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1.
Sci Rep ; 10(1): 11762, 2020 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-32678138

RESUMO

Triple-negative breast cancer (TNBC) is an aggressive breast cancer subtype associated with a high rate of recurrence and poor prognosis. Recently we identified a hypermethylation in the long noncoding RNA 299 (LINC00299) gene in blood-derived DNA from TNBC patients compared with healthy controls implying that LINC00299 hypermethylation may serve as a circulating biomarker for TNBC. In the present study, we investigated whether LINC00299 methylation is associated with TNBC in a prospective nested breast cancer case-control study within the Generations Study. Methylation at cg06588802 in LINC00299 was measured in 154 TNBC cases and 159 breast cancer-free matched controls using MethyLight droplet digital PCR. To assess the association between methylation level and TNBC risk, logistic regression was used to calculate odd ratios and 95% confidence intervals, adjusted for smoking status. We found no evidence for association between methylation levels and TNBC overall (P = 0.062). Subgroup analysis according to age at diagnosis and age at blood draw revealed increased methylation levels in TNBC cases compared with controls in the young age groups [age 26-52 (P = 0.0025) and age 22-46 (P = 0.001), respectively]. Our results suggest a potential association of LINC00299 hypermethylation with TNBC in young women.

2.
Mol Oncol ; 14(6): 1252-1267, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32243066

RESUMO

Aberrant DNA methylation is often involved in carcinogenesis. Our initial goal was to identify DNA methylation biomarkers associated with pancreatic cancer. A genomewide methylation study was performed on DNA from pancreatic ductal adenocarcinoma (PDAC) and endocrine pancreas tumors. Validation of DNA methylation patterns and concomitant alterations in expression of gene candidates was performed on patient samples and pancreatic cancer cell lines. Furthermore, validation was done on independent data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Finally, droplet digital PCR was employed to detect DNA methylation marks in cell-free (cf) DNA isolated from plasma samples of PDAC patients and cancer-free blood donors. Hypermethylation of the SST gene (encoding somatostatin) and concomitant downregulation of its expression were discovered in PDAC and endocrine tumor tissues while not being present in chronic pancreatitis (inflamed) tissues and normal pancreas. Fittingly, treatment with a somatostatin agonist (octreotide) reduced cell proliferation and migration of pancreatic cancer cells. Diagnostic performance of SST methylation in a receiver operating characteristic curve analysis was 100% and 89% for tissue and plasma samples, respectively. A large body of TCGA and GEO data confirmed SST hypermethylation and downregulation in PDAC and showed a similar effect in a broad spectrum of other tumor entities. SST promoter methylation represents a sensitive and promising molecular, pan-cancer biomarker detectable in tumor tissue, and liquid biopsy samples.

3.
Breast Cancer Res Treat ; 181(2): 423-434, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279280

RESUMO

BACKGROUND: Three tools are currently available to predict the risk of contralateral breast cancer (CBC). We aimed to compare the performance of the Manchester formula, CBCrisk, and PredictCBC in patients with invasive breast cancer (BC). METHODS: We analyzed data of 132,756 patients (4682 CBC) from 20 international studies with a median follow-up of 8.8 years. Prediction performance included discrimination, quantified as a time-dependent Area-Under-the-Curve (AUC) at 5 and 10 years after diagnosis of primary BC, and calibration, quantified as the expected-observed (E/O) ratio at 5 and 10 years and the calibration slope. RESULTS: The AUC at 10 years was: 0.58 (95% confidence intervals [CI] 0.57-0.59) for CBCrisk; 0.60 (95% CI 0.59-0.61) for the Manchester formula; 0.63 (95% CI 0.59-0.66) and 0.59 (95% CI 0.56-0.62) for PredictCBC-1A (for settings where BRCA1/2 mutation status is available) and PredictCBC-1B (for the general population), respectively. The E/O at 10 years: 0.82 (95% CI 0.51-1.32) for CBCrisk; 1.53 (95% CI 0.63-3.73) for the Manchester formula; 1.28 (95% CI 0.63-2.58) for PredictCBC-1A and 1.35 (95% CI 0.65-2.77) for PredictCBC-1B. The calibration slope was 1.26 (95% CI 1.01-1.50) for CBCrisk; 0.90 (95% CI 0.79-1.02) for PredictCBC-1A; 0.81 (95% CI 0.63-0.99) for PredictCBC-1B, and 0.39 (95% CI 0.34-0.43) for the Manchester formula. CONCLUSIONS: Current CBC risk prediction tools provide only moderate discrimination and the Manchester formula was poorly calibrated. Better predictors and re-calibration are needed to improve CBC prediction and to identify low- and high-CBC risk patients for clinical decision-making.


