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1.
Discov Med ; 36(186): 1513-1526, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39054721

RESUMO

BACKGROUND: In recent years, various coronaviruses have caused severe respiratory illnesses worldwide. For example the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections of COVID-19 outbreak in 2019 in Wuhan, China. Genome-wide association studies (GWAS) have significantly expanded our comprehension of how specific genetic variations are linked to diseases. Research has demonstrated the existence of genetic factors influencing susceptibility to coronaviruses. The objective of this study was to examine the association of certain loci with the COVID-19 in Saudi population. METHODS: In the present study we have examined the link between the COVID-19 disease and certain genetic variants in hospitalized COVID-19 patients (n = 16) in Tabuk and Bisha, Kingdom Saudi Arabia. We used the genome Analysis Toolkit (GATK) and Comprehensive variant annotation was performed different databases and tools such as Search Tool for the Retrieval of Interacting Genes (STRING), PanelApp and PolyPhen-2. RESULTS: The study showed that the genetic variants associated with genes such as Homeostatic Iron Regulator (HFE) (found in 7 patients, representing 44%), complement factor H (CFH) (6 patients, 38%), cadherin 23 (CDH23) (4 patients, 25%), cytotoxic T-lymphocyte associated protein 4 (CTLA-4) (3 patients, 19%), Transforming Growth Factor Beta 1 (TGFB1) (3 patients, 19%), CREB-binding protein (CREBBP) (2 patients, 13%), E1A Binding Protein P300 (EP300) (2 patients, 13%), hemoglobin subunit beta (HBB) (2 patients, 13%), interferon regulatory factor 7 (IRF7) (2 patients, 13%), and unc-119 lipid binding chaperone (UNC119) (2 patients, 13%) might be associated with susceptibility to coronavirus. We also identified mutations in the COVID-19 patient that are pathogenic or likely pathogenic. CONCLUSION: A recurrent pathogenic mutation, HFE p.His63Asp (H63D), was identified in 7 patients, suggesting its potential contribution to disease severity. Additionally, a likely pathogenic variant, HBB p.Glu7Val (E7V), was present in 2 patients, highlighting its potential role in disease susceptibility. Our results shed light on the key genetic mechanisms of COVID-19 pathogenesis and help to identify and stratify the individuals or populations that are at risk to corona virus infection. The identification of susceptible individuals or populations assist in prevention and/or in treatment programs.


Assuntos
COVID-19 , Sequenciamento do Exoma , Proteína da Hemocromatose , SARS-CoV-2 , Humanos , COVID-19/genética , COVID-19/virologia , COVID-19/mortalidade , SARS-CoV-2/genética , Masculino , Pessoa de Meia-Idade , Feminino , Arábia Saudita/epidemiologia , Proteína da Hemocromatose/genética , Adulto , Predisposição Genética para Doença , Idoso , Mutação , Estudo de Associação Genômica Ampla
2.
Molecules ; 29(8)2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38675722

RESUMO

Diabetes mellitus (DM) represents a problem for the healthcare system worldwide. DM has very serious complications such as blindness, kidney failure, and cardiovascular disease. In addition to the very bad socioeconomic impacts, it influences patients and their families and communities. The global costs of DM and its complications are huge and expected to rise by the year 2030. DM is caused by genetic and environmental risk factors. Genetic testing will aid in early diagnosis and identification of susceptible individuals or populations using ATP-sensitive potassium (KATP) channels present in different tissues such as the pancreas, myocardium, myocytes, and nervous tissues. The channels respond to different concentrations of blood sugar, stimulation by hormones, or ischemic conditions. In pancreatic cells, they regulate the secretion of insulin and glucagon. Mutations in the KCNJ11 gene that encodes the Kir6.2 protein (a major constituent of KATP channels) were reported to be associated with Type 2 DM, neonatal diabetes mellitus (NDM), and maturity-onset diabetes of the young (MODY). Kir6.2 harbors binding sites for ATP and phosphatidylinositol 4,5-diphosphate (PIP2). The ATP inhibits the KATP channel, while the (PIP2) activates it. A Kir6.2 mutation at tyrosine330 (Y330) was demonstrated to reduce ATP inhibition and predisposes to NDM. In this study, we examined the effect of mutations on the Kir6.2 structure using bioinformatics tools and molecular dynamic simulations (SIFT, PolyPhen, SNAP2, PANTHER, PhD&SNP, SNP&Go, I-Mutant, MuPro, MutPred, ConSurf, HOPE, and GROMACS). Our results indicated that M199R, R201H, R206H, and Y330H mutations influence Kir6.2 structure and function and therefore may cause DM. We conclude that MD simulations are useful techniques to predict the effects of mutations on protein structure. In addition, the M199R, R201H, R206H, and Y330H variant in the Kir6.2 protein may be associated with DM. These results require further verification in protein-protein interactions, Kir6.2 function, and case-control studies.


