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1.
Cell Mol Neurobiol ; 43(2): 813-826, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35366170

RESUMO

Medulloblastoma is the most common type of pediatric malignant primary brain tumor, and about one-third of patients die due to disease recurrence and most survivors suffer from long-term side effects. MB is clinically, genetically, and epigenetically heterogeneous and subdivided into at least four molecular subgroups: WNT, SHH, Group 3, and Group 4. We evaluated common differentially expressed genes between a Brazilian RNA-seq GSE181293 dataset and microarray GSE85217 dataset cohort of pediatric MB samples using bioinformatics methodology in order to identify hub genes of the molecular subgroups based on PPI network construction, survival and functional analysis. The main finding was the identification of five hub genes from the WNT subgroup that are tumor suppressors, and whose lower expression is related to a worse prognosis for MB patients. Furthermore, the common genes correlated with the five tumor suppressors participate in important pathways and processes for tumor initiation and progression, as well as development and differentiation, and some of them control cell stemness and pluripotency. These genes have not yet been studied within the context of MB, representing new important elements for investigation in the search for therapeutic targets, prognostic markers or for understanding of MB biology.


Assuntos
Neoplasias Encefálicas , Neoplasias Cerebelares , Meduloblastoma , Humanos , Criança , Meduloblastoma/genética , Meduloblastoma/metabolismo , Meduloblastoma/patologia , Prognóstico , Neoplasias Cerebelares/genética , Neoplasias Cerebelares/metabolismo , Neoplasias Cerebelares/patologia , Perfilação da Expressão Gênica , Biomarcadores Tumorais/genética
2.
Int J Mol Sci ; 24(11)2023 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-37298628

RESUMO

Increased glycolytic metabolism plays an important role in B-cell precursor Acute Lymphoblastic Leukemia (BCP-ALL). We previously showed that IGFBP7 exerts mitogenic and prosuvival effects in ALL by promoting IGF1 receptor (IGF1R) permanence on the cell surface, thus prolonging Akt activation upon IGFs/insulin stimulation. Here, we show that sustained activation of the IGF1R-PI3K-Akt axis concurs with GLUT1 upregulation, which enhances energy metabolism and increases glycolytic metabolism in BCP-ALL. IGFBP7 neutralization with a monoclonal antibody or the pharmacological inhibition of the PI3K-Akt pathway was shown to abrogate this effect, restoring the physiological levels of GLUT1 on the cell surface. The metabolic effect described here may offer an additional mechanistic explanation for the strong negative impact seen in ALL cells in vitro and in vivo after the knockdown or antibody neutralization of IGFBP7, while reinforcing the notion that it is a valid target for future therapeutic interventions.


Assuntos
Proteínas de Ligação a Fator de Crescimento Semelhante a Insulina , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Proteínas Proto-Oncogênicas c-akt , Humanos , Linhagem Celular Tumoral , Proliferação de Células , Transportador de Glucose Tipo 1/genética , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor IGF Tipo 1/metabolismo
3.
Pediatr Blood Cancer ; 69(7): e29553, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34971073

RESUMO

Pediatric adrenocortical tumors (ACT) are rare aggressive neoplasms with heterogeneous prognosis. Despite extensive efforts, identifying reliable prognostic factors for pediatric patients with ACT remains a challenge. MicroRNA (miRNA) signatures have been associated with cancer diagnosis, treatment response, and prognosis of several types of cancer. However, the role of miRNAs has been poorly explored in pediatric ACT. In this study, we performed miRNA microarray profiling on a cohort of 37 pediatric ACT and nine nonneoplastic adrenal (NNA) samples and evaluated the prognostic significance of abnormally expressed miRNAs using Kaplan-Meier plots, log-rank test, and Cox regression analysis. We identified a total of 98 abnormally expressed miRNAs; their expression profile discriminated ACT from NNAs. Among the 98 deregulated miRNAs, 17 presented significant associations with patients' survival. In addition, higher expression levels of hsa-miR-630, -139-3p, -125a-3p, -574-5p, -596, -564, -1321, and -423-5p and lower expression levels of hsa-miR-377-3p, -126-3p, -410, -136-3p, -29b-3p, -29a-3p, -337-5p, -143-3p, and 140-5p were significantly associated with poor prognosis, tumor relapse, and/or death. Importantly, the expression profile of these 17 miRNAs stratified patients into two groups of ACTs with different clinical outcomes. Although some individual miRNAs exhibit potential prognostic values in ACTs, only the 17 miRNA-based expression clustering was considered an independent prognostic factor for 5-year event-free survival (EFS) compared to other clinicopathological features. In conclusion, our study reports for the first time associations between miRNA profiles and childhood ACT prognosis, providing evidence that miRNAs could be useful biomarkers to discriminate patients with favorable and unfavorable clinical outcomes.