Assuntos
Neoplasias da Mama/patologia , Tomada de Decisão Clínica , Segunda Neoplasia Primária/patologia , Medição de Risco/métodos , Adulto , Neoplasias da Mama/metabolismo , Neoplasias da Mama/cirurgia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Agências Internacionais , Mastectomia , Segunda Neoplasia Primária/metabolismo , Segunda Neoplasia Primária/cirurgia , Prognóstico , Receptor ErbB-2/metabolismo , Receptores Estrogênicos/metabolismo , Fatores de Risco
4.
Breast Cancer Res ; 21(1): 144, 2019 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-31847907

RESUMO

BACKGROUND: Breast cancer survivors are at risk for contralateral breast cancer (CBC), with the consequent burden of further treatment and potentially less favorable prognosis. We aimed to develop and validate a CBC risk prediction model and evaluate its applicability for clinical decision-making. METHODS: We included data of 132,756 invasive non-metastatic breast cancer patients from 20 studies with 4682 CBC events and a median follow-up of 8.8 years. We developed a multivariable Fine and Gray prediction model (PredictCBC-1A) including patient, primary tumor, and treatment characteristics and BRCA1/2 germline mutation status, accounting for the competing risks of death and distant metastasis. We also developed a model without BRCA1/2 mutation status (PredictCBC-1B) since this information was available for only 6% of patients and is routinely unavailable in the general breast cancer population. Prediction performance was evaluated using calibration and discrimination, calculated by a time-dependent area under the curve (AUC) at 5 and 10 years after diagnosis of primary breast cancer, and an internal-external cross-validation procedure. Decision curve analysis was performed to evaluate the net benefit of the model to quantify clinical utility. RESULTS: In the multivariable model, BRCA1/2 germline mutation status, family history, and systemic adjuvant treatment showed the strongest associations with CBC risk. The AUC of PredictCBC-1A was 0.63 (95% prediction interval (PI) at 5 years, 0.52-0.74; at 10 years, 0.53-0.72). Calibration-in-the-large was -0.13 (95% PI: -1.62-1.37), and the calibration slope was 0.90 (95% PI: 0.73-1.08). The AUC of Predict-1B at 10 years was 0.59 (95% PI: 0.52-0.66); calibration was slightly lower. Decision curve analysis for preventive contralateral mastectomy showed potential clinical utility of PredictCBC-1A between thresholds of 4-10% 10-year CBC risk for BRCA1/2 mutation carriers and non-carriers. CONCLUSIONS: We developed a reasonably calibrated model to predict the risk of CBC in women of European-descent; however, prediction accuracy was moderate. Our model shows potential for improved risk counseling, but decision-making regarding contralateral preventive mastectomy, especially in the general breast cancer population where limited information of the mutation status in BRCA1/2 is available, remains challenging.


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/etiologia , Segunda Neoplasia Primária/epidemiologia , Segunda Neoplasia Primária/etiologia , Área Sob a Curva , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Tomada de Decisão Clínica , Gerenciamento Clínico , Suscetibilidade a Doenças , Feminino , Mutação em Linhagem Germinativa , Humanos , Segunda Neoplasia Primária/patologia , Segunda Neoplasia Primária/prevenção & controle , Países Baixos/epidemiologia , Prognóstico , Modelos de Riscos Proporcionais , Medição de Risco , Fatores de Risco
5.
J Cell Physiol ; 2019 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-30677130

