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1.
Proc Natl Acad Sci U S A ; 120(31): e2216127120, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37487091

RESUMO

Retroviruses and their host have coevolved in a delicate balance between viral replication and survival of the infected cell. In this equilibrium, restriction factors expressed by infected cells control different steps of retroviral replication such as entry, uncoating, nuclear import, expression, or budding. Here, we describe a mechanism of restriction against human T cell leukemia virus type 1 (HTLV-1) by the helicase-like transcription factor (HLTF). We show that RNA and protein levels of HLTF are reduced in primary T cells of HTLV-1-infected subjects, suggesting a clinical relevance. We further demonstrate that the viral oncogene Tax represses HLTF transcription via the Enhancer of zeste homolog 2 methyltransferase of the Polycomb repressive complex 2. The Tax protein also directly interacts with HLTF and induces its proteasomal degradation. RNA interference and gene transduction in HTLV-1-infected T cells derived from patients indicate that HLTF is a restriction factor. Restoring the normal levels of HLTF expression induces the dispersal of the Golgi apparatus and overproduction of secretory granules. By synergizing with Tax-mediated NF-κB activation, physiologically relevant levels of HLTF intensify the autophagic flux. Increased vesicular trafficking leads to an enlargement of the lysosomes and the production of large vacuoles containing viral particles. HLTF induction in HTLV-1-infected cells significantly increases the percentage of defective virions. In conclusion, HLTF-mediated activation of the autophagic flux blunts the infectious replication cycle of HTLV-1, revealing an original mode of viral restriction.


Assuntos
Vírus Linfotrópico T Tipo 1 Humano , Leucemia de Células T , Humanos , Vírus Linfotrópico T Tipo 1 Humano/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Produtos do Gene tax/genética , Produtos do Gene tax/metabolismo , Linfócitos T/metabolismo , NF-kappa B/metabolismo , Proteínas de Ligação a DNA
3.
Clin Exp Med ; 18(2): 221-227, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29076004

RESUMO

In acute lymphoblastic leukemia (ALL), limited data are available on mTOR gene expression in clinical samples and its role in predicting response to induction chemotherapy. mRNA expression of mTOR gene was determined quantitatively by real-time PCR in 50 ALL patients (30 B-ALL and 20 T-ALL) and correlated with clinical outcome after induction chemotherapy. Expression level of mTOR was upregulated in more than 50% of cases of ALL. In T-ALL, high expression of mTOR was commonly seen, more in adults than children (82 vs. 55% cases), while in B-ALL it was same (~ 63% cases) in both adults and children. Mean fold change of mTOR expression was significantly higher in non-responders compared to responders of both adult B-ALL (7.4 vs. 2.7, p = 0.05) and T-ALL (13.9 vs. 2.4, p = 0.001). Similar results were seen in pediatric non-responders when compared to responders of both B-ALL (14.5 vs. 2.5, p = 0.006) and T-ALL (24.2 vs. 1.7, p = 0.002). Interestingly, we have observed that mTOR expression was two times higher in non-responders of children compared to adults in both B-ALL (14.5 vs. 7.4, p = 0.05) and T-ALL (24.2 vs. 13.9, p = 0.01). Multivariate analysis with other known prognostic factors revealed that mTOR expression independently predicts clinical response to induction chemotherapy in ALL. This study demonstrates that high mTOR expression is associated with poor clinical outcome in ALL and can serve as a potential target for novel therapeutic strategies.


Assuntos
Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Serina-Treonina Quinases TOR/genética , Regulação para Cima , Adulto , Criança , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Quimioterapia de Indução , Masculino , Prognóstico , Resultado do Tratamento
4.
Tumour Biol ; 36(4): 3061-73, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25514873