Assuntos
Perfilação da Expressão Gênica , MicroRNAs , Biomarcadores , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Criança , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Prognóstico
4.
Support Care Cancer ; 30(1): 695-702, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34363492

RESUMO

Among the treatment-related acute toxic effects, risks for bloodstream infections (BSIs) are associated with several variables. The authors carried out a retrospective cohort study with 259 children and adolescents with ALL, treated with the GBTLI-LLA 2009 protocol, in order to assess the incidence of BSIs in the induction phase; to determine the risk factors for these BSIs; and to identify the related microorganisms and sensitivity profile of the microorganisms related to these infections. BSIs were documented in 19.3% of patients. The isolated microorganisms were 39 Gram-negative bacteria, 21 Gram-positive bacteria, and four fungi. There was a statistically significant risk of BSI between the variables: protocol for T-line-derived leukemia (Derived T Protocol) (p = 0.020), oral manifestations (p = 0.015), central venous catheter (p = 0.008), and bladder catheter (p = 0.004). BSI is a frequent event in ALL patients during the induction phase. The identification of these factors can allow the elaboration and improvement of strategies for the intensification of supportive care, prevention, and rapid treatment of infections.


Assuntos
Bacteriemia , Infecções Relacionadas a Cateter , Leucemia-Linfoma Linfoblástico de Células Precursoras , Sepse , Adolescente , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Infecções Relacionadas a Cateter/epidemiologia , Criança , Humanos , Incidência , Quimioterapia de Indução , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estudos Retrospectivos , Fatores de Risco
5.
Mol Biol Rep ; 47(9): 6949-6959, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32888124

RESUMO

Glioblastoma (GBM) is the most common primary malignant neoplasm of the central nervous system and, despite the standard therapy; the patients' prognoses remain dismal. The miRNA expression profiles have been associated with patient prognosis, suggesting that they may be helpful for tumor diagnosis and classification as well as predictive of tumor response to treatment. We described the microRNA expression profile of 29 primary GBM samples (9 pediatric GBMs) and 11 non-neoplastic white matter samples as controls (WM) by microarray analysis and we performed functional in vitro assays on these 2 most differentially expressed miRNAs. Hierarchical clustering analysis showed 3 distinct miRNA profiles, two of them in the GBM samples and a group consisting only of cerebral white matter. When adult and pediatric GBMs were compared to WM, 37 human miRNAs were found to be differentially expressed, with miR-10b-5p being the most overexpressed and miR-630 the most underexpressed. The overexpression of miR-630 was associated with reduced cell proliferation and invasion in the U87 GBM cell line, whereas the inhibition of miR-10b-5p reduced cell proliferation and colony formation in the U251 GBM cell line, suggesting that these miRNAs may act as tumor-suppressive and oncogenic miRNAs, respectively. The present study highlights the distinct epigenetic profiling of adult and pediatric GBMs and underscores the biological importance of mir-10b-5p and miR-630 for the pathobiology of these lethal tumors.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Glioblastoma/metabolismo , MicroRNAs/biossíntese , RNA Neoplásico/biossíntese , Adolescente , Adulto , Idoso , Linhagem Celular Tumoral , Criança , Pré-Escolar , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Pediatr Hematol Oncol ; 42(7): e641-e646, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-31613846

