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1.
Neurogenetics ; 25(3): 287-291, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38652341

RESUMO

Aminoacyl-tRNA synthetases (ARSs) aminoacylate tRNA molecules with their cognate amino acid, enabling information transmission and providing substrates for protein biosynthesis. They also take part in nontranslational functions, mediated by the presence of other proteins domains. Mutations in ARS genes have been described as responsive to numerous factors, including neurological, autoimmune, and oncological. Variants of the ARS genes, both in heterozygosity and homozygosity, have been reported to be responsible for different pathological pictures in humankind. We present the case of a patient referred in infancy for failure to thrive and acquired microcephaly (head circumference: -5 SD). During follow-up we highlighted: dysphagia (which became increasingly severe until it became incompatible with oral feeding, with gastrostomy implantation, resulting in resolution of feeding difficulties), strabismus, hypotonia. NCV (Nerve Conduction Velocity) showed four limbs neuropathy, neurophysiological examination performed at 2 years of age mainly sensory and demyelinating. Exome sequencing (ES) was performed, detecting two novel compound heterozygous variants in the NARS1 gene (OMIM *108410): NM_004539:c.[662 A > G]; [1155dup], p.[(Asn221Ser)]; [(Arg386Thrfs*19)], inherited from mother and father respectively. In this article, we would like to focus on the presence of progressive dysphagia and severe neurodevelopmental disorder, associated with two novel variants in the NARS1 gene.


Assuntos
Transtornos de Deglutição , Transtornos do Neurodesenvolvimento , Humanos , Transtornos de Deglutição/genética , Transtornos de Deglutição/diagnóstico , Transtornos do Neurodesenvolvimento/genética , Transtornos do Neurodesenvolvimento/diagnóstico , Aminoacil-tRNA Sintetases/genética , Masculino , Mutação/genética , Lactente , Pré-Escolar , Feminino
2.
Pediatr Infect Dis J ; 43(6): 543-549, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38377462

RESUMO

BACKGROUND: The incidence of pediatric inflammatory bowel disease is increasing. tumor necrosis factor alpha inhibitors medicines improved the prognosis of affected subjects. Nonetheless, a proportion of patients do not respond or lose response to treatment. Newer biologics, like ustekinumab, have been approved for adults. The pediatric off-label use of these drugs is increasing, despite limited safety evidence. We report a case of disseminated mycobacterial infection (MI) presenting with reactive polyarthritis (Poncet's disease, PD) in a girl with Crohn's disease receiving various immunosuppressants, including ustekinumab. CASE REPORT: A 12-year-old girl with Crohn's disease was admitted for acute-onset migratory polyarthritis of large and small joints and opioid-resistant pain. She had recently received adalimumab and methotrexate and was currently under treatment with ustekinumab. She was vaccinated with Bacillus Calmette-Guérin and screened for tuberculosis before starting immunosuppressants. Interferon-gamma release assay, Mantoux test and chest computed tomography scan were negative. Disseminated MI with PD was diagnosed following positive cultures for Mycobacterium tuberculosis complex in blood and intestinal biopsies (with negative in synovial fluid and gastric aspirate). Whole-exome sequencing did not identify any genetic susceptibility to MI. Antituberculosis treatment eradicated MI. CONCLUSIONS: Children with inflammatory bowel disease receiving combination immunosuppressive treatments including tumor necrosis factor alpha inhibitors and anti-IL-12/23 agents are at higher risk for MI. Disseminated MI should be considered and ruled out in these patients when presenting with pulmonary, extrapulmonary or unusual clinical manifestations, like PD. The collection of multiple specimens (including intestinal biopsies) for mycobacterial culture is recommended when mycobacterial disease is suspected.


Assuntos
Doença de Crohn , Imunossupressores , Ustekinumab , Humanos , Feminino , Doença de Crohn/tratamento farmacológico , Doença de Crohn/complicações , Criança , Ustekinumab/uso terapêutico , Ustekinumab/efeitos adversos , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Artrite Reativa/tratamento farmacológico , Artrite Reativa/microbiologia , Infecções por Mycobacterium/tratamento farmacológico
4.
Front Pediatr ; 9: 703056, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34692603

RESUMO

Nodular lymphoid hyperplasia (NLH) is a lymphoproliferative disease caused by non-clonal expansion of lymphoid cells in the gut mucosa. Little is known about the pathogenesis of NLH, which is often disregarded as an insignificant or para-physiologic phenomenon. We present the case of a girl with isolated diffuse NLH (extending from the stomach to the rectum) caused by activated PI3Kδ syndrome (APDS) due to the novel p.Glu525Gly variant in PIK3CD. The gain-of-function effect of the variant was confirmed by demonstration of over activation of the Akt/mTOR pathway in the patient's cells. APDS diagnosis led to treatment with sirolimus, which resulted in the complete remission of NLH and in the prevention of extra intestinal complications. In conclusion, we identify APDS as a novel cause of isolated NLH and suggest that patients with severe pan-enteric NLH should be screened for this disorder that may not be apparent on first-line immunological testing.