Assuntos
Diabetes Mellitus , Simulação de Dinâmica Molecular , Canais de Potássio Corretores do Fluxo de Internalização , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/química , Humanos , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Mutação , Predisposição Genética para Doença , Sítios de Ligação , Ligação Proteica
3.
Curr Issues Mol Biol ; 45(9): 7449-7475, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37754255

RESUMO

Type 2 diabetes (T2D) develops from insulin resistance (IR) and the dysfunction of pancreatic beta cells. The AKT2 protein is very important for the protein signaling pathway, and the non-synonymous SNP (nsSNPs) in AKT2 gene may be associated with T2D. nsSNPs can result in alterations in protein stability, enzymatic activity, or binding specificity. The objective of this study was to investigate the effect of nsSNPs on the AKT2 protein structure and function that may result in the induction of IR and T2D. The study identified 20 variants that were considered to be the most deleterious based on a range of analytical tools included (SIFT, PolyPhen2, Mut-pred, SNAP2, PANTHER, PhD-SNP, SNP&Go, MUpro, Cosurf, and I-Mut). Two mutations, p.A179T and p.L183Q, were selected for further investigation based on their location within the protein as determined by PyMol. The results indicated that mutations, p.A179T and p.L183Q alter the protein stability and functional characteristics, which could potentially affect its function. In order to conduct a more in-depth analysis of these effects, a molecular dynamics simulation was performed for wildtype AKT2 and the two mutants (p.A179T and p.L183Q). The simulation evaluated various parameters, including temperature, pressure, density, RMSD, RMSF, SASA, and Region, over a period of 100 ps. According to the simulation results, the wildtype AKT2 protein demonstrated higher stability in comparison to the mutant variants. The mutations p.A179T and p.L183Q were found to cause a reduction in both protein stability and functionality. These findings underscore the significance of the effects of nsSNPs (mutations p.A179T and p.L183Q) on the structure and function of AKT2 that may lead to IR and T2D. Nevertheless, they require further verifications in future protein functional, protein-protein interaction, and large-scale case-control studies. When verified, these results will help in the identification and stratification of individuals who are at risk of IR and T2D for the purpose of prevention and treatment.

4.
Biomed Pharmacother ; 150: 113054, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35658225

RESUMO

Cancer is one of the leading causes of death and significantly burdens the healthcare system. Due to its prevalence, there is undoubtedly an unmet need to discover novel anticancer drugs. The use of natural products as anticancer agents is an acceptable therapeutic approach due to accessibility, applicability, and reduced cytotoxicity. Natural products have been an incomparable source of anticancer drugs in the modern era of drug discovery. Along with their derivatives and analogs, natural products play a major role in cancer treatment by modulating the cancer microenvironment and different signaling pathways. These compounds are effective against several signaling pathways, mainly cell death pathways (apoptosis and autophagy) and embryonic developmental pathways (Notch pathway, Wnt pathway, and Hedgehog pathway). The historical record of natural products is strong, but there is a need to investigate the current role of natural products in the discovery and development of cancer drugs and determine the possibility of natural products being an important source of future therapeutic agents. Many target-specific anticancer drugs failed to provide successful results, which accounts for a need to investigate natural products with multi-target characteristics to achieve better outcomes. The potential of natural products to be promising novel compounds for cancer treatment makes them an important area of research. This review explores the significance of natural products in inhibiting the various signaling pathways that serve as drivers of carcinogenesis and thus pave the way for developing and discovering anticancer drugs.