RESUMO

High incidence of nasopharyngeal carcinoma (NPC) has been reported from China, Southeast Asia and Northeast (NE) region of India. Populations at geographic regions having higher incidence of NPC display human leukocyte antigen (HLA) distribution patterns different from areas having low incidence. The current study has investigated the contribution of environmental risk factors and ethnic variation of microsatellite markers in HLA region for the high incidence of NPC in NE India. Genotyping of HLA region using 33 microsatellite markers by fragment length analysis was done in 220 study subjects (120 NPC patients and 100 healthy controls). Association analysis showed two adjacent microsatellite markers HL003 (allele 121) and D6S2704 (allele 218) in the HLA class I region having association with high risk of NPC while allele 127 of HL003 and allele 255 of D6S2678 conferred a protective effect. The environmental factors mainly use of firewood (odds ratio (OR) = 3.797385, confidence interval (CI) = 1.97-7.30, P < 0), living in mud house (OR = 3.46, CI = 1.19-10.08, P = 0.022) and consumption of alcohol (OR = 2.11, CI = 1.02-4.37, P = 0.043) were found as major risk factors for NPC. Higher-order interaction showed combination of smoked food consumption and firewood use for cooking in multifactor dimensionality reduction (MDR) analysis and interaction of non-firewood users, non-ventilated houses and residence in mud houses in classification and regression tree (CART) analysis as the significant risk factors for NPC. Expression of Epstein-Barr virus (EBV) RNA was found in 92% (23/25) of NPC cases suggesting its significant role in NPC aetiopathogenesis. This study identified association of NPC with a susceptibility locus in the HLA class I region which has complex interaction with viral DNA and environmental factors.


Assuntos
Estudos de Associação Genética , Antígenos HLA/genética , Repetições de Microssatélites/genética , Neoplasias Nasofaríngeas/genética , Adulto , Idoso , Alelos , Feminino , Predisposição Genética para Doença , Genótipo , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/patogenicidade , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/virologia , Fatores de Risco
5.
Indian J Med Res ; 139(5): 720-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25027082

RESUMO

BACKGROUND & OBJECTIVES: Genetic polymorphisms in glutathione-S-transferase genes ( GSTM1 and GSTT1 ) have been studied intensively for their potential role in lung cancer susceptibility. However, most of the studies on association between the polymorphisms and lung cancer do not distinguish between genotypes with one or two copies of the genes. The present study investigates the gene dosage effects of GSTT1 and GSTM1 copy number and their environmental interactions to examine the association of lung cancer risk with trimodular genotypes of the GSTs in a high-risk population from north-east India. METHODS: A total of 154 lung cancer cases and 154 age and sex matched controls from the high risk region of north-east India were analyzed by multiplex real-time PCR to determine the trimodal genotypes (+/+, +/- and -/-) in both the genes ( GSTM1 and GSTT1 ). RESULTS: No significant association and gene dosage effect of GSTM1 gene copy number with lung cancer risk ( P trend =0.13) were found. However, absence of GSTT1 conferred 68 per cent (OR=0.32;95%CI=0.15-0.71;P=0.005) reduced risk compared to the two copy number of the gene. t0 here was evidence of gene dosage effect of GSTT1 gene ( P trend =0.006). Tobacco smoking was a major environmental risk factor to lung cancer (OR=3.03;95%CI=1.73-5.31;P<0.001). However, its interaction with null genotype of GSTT1 conferred significant reduced risk to lung cancer (OR=0.30;95%CI=0.10-0.91;P=0.03). Further in only tobacco smokers, null genotype was associated with increased reduced risk [0.03(0.001-0.78)0.03; P trend =0.006]. No effect modification of GSTM1 was observed with lung cancer risk by environmental risk factors. INTERPRETATION & CONCLUSIONS: The results suggest that absence of GSTT1 null genotype may be associated with a reduced risk of lung cancer and the effect remains unchanged after interaction with smoking.