RESUMO

INTRODUCTION: Acute promyelocytic leukemia (APL) is currently considered a highly curable disease. However, an early death (ED) remains one of the main causes of APL treatment failure. PATIENTS AND METHODS: In this retrospective study, we aimed to analyze the clinical characteristics of 91 children and adolescents with APL, who were consecutively registered at the (name of institution removed) Children's Center from January 1, 1998 to December 31, 2017. Data were assessed for age, sex, ethnicity, body mass index percentile, initial white blood cell count, peripheral blood blast count, and platelet count, hemoglobin value, partial thromboplastin time, prothrombin time, fibrinogen level, serum creatinine level, APL morphology subtype (classic vs. hypogranular variant M3v), and FLT3 gene mutations. RESULTS: ED occurred in 12 of 91 (13.1%) patients and was mainly related to cerebral thromboembolism. Overall 66% of deaths occurred in the second week after diagnosis. ED was associated with white blood cell ≥10×10 cells/L (odds ratio of 8.44; 95% confidence interval [CI]=1.48-48.26; P=0.0016), initial promyelocytes ≥20×10/L (odds ratio of 9.29; 95% CI=2.45-35.8; P=0.001), morphologic subtype M3v (odds ratio of 3.63; 95% CI=1.04-12.64; P=0.043), and creatinine serum levels >0.7 mg/dL (odds ratio of 6.78; 95% CI=1.83-25.13; P=0.004). In multivariate analyses, ED was associated with initial peripheral promyelocytes ≥20×10 blasts/L and creatinine serum levels >0.7 mg/dL. CONCLUSIONS: EDs were mainly caused by thrombohemorrhagic events and occurred within the second week after diagnosis. High peripheral promyelocytes and creatinine levels were predictors of ED in APL.


Assuntos
Leucemia Promielocítica Aguda/mortalidade , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Retrospectivos
7.
Neurol Sci ; 41(3): 691-694, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31728854

RESUMO

BACKGROUND: Ependymoma (EPN) is the third most common childhood cancer of the central nervous system. RELA fusion-positive EPN accounts for approximately 70% of all childhood supratentorial tumors and shows the worst prognosis among the supratentorial EPNs. TP53 mutation is infrequent in RELA fusions EPNs. In the population from the Southern region of Brazil, there is a high incidence of the germline TP53 p.R337H mutation that predisposes carriers to develop early-onset tumors. However, despite this high incidence, the frequency of this mutation among EPN patients remains to be determined. Here, we investigated the presence of the TP53 p.R337H mutation in a larger cohort of pediatric EPNs of three institutions located in the state of São Paulo, Brazil. METHODS: The TP53 p.R337H mutation was screened by conventional RT-PCR and Sanger sequencing in 49 pediatric EPNs diagnosed during the period from 1995 to 2016. RESULTS: We described for the first time a case of a 5-year-old girl with RELA fusion EPN with a heterozygous TP53 p.R337H mutation. CONCLUSIONS: The present finding indicates that the TP53 p.R337H germline mutation is uncommon in patients with EPN in Brazil and screening of pediatric patients RELA fusion EPN may be informative to better understand the role of TP53 germline mutations in the development and prognosis of these tumors.


Assuntos
Ependimoma/genética , Neoplasias Supratentoriais/genética , Proteína Supressora de Tumor p53/genética , Brasil/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Ependimoma/epidemiologia , Feminino , Mutação em Linhagem Germinativa , Humanos , Masculino , Neoplasias Supratentoriais/epidemiologia , Fator de Transcrição RelA
8.
J Neurooncol ; 141(2): 373-382, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30570705

RESUMO

PURPOSES: Pilocytic astrocytoma (PA) is a low-grade neoplasm frequently found in childhood. PA is characterized by slow growth and a relatively good prognosis. Genetic mechanisms such as activation of MAPK, BRAF gene deregulation and neurofibromatosis type 1 (NF1) syndrome have been associated with PA development. Epigenetic signature and miRNA expression profile are providing new insights about different types of tumor, including PAs. METHODS: In the present study we evaluated global miRNA expression in 16 microdissected pediatric PA specimens, three NF1-associated PAs and 11 cerebral white matter (WM) samples by the microarray method. An additional cohort of 20 PAs was used to validate by qRT-PCR the expression of six miRNAs differentially expressed in the microarray data. RESULTS: Unsupervised hierarchical clustering analysis distinguished one cluster with nine PAs, including all NF1 cases and a second group consisting of the WM samples and seven PAs. Among 88 differentially expressed miRNAs between PAs and WM samples, the most underexpressed ones regulate classical pathways of tumorigenesis, while the most overexpressed miRNAs are related to pathways such as focal adhesion, P53 signaling pathway and gliomagenesis. The PAs/NF1 presented a subset of underexpressed miRNAs, which was also associated with known deregulated pathways in cancer such as cell cycle and hippo pathway. CONCLUSIONS: In summary, our data demonstrate that PA harbors at least two distinct miRNA signatures, including a subgroup of patients with NF1/PA lesions.