RESUMO

Aberrations of DNA methylation are early events in the development of tumors. In this study, we investigated the DNA methylation status of growth hormone secretagogue receptor (GHSR), a promising pan-cancer biomarker, in gastric cancer (GC). Initially, data sets from DNA methylation and gene expression studies available at Gene Expression Omnibus (GEO) were analyzed. Confirmation was done on primary tumor specimens and adjacent normal stomach tissue samples. Both analyses showed significant hypermethylation of GHSR. For further validation, The Cancer Genome Atlas data on stomach cancer was used. A receiver operating characteristic curve analysis yielded an area under the curve value of 0.85, corroborating its usefulness as a diagnostic marker. A genome-wide comethylation analysis revealed several correlated genes. CREB1 was found to act as an upstream regulator of this gene network. Furthermore, GHSR methylation was found to be a biomarker in several other tumor entities, namely cancers of the bladder, endometrium, esophagus, head and neck, liver, thyroid, kidney, and ovary. Our findings along with previous reports on other types of cancer suggest a high potential of GHSR gene methylation as a pan-cancer biomarker, which could be considered for liquid biopsy applications.

6.
Epigenomics ; 11(1): 81-93, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30208740

RESUMO

AIM: To identify DNA methylation biomarkers in peripheral blood samples from triple-negative breast cancer (TNBC) patients. MATERIALS & METHODS: We conducted an epigenome-wide association study (EWAS): the most promising markers were identified in 233 TNBC case-control pairs (discovery set) and subsequently validated in an independent validation set (57 TNBC patients and 124 controls). RESULTS: cg06588802 (LINC00299/ID2) showed a higher methylation in TNBC patients compared with controls (discovery set: 3% increase, p-value = 0.0009; validation set: 2% increase, p-value = 0.01). Consistent results at four neighboring methylation probes and the strong negative correlation (rho = -0.93) with LINC00299 expression add plausibility to this result. CONCLUSION: Hypermethylation of LINC00299 in peripheral blood may constitute a useful circulating biomarker for TNBC.


Assuntos
Biomarcadores Tumorais , Metilação de DNA , RNA Longo não Codificante/genética , Neoplasias de Mama Triplo Negativas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Neoplasias de Mama Triplo Negativas/patologia , Carga Tumoral , Adulto Jovem
7.
Int J Mol Sci ; 19(12)2018 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-30518158

RESUMO

Gastric cancer (GC) is the fifth most common cancer and the third most frequent cause of cancer deaths worldwide. The high death rate associated with GC, and lack of appropriate biomarkers for diagnosis, prognosis, and treatment emphasize the need for identification of novel molecules. Given the emerging roles for long non-coding RNAs (lncRNAs) in cancer development, we studied novel lncRNA candidates involved in gastric carcinogenesis. LncRNA candidate discovery was performed using analyses of available datasets and literature. Validation was done using an internal sample set of GC/normal tissues, and external independent datasets. Network analysis and functional annotation of co-expressed protein coding genes were performed using the weighted gene correlation network analysis (WGCNA) and ingenuity pathway analysis. Two novel lncRNAs, PCAT18 and LINC01133, associated with GC development were identified by analysis of the discovery Gene Expression Omnibus (GEO) datasets. The down-regulation of these genes in GC tissues was successfully validated internally and externally. The results showed a tissue-specific down-regulation of PCAT18 and LINC01133 in gastrointestinal tissues. WGCNA and ingenuity pathway analyses revealed that the genes co-expressed with the two lncRNAs were mostly involved in metabolic pathways and networks of gastrointestinal disease and function. Our findings of a tissue-specific down-regulation of PCAT18 and LINC01133 in gastric and other gastrointestinal cancers imply that these lncRNAs may have a tumor suppressive function in the development of these tumor entities. The two lncRNA biomarkers may contribute to a better understanding of the complex mechanisms of gastric carcinogenesis.


Assuntos
Carcinogênese/genética , Regulação para Baixo/genética , Regulação Neoplásica da Expressão Gênica , Especificidade de Órgãos/genética , RNA Longo não Codificante/genética , Neoplasias Gástricas/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Carcinogênese/patologia , Redes Reguladoras de Genes , Humanos , Pessoa de Meia-Idade , Anotação de Sequência Molecular , RNA Longo não Codificante/metabolismo , Neoplasias Gástricas/patologia
8.
Behav Brain Res ; 329: 104-110, 2017 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-28442361