Assuntos
Variações do Número de Cópias de DNA , Glutationa Transferase/genética , Neoplasias Pulmonares/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Glutationa/metabolismo , Humanos , Índia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/genética
6.
Tumour Biol ; 35(6): 5885-94, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24604328

RESUMO

Polymorphisms in DNA repair and cell cycle genes contribute to increased breast cancer (BC) risk. Their association and interaction in relation to betel quid and tobacco chewing habits need exhaustive multi-analytical investigation to explain BC predisposition due to DNA damage. Polymorphism in TP53-72Arg>Pro, RAD51-135G>C, BRCA2, and CCND1-G870A were examined in 204 BC cases and 217 controls from Northeast Indian population. Multifaceted analytic approaches were used to explore relationships between polymorphisms, tobacco history, and BC susceptibility. Betel quid chewing was identified as the predominant risk factor. CCND-AA and dominant model showed protection towards BC in betel quid chewer (BQC) [(0.28 (0.10-0.77), 0.01 and 0.32 (0.12-0.81), 0.01)] and non-betel quid chewers (NBQC) [(0.26 (0.09-0.78), 0.01 and 0.37 (0.16-0.87), 0.02)]. TP53-Pro/Pro genotype showed protection towards BC in NBQC (0.29 (0.10-0.81), p=0.01) and (0.51 (0.32-0.80), p=0.003, respectively). RAD51-C allele was associated with BC risk (2.03 (1.26-3.30) 0.002) in BQC. Two BQC cases had BRCA2 8415G>T:K2729N mutation in Exon18. MDR analysis showed best four locus model with TBA 0.6765 (0.005) and CVC of 10/10 in NBQC. Interaction diagram concurred the interactions between TP53 and RAD51 (1.32 %) with independent effect (1.89 %) of CCND1in NBQC. In CART analysis, BQC with CCND1 GG genotype were at risk (OR=33.0; 95 % CI=6.08-179.07), p<0.001) followed by combination of BQC, CCND1, No-Smk, and Alc (OR=42.00; 95 % CI=5.11-345.11, p<0.001). Risk was also observed in BQC, CCND1, No-Smk, Non-Alc, and TP53 combination (OR=14.84; 95 % CI=3.13-70.34, p<0.001) and BQC, CCND1, No-Smk, Non-Alc, TP53 (OR=9.40; 95 % CI=1.99-44.34, p<0.001). NBQC group showed risk with combination of NBQC and TP53 (OR=5.54; 95 % CI=1.11-27.42, p=0.03). Genetic variants in DNA repair and cell cycle genes contribute to BC risk through gene-gene and gene-environmental interactions.


Assuntos
Neoplasias da Mama/genética , Ciclo Celular/genética , Reparo do DNA/genética , Predisposição Genética para Doença , Adulto , Idoso , Areca/efeitos adversos , Neoplasias da Mama/etiologia , Ciclina D1/genética , Entropia , Feminino , Genes BRCA2 , Genes p53 , Variação Genética , Humanos , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Rad51 Recombinase/genética , Risco
7.
Cancer Genet ; 207(1-2): 1-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24561215

RESUMO

The IL-1ß -511 C/T polymorphism is associated with increased IL-1 production and with increased risk of developing cancers. In this study, 251 patients (125 with gastric cancer [GC] and 126 with oral cancer [OC]) and 207 normal controls from northeast (NE) India were genotyped for the IL-1ß -511 C/T polymorphism by PCR-restriction fragment length polymorphism (RFLP) and sequencing. Analysis of results showed betel-quid chewing to be a major risk factor (OR = 2.01, 95% CI = 1.05-3.87; P = 0.035) for OC. Inheritance of the IL-1ß -511 CT or TT resulted in a 2.6- to 3.05-fold increase in the risk of developing OC relative to that of participants who possessed the reference genotype (OR = 2.57, 95% CI = 1.06-6.22; P = 0.036 and OR = 3.05, 95% CI = 1.22-7.63; P = 0.017), after adjusting for potential confounders. The dominant genetic model also confirmed the presence of the T allele as a significant risk factor for OC (OR = 2.72, 95% CI = 1.15-6.42; P = 0.02). In GC, interaction of the CT genotype with tobacco and betel-quid chewing habits conferred a significant 78% and 89% reduced risk of cancer, respectively. In conclusion, for the NE Indian population, the IL-1ß -511 CC and CT genotypes were significantly associated with increased risk of OC. However, the interaction of the CT genotype with risk habits may play a preventive role for GC but not for OC.


