with microfollicular thyroid carcinoma. The carcinoma presented not as fully developed medullar carcinoma (MTC) but as microfollicular carcinoma with tendency to evolve into MTC. We characterized the sequence variant located in the intron 10 of the RET oncogene as an A to G substitution denoted IVS10 + 4G. The described sequence alteration generates a chi-like sequence surrounded by several chi-like sequences with recombinational potential. Such alteration may be involved in the pathogenesis of the microfollicular carcinoma via genome destabilization through homologous recombination in the process of tumor progression. This result further substantiates the importance of the database correlating specific sequence variations in the RET gene with distinct disease phenotypes.


Assuntos
Adenocarcinoma Folicular/genética , Bases de Dados Genéticas , Proteínas Oncogênicas/genética , Mutação Puntual , Receptores Proteína Tirosina Quinases/genética , Neoplasias da Glândula Tireoide/genética , Adenocarcinoma Folicular/patologia , Sequência de Bases , Transformação Celular Neoplásica , Análise Mutacional de DNA , DNA de Neoplasias , Feminino , Humanos , Íntrons , Pessoa de Meia-Idade , Mitógenos , Dados de Sequência Molecular , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas c-ret , Análise de Sequência de DNA , Neoplasias da Glândula Tireoide/patologia
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