Assuntos
Antineoplásicos , Produtos Biológicos , Neoplasias , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Proteínas Hedgehog , Humanos , Neoplasias/tratamento farmacológico , Microambiente Tumoral , Via de Sinalização Wnt
5.
J Pers Med ; 12(4)2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35455754

RESUMO

Diabetes mellitus constitutes a big challenge to the global health care system due to its socioeconomic impacts and very serious complications. The incidence and the prevalence rate are increased in the Gulf region including the KSA. Type 2 diabetes mellitus (T2DM) is caused by diverse risk factors including obesity, unhealthy dietary habits, physical inactivity, smoking and genetic factors. The molecular genetic studies have helped in the detection of many single nucleotide polymorphisms (SNP) with different diseases including cancers, cardiovascular diseases and T2DM. The glyoxalase 1 (GLO1) is a detoxifying enzyme and catalyzes the elimination of the cytotoxic product methylglyoxal (MG) by converting it to D-lactate, which is not toxic to tissues. MG accumulation is associated with the pathogenesis of different diseases including T2DM. In this study, we have investigated the association of the glyoxalase 1 SNPs (rs2736654) rs4746 C>A and rs1130534 T>A with T2DM using the amplification refractory mutation system PCR. We also measured the concentration of MG by ELISA in T2DM patients and matched heathy controls. Results show that the CA genotype of the GLO rs4647 A>C was associated with T2DM with OR = 2.57, p-value 0.0008 and the C allele was also associated with increased risk to T2DM with OR = 2.24, p-value = 0.0001. It was also observed that AT genotype of the rs1130534 was associated with decreased susceptibility to T2DM with OR = 0.3, p-value = 0.02. The A allele of rs1130534 was also associated with reduced risk to T2DM with PR = 0.27 = 0.006. In addition, our ELISA results demonstrate significantly increased MG concentrations in serum of the T2DM patients. We conclude that the GLO1 SNP may be associated with decreased enzyme activity and a resultant susceptibility to T2DM. Further well-designed studies in different and large patient populations are recommended to verify these findings.

6.
Indian J Hematol Blood Transfus ; 37(1): 21-29, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33707832

RESUMO

Inherited polymorphic sequence variations in drug transport genes like ABCB1 impact a portion of patients with hematologic malignancies that show intrinsic or acquire resistance to treatment. Keeping in view inter-individual sensitivities for such drugs, we through this case-control study tested whether ABCB1 C3435T and G2677T polymorphisms have any influence on the risk and treatment response in patients with chronic myeloid leukemia (CML) and B-acute lymphoblastic leukemia (B-ALL). Genotyping for ABCB1 polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism in 100 CML and 80 B-ALL patients along with 100 age and gender matched healthy controls. ABCB1 C3435T and G2677T polymorphism showed no association with CML. Genotype distribution revealed significant higher frequency of TT genotype for both SNPs in B-ALL cases and associated with increased B-ALL risk (OR 2.5, p = 0.04 for 3435TT; OR 2.4, p = 0.04 for 2677TT). There was no significant difference in genotype frequency of 3435C > T and 2677G > T among resistant and responsive groups for the two leukemia types. Kaplan-Meier survival plots revealed significantly lower event free survival in CML and B-ALL patients that were carriers of 3435TT genotype (p < 0.05). Multivariate analysis considered 3435TT genotype as independent risk factor for imatinib resistance in CML cases (HR 6.24, p = 0.002) and increased relapse risk in B-ALL patients (HR 4.51, p = 0.03). The current study provides preliminary evidence of a significant association between variant TT genotype and increased B-ALL risk. Also, results suggest that ABCB1 3435TT genotype increases imatinib resistance in CML and influence therapeutic outcome in B-ALL.