Assuntos
Interleucina-1beta/genética , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/genética , Adulto , Idoso , Consumo de Bebidas Alcoólicas , Alelos , Areca/efeitos adversos , Estudos de Casos e Controles , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/etiologia , Razão de Chances , Polimorfismo de Fragmento de Restrição , Fatores de Risco , Análise de Sequência de DNA , Fumar/efeitos adversos , Neoplasias Gástricas/etiologia , Nicotiana/efeitos adversos , Tabaco sem Fumaça/efeitos adversos
8.
Tumour Biol ; 35(1): 723-37, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23982874

RESUMO

Targeting breast cancer stem cells (BCSCs) offers a promising strategy for breast cancer treatment. We examined the plant alkaloid ellipticine for its efficacy to inhibit the expression of aldehyde dehydrogenase 1 class A1 (ALDH1A1)-positive BCSCs by in vitro and in silico methods. At 3 mM concentration, ellipticine decreased the expression of ALDH1A1-positive BCSCs by 62% (p = 0.073) in the MCF7 cell line and by 53% (p = 0.024) in the SUM159 cell line compared to vehicle-treated cultures. Ellipticine significantly reduced the formation of mammospheres, whereas paclitaxel enhanced mammosphere formation in both the treated cell lines. Interestingly, when treated with a combination of ellipticine and paclitaxel, the percentage of ALDH1A1-positive BCSCs dropped by several fold in vitro. A homology model of Homo sapiens ALDH1A1 was built using the crystal structure of NAD-bound sheep liver class I aldehyde dehydrogenase [PDB ID: 1BXS] as a template. Molecular simulation and docking studies revealed that the amino acids Asn-117 and Asn-121, Glu-249, Cys-302, and Gln-350, present in the active site of human ALDH1A1, played a vital role in interacting with the drug. The present study suggests that ellipticine reduces the proliferation and self-renewal ability of ALDH1A1-positive BCSCs and can be used in combination with a cytotoxic drug like paclitaxel for potential targeting of BCSCs.


Assuntos
Aldeído Desidrogenase/metabolismo , Antineoplásicos/farmacologia , Neoplasias da Mama/metabolismo , Elipticinas/farmacologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Aldeído Desidrogenase/química , Aldeído Desidrogenase/genética , Família Aldeído Desidrogenase 1 , Sequência de Aminoácidos , Antineoplásicos/química , Neoplasias da Mama/genética , Domínio Catalítico , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Elipticinas/química , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Dados de Sequência Molecular , Paclitaxel/farmacologia , Ligação Proteica , Conformação Proteica , Retinal Desidrogenase , Esferoides Celulares , Células Tumorais Cultivadas
9.
Dis Markers ; 35(5): 581-8, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24288427

RESUMO

BACKGROUND: Mutations in NPM1 and FLT3 genes represent the most frequent genetic alterations and important diagnostic and prognostic indicators in patients with acute myeloid leukemia (AML). OBJECTIVE: We investigated the prevalence and clinical characteristics of NPM1 and FLT3 mutations in 161 patients of de novo AML including adults and children. RESULTS: NPM1 mutation was found in 21% and FLT3 mutation in 25% of the AML patients. Thirteen (8%) samples were positive for both NPM1 and FLT3/ITD mutations. Adult patients had significantly higher frequency of NPM1 mutation than children (25.8% versus 8.8%; P = 0.02). Further, NPM1 mutation was found to be more frequent in patients above 45 years of age (P = 0.02). NPM1 mutation was significantly associated with higher platelet count (P = 0.05) and absence of hepatosplenomegaly (P = 0.01), while FLT3/ITD mutation was associated with higher white blood count (P = 0.01). Immunophenotypically, NPM1 mutation was associated with the lack of CD34 (P < 0.001) and HLD-DR expression (P < 0.001), while FLT3/ITD mutation was positively associated with the expression of CD7 (P = 0.04). No correlation was found between NPM1 mutation and fusion gene. Interestingly, FLT3/ITD mutation was found to be inversely associated with AML/ETO fusion gene (P = 0.04). CONCLUSIONS: The results suggest that distinct clinical and immunophenotypic characteristics of NPM1 and FLT3/ITD mutations present further insight into the molecular mechanism of leukemogenesis.