Assuntos
Astrocitoma/metabolismo , Neoplasias Encefálicas/metabolismo , Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Substância Branca/metabolismo , Adolescente , Astrocitoma/genética , Neoplasias Encefálicas/genética , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Masculino , Neurofibromatose 1/genética
9.
J Neurooncol ; 139(1): 33-42, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29582271

RESUMO

INTRODUCTION: Medulloblastoma (MB) is an embryonal tumour that originates from genetic deregulation of cerebellar developmental pathways and is classified into 4 molecular subgroups: SHH, WNT, group 3, and group 4. Hydroxymethylation levels progressively increases during cerebellum development suggesting a possibility of deregulation in MB pathogenesis. The aim of this study was to investigate global hydroxymethylation levels and changes in TET and IDH gene expression in MB samples compared to control cerebellum samples. METHODS: The methods utilized were qRT-PCR for gene expression, dot-blot and immunohistochemistry for global hydroxymethylation levels and sequencing for the investigation of IDH mutations. RESULTS: Our results show that global hydroxymethylation level was decreased in MB, and low 5hmC level was associated with the presence of metastasis. TET1 expression levels were decreased in the WNT subgroup, while TET3 expression levels were decreased in the SHH subgroup. Reduced TET3 expression levels were associated with the presence of events such as relapse and death. Higher expression of IDH1 was observed in MB group 3 samples, whereas no mutations were detected in exon 4 of IDH1 and IDH2. CONCLUSION: These findings suggest that reduction of global hydroxymethylation levels, an epigenetic event, may be important for MB development and/or maintenance, representing a possible target in this tumour and indicating a possible interaction of TET and IDH genes with the developmental pathways specifically activated in the MB subgroups. These genes could be specific targets and markers for each subgroup.


Assuntos
Neoplasias Cerebelares/metabolismo , Metilação de DNA , Isocitrato Desidrogenase/metabolismo , Meduloblastoma/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Cerebelares/genética , Cerebelo/metabolismo , Criança , Pré-Escolar , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Isocitrato Desidrogenase/genética , Masculino , Meduloblastoma/genética , Mutação , Proteínas Proto-Oncogênicas/genética
10.
Paediatr Perinat Epidemiol ; 32(6): 568-583, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30466188

RESUMO

BACKGROUND: Childhood cancer is a rare but leading cause of morbidity and mortality. Established risk factors, accounting for <10% of incidence, have been identified primarily from case-control studies. However, recall, selection and other potential biases impact interpretations particularly, for modest associations. A consortium of pregnancy and birth cohorts (I4C) was established to utilise prospective, pre-diagnostic exposure assessments and biological samples. METHODS: Eligibility criteria, follow-up methods and identification of paediatric cancer cases are described for cohorts currently participating or planning future participation. Also described are exposure assessments, harmonisation methods, biological samples potentially available for I4C research, the role of the I4C data and biospecimen coordinating centres and statistical approaches used in the pooled analyses. RESULTS: Currently, six cohorts recruited over six decades (1950s-2000s) contribute data on 388 120 mother-child pairs. Nine new cohorts from seven countries are anticipated to contribute data on 627 500 additional projected mother-child pairs within 5 years. Harmonised data currently includes over 20 "core" variables, with notable variability in mother/child characteristics within and across cohorts, reflecting in part, secular changes in pregnancy and birth characteristics over the decades. CONCLUSIONS: The I4C is the first cohort consortium to have published findings on paediatric cancer using harmonised variables across six pregnancy/birth cohorts. Projected increases in sample size, expanding sources of exposure data (eg, linkages to environmental and administrative databases), incorporation of biological measures to clarify exposures and underlying molecular mechanisms and forthcoming joint efforts to complement case-control studies offer the potential for breakthroughs in paediatric cancer aetiologic research.