7.
Arch. endocrinol. metab. (Online) ; 64(5): 528-532, Sept.-Oct. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1131139

RESUMO

ABSTRACT Objective: The objective of this study is to study association between testosterone and diabetes in Kashmiri males. Subjects and methods: A total of 300 males with Type 2 diabetes visited an outpatient and inpatient clinic at Shri Maharaja Hari Singh (SMHS) hospital, Srinagar, J&K India. The blood sugar and HbA1c, which are the markers of diabetes, and sérum testosterone levels were measured. The blood samples from both the cases and controls were collected. Results: Out of 300 subjects, 42% had a testosterone deficiency. A relationship between type 2 diabetic males and healthy males was observed, and testosterone levels were determined to be significantly lower among diabetic males (p < 0.001) when compared to healthy males. Then, we compared diabetic markers among testosterone deficient and normal testosterone level groups; the mean fasting plasma glucose (p = 0.0019) and glycated haemoglobin (HbA1c; p = 0.0449) levels were significantly higher in the testosterone deficient group than in the control group. To elucidate the relationship between the serum total testosterone level and fasting plasma glucose and HbA1c values, Pearson's correlation test was performed. Fasting plasma glucose levels (r = −0.252, p = 0.001) and HbA1c values (r = −0.697, p = 0.001) showed a significant negative correlation with serum testosterone levels among diabetic males. Conclusions: This study shows that diabetes causes low testosterone levels among males, and lower testosterone levels can act as a marker for diabetes. Thus, with timely intervention, mortality and co-morbidity associated with diabetes can be prevented.


Assuntos
Humanos , Masculino , Diabetes Mellitus Tipo 2 , Testosterona , Glicemia , Hemoglobinas Glicadas/análise , Índia
8.
J Pers Med ; 9(4)2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31775219

RESUMO

MicroRNAs (miRNAs) are endogenous, small (18-23 nucleotides), non-coding RNA molecules. They regulate the posttranscriptional expression of their target genes. MiRNAs control vital physiological processes such as metabolism, development, differentiation, cell cycle and apoptosis. The control of the gene expression by miRNAs requires efficient binding between the miRNA and their target mRNAs. Genome-wide association studies (GWASs) have suggested the association of single-nucleotide polymorphisms (SNPs) with certain diseases in various populations. Gene polymorphisms of miRNA target sites have been implicated in diseases such as cancers, diabetes, cardiovascular and Parkinson's disease. Likewise, gene polymorphisms of miRNAs have been reported to be associated with diseases. In this review, we discuss the SNPs in miRNA genes that have been associated with diabetes and atherosclerotic cardiovascular disease in different populations. We also discuss briefly the potential underlining mechanisms through which these SNPs increase the risk of developing these diseases.

9.
Int J Biochem Cell Biol ; 115: 105589, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31442608

RESUMO

TNF receptor proteins were primarily recognized as adaptor proteins that ligate with the tumor necrosis factor receptor (TNFR)-associated factor (TNFR) family to execute various signaling pathways. However, recent studies showed that they act as a signal-transducing molecules and are reported to have a functional role as a Toll/interleukin-1 receptor family member. Seven members of this family have been identified to date. Among TNF receptor family, TRAF7 does not share a common TRAF domain homology. The tumor necrosis factor receptor associated factor (TRAF) domain comprises of about 230 amino acid motif at the C-terminal region that has the capability to bind TNFR and execute different downstream signaling pathways. Moreover, N-terminal RING and ZINC finger constituted by the tumor necrosis factor associated protein 2 and tumor necrosis factor associated protein 6 are critical and execute various downstream signaling events. TRAF proteins have emerged as critical regulators that provide the cellular response to stress and lead to cell death. Nuclear factor kappa beta (NF-KB) and c-Jun N-terminal kinases (JNK) pathways are activated through tumor necrosis factor associated protein 2, tumor necrosis factor associated protein 5 and tumor necrosis factor associated protein 6 members. TRAF proteins in pathogenesis were observed from their abnormal expression in diseased tissue and in normal tissue, suggesting its important role in physiological processes. Recently, unique specificity of TRAF4 for glycoprotein Ibß (GPIbß) and glycoprotein VI (GPVI) in human platelets has been reported. The multifunctional effects of TRAIP (TNF) interacting protein in many cellular signaling pathways emerged as very important signaling molecule. Furthermore, the new insights into the structure of TRAF members along with new studies involved in health and disease prompted to explore their role particularly the TNF receptor associated proteins with novel inhibitor protein TRAIP (TNF) interacting protein and human diseases associated with it. As such, this review emphasis on tumor necrosis factor receptor associated proteins, present their current understanding with novel inhibitor protein TRAIP (TNF) interacting protein.