5.
Hum Genet ; 140(9): 1299-1312, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34185153

RESUMO

Genetic defects of innate immunity impairing intestinal bacterial sensing are linked to the development of Inflammatory Bowel Disease (IBD). Although much evidence supports a role of the intestinal virome in gut homeostasis, most studies focus on intestinal viral composition rather than on host intestinal viral sensitivity. To demonstrate the association between the development of Very Early Onset IBD (VEOIBD) and variants in the IFIH1 gene which encodes MDA5, a key cytosolic sensor for viral nucleic acids. Whole exome sequencing (WES) was performed in two independent cohorts of children with VEOIBD enrolled in Italy (n = 18) and USA (n = 24). Luciferase reporter assays were employed to assess MDA5 activity. An enrichment analysis was performed on IFIH1 comparing 42 VEOIBD probands with 1527 unrelated individuals without gastrointestinal or immunological issues. We identified rare, likely loss-of-function (LoF), IFIH1 variants in eight patients with VEOIBD from a combined cohort of 42 children. One subject, carrying a homozygous truncating variant resulting in complete LoF, experienced neonatal-onset, pan-gastrointestinal, IBD-like enteropathy plus multiple infectious episodes. The remaining seven subjects, affected by VEOIBD without immunodeficiency, were carriers of one LoF variant in IFIH1. Among these, two patients also carried a second hypomorphic variant, with partial function apparent when MDA5 was weakly stimulated. Furthermore, IFIH1 variants were significantly enriched in children with VEOIBD as compared to controls (p = 0.007). Complete and partial MDA5 deficiency is associated with VEOIBD with variable penetrance and expressivity, suggesting a role for impaired intestinal viral sensing in IBD pathogenesis.


Assuntos
Doenças Inflamatórias Intestinais/genética , Helicase IFIH1 Induzida por Interferon/genética , Mutação com Perda de Função , Pré-Escolar , Feminino , Humanos , Lactente , Itália , Masculino , Sequenciamento Completo do Genoma
6.
Sci Rep ; 11(1): 5945, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33723309

RESUMO

CARMIL2 is required for CD28-mediated co-stimulation of NF-κB signaling in T cells and its deficiency has been associated with primary immunodeficiency and, recently, very early onset inflammatory bowel disease (IBD). Here we describe the identification of novel biallelic CARMIL2 variants in three patients presenting with pediatric-onset IBD and in one with autoimmune polyendocrine syndrome (APS). None manifested overt clinical signs of immunodeficiency before their diagnosis. The first patient presented with very early onset IBD. His brother was found homozygous for the same CARMIL2 null variant and diagnosed with APS. Two other IBD patients were found homozygous for a nonsense and a missense CARMIL2 variant, respectively, and they both experienced a complicated postoperative course marked by severe infections. Immunostaining of bowel biopsies showed reduced CARMIL2 expression in all the three patients with IBD. Western blot and immunofluorescence of transfected cells revealed an altered expression pattern of the missense variant. Our work expands the genotypic and phenotypic spectrum of CARMIL2 deficiency, which can present with either IBD or APS, aside from classic immunodeficiency manifestations. CARMIL2 should be included in the diagnostic work-up of patients with suspected monogenic IBD.


Assuntos
Predisposição Genética para Doença , Doenças Inflamatórias Intestinais/etiologia , Mutação com Perda de Função , Proteínas dos Microfilamentos/genética , Fatores Etários , Alelos , Criança , Pré-Escolar , Colonoscopia , Consanguinidade , Análise Mutacional de DNA , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Imuno-Histoquímica , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Masculino , Linhagem
7.
JIMD Rep ; 54(1): 25-31, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32685347

RESUMO

Glycerol-3-phosphate dehydrogenase 1 deficiency is a rare autosomal recessive disorder caused by mutations in the GPD1 gene (GPD1; OMIM*138420). Very few cases are reported in literature. It usually manifests in early infancy with transient hypertriglyceridemia, hepatomegaly, steatosis, and fibrosis. We report the case of a 16-year-old boy followed since the age of 1 year for hepatomegaly, elevated liver enzymes, and persistent hypertriglyceridemia. Abdominal ultrasound showed diffuse liver echogenicity and liver biopsy disclosed cirrhosis with micro and macrovesicular steatosis. Next-generation sequencing for metabolic and genetic liver diseases was conducted with the identification of the homozygous mutation c.895G>A in GPD1 gene resulting in the aminocidic substitution p.G299R. Considering the persistent and progressive increase of plasma triglycerides, fenofibrate treatment was started at 15 years of age allowing triglyceride level reduction in the following 1-year follow-up.