Assuntos
Saúde da Criança , Exposição Ambiental/estatística & dados numéricos , Neoplasias/etiologia , Adolescente , Idade de Início , Viés , Criança , Pré-Escolar , Bases de Dados Factuais , Humanos , Lactente , Recém-Nascido , Estilo de Vida , Neoplasias/epidemiologia , Razão de Chances , Estudos Prospectivos , Fatores de Risco , Determinantes Sociais da Saúde/estatística & dados numéricos
11.
Cancer ; 123(16): 3150-3158, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28387921

RESUMO

BACKGROUND: The tumor protein p53 (TP53) arginine-to-histidine mutation at codon 337 (R337H) predisposes children to adrenocortical tumors (ACTs) and, rarely, to other childhood tumors, but its impact on adult cancer remains undetermined. The objective of this study was to investigate the frequency and types of cancer in relatives of children with ACT who carry the TP53 R337H mutation. METHODS: TP53 R337H testing was offered to relatives of probands with ACT. The parental lineage segregating the R337H mutation was identified in all families. The frequency and distribution of cancer types were compared according to R337H status. The authors' data also were compared with those publicly available for children with TP53 mutations other than R337H. RESULTS: The mean and median follow-up times for the probands with ACT were 11.2 years and 9.7 years (range, 3-32 years), respectively. During this time, cancer was diagnosed in 12 of 81 first-degree relatives (14.8%) carrying the R337H mutation but in only 1 of 94 noncarriers (1.1%; P = .0022). At age 45 years, the cumulative risk of cancer was 21% (95% confidence interval, 5%-33%) in carriers and 2% (95% confidence interval, 0%-4%) in noncarriers (P = .008). The frequency of cancer was higher in the R337H segregating lineages than in the nonsegregating lineages (249 of 1410 vs 66 of 984 individuals; P < .001). Breast and gastric cancer were the most common types. CONCLUSIONS: TP53 R337H carriers have a lifelong predisposition to cancer with a bimodal age distribution: 1 peak, represented by ACT, occurs in the first decade of life, and another peak of diverse cancer types occurs in the fifth decade. The current findings have implications for genetic counseling and surveillance of R337H carriers. Cancer 2017;123:3150-58. © 2017 American Cancer Society.


Assuntos
Neoplasias do Córtex Suprarrenal/genética , Neoplasias da Mama/genética , Neoplasias Gástricas/genética , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Brasil , Criança , Pré-Escolar , Família , Feminino , Predisposição Genética para Doença , Heterozigoto , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Neoplasias/genética , Adulto Jovem
12.
Proc Natl Acad Sci U S A ; 111(51): E5564-73, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25512523

RESUMO

Osteosarcoma is the most common primary bone tumor, yet there have been no substantial advances in treatment or survival in three decades. We examined 59 tumor/normal pairs by whole-exome, whole-genome, and RNA-sequencing. Only the TP53 gene was mutated at significant frequency across all samples. The mean nonsilent somatic mutation rate was 1.2 mutations per megabase, and there was a median of 230 somatic rearrangements per tumor. Complex chains of rearrangements and localized hypermutation were detected in almost all cases. Given the intertumor heterogeneity, the extent of genomic instability, and the difficulty in acquiring a large sample size in a rare tumor, we used several methods to identify genomic events contributing to osteosarcoma survival. Pathway analysis, a heuristic analytic algorithm, a comparative oncology approach, and an shRNA screen converged on the phosphatidylinositol 3-kinase/mammalian target of rapamycin (PI3K/mTOR) pathway as a central vulnerability for therapeutic exploitation in osteosarcoma. Osteosarcoma cell lines are responsive to pharmacologic and genetic inhibition of the PI3K/mTOR pathway both in vitro and in vivo.