RESUMO

Spinal cord injury (SCI) often leads to constant neurological deficits and long-term unalterable disability. Apoptosis plays an important role in the initiation of the secondary injury cascades leading to progressive tissue damage and severely functional deficits after SCI. Although the primary mechanical destructive events cannot be reversed, a therapeutic intervention could be carried out in order to moderate the secondary injury damage several hours to weeks after injury. Astaxanthin (AST) is a strong antioxidant and anti-inflammatory agents with the potential to render anti-apoptotic and neuroprotective effects. In the current study, we examined the therapeutic potential of AST on adult rats after severe SCI contusion. Results of BBB scores showed that AST improved motor function after SCI compared to control groups. Western blot analysis showed reduced expression of Bax and Cleaved-caspase-3 proteins and increased expression of the Bcl-2 protein in response to AST treatment (p<0.05). The histology results also showed that AST considerably preserved myelinated white matter and the number of motor neurons. This study is the first to report that AST reduces neuronal apoptosis, diminishes pathological tissue damage and improves functional recovery after SCI. The observed prominent neuroprotective effects, introduces AST as a promising therapy for SCI.


Assuntos
Fármacos Neuroprotetores/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Locomoção/efeitos dos fármacos , Masculino , Neurônios/efeitos dos fármacos , Neurônios/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Wistar , Medula Espinal/patologia , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologia , Fatores de Tempo , Xantofilas/uso terapêutico , Proteína X Associada a bcl-2/metabolismo
9.
Oncol Lett ; 12(1): 285-290, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27347139

RESUMO

Aberrant DNA methylation has been investigated in carcinogenesis and as biomarker for the early detection of colorectal cancer (CRC). The present study aimed to define the methylation status in the regulatory elements of two proapoptotic genes, Fas cell surface death receptor (FAS) and BCL2-associated X protein (BAX). DNA methylation analysis was performed in tumor and adjacent normal tissue using HpaII/MspI restriction digestion and methylation-specific polymerase chain reaction (PCR). The results observed downregulation of the FAS and BAX genes in the CRC tissues compared with the adjacent normal samples. Furthermore, demethylation using 5-aza-2'-deoxycytidine treatment followed by reverse-transcription quantitative PCR were performed on the HT-29 cell line to measure BAX and FAS mRNA expression following demethylation. The 5-aza-2'-deoxycytidine treatment resulted in significant FAS gene upregulation in the HT-29 cell line, but no significant difference in BAX expression. Furthermore, analysis of CpG islands in the FAS gene promoter revealed that the FAS promoter was significantly hypermethylated in 53.3% of tumor tissues compared with adjacent normal samples. Taken together, the results indicate that decreased expression of the FAS gene due to hypermethylation of its promoter may lead to apoptotic resistance, and acts as an important step during colorectal carcinogenesis.

10.
Pathol Res Pract ; 211(6): 444-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25795228

RESUMO

AIM: Human papillomaviruses (HPV) have frequently been detected in colorectal cancer tumor samples, and may play a role in the pathogenesis of colorectal cancer. This study was designed to investigate the presence of DNA and RNA for the high-risk HPV genotypes 16 and 18 in samples of colorectal cancer tumors and adjacent normal tissues. We also investigated the expression of proapoptotic genes in HPV-positive colorectal tumors compared to normal tissue samples. METHODS: Samples of tumoral and adjacent normal tissues were fresh-frozen, and HPV DNA was identified by nested and semiquantitative PCR. Real time PCR was used to quantitatively compare the expression of HPV-18 E6 and nine proapoptotic genes in HPV-positive tumors and samples of adjacent normal tissue. RESULTS: HPV-16 DNA was found in 10.5% of the tumor samples, and HPV-18 DNA was found in 23.6% of the samples. Real time PCR results showed lower expression of the E6 gene in HPV-positive tumors than in adjacent normal tissue. The expression of two proapoptotic genes, FAS and DR5, was significantly lower in tumor samples than in adjacent normal tissues. CONCLUSIONS: HPV infection, especially HPV-18, may play a role in colorectal cancer tumorigenesis by downregulating death receptor genes and interfering with the extrinsic pathway of apoptosis.