Assuntos
Leucemia Mieloide Aguda/genética , Mutação , Proteínas Nucleares/genética , Fenótipo , Tirosina Quinase 3 Semelhante a fms/genética , Adulto , Fatores Etários , Antígenos CD34/genética , Antígenos CD34/metabolismo , Antígenos CD7/genética , Antígenos CD7/metabolismo , Criança , Feminino , Frequência do Gene , Humanos , Leucemia Mieloide Aguda/diagnóstico , Leucemia Mieloide Aguda/imunologia , Masculino , Nucleofosmina , Contagem de Plaquetas
10.
Environ Mol Mutagen ; 53(8): 619-30, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22930568

RESUMO

Polymorphisms in xenobiotic metabolizing genes are associated with altered metabolism of carcinogens in acute leukemia (AL). This study applied two data mining approaches to explore potential interactions among P53 and xenobiotic metabolizing genes in 230 AL patients [131 acute myeloid leukemia (AML) and 99 acute lymphoblastic leukemia (ALL)] and 199 controls. Individually, none of the genotypes showed significant associations with AML risk. However, in ALL the CYP1A12A TC genotype was associated with increased risk (OR = 2.02; 95% CI = 1.14-3.58; P = 0.01), whereas the GSTM1 null genotype imparted reduced risk (OR = 0.55; 95% CI = 0.31-0.96; P = 0.03). In classification and regression tree analysis, combinations of GSTM1 present, CYP1A12C AA or GG, EPHX1 exon3 TC, and EPHX1 exon4 AA or GG genotype strongly enhanced the risk of AML (OR = 5.89; 95% CI = 1.40-26.62; P = 0.01). In ALL, combinations of CYP1A12A TT, P53 GG or CC and GSTP1 AG genotypes conferred the highest risk (OR = 4.19; 95% CI = 1.45-12.25; P = 0.004). In multifactor dimensionality reduction analysis, a four locus model (GSTP1, P53, EPHX1 exon3, and CYP1A12A) was the best predictor model for ALL risk. The association between this model and ALL risk remained true even at low prior probabilities of 0.01% (false positive report probability = 0.05). Interaction entropy interpretations of the best model of ALL revealed that two-way interactions were mostly synergistic. These results suggest that high order gene-gene interactions play an important role in AL risk.


Assuntos
Leucemia/genética , Polimorfismo Genético/genética , Proteína Supressora de Tumor p53/genética , Xenobióticos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Epóxido Hidrolases/genética , Feminino , Predisposição Genética para Doença/genética , Genótipo , Glutationa S-Transferase pi/genética , Glutationa Transferase/genética , Humanos , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adulto Jovem
11.
Exp Mol Pathol ; 92(1): 44-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22037714

RESUMO

Resistance to chemotherapy is a major impediment to the successful treatment of acute leukemia (AL). Expression of genes involved in drug resistance and apoptosis may be responsible for this. This study aimed to investigate the expression of drug resistance (MDR1, MRP1, LRP, BCRP, GSTP1, DHFR) and apoptotic genes (p53, BCL-2, Survivin) in adult acute leukemias and compare them with clinical and hematological findings and response to induction chemotherapy. Eighty-five patients with AL [45 with acute myeloid leukemia (AML) and 40 with acute lymphoblastic leukemia (ALL)] were used as a study group. Real-time PCR results showed that expression level of MDR1 was significantly higher in AML whereas expression of DHFR, BCRP and Survivin was significantly higher in ALL patients. In AML, significant correlation was observed between LRP and MRP1 (r(s)=0.44, p=0.016), LRP and DHFR (r(s)=0.41, p=0.02), MDR1 and BCL-2 (r(s)=0.38, p=0.03). Expression of GSTP1 and LRP correlated with high white blood count (p=0.03 and p=0.03) and BCL-2 with high peripheral blast count (p=0.009). MDR1 expression was significantly associated with the expression of immature stem cell marker CD34 (p=0.002). In ALL, significant association was found between LRP gene and female sex (p<0.0001), LRP and B-ALL patients (p=0.04) and LRP and BCR/ABL positive patients (p=0.004). High expression of MDR1 and BCL-2 in AML and MRP1 gene in ALL was associated with response to induction chemotherapy (p=0.001, p=0.02 and p=0.007 respectively). These results showed the potential clinical relevance of MDR1, MRP1 and BCL-2 in adult patients with acute leukemia in the context of induction chemotherapy.