Assuntos
Doença , Peptídeos e Proteínas Associados a Receptores de Fatores de Necrose Tumoral/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Animais , Humanos , Neoplasias/metabolismo
10.
BMC Cancer ; 12: 602, 2012 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-23244191

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) shows geographic variations in incidence, with high incidences (>50/105 person-years) in central Asia, including North Eastern Iran (Golestan) and Northern India (Kashmir). In contrast to Western countries, smoking does not appear to be a significant risk factor for ESCC in central Asia. In lung adenocarcinoma, activating mutations in the gene encoding epidermal growth factor receptor (EGFR) are frequent in tumors of never smokers of Asian origin, predicting therapeutic sensitivity to Egfr-targeting drugs. METHODS: In this study 152 cases of histologically confirmed ESCC from Iran (Tehran and Golestan Province) and North India (Kashmir Valley) have been analyzed for EGFR mutation by direct sequencing of exons 18-21. Egfr protein expression was evaluated by immunohistochemistry in 34 samples from Tehran and HER2 mutations were analyzed in 54 cases from Kashmir. RESULTS: A total of 14 (9.2%) EGFR variations were detected, including seven variations in exons. Among those, four (2.6%) were already documented in lung cancers, two were reported as polymorphisms and one was a potentially new activating mutation. All but one variation in introns were previously identified as polymorphisms. Over-expression of Egfr was detected in 22/34 (65%) of tested cases whereas no HER2 mutation was found in 54 cases from Kashmir. CONCLUSION: Overall, EGFR mutations appear to be a rare event in ESCC in high incidence areas of central Asia, although a very small proportion of cases may harbor mutations predicting sensitivity to anti-Egfr drugs.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/genética , Receptores ErbB/genética , Neoplasias Esofágicas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Ásia Central , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Análise Mutacional de DNA , Receptores ErbB/biossíntese , Neoplasias Esofágicas/metabolismo , Feminino , Genes erbB-1 , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase
11.
BMC Cancer ; 11: 27, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-21247504

RESUMO

BACKGROUND: Two clinically relevant high-risk HPV (HR-HPV) types 16 and 18 are etiologically associated with the development of cervical carcinoma and are also reported to be present in many other carcinomas in extra-genital organ sites. Presence of HPV has been reported in breast carcinoma which is the second most common cancer in India and is showing a fast rising trend in urban population. The two early genes E6 and E7 of HPV type 16 have been shown to immortalize breast epithelial cells in vitro, but the role of HPV infection in breast carcinogenesis is highly controversial. Present study has therefore been undertaken to analyze the prevalence of HPV infection in both breast cancer tissues and blood samples from a large number of Indian women with breast cancer from different geographic regions. METHODS: The presence of all mucosal HPVs and the most common high-risk HPV types 16 and 18 DNA was detected by two different PCR methods - (i) conventional PCR assays using consensus primers (MY09/11, or GP5+/GP6+) or HPV16 E6/E7 primers and (ii) highly sensitive Real-Time PCR. A total of 228 biopsies and corresponding 142 blood samples collected prospectively from 252 patients from four different regions of India with significant socio-cultural, ethnic and demographic variations were tested. RESULTS: All biopsies and blood samples of breast cancer patients tested by PCR methods did not show positivity for HPV DNA sequences in conventional PCRs either by MY09/11 or by GP5+/GP6+/HPV16 E6/E7 primers. Further testing of these samples by real time PCR also failed to detect HPV DNA sequences. CONCLUSIONS: Lack of detection of HPV DNA either in the tumor or in the blood DNA of breast cancer patients by both conventional and real time PCR does not support a role of genital HPV in the pathogenesis of breast cancer in Indian women.