Assuntos
Neoplasias Ósseas/metabolismo , Genoma Humano , Osteossarcoma/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Proliferação de Células , Heterogeneidade Genética , Mutação em Linhagem Germinativa , Humanos , Osteossarcoma/genética , Osteossarcoma/patologia , Proteína Supressora de Tumor p53/genética
14.
Br J Haematol ; 171(5): 736-51, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26456771

RESUMO

Lymphotoxin-mediated activation of the lymphotoxin-ß receptor (LTßR; LTBR) has been implicated in cancer, but its role in T-cell acute lymphoblastic leukaemia (T-ALL) has remained elusive. Here we show that the genes encoding lymphotoxin (LT)-α and LTß (LTA, LTB) are expressed in T-ALL patient samples, mostly of the TAL/LMO molecular subtype, and in the TEL-JAK2 transgenic mouse model of cortical/mature T-ALL (Lta, Ltb). In these mice, expression of Lta and Ltb is elevated in early stage T-ALL. Surface LTα1 ß2 protein is expressed in primary mouse T-ALL cells, but only in the absence of microenvironmental LTßR interaction. Indeed, surface LT expression is suppressed in leukaemic cells contacting Ltbr-expressing but not Ltbr-deficient stromal cells, both in vitro and in vivo, thus indicating that dynamic surface LT expression in leukaemic cells depends on interaction with its receptor. Supporting the notion that LT signalling plays a role in T-ALL, inactivation of Ltbr results in a significant delay in TEL-JAK2-induced leukaemia onset. Moreover, young asymptomatic TEL-JAK2;Ltbr(-/-) mice present markedly less leukaemic thymocytes than age-matched TEL-JAK2;Ltbr(+/+) mice and interference with LTßR function at this early stage delayed T-ALL development. We conclude that LT expression by T-ALL cells activates LTßR signalling in thymic stromal cells, thus promoting leukaemogenesis.


Assuntos
Receptor beta de Linfotoxina/fisiologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Animais , Carcinogênese/genética , Linhagem Celular Tumoral , Linhagem da Célula/genética , Expressão Gênica/genética , Humanos , Imunofenotipagem , Janus Quinase 2/genética , Receptor beta de Linfotoxina/genética , Receptor beta de Linfotoxina/metabolismo , Camundongos Knockout , Camundongos Transgênicos , Dados de Sequência Molecular , Transdução de Sinais , Microambiente Tumoral/genética
15.
Pediatr Hematol Oncol ; 32(5): 322-30, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26086683

RESUMO

OBJECTIVE: to investigate the associations of oral microbiota, leucocytes count, neutrophil count, platelet counts and hemoglobin level, and the severity of oral mucositis in pediatric patients with acute lymphoblastic leukemia (ALL) receiving chemotherapy. MATERIALS AND METHODS: 71 prospective patients were included. Analyses of oral microbiota and blood sample were conducted on days 14 (D14) and 56 (D56) of the Brazilian GBTLI-99 treatment protocol. Herpes simplex virus (HSV) identification was performed by PCR followed by DNA sequencing analysis. Bacteria and fungi identification was obtained by standard microbiological culture tests. RESULTS: 103 episodes of mucositis occurred, being 65 at D14 and 38 at D56. Most cases positive for herpes viral DNA sequences were identified as HSV-1. At D14, we found a significant association between the severity of mucositis and presence of HSV-1 (p = 0.0347), Candida spp. (p = 0.0078), and low platelet count (p = 0.0064). At D56, we found a significant association between the severity of mucositis and the presence of HSV-1 (p = 0.0317), previous HSV-1 presence on D14 (p < 0.0001) and neutrophil count (p = 0.0211). CLINICAL RELEVANCE: the identification of risk factors for mucositis in children and adolescents may contribute to the development of new strategies for prevention and/or treatment, reducing the complications associated with this condition. CONCLUSIONS: the presence of HSV, platelet count, and Candida spp. presence at D14 of ALL induction treatment is associated with increased severity of mucositis in children and adolescents. At D56 of ALL treatment, mucositis severity was associated with neutrophil count, HSV presence, and previous presence of HSV (at D14).