8.
Biomed Rep ; 7(3): 241-246, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28811895

RESUMO

The aim of the present study was to report a novel mutation in the retinoschisin 1 (RS1) gene in a Caucasian family affected by X-linked juvenile retinoschisis (XLRS) and to describe the long-term modification of retinal structure. Two brothers with an early onset maculopathy were diagnosed with XLRS. Fundus photography, fluorescein angiography, spectral domain optical coherence tomography and electroretinogram analyses were performed. Their sister was also examined. All subjects were screened for mutations in the RS1 gene. XLRS patients demonstrated a marked reduction of best-corrected visual acuity. SD-OCT scans reported a cystic degeneration primarily involving the inner nuclear layer, though some cysts were detected in the outer plexiform layer and in the ganglion cell layer. During the ten-year follow-up, a progressive retinal thickening and coalescence of the cysts was observed. Genetic testing revealed a novel mutation (p.Ile212Asn) in the RS1 gene in both XLRS patients, whereas their sister was not a genetic carrier. Several mutations of the RS1 gene were recognized to be responsible for XLRS. Although the correspondence between genotype and phenotype is still under debate, is reasonable that siblings affected by XLRS could share other genetic and/or epigenetic factors capable to influence clinical course of the disease.

9.
Acta Ophthalmol ; 93(6): e451-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25402348

RESUMO

PURPOSE: To investigate whether genetic and non-genetic risk factors influence 12-month response to ranibizumab treatment for exudative age-related macular degeneration (AMD). METHODS: A cohort of 94 Caucasian patients with unilateral exudative AMD received intravitreal ranibizumab. After a three-injection loading phase, a PRN regimen was followed. Patients were genotyped for three single-nucleotide polymorphisms: CFH rs1061170, ARMS2 rs10490924 and C3 rs2230199. Non-genetic risk factors [choroidal neovascularization (CNV) phenotype, smoking habit, hypertension and body mass index] were considered. The selected end-point was the 12-month variation of number of ETDRS letters. RESULTS: Complement factor H (CFH) risk alleles, smoking history and arterial hypertension each independently influenced treatment response, with worse 12-month BCVA outcomes (p = 0.036, 0.037, 0.043, respectively). A significant cumulative effect of these risk factors was also observed: patients homozygous for the CFH risk alleles and with a positive smoking history showed a mean loss of 8.0 ETDRS letters (p = 0.010). Patients with CFH risk alleles, smoking history and hypertension had a mean loss of 13.9 ETDRS letters (p = 0.013). CNV phenotypes did not influence visual outcomes, nor were they associated with other genetic/non-genetic risk factors. CONCLUSIONS: Complement factor H risk alleles, smoking history and hypertension affect the mid-term response to ranibizumab in exudative AMD.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Farmacogenética , Polimorfismo de Nucleotídeo Único , Ranibizumab/uso terapêutico , Degeneração Macular Exsudativa/tratamento farmacológico , Degeneração Macular Exsudativa/genética , Idoso , Idoso de 80 Anos ou mais , Complemento C3/genética , Fator H do Complemento/genética , Feminino , Técnicas de Genotipagem , Humanos , Hipertensão/complicações , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Proteínas/genética , Fatores de Risco , Fumar/efeitos adversos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Acuidade Visual/fisiologia , Degeneração Macular Exsudativa/fisiopatologia
10.
Gut ; 63(2): 300-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23525603

RESUMO

OBJECTIVE: Necrotising enterocolitis (NEC) remains one of the primary causes of morbidity and mortality in neonates and alternative strategies are needed. Stem cells have become a therapeutic option for other intestinal diseases, which share some features with NEC. We tested the hypothesis that amniotic fluid stem (AFS) cells exerted a beneficial effect in a neonatal rat model of NEC. DESIGN: Rats intraperitoneally injected with AFS cells and their controls (bone marrow mesenchymal stem cells, myoblast) were analysed for survival, behaviour, bowel imaging (MRI scan), histology, bowel absorption and motility, immunofluorescence for AFS cell detection, degree of gut inflammation (myeloperoxidase and malondialdehyde), and enterocyte apoptosis and proliferation. RESULTS: AFS cells integrated in the bowel wall and improved rat survival and clinical conditions, decreased NEC incidence and macroscopic gut damage, improved intestinal function, decreased bowel inflammation, increased enterocyte proliferation and reduced apoptosis. The beneficial effect was achieved via modulation of stromal cells expressing cyclooxygenase 2 in the lamina propria, as shown by survival studies using selective and non-selective cyclooxygenase 2 inhibitors. Interestingly, AFS cells differentially expressed genes of the Wnt/ß-catenin pathway, which regulate intestinal epithelial stem cell function and cell migration and growth factors known to maintain gut epithelial integrity and reduce mucosal injury. CONCLUSIONS: We demonstrated here for the first time that AFS cells injected in an established model of NEC improve survival, clinical status, gut structure and function. Understanding the mechanism of this effect may help us to develop new cellular or pharmacological therapies for infants with NEC.