Assuntos
Neoplasias Colorretais/virologia , Papillomavirus Humano 16 , Papillomavirus Humano 18/genética , Infecções por Papillomavirus/virologia , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Receptor fas/metabolismo , Adenocarcinoma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , DNA Viral/genética , Regulação para Baixo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Oncotarget ; 6(6): 4418-27, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25557172

RESUMO

Identification of a single molecular trait that is determinant of common malignancies may serve as a powerful diagnostic supplement to cancer type-specific markers. Here, we report a DNA methylation mark that is characteristic of seven studied malignancies, namely cancers of lung, breast, prostate, pancreas, colorectum, glioblastoma and B cell chronic lymphocytic leukaemia (CLL) (n = 137). This mark was defined by substantial hypermethylation at the promoter and first exon of growth hormone secretagouge receptor (GHSR) through bisulfite pyrosequencing. The degree of aberrant methylation was capable of accurate discrimination between cancer and control samples. The highest sensitivity and specificity of cancer detection was achieved for cancers of pancreas, lung, breast and CLL yielding the area under the curve (AUC) values of 1.0000, 0.9952, 0.9800 and 0.9400, respectively. Narrowing to a single CpG site within the gene's promoter or four consecutive CpG units of the highest methylation levels within the first exon improved the detection power. GHSR hypermethylation was detected already at the early stage tumors. The accurate performance of this marker was further replicated in an independent set of pancreatic cancer and control samples (n = 78). These findings support the candidature of GHSR methylation as a highly accurate pan-cancer marker.


Assuntos
Biomarcadores Tumorais/genética , Metilação de DNA/genética , Epigênese Genética , Neoplasias/genética , Receptores de Grelina/genética , Adulto , Área Sob a Curva , Biomarcadores Tumorais/análise , Epigênese Genética/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Curva ROC , Receptores de Grelina/análise
12.
Iran J Reprod Med ; 12(3): 217-20, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24799883

RESUMO

BACKGROUND: Hypospadias is one of the most common congenital abnormalities in the male which is characterized by altered development of urethra, foreskin and ventral surface of the penis. Androgen receptor gene plays a critical role in the development of the male genital system by mediating the androgens effects. OBJECTIVE: In present study, we looked for new variations in androgen receptor promoter and screened its exon 1 for five single nucleotide polymorphisms (SNP) in healthy and hypospadias Iranian men. MATERIALS AND METHODS: In our study, at first DNA was extracted from patients (n=100) and controls (n=100) blood samples. Desired fragments of promoter and exon 1 were amplified using polymerase chain reaction. The promoter region was sequenced for the new variation and exone 1 screened for five SNPs (rs139767835, rs78686797, rs62636528, rs62636529, rs145326748) using restriction fragment length polymorphism technique. RESULTS: The results showed a new single nucleotide variation (C→T) at -480 of two patients' promoter region (2%). None of the mentioned SNPs were detected in patients and controls groups (0%). CONCLUSION: This finding indicates that new single nucleotide polymorphism in androgen receptor promoter may have role in etiology of hypospadias and development of this anomaly. This article extracted from Ph.D. thesis. (Nasim Borhani).

13.
Pathol Oncol Res ; 20(2): 301-7, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24122668

RESUMO

Carcinogenesis and resistance to chemotherapy could be as results of expression variations in apoptosis regulating genes. Changes in the expression of apoptosis interfering genes may contribute to colorectal carcinogenesis and resistance to 5-Flourouracil (5-FU) during treatment schedule period. The present study aimed to evaluate the expression of pro-apoptotic and anti-apoptotic genes in colorectal cancer tumor tissues, normal adjacent tissues, and tumor colorectal cancer cell line during acquiring resistance to 5-FU in HT-29 based on Bolus treatment protocol. The normal and tumor tissues were obtained from hospital after surgery and total RNA was extracted for expression analysis. The HT-29 colorectal cancer cell line was cultured and exposed with 5-FU in three stages based on Bolus protocol. The MTT assay and Real Time PCR were carried out to determine the sensitivity to the drug and expression of desired genes, respectively. The obtained data showed that Proapoptotic genes, BAX and BID, were down-regulated in resistant derivate cells compared to wild type HT-29 cells. On the other hand Antiapoptotic genes, CIAP1 and XIAP, showed upregulation in resistant cells compared to wild type ones. Furthermore, BAX and FAS genes showed down-regulation in tumor samples in comparison to normal adjacent tissues. In conclusion, the results of our study suggest that BAX down-regulation could contribute as an important factor during both colorectal carcinogenesis and cell resistance to 5-FU.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Regulação para Baixo/genética , Resistencia a Medicamentos Antineoplásicos/genética , Fluoruracila/uso terapêutico , Proteína X Associada a bcl-2/genética , Apoptose/efeitos dos fármacos , Apoptose/genética , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Regulação para Baixo/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Células HT29 , Humanos , Proteínas Inibidoras de Apoptose/genética , Masculino , Pessoa de Meia-Idade , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Receptor fas/genética
14.
Iran J Basic Med Sci ; 15(4): 937-44, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23493039