Assuntos
Apoptose/genética , Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Subfamília B de Transportador de Cassetes de Ligação de ATP , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Regulação Neoplásica da Expressão Gênica , Genes bcl-2/genética , Humanos , Quimioterapia de Indução , Leucemia Mieloide Aguda/genética , Masculino , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Mutação , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , RNA Neoplásico/genética , Adulto Jovem
12.
PLoS One ; 6(12): e29431, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22206016

RESUMO

Complex disease such as cancer results from interactions of multiple genetic and environmental factors. Studying these factors singularly cannot explain the underlying pathogenetic mechanism of the disease. Multi-analytical approach, including logistic regression (LR), classification and regression tree (CART) and multifactor dimensionality reduction (MDR), was applied in 188 lung cancer cases and 290 controls to explore high order interactions among xenobiotic metabolizing genes and environmental risk factors. Smoking was identified as the predominant risk factor by all three analytical approaches. Individually, CYP1A1*2A polymorphism was significantly associated with increased lung cancer risk (OR = 1.69;95%CI = 1.11-2.59,p = 0.01), whereas EPHX1 Tyr113His and SULT1A1 Arg213His conferred reduced risk (OR = 0.40;95%CI = 0.25-0.65,p<0.001 and OR = 0.51;95%CI = 0.33-0.78,p = 0.002 respectively). In smokers, EPHX1 Tyr113His and SULT1A1 Arg213His polymorphisms reduced the risk of lung cancer, whereas CYP1A1*2A, CYP1A1*2C and GSTP1 Ile105Val imparted increased risk in non-smokers only. While exploring non-linear interactions through CART analysis, smokers carrying the combination of EPHX1 113TC (Tyr/His), SULT1A1 213GG (Arg/Arg) or AA (His/His) and GSTM1 null genotypes showed the highest risk for lung cancer (OR = 3.73;95%CI = 1.33-10.55,p = 0.006), whereas combined effect of CYP1A1*2A 6235CC or TC, SULT1A1 213GG (Arg/Arg) and betel quid chewing showed maximum risk in non-smokers (OR = 2.93;95%CI = 1.15-7.51,p = 0.01). MDR analysis identified two distinct predictor models for the risk of lung cancer in smokers (tobacco chewing, EPHX1 Tyr113His, and SULT1A1 Arg213His) and non-smokers (CYP1A1*2A, GSTP1 Ile105Val and SULT1A1 Arg213His) with testing balance accuracy (TBA) of 0.6436 and 0.6677 respectively. Interaction entropy interpretations of MDR results showed non-additive interactions of tobacco chewing with SULT1A1 Arg213His and EPHX1 Tyr113His in smokers and SULT1A1 Arg213His with GSTP1 Ile105Val and CYP1A1*2C in nonsmokers. These results identified distinct gene-gene and gene environment interactions in smokers and non-smokers, which confirms the importance of multifactorial interaction in risk assessment of lung cancer.


Assuntos
Mineração de Dados/métodos , Interação Gene-Ambiente , Neoplasias Pulmonares/genética , Fumar , Adulto , Idoso , Idoso de 80 Anos ou mais , Citocromo P-450 CYP1A1/genética , Epóxido Hidrolases/genética , Reações Falso-Positivas , Predisposição Genética para Doença , Haplótipos/genética , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Redução Dimensional com Múltiplos Fatores , Polimorfismo de Nucleotídeo Único/genética , Probabilidade , Reprodutibilidade dos Testes , Tamanho da Amostra , Fumar/efeitos adversos , Estatísticas não Paramétricas
13.
DNA Cell Biol ; 30(1): 39-46, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20731606