Assuntos
Líquido Amniótico/citologia , Inibidores de Ciclo-Oxigenase 2/farmacologia , Ciclo-Oxigenase 2/metabolismo , Enterocolite Necrosante/terapia , Enterócitos/metabolismo , Mucosa Intestinal/enzimologia , Regeneração/fisiologia , Transplante de Células-Tronco , Células-Tronco/fisiologia , Animais , Apoptose , Enterocolite Necrosante/enzimologia , Imunofluorescência , Imageamento por Ressonância Magnética , Ratos , Taxa de Sobrevida
11.
J Neuroimmunol ; 233(1-2): 97-105, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21216016

RESUMO

It is well known that the cannabinoid system has a significant role in the regulation of the immune responses. Cannabinoid receptors CB1 and CB2 are expressed on T lymphocytes and mediate the immunomodulatory effects of cannabinoids on T cell functions. Here we show that the treatment of proteolipid protein (PLP)139-151-specific T cells with SR141716A, a CB1 inverse agonist and prototype of the diarylpyrazoles series, induced a strong inhibition of firm adhesion in inflamed brain venules in intravital microscopy experiments. In contrast, SR144528, a potent CB2 inverse agonist, had no significant effect on both rolling and arrest of activated T cells. In addition, two analogs of SR141716A and CB1 inverse agonists, AM251 and AM281 inhibited encephalitogenic T cell adhesion suggesting that selective CB1 inverse agonism interfere with lymphocyte trafficking in the CNS. Flow cytometry experiments showed that CB1 inverse agonists have no effect on adhesion molecule expression suggesting that CB1 blockade interferes with signal transduction pathways controlling T cell adhesion in inflamed brain venules. In addition, integrin clustering was not altered after treatment with CB1 inverse agonists suggesting that adhesion blockade is not due to the modulation of integrin valency. Notably, the inhibitory effect exerted by AM251 and AM281 on the adhesive interactions was completely reverted in the presence of protein kinase A (PKA) inhibitor H89, suggesting that cAMP and PKA activation play a key role in the adhesion blockade mediated by CB1 inverse agonists. To further strengthen these results and unveil a previously unknown inhibitory role of cAMP on activated T cell adhesion in vivo in the context of CNS inflammation, we showed that intracellular increase of cAMP induced by treatment with Bt2cAMP, a permeable analog of cAMP, and phosphodiesterase (PDE) inhibitor theophylline efficiently blocked the arrest of encephalitogenic T cells in inflamed brain venules. Our data show that modulation of CB1 function has anti-inflammatory effects and suggests that inverse agonism of CB1 block signal transduction mechanisms controlling encephalitogenic T cells adhesion in inflamed brain venules by a PKA-dependent mechanism.


Assuntos
Encéfalo/irrigação sanguínea , Proteínas Quinases Dependentes de AMP Cíclico/fisiologia , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/fisiologia , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/patologia , Animais , Encéfalo/enzimologia , Encéfalo/patologia , Adesão Celular/imunologia , Células Cultivadas , Modelos Animais de Doenças , Feminino , Camundongos , Subpopulações de Linfócitos T/enzimologia , Vênulas/enzimologia , Vênulas/imunologia , Vênulas/patologia
12.
J Gastroenterol ; 45(1): 68-76, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19730968

RESUMO

BACKGROUND: The endocannabinoid system (EC) has emerged as a crucial mediator in a variety of pathophysiological conditions. AIMS: To evaluate: (1) whether the EC system is activated in the livers of patients with primary biliary cirrhosis (PBC); (2) if genetic variations in human EC receptor genes (CB1 and CB2) may be associated with a different phenotypic expression of the disease and response to therapy. METHODS: The expression of CB1 and CB2 receptors was studied by immunohistochemistry in liver biopsy specimens from 13 patients with PBC, and CB1 and CB2 mRNA expression was studied by real-time polymerase chain reaction testing (RT-PCR) in liver samples. In addition, genetic polymorphisms in the EC receptor gene were sought in 68 patients with PBC from Italy, 84 patients who were residents of the United States (US), and 70 controls matched for sex, age, and for geographical area with the Italian PBC patients. Genomic DNA was extracted from peripheral venous blood leucocytes with standard methods. PCR was used to amplify the coding regions of the CB1 and CB2 genes with specific primers. RESULTS: CB1 was markedly expressed in hepatocytes and biliary epithelial cells in the livers of patients with PBC; conversely in control liver samples, it was virtually absent. CB2 was expressed in hepatocytes and in cholangiocytes, whereas it was absent from mesenchymal cells. The mRNA of both CB1 and CB2 was detected in the PBC liver samples, as demonstrated by RT-PCR. The CB1 polymorphism (1359 G/A) was present in 26.5% of Italian patients, in 22.9% of healthy controls, and in 27.4% of patients from the US (p = n.s.). The CB2 polymorphism (188-189 AA/GG) was present in 24.4 versus 30.4% of Italian and US patients with PBC, respectively, and in 28.0% of Italian controls samples (p = n.s.). Logistic regression analysis showed that advanced histological stage and the lack of response to ursodeoxycholic acid treatment were significantly correlated with the CB1 polymorphism. CONCLUSIONS: The EC system is markedly up-regulated in the livers of patients with PBC and it may exert a role regulating adaptive mechanisms in cholestasis.