Assuntos
Alphapapillomavirus/genética , Neoplasias da Mama/sangue , DNA Viral/sangue , Infecções por Papillomavirus/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Mama/patologia , Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Primers do DNA/genética , DNA Viral/genética , Feminino , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Infecções por Papillomavirus/epidemiologia , Reação em Cadeia da Polimerase/métodos
12.
Mol Carcinog ; 50(7): 487-98, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21268129

RESUMO

Investigation of potential association of SNPs (G870A, rs9344; G1722C, rs678653) of cyclin D1 gene (CCND1) with susceptibility to esophageal squamous cell carcinoma (ESCC) in Kashmir valley (India). The study included 302 subjects comprising 151 ESCC cases and 151 controls. PCR-RFLP and direct sequencing were employed for genotyping. The G870A polymorphism, the individuals carrying GA + AA genotype was having 2.80-fold increased risk for development of ESCC (OR 2.8, 95% CI = 1.77-4.4; P = 0.0001) compared to GG genotype. Further a significantly higher risk was observed in individuals who consume >3 cups per day of salted tea (OR = 5.1; 95% CI = 1.6-16.7; P = 0.0016) and had smoking habits (OR = 6.3; 95% CI = 2.9-13.9; P = 0.0005). We also demonstrate for the first time in CCND1 1722 locus, the CC genotype was strongly associated with increased risk of developing ESCC (OR = 2.58; 95% CI = 1.61-4.15; P = 0.0001). In addition, the frequency of polymorphic C allele was also found to be higher in cases (OR = 1.92; 95% CI = 1.37-2.69; P = 0.0002). There appears to be an influence of CCND1 G870A/G1772C genotypes on genetic susceptibility to ESCC.


Assuntos
Carcinoma de Células Escamosas/genética , Ciclina D1/genética , Neoplasias Esofágicas/genética , Polimorfismo de Nucleotídeo Único , Adulto , Carcinoma de Células Escamosas/epidemiologia , Eletroforese em Gel de Poliacrilamida , Neoplasias Esofágicas/epidemiologia , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Fatores de Risco
13.
BMC Cancer ; 9: 329, 2009 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-19758438

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a leading cause of cancer-related deaths in Jammu and Kashmir (J&K) region of India. A substantial proportion of esophageal carcinoma is associated with infection of high-risk HPV type 16 and HPV18, the oncogenic expression of which is controlled by host cell transcription factor Activator Protein-1 (AP-1). We, therefore, have investigated the role of DNA binding and expression pattern of AP-1 in esophageal cancer with or without HPV infection. METHODS: Seventy five histopathologically-confirmed esophageal cancer and an equal number of corresponding adjacent normal tissue biopsies from Kashmir were analyzed for HPV infection, DNA binding activity and expression of AP-1 family of proteins by PCR, gel shift assay and immunoblotting respectively. RESULTS: A high DNA binding activity and elevated expression of AP-1 proteins were observed in esophageal cancer, which differed between HPV positive (19%) and HPV negative (81%) carcinomas. While JunB, c-Fos and Fra-1 were the major contributors to AP-1 binding activity in HPV negative cases, Fra-1 was completely absent in HPV16 positive cancers. Comparison of AP-1 family proteins demonstrated high expression of JunD and c-Fos in HPV positive tumors, but interestingly, Fra-1 expression was extremely low or nil in these tumor tissues. CONCLUSION: Differential AP-1 binding activity and expression of its specific proteins between HPV--positive and HPV--negative cases indicate that AP-1 may play an important role during HPV-induced esophageal carcinogenesis.