RESUMO

Polymorphisms in genes encoding detoxification enzymes have been suggested as susceptibility factors for many solid tumors. However, their association with hematological malignancies is controversial. A case-control study was done to determine the association between glutathione S-transferase M1 (GSTM1), GSTT1, GSTP1, EPHX1, and p53 codon 72 polymorphisms as risk factors in 120 adult acute myeloid leukemia (AML) cases and 202 healthy controls by polymerase chain reaction-restriction fragment length polymorphism techniques. Data were analyzed using χ(2) and conditional logistic regression model. None of the polymorphisms studied alone was associated with increased risk for AML. However, the frequency of GSTT1 null genotype was higher among controls (28.7%) than AML cases (21.6%), which showed a protective effect of the null genotype (odds ratio = 0.58, 95% confidence interval: 0.33-1.05, p = 0.07). In a combined analysis, both EPHX1 (His113His) and GSTP1 (Ile/Val) genes imparted a fourfold risk for adult AML but did not reach statistical significance (odds ratio = 4.22, 95% confidence interval: 0.992-17.99, p = 0.05). These findings suggest that the etiology of adult AML cannot be explained by polymorphism at a single locus, perhaps because of complexity involved in the metabolism of diverse xenobiotic compounds, and therefore, multiple gene-gene interactions should be investigated to predict the risk of AML.


Assuntos
Códon/genética , Epóxido Hidrolases/genética , Glutationa Transferase/genética , Leucemia Mieloide Aguda/genética , Polimorfismo Genético , Proteína Supressora de Tumor p53/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Epóxido Hidrolases/metabolismo , Feminino , Predisposição Genética para Doença/genética , Genótipo , Glutationa Transferase/metabolismo , Humanos , Leucemia Mieloide Aguda/metabolismo , Masculino , Pessoa de Meia-Idade , Proteína Supressora de Tumor p53/metabolismo , Xenobióticos/metabolismo , Adulto Jovem
14.
Genet Test Mol Biomarkers ; 14(5): 715-23, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20854097

RESUMO

BACKGROUND: Widespread use of tobacco and betel quid consumption and a high incidence of tobacco-associated aerodigestive tract cancers have been reported in different ethnic groups from several regions of Northeast (NE) India. This study was done to explore the possibility of phase II metabolic enzymes being responsible for the high prevalence of cancers in this region of India. METHODS: Samples from 370 cases with oral, gastric, and lung cancers and 270 controls were analyzed for polymorphism of glutathione-S-transferase (GST) genes using polymerase chain reaction-restriction fragment length polymorphism-based methods. RESULTS AND CONCLUSIONS: Tobacco smoking and betel quid chewing were found to be high risk factors for oral and lung cancers but not for gastric cancer, whereas tobacco chewing was found to be a risk factor for oral cancer but not for gastric or lung cancer. The variant genotypes of GSTP1 were not associated with any of the aerodigestive tract cancers. GSTT1 and GSTM1 null genotypes appeared to play a protective role for lung cancer (odds ratio [OR] = 0.47, 95% confidence interval [95% CI]: 0.24-0.93, p = 0.03) and (OR = 0.52, 95% CI: 0.28-0.96, p = 0.04), but they were not associated with oral and gastric cancers. However, when data was analyzed in different geographic regions the GSTT1 null genotype was found to be a significant risk factor for oral (OR = 2.58, 95% CI 1.01-6.61, p = 0.05) as well as gastric cancer (OR = 3.08, 95% CI 1.32-7.19, p = 0.009) in samples obtained from the Assam region of NE India. This is the first study on the association of GST polymorphisms and aerodigestive tract cancers in the high-risk region of NE India.