Assuntos
Cirrose Hepática Biliar/genética , Fígado/patologia , Receptor CB1 de Canabinoide/genética , Receptor CB2 de Canabinoide/genética , Adulto , Idoso , Biópsia , Estudos de Casos e Controles , Feminino , Humanos , Itália , Fígado/citologia , Cirrose Hepática Biliar/patologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estados Unidos , Regulação para Cima
13.
Cancer Chemother Pharmacol ; 64(6): 1195-200, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19306093

RESUMO

PURPOSE: To investigate the allelic status of the thymidylate synthetase (TYMS) gene, located at chromosome band 18p11.32, in renal cell carcinoma (RCC). TYMS is a key target of the 5-fluorouracil (5-FU)-based class of drugs, frequently considered in combination therapies in advanced RCC. TYMS variants, such as the TYMS polymorphic 5'-untranslated region variable number tandem repeat sequence (VNTR), are under investigation to guide 5-FU treatment. Yet, no information is available with regard to changes in TYMS allele frequencies in RCC malignances. METHODS: Blood and matched tumor samples were collected from 41 histological proven clear cell RCC affected patients (30 males, 11 females.). TYMS VNTR genotype was first determined in blood to identify heterozygotes employing PCR techniques. To evaluate for allelic imbalance, fragment analysis was performed both in blood and matched tumor DNA of the heterozygote patients. Microsatellite analysis, employing the markers D18S59 and D18S476 mapping, respectively, at the TYMS locus (18p11.32) and 1.5 Mb downstream of the TYMS gene sequence (18p11.31), was performed to confirm TYMS allelic imbalance in tumors. RESULTS: Germ-line TYMS VNTR distribution was: 2R/2R (19.5%), TYMS 2R/3R (36.6%) and TYMS 3R/3R (43.9%). Allelic imbalance for the TYMS tandem repeat region was detected in 26.6% of the heterozygote patients. Microsatellite analysis confirmed the allelic imbalance detected by TYMS VNTR analysis and revealed that the overall frequence of allelic imbalance of chromosome band 18p11.32 was 35%, while the overall allelic imbalance of chromosome band 18p11.31 was 28%. CONCLUSIONS: By focusing on the TYMS polymorphic variants in renal cancer, we here provide evidence, to our knowledge, for the first time showing loss of 18p11.32 and 18p11.31 in renal cell carcinomas. As allelic imbalances involving TYMS locus may be an important variable affecting 5-FU responsiveness, this study may contribute to explain different responses of advanced RCC in combined chemotherapeutic regimens incorporating fluoropyridines.


Assuntos
Desequilíbrio Alélico/genética , Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Timidilato Sintase/genética , Regiões 5' não Traduzidas/genética , Idoso , Feminino , Frequência do Gene/genética , Genótipo , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Repetições Minissatélites/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética
14.
Drugs Aging ; 25(6): 531-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18540691

RESUMO

BACKGROUND: Increasing evidence suggests that common gene polymorphisms may influence the toxicity of various cytotoxic agents used in the treatment of cancer. OBJECTIVE: To evaluate the predictive value of acute toxicity of methylenetetrahydrofolate reductase 677T polymorphism, glutathione S-transferase P1 (GSTP1) substitution of isoleucine with valine at codon 105 (Ile105Val) polymorphism and the tandem repeat polymorphism in the thymidylate synthase gene promoter in elderly patients with rectal cancer receiving preoperative chemoradiotherapy (CRT). METHOD: From 1994 to 2002, 166 Caucasian patients underwent surgery following CRT for mid-low rectal cancer at a single institution, 42 (male-to-female ratio, 25 : 17) of whom were aged > or =65 years (median age 70 years, range 65-79). The pre-treatment clinical stage was tumour (T) stage 3-4 in 38 patients and node (N)-positive in 29 patients. Patients received external-beam radiotherapy with conventional fractionation and fluorouracil-based chemotherapy. Blood samples were used to extract and amplify DNA. Gene polymorphisms were determined by polymerase chain reaction and restriction enzyme digestion. Acute toxicity to preoperative therapy was reported according to the National Cancer Institute Common Toxicity Criteria, version 2. Univariate and multivariate analyses were performed using one-way analysis of variance and linear regression, respectively. RESULTS: Haematological toxicity (grade 1-2) was observed in 15 of 40 patients for whom toxicity data were available and gastrointestinal toxicity (grade 1-4) in 24 of these same 40 patients. At univariate analysis, female sex (p = 0.036) and GSTP1 Ile105Val (p = 0.0376) were associated with haematological toxicity. At multivariate analysis, GSTP1 Ile105Val polymorphism (p = 0.041) was the only factor found to be associated with haematological toxicity. Patients carrying the Val/Val genotype in the GSTP1 gene had a lower risk of haematological toxicity (odds ratio = 0.322, 95% CI 0.101, 0.957) than patients with the Ile/Ile genotype. CONCLUSION: GSTP1 Ile105Val polymorphism is a promising marker of potential haematological toxicity in elderly patients with rectal cancer receiving preoperative CRT.