Assuntos
Alphapapillomavirus/fisiologia , Carcinoma de Células Escamosas/metabolismo , Neoplasias Esofágicas/metabolismo , Regulação Neoplásica da Expressão Gênica , Infecções por Papillomavirus/metabolismo , Fator de Transcrição AP-1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virologia , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/virologia , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/genética , Infecções por Papillomavirus/virologia , Ligação Proteica , Fator de Transcrição AP-1/genética
14.
Mol Cell Biochem ; 332(1-2): 51-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19513816

RESUMO

Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent cancer in Jammu and Kashmir region of India and has multi-factorial etiology involving dietary habits, genetic factors, and gene environmental interactions. Inactivation of the p16 gene expression by aberrant promoter methylation plays an important role in the progression of esophageal carcinoma. In the present investigation, we have studied the role of p16 promoter methylation in 69 histopathologically confirmed ESCC tissues and compared it with corresponding normal adjacent tissues for DNA methylation in the CpG island in the p16 promoter region by methylation-specific polymerase chain reaction (MSP) and p16 protein expression by immunoblotting. The results showed loss of p16 expression in 67% (46/69) of tumor tissues compared to only 3% in control tissues (2/69). Promoter methylation was observed in 52% (36/69) of tumor tissues and it gradually increased with the increasing severity of histological grades of the cancer (P = 0.0001). Loss of p16 expression with promoter methylation was observed in 26 of 36 cases (72%). Analysis of patients dietary habits revealed a strong association between promoter methylation and high consumption of hot salted tea (P < 0.05) which is a most favourite drink commonly consumed by Kashmiri people.


Assuntos
Carcinoma de Células Escamosas/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Metilação de DNA , Neoplasias Esofágicas/genética , Regiões Promotoras Genéticas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Diferenciação Celular , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Feminino , Inativação Gênica , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
15.
Nutr Cancer ; 60(5): 585-91, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18791921

RESUMO

Trace element deficiency or excess is implicated in the development or progression in some cancers. Here we report the elevated level of copper and low level of zinc in the plasma of esophageal cancer patients in Kashmir India--a high incidence area. The average level of copper was significantly higher (P < 0.0001) for patients than for controls, with a mean concentration of 169 microg/dl and 149 microg/dl for patients and controls, respectively. The control group consisted of 55 healthy individuals matched for age, sex, and place of residence of the patients. In contrast, the average level of zinc in patients was significantly lower than in controls (P < 0.0001), with a mean concentration of 86.8 microg/dl and 96.1 microg/dl for patients and controls, respectively. The levels of both copper and zinc showed significant differences based on gender and age in patients as compared to controls. Similarly, smokers depicted a significant increase in serum copper (N = 39, P = 0.002) and a decrease in serum zinc approaching level of significance in the patient group as compared to controls. The copper and zinc levels were significantly altered in patients (N = 40) when compared to controls as a function of snuff consumption. The differences in the levels of copper and zinc showed significant association with the consumption of local salted tea up to 1,500 ml per day, but the changes were insignificant beyond that. Patients with poorly differentiated tumors (N = 7) had a higher copper concentration than those with moderately or well-differentiated tumors (P < 0.0001). To validate the general notion that imbalance in copper and zinc levels may lead to higher prevalence of TP53 mutations, we compared the 3 variables, and no association was found between copper concentration and TP53 mutation status; but patients with TP53 mutant tumor had lower zinc levels than those with no mutation. In conclusion, our results point toward a role of the trace element imbalance in the esophageal tumorigenesis in high-risk Kashmiri population exposed to a range of nitroso compounds or their precursors. Further prospective cohort studies are warranted to determine whether change in the plasma zinc and copper homeostasis may represent an independent risk factor for this malignancy as well as a possible target for preventive intervention.