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Candida , Candidíase/epidemiologia , Herpes Simples/epidemiologia , Herpesvirus Humano 1 , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Estomatite/epidemiologia , Adolescente , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Brasil/epidemiologia , Candidíase/induzido quimicamente , Criança , Pré-Escolar , Feminino , Herpes Simples/induzido quimicamente , Humanos , Lactente , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/epidemiologia , Estudos Prospectivos , Estomatite/induzido quimicamente
17.
Clin Endocrinol (Oxf) ; 81(4): 503-10, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24717047

RESUMO

CONTEXT: The role of planar cell polarity (Wnt/PCP) and calcium-dependent (Wnt/Ca) noncanonical Wnt pathways in adrenocortical tumours (ACTs) is unknown. OBJECTIVES: To investigate the gene expression of Wnt/PCP and Wnt/Ca pathways and its association with TP53 p.R337H and CTNNB1 mutations in paediatric and adult ACTs and to correlate these findings with clinical outcome. PATIENTS: Expression of noncanonical Wnt-related genes was evaluated in 91 ACTs (66 children and 25 adults) by qPCR and the expression of beta-catenin, P53 and protein effectors of Wnt/Ca (NFAT) and Wnt/PCP (JNK) by immunohistochemistry. TP53 and CTNNB1 genes were sequenced. RESULTS: TP53 p.R337H mutation frequency was higher in children (86% vs 28%), while CTNNB1 mutation was higher in adults (32% vs 6%). Mortality was higher in adults harbouring TP53 p.R337H and in children with CTNNB1 mutations. Overexpression of WNT5A, Wnt/Ca ligand, was observed in children and adults. Overexpression of MAPK8 and underexpression of PRICKLE, Wnt/PCP mediators, were observed in paediatric but not in adult cases. Cytoplasmic/nuclear beta-catenin and P53 accumulation was observed in the majority of paediatric and adult ACTs as well as NFAT and JNK. Overexpression of MAPK8 and underexpression of PRICKLE were associated with mortality in children, while overexpression of WNT5A and underexpression of PRICKLE were associated with mortality in adults. CONCLUSIONS: In our study, TP53 p.R337H and CTNNB1 mutations correlated with poor prognosis in adults and children, respectively. We demonstrate, for the first time, the activation of Wnt/PCP and Wnt/Ca noncanonical pathway genes, and their association with poor outcome in children and adults, suggesting their putative involvement in ACTs aggressiveness.


Assuntos
Neoplasias do Córtex Suprarrenal/metabolismo , Via de Sinalização Wnt/fisiologia , Adolescente , Neoplasias do Córtex Suprarrenal/genética , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Via de Sinalização Wnt/genética , Adulto Jovem , beta Catenina/genética , beta Catenina/metabolismo
18.
Pediatr Blood Cancer ; 61(11): 1940-8, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25156210

RESUMO

BACKGROUND: Low expression of HLA class II antigens has been associated with more aggressive disease in several human malignancies including adult adrenocortical tumors (ACT), but their clinical relevance in pediatric ACT needs to be investigated. PROCEDURE: This study analyzed the expression profile of three class II histocompatibility genes (HLA-DRA, HLA-DPA1, and HLA-DPB1) in 58 consecutive pediatric ACT (13 adenomas and 45 carcinomas) by quantitative real time PCR and their association with clinical and biological features. HLA-DPA1 protein level was determined by immunohistochemistry. RESULTS: A significant association (P < 0.01) was observed between lower expression levels of the three genes analyzed and poor prognostic factors such as age ≥ 4 years, tumor size ≥ 200 cm(3), tumor weight ≥ 100 g, and metastatic disease; the presence of an unfavorable event and death. Underexpression of the HLA-DRA, HLA-DPA1, and HLA-DPB1 genes were associated with lower 5-year event-free survival (EFS) (P = 0.017, P < 0.001, and P = 0.017, respectively). Cox multivariate analysis showed that HLA-DPA1 was an independent prognostic factor (P = 0.029) when analyzed in association with stage IV, age and tumor size. Significantly lower EFS was also observed in patients with negative/weak immunostaining for HLA-DPA1 (P = 0.002). Similar results were observed when only patients classified as having carcinomas were analyzed. CONCLUSION: Our results suggest that lower expression of HLA-DRA, HLA-DPA1, and HLA-DPB1 genes may contribute to more aggressive disease in pediatric ACT. HLA-DPA1 immunostaining may represent potential aggressiveness marker in this tumor.