Assuntos
Adenocarcinoma/terapia , Glutationa S-Transferase pi/genética , Polimorfismo Genético , Neoplasias Retais/terapia , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/uso terapêutico , Quimioterapia Adjuvante/efeitos adversos , Feminino , Fluoruracila/efeitos adversos , Fluoruracila/uso terapêutico , Doenças Hematológicas/etiologia , Doenças Hematológicas/genética , Humanos , Masculino , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Análise Multivariada , Reação em Cadeia da Polimerase , Regiões Promotoras Genéticas , Radioterapia Adjuvante/efeitos adversos , Mapeamento por Restrição , Fatores Sexuais , Timidilato Sintase/genética
15.
J Leukoc Biol ; 81(6): 1512-22, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17339608

RESUMO

Cannabidiol (CBD), a prominent psychoinactive component of cannabis with negligible affinity for known cannabinoid receptors, exerts numerous pharmacological actions, including anti-inflammatory and immunosuppressive effects, the underlying mechanisms of which remain unclear. In the current study, we questioned whether CBD modulates activation of mast cells, key players in inflammation. By using the rat basophilic leukemia mast cell line (RBL-2H3), we demonstrate that CBD (3-10 muM) augments beta-hexosaminidase release, a marker of cell activation, from antigen-stimulated and unstimulated cells via a mechanism, which is not mediated by G(i)/G(o) protein-coupled receptors but rather is associated with a robust rise in intracellular calcium ([Ca(2+)](i)) levels sensitive to clotrimazole and nitrendipine (10-30 muM). This action, although mimicked by Delta(9)-tetrahydrocannabinol (THC), is opposite to that inhibitory, exerted by the synthetic cannabinoids WIN 55,212-2 and CP 55,940. Moreover, the vanilloid capsaicin, a full agonist of transient receptor potential channel VR1, did not affect [Ca(2+)](i)levels in the RBL-2H3 cells, thus excluding the involvement of this receptor in the CBD-mediated effects. Together, these results support existence of yet-to-be identified sites of interaction, i.e., receptors and/or ion channels associated with Ca(2+) influx of natural cannabinoids such as CBD and THC, the identification of which has the potential to provide for novel strategies and agents of therapeutic interest.


Assuntos
Cálcio/metabolismo , Canabidiol/farmacologia , Canabinoides/farmacologia , Degranulação Celular/fisiologia , Mastócitos/fisiologia , beta-N-Acetil-Hexosaminidases/metabolismo , Animais , Benzoxazinas/farmacologia , Capsaicina/farmacologia , Degranulação Celular/efeitos dos fármacos , Linhagem Celular , Cicloexanóis/farmacologia , Dronabinol/farmacologia , Líquido Intracelular/metabolismo , Mastócitos/efeitos dos fármacos , Mastócitos/imunologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Ratos , Canais de Cátion TRPV/agonistas
16.
Neurosci Lett ; 418(1): 9-12, 2007 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-17382472

RESUMO

Recent epidemiological studies raise the possibility that individuals with occupational exposure to low frequency (50-60 Hz) electromagnetic fields (LF-EMF), are at increased risk of Alzheimer's disease (AD). However, the mechanisms through which LF-EMF may affect AD pathology are unknown. We here tested the hypothesis that the exposure to LF-EMF may affect amyloidogenic processes. We examined the effect of exposure to 3.1 mT 50 Hz LF-EMF on Abeta secretion in H4 neuroglioma cells stably overexpressing human mutant amyloid precursor protein. We found that overnight exposure to LF-EMF induces a significant increase of amyloid-beta peptide (Abeta) secretion, including the isoform Abeta 1-42, without affecting cell survival. These findings show for the first time that exposure to LF-EMF stimulates Abeta secretion in vitro, thus alluding to a potential link between LF-EMF exposure and APP processing in the brain.


Assuntos
Doença de Alzheimer/etiologia , Peptídeos beta-Amiloides/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos da radiação , Glioma/patologia , Humanos , Exposição Ocupacional/efeitos adversos , Radiação
17.
Pharmacol Res ; 55(4): 318-28, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17292621