RESUMO

OBJECTIVE(S): Alzheimer's disease (AD) is a complex disease with multifactorial etiology. Inflammation has been proven to have an important role in the pathogenesis of AD. Both CCR2 and CCR5 genes expression increase in AD patients comparing to control subjects. CCR5 gene encodes a protein which is a member of the beta chemokine receptors family of integral membrane proteins. CCR5-Δ32 is a genetic variant of CCR5 and is characterized by the presence of a 32-bp deletion in the coding region of the gene, which leads to the expression of a nonfunctional receptor, and the CCR2-64I has a change of valine to isoleucine at codon 64, in the first transmembrane domain. It has been proved that both genes have important roles in different stages of inflammation. MATERIALS AND METHODS: The frequencies of CCR5∆32 and CCR2-64I variations were determined in 156 AD patients and 161 control subjects using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods, and the results were compared among AD and healthy controls. Results :Statistical analysis showed no significant difference in the distributions of CCR5∆32 and CCR2-64I between the AD patients and healthy controls (P> 0.05). Stratifying the samples by gender, genetic background and presence of ApoEε4 allele showed no significant effect on the distributions of CCR5∆32 and CCR2-64I (P> 0.05). CONCLUSION: Our study did not show an association between CCR5∆32 and CCR2-64I variations and AD in the Iranian population. Further confirmatory studies with bigger number of samples are recommended.

15.
Avicenna J Med Biotechnol ; 2(3): 153-7, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23408664

RESUMO

Alzheimer's disease (AD) is a genetically heterogeneous neurodegenerative disease and Late-Onset type (LOAD) is the most common form of dementia affecting people over 65 years old. CALHM1 (P86L) encodes a transmembrane glycoprotein that controls cytosolic Ca(2+) concentrations and Aß levels and P86L polymorphism in this gene is significantly associated with LOAD in independent case controls in a number of studies. This study was performed to determine whether this polymorphism contributes to the risk for LOAD in Iranian population. One hundred and forty one AD patients and 141 healthy controls were recruited in this study. After extraction of genomic DNA, the genotype and allele frequencies were determined in case and control subjects using PCR/RFLP method. The statistical analysis showed a significant difference in the heterozygote genotype frequency in case and control groups and polymorphic allele had a protective role between two groups. Also after stratifying the subjects by their APOE-ɛ4 status, no significant association was observed. Our study suggests that P86L polymorphism could be a protective factor for late-onset Alzheimer's disease (LOAD) in Iranian population. However, to confirm these results, further study with a bigger sample size may be required.

16.
Avicenna J Med Biotechnol ; 1(3): 193-7, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23408162

RESUMO

Late-onset Alzheimer's Disease (LOAD) is a neurodegenerative disorder and the most common form of dementia affecting people over 65 years old. Alzheimer's disease is a complex disease with multi-factorial etiology. Inflammation has been approved to have an important role in the pathogenesis of Alzheimer's disease (AD). TNF-α is a main pro-inflammatory cytokine that plays an essential role in initiation and regulation of inflammatory responses. Several studies have shown the probable association of polymorphism at TNF-α gene's promoter with AD pathogenesis. This study was performed to determine whether this polymorphism contributes to the risk for late-onset Alzheimer's disease (LOAD) in Iranian population. One hundred and forty AD patients and 158 healthy controls were recruited in the study. Following extraction of genomic DNA, using PCR/RFLP methods the genotype and allele frequencies were determined in case and control subjects. The statistical analysis showed no significant difference in the allele and genotype frequencies due to this polymorphism between the two groups. Also after stratifying the subjects by their APOE-ɛ4 status, no significant association was observed. Our results suggest that Tumor necrosis factor-alpha (TNF-α)-308 G/A is not a risk or protective factor for late-onset Alzheimer's disease in Iranian population. However, to confirm these results further study with a bigger sample size may be required.

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