Assuntos
Neoplasias do Córtex Suprarrenal/imunologia , Cadeias alfa de HLA-DP/genética , Cadeias beta de HLA-DP/genética , Cadeias alfa de HLA-DR/genética , Adolescente , Neoplasias do Córtex Suprarrenal/mortalidade , Neoplasias do Córtex Suprarrenal/patologia , Criança , Pré-Escolar , Feminino , Cadeias alfa de HLA-DP/análise , Cadeias beta de HLA-DP/análise , Cadeias alfa de HLA-DR/análise , Humanos , Lactente , Masculino , Prognóstico
19.
Cancers (Basel) ; 16(6)2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38539429

RESUMO

Pediatric adrenocortical tumors (ACTs) are rare, highly heterogeneous neoplasms with limited therapeutic options, making the investigation of new targets with potential therapeutic or prognostic purposes urgent. The PRKAB2 gene produces one of the subunits of the AMP-activated protein kinase (AMPK) complex and has been associated with cancer. However, little is known about the role AMPK plays in ACTs. We have evaluated how PRKAB2 is associated with clinical and biological characteristics in 63 pediatric patients with ACTs and conducted in vitro studies on the human NCI-H295R ACC cell line. An analysis of our cohort and the public ACC pediatric dataset GSE76019 showed that lower PRKAB2 expression was associated with relapse, death, metastasis, and lower event-free and overall survival rates. Multivariate analysis showed that PRKAB2 expression was an independent prognostic factor when associated with age, tumor weight and volume, and metastasis. In vitro tests on NCI-H295R cells demonstrated that Rottlerin, a drug that can activate AMPK, modulated several pathways in NCI-H295R cells, including AMPK/mTOR, Wnt/ß-catenin, SKP2, HH, MAPK, NFKB, and TNF. Treatment with Rottlerin decreased cell proliferation and migration, clonogenic capacity, and steroid production. Together, these results suggest that PRKAB2 is a potential prognostic marker in pediatric ACTs, and that Rottlerin is promising for investigating drugs that can act against ACTs.

20.
Eur J Endocrinol ; 190(4): G15-G24, 2024 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-38552173

RESUMO

OBJECTIVE: Mitotane is an important cornerstone in the treatment of pediatric adrenal cortical tumors (pACC), but experience with the drug in the pediatric age group is still limited and current practice is not guided by robust evidence. Therefore, we have compiled international consensus statements from pACC experts on mitotane indications, therapy, and management of adverse effects. METHODS: A Delphi method with 3 rounds of questionnaires within the pACC expert consortium of the international network groups European Network for the Study of Adrenal Tumors pediatric working group (ENSAT-PACT) and International Consortium of pediatric adrenocortical tumors (ICPACT) was used to create 21 final consensus statements. RESULTS: We divided the statements into 4 groups: environment, indications, therapy, and adverse effects. We reached a clear consensus for mitotane treatment for advanced pACC with stages III and IV and with incomplete resection/tumor spillage. For stage II patients, mitotane is not generally indicated. The timing of initiating mitotane therapy depends on the clinical condition of the patient and the setting of the planned therapy. We recommend a starting dose of 50 mg/kg/d (1500 mg/m²/d) which can be increased up to 4000 mg/m2/d. Blood levels should range between 14 and 20 mg/L. Duration of mitotane treatment depends on the clinical risk profile and tolerability. Mitotane treatment causes adrenal insufficiency in virtually all patients requiring glucocorticoid replacement shortly after beginning. As the spectrum of adverse effects of mitotane is wide-ranging and can be life-threatening, frequent clinical and neurological examinations (every 2-4 weeks), along with evaluation and assessment of laboratory values, are required. CONCLUSIONS: The Delphi method enabled us to propose an expert consensus statement, which may guide clinicians, further adapted by local norms and the individual patient setting. In order to generate evidence, well-constructed studies should be the focus of future efforts.


Assuntos
Neoplasias do Córtex Suprarrenal , Carcinoma Adrenocortical , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Humanos , Criança , Mitotano/efeitos adversos , Carcinoma Adrenocortical/tratamento farmacológico , Carcinoma Adrenocortical/patologia , Antineoplásicos Hormonais/efeitos adversos , Neoplasias do Córtex Suprarrenal/tratamento farmacológico , Neoplasias do Córtex Suprarrenal/patologia
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