RESUMO

Long-term use of non-steroidal anti-inflammatory drugs (NSAIDs) may delay or prevent the onset of Alzheimer's disease (AD). A subset of NSAIDs, including flurbiprofen, has been shown to selectively inhibit the production of beta-amyloid(1-42) (Abeta42), independently from their cyclooxygenase (COX) inhibiting activity. We evaluated the in vitro and in vivo profiles of CHF5022 and CHF5074, two flurbiprofen analogues. The in vitro Abeta inhibiting activity was evaluated in a human neuroglioma cell line (H4) carrying the double Swedish mutation (K595N/M596L) of the human amyloid precursor protein (APPsw). The in vitro anti-COX activity was evaluated using human recombinant enzymes isolated from transfected Sf-9 cells. The in vivo pharmacokinetic and pharmacodynamic profiles of the two compounds were evaluated in young APPsw transgenic mice (Tg2576) after oral gavage (100 or 300mgkg(-1) day(-1) for 4-5 days) and after medicated diet (375ppm for 4 weeks). R-Flurbiprofen was used as comparator. In vitro, CHF5022 and CHF5074 were found to be 3- and 7-fold more potent than R-flurbiprofen in inhibiting Abeta42 secretion (IC(50)s of 92, 40 and 268microM, respectively). Differently from R-flurbiprofen, CHF5022 and CHF5074 did not affect COX-1 (at 100microM) and COX-2 (at 300microM) activity. Similarly to R-flurbiprofen, no significant alteration in the expression profile of a subset of Notch intracellular domain-responsive genes was observed with either CHF5022 or CHF5074. In Tg2576 mice, CHF5022 was well tolerated when administered by oral gavage (100mgkg(-1) day(-1) for 5 days) or by medicated diet (56mg kg(-1) day(-1) for 4 weeks). R-Flurbiprofen was poorly tolerated in the diet (32mgkg(-1) day(-1)) with 55% of the animals dying during the first week of treatment. After 4-5 days of oral gavage, CHF5022 and CHF5074 plasma and brain levels at 3h were found to increase with the dose, leading to brain concentrations of about 10% and 5% of the corresponding plasma concentrations, respectively. In animals fed for 4 weeks with compound-supplemented diet, mean plasma (580microM) and brain (20microM) Cyrillic) concentrations of CHF5022 were 8 and 15 times higher than those of R-flurbiprofen. Plasma Abeta42 concentration was dose-dependently decreased by CHF5022 and CHF5074. Brain Abeta levels (formic acid-extractable) were not significantly affected by either compound, although Abeta42 levels tended to inversely correlate (P=0.105) with CHF5022 concentration in the brain. CHF5022 and CHF5074 thus appear to have a promising in vitro and in vivo profile. This warrants further evaluation of their long-term effects on Abeta brain pathology.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Anti-Inflamatórios não Esteroides/farmacologia , Encéfalo/efeitos dos fármacos , Ciclopropanos/farmacologia , Flurbiprofeno/análogos & derivados , Flurbiprofeno/farmacologia , Nootrópicos/farmacologia , Fragmentos de Peptídeos/metabolismo , Administração Oral , Precursor de Proteína beta-Amiloide/genética , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclo-Oxigenase 1/efeitos dos fármacos , Ciclo-Oxigenase 1/genética , Ciclo-Oxigenase 1/metabolismo , Ciclo-Oxigenase 2/efeitos dos fármacos , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase/farmacologia , Ciclopropanos/administração & dosagem , Ciclopropanos/farmacocinética , Relação Dose-Resposta a Droga , Regulação para Baixo , Flurbiprofeno/administração & dosagem , Flurbiprofeno/farmacocinética , Expressão Gênica/efeitos dos fármacos , Humanos , Insetos/citologia , Proteínas de Membrana/efeitos dos fármacos , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Mutação , Nootrópicos/administração & dosagem , Nootrópicos/farmacocinética , Fatores de Tempo , Transfecção
18.
Ann Surg Oncol ; 14(3): 1058-64, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17106627

RESUMO

BACKGROUND: The identification of gastric tumors associated with a higher risk of lymph node metastasis could help surgeons select patients who may benefit from extended lymph node dissection. The aim of this study was to screen the genome in the search of primary gastric cancer gene expression profiles that might predict lymph node status. METHODS: The gene expression profile was evaluated in frozen tumor samples obtained from 32 patients with primary gastric adenocarcinomas. The array consisted of a duplicated spot panel of 5,541 human genes. To classify node-positive (N+) and node-negative (N-) cases, a logistic regression model was fitted optimizing the Akaike Information Criteria after a stepwise gene selection. The accuracy was evaluated by means of leave-one-out cross validation. RESULTS: All patients underwent radical gastrectomy and extended lymphadenectomy. Of all the cases, 21 were N+ and 11 demonstrated no lymph node involvement (N-). After quality filtering, the analysis of variance selected a set of 136 genes potentially correlated with nodal involvement (P value <.05). Of these 136 genes, 5 were differentially expressed (adjusted P value <.05). After a stepwise gene selection, only three genes (Bik, aurora kinase B, eIF5A2) were retained in the logistic model, which could correctly predict lymph node status in 30 of 32 cases. CONCLUSIONS: If our findings were confirmed, the identified gene pattern might be used to tailor the extent of lymph node dissection on a single patient basis.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Testes Genéticos/estatística & dados numéricos , Linfonodos/patologia , Neoplasias Gástricas/diagnóstico , Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Linfática , Estadiamento de Neoplasias , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo
19.
Pharmacogenet Genomics ; 16(11): 817-24, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17047490