Assuntos
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Glutationa S-Transferase pi/genética , Glutationa Transferase/genética , Neoplasias Pulmonares/genética , Neoplasias Bucais/genética , Polimorfismo de Nucleotídeo Único , Neoplasias Gástricas/genética , Adenocarcinoma/epidemiologia , Adenocarcinoma/etiologia , Adulto , Idoso , Areca/efeitos adversos , Biotransformação , Carcinógenos/farmacocinética , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Feminino , Frequência do Gene , Predisposição Genética para Doença/genética , Genótipo , Hábitos , Humanos , Índia/epidemiologia , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/epidemiologia , Neoplasias Bucais/etiologia , Prevalência , Fatores de Risco , Fatores Socioeconômicos , Neoplasias Gástricas/epidemiologia , Neoplasias Gástricas/etiologia , Nicotiana/efeitos adversos
15.
Genet Test Mol Biomarkers ; 14(2): 163-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20073549

RESUMO

BACKGROUND: Detoxifying glutathione S-transferase (GST) gene polymorphisms show variation in different ethnic populations. GST detoxifies and metabolizes carcinogens, including oxygen free radicals. GST polymorphisms have been associated with susceptibility to different diseases. In the current study, allelic polymorphisms of GSTM1 and GSTT1 were analyzed in three ethnic groups of North East (NE) India where a high prevalence of various cancers and other diseases such as hypertension, tuberculosis, and asthma have been reported. METHODS: We compared the prevalence of GSTT1 and GSTM1 deletion genotypes, which were determined by multiplex polymerase chain reaction, in 422 voluntary, healthy NE Indians with those of other populations. The data was statistically analyzed. RESULTS: The GSTT1-null genotype was found in 51%, 34.3%, and 15.7% of individuals (from Mizoram, Sikkim, and Assam regions of NE India, respectively), whereas the GSTM1-null genotype was found in 46.9%, 46%, and 35% of individuals from the same areas. CONCLUSIONS: The NE Indians differ from the rest of the Indian population with reference to genotypic distribution of GST polymorphisms but the frequency was found to be similar to that which has been reported from China. This may explain the hypothesis of the common ancestral origin of both the NE Indians and the Chinese and a higher frequency of cancers such as gastric, esophageal, and oral cancers, which has been reported from these regions. This study establishes baseline frequency data for GST polymorphisms for future case control studies on the role these polymorphisms play with regard to diseases. The results presented here provide the first report on GST polymorphisms in the NE Indian population.


Assuntos
Glutationa Transferase/genética , Sequência de Bases , Primers do DNA/genética , Etnicidade/genética , Feminino , Deleção de Genes , Frequência do Gene , Predisposição Genética para Doença , Glutationa Transferase/metabolismo , Humanos , Inativação Metabólica/genética , Inativação Metabólica/fisiologia , Índia , Masculino , Neoplasias/enzimologia , Neoplasias/genética , Polimorfismo Genético
16.
Clin Exp Med ; 10(1): 33-40, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19779962

RESUMO

Occurrence of aberrant phenotypes in childhood and adult acute leukemia (AL) differs considerably in independent studies and their association with prognostic factors is still controversial. In the present study, 214 patients with AL (106 children and 108 adults) were evaluated for the aberrant expression of CD33 in ALL (B cell and T cell) and CD3, CD5, CD7, and CD19 in AML. In B-ALL, aberrant expression of CD33 was found in 39 and 23% cases of adult and children, respectively. In T-ALL, CD33 was seen in 33% cases of adults while in children CD33 was not observed. In AML, aberrant expression of CD19 was expressed in 52 and 32% while CD7 was expressed in 14 and 15% cases of childhood and adult AML, respectively. Among FAB subtypes, aberrant expression of CD19 and CD7 was more commonly seen in M5 subtype. One adult patient (AML-M5) showed expression of CD3, CD5, and CD19. In summary, aberrant phenotype was commonly seen in adults than childhood B-ALL while in AML, aberrant phenotype was more common in children than adults. CD19 was most commonly expressed antigen followed by CD7 in both childhood and adult AML. Interestingly, aberrant phenotype was not found in childhood T-ALL; however, it was seen in 33% cases of adults. We did not find any association of aberrant phenotype with adverse prognosis factors, CD34 marker, and clinical outcome except the absence of auer rod which was found to be significantly associated with aberrant phenotype of childhood AML (P = 0.01).


Assuntos
Leucemia Mieloide Aguda/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Adolescente , Adulto , Antígenos CD/biossíntese , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , Prognóstico , Resultado do Tratamento , Adulto Jovem
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