RESUMO

OBJECTIVE: The objective of the present study was to evaluate whether germline methylenetetrahydrofolate reductase (MTHFR) C677T and A1298C polymorphisms as well as polymorphisms in the thymidylate synthase gene promoter, namely the variable number tandem repeat polymorphism (TS VNTR) and the intrarepeat G to C single nucleotide polymorphism (TS SNP), are predictive markers of tumor regression in rectal cancer patients following preoperative chemoradiotherapy. BASIC METHODS: Blood samples from 125 patients with primary adenocarcinoma of the mid-low rectum who received 5-fluorouracil-based chemotherapy and external beam radiotherapy (median dose 48.4 Gy), 125 patients (women n=45, men n=80; median age 60 years, range 31-79 years) were genotyped. Response to preoperative treatment was evaluated employing the Tumor Regression Grade criteria. On the basis of the pathologic response, patients were classified as responders (TRG 1-2, n=48) and non-responders (TRG 3-5, n=74). Three patients were excluded because of insufficient data. MAIN RESULTS: Among the polymorphic variants examined, the MTHFR 677T-1298A haplotype was, upon univariate analysis, the only variable found associated with tumor regression (P=0.004). Moreover, at multivariate analysis, the MTHFR 677T-1298A haplotype was an independent predictor of tumor regression. Patients not carrying the MTHFR 677T-1298A haplotype (odds ratio 0.29, 95% confidence interval 0.13-0.64, P=0.002) displayed a higher response rate than patients with the MTHFR 677T-1298A haplotype. CONCLUSIONS: Unlike TS VNTR and SNP polymorphisms, MTHFR 677T-1298A haplotype in genomic DNA has the potential to be a predictive marker of tumor response in rectal cancer patients submitted to preoperative chemoradiotherapy.


Assuntos
Adenocarcinoma/diagnóstico , Haplótipos , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Neoplasias Retais/diagnóstico , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/patologia , Adenocarcinoma/radioterapia , Adenocarcinoma/cirurgia , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Quimioterapia Adjuvante , Terapia Combinada , Feminino , Fluoruracila/uso terapêutico , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Polimorfismo Genético , Prognóstico , Doses de Radiação , Radioterapia Adjuvante , Neoplasias Retais/tratamento farmacológico , Neoplasias Retais/patologia , Neoplasias Retais/radioterapia , Neoplasias Retais/cirurgia , Indução de Remissão
20.
Cancer ; 106(5): 1007-16, 2006 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-16456808

RESUMO

BACKGROUND: In the current Phase II study, the authors evaluated the association between genomic polymorphic variants in uridine diphosphate glucuronosyl transferase (UGT1A1), methylenetetrahydrofolate reductase (MTHFR), and thymidylate synthase (TS) genes, and the incidence of the adverse effects of irinotecan and raltitrexed in previously heavily treated patients with metastatic colorectal carcinoma. METHODS: Fifty-six patients received irinotecan (at a dose of 80 mg/m(2) on Days 1, 8, 15, and 22 every 5 wks), combined with raltitrexed (at a dose of 3 mg/m(2) every 3 wks). Genotyping for the MTHFR C677T polymorphism, the TATA box region in the UGT1A1 promoter, and tandem repeats in the TS promoter was performed on genomic DNA extracted from blood. Nineteen variables related to patient, disease, and treatment characteristics, together with genotypes, were analyzed using a binary logistic regression model with stepwise selection to evaluate their correlation with adverse reactions. RESULTS: Toxicities (determined according to the National Cancer Institute Common Toxicity Criteria) were evaluated in 169 cycles. Grade 3/4 neutropenia was reported to occur in 2% of cycles, Grade 2-4 nausea was reported to occur in 19% of cycles, Grade 2-4 emesis was reported to occur in 9% of cycles, Grade 2-4 diarrhea was reported to occur in 20% of cycles, Grade 2/3 fatigue was reported to occur in 11% of cycles, and Grade 3/4 hepatic toxicity was reported to occur in 7% of cycles. Homozygosis for six TA repeats in the promoter region of the UGT1A1 gene was found to be the main predictive factor for diarrhea (P < 0.00005), emesis (P = 0.0001), and fatigue (P = 0.007). Homozygosis for two tandem repeats in the TS promoter was found to be predictive of a reduced incidence of fatigue (P = 0.044). MTHFR C677T polymorphism was not found to be associated with any adverse reaction. CONCLUSIONS: In the current study, UGT1A1 promoter polymorphism was found to be predictive of the risk of diarrhea, emesis, and fatigue caused by chemotherapy with irinotecan and raltitrexed. Screening for UGT1A1 promoter polymorphism may be clinically useful for identifying patients at a higher risk of developing a severe or potentially life-threatening toxicity after irinotecan-based chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma/tratamento farmacológico , Carcinoma/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Diarreia/induzido quimicamente , Fadiga/induzido quimicamente , Glucuronosiltransferase/genética , Vômito/induzido quimicamente , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Camptotecina/administração & dosagem , Camptotecina/efeitos adversos , Camptotecina/análogos & derivados , Carbono-Nitrogênio Ligases/genética , Carbono-Nitrogênio Ligases/metabolismo , Feminino , Genótipo , Glucuronosiltransferase/metabolismo , Humanos , Infusões Intravenosas , Irinotecano , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Polimorfismo Genético , Valor Preditivo dos Testes , Regiões Promotoras Genéticas , Quinazolinas/efeitos adversos , Tiofenos/efeitos adversos , Timidilato Sintase/genética , Timidilato Sintase/metabolismo
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