Assuntos
Carcinoma de Células Escamosas/epidemiologia , Cobre/toxicidade , Neoplasias Esofágicas/epidemiologia , Neoplasias Esofágicas/genética , Genes p53/genética , Mutação/genética , Zinco/deficiência , Adulto , Idoso , Bebidas , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Comorbidade , Cobre/sangue , Neoplasias Esofágicas/patologia , Feminino , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco , Fumar/epidemiologia , Cloreto de Sódio na Dieta , Tabaco sem Fumaça , Oligoelementos/deficiência , Oligoelementos/toxicidade , Zinco/sangue
16.
Int J Health Sci (Qassim) ; 2(2): 17-25, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21475485

RESUMO

Activating mutations in Epidermal Growth Factor Receptor (EGFR) are common in lung adenocarcinoma of never smokers but are rare in other types of cancer. Here we have analysed mutations in exons 19 to 21 of EGFR and in exons 19 and 20 of the EGFR homolog HER2 in 54 cases of Esophageal Squamous Cell Carcinomas (ESCC) from patients recruited in Kashmir, India, a region of high incidence for this cancer. We report the detection of 3 mutations (6%) in the ATP-binding regulatory loops of the tyrosine kinase domain of EGFR (deletion 746-750, P753L, G719D). No mutation was found in HER2. This is the first report of activating EGFR mutations in ESCC, of the same type as those detected in lung adenocarcinoma of never-smokers. This suggests that a small proportion of ESCC patients in this high incidence area may benefit from treatment with EGFR tyrosine kinase inhibitors.

17.
Int J Health Sci (Qassim) ; 1(2): 177-83, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21475426

RESUMO

BACKGROUND: Esophageal cancer (EC) is the sixth leading cause of death from cancer. In high-risk regions, squamous cell carcinoma is the most common type of EC, and its etiology remains poorly understood. It shows uneven geographical distribution in its occurrence, reflecting the influence of local environmental conditions, lifestyle and genetic predisposition in the development of the cancer. Kashmir, in the north of India, has been described as a high-risk area for esophageal squamous cell carcinoma (ESCC). In the present investigation an attempt was made to study the role of ß-catenin mutations and human papillomavirus in 62 ESCC patients from Kashmir. METHODS: The hot spot mutation region of ß-catenin exon 3 was evaluated in matched tumor and normal tissues using a combination of PCR-SSCP and direct sequencing. We used two different sets of consensus primers viz., GP5+ and GP6+; PGMY09 and PGMY11 in conjunction with reverse line blot assay to screen for human papillomavirus(HPV). RESULTS: None of the tumors showed the presence of commonly reported mutations in ß-catenin. In view of the fact that HPV has been linked to pathogenesis of EC, we screened all the tumor and control specimens for the presence of HPV and we didn't detect HPV in any of the matched tumor and control specimens in contrast to the positive controls we used. CONCLUSION: In conclusion our results suggest that squamous cell carcinoma of esophagus in Kashmir may arise independent of oncogenic ß-catenin mutations and HPV is unlikely to be an etiologic factor for ESCC in this region.

18.
Int J Health Sci (Qassim) ; 1(1): 35-42, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21475450

RESUMO

Trace element deficiency or excess is implicated in the development or progression in some cancers. Here we report the elevated levels of copper and low level of zinc in the plasma of esophageal cancer patients in Kashmir India- a high incidence area. The average level of copper was significantly higher for patients than for controls (p<0.0001) with a mean concentration of 169 µg/dl and 149 µg/dl for patients and controls, respectively. In contrast, the average level of zinc in patients was significantly lower than in controls (p<0.0001) with a mean concentration of 86.8 µg/dl and 96.1 µg/dl for patients and controls, respectively. No significant difference in copper and zinc levels was observed for different age groups in controls or patients. For controls, the level of copper was not significantly different in males and females (median: 155 µg/dl for males and 144 µg/dl for females, p=0.10), but we observed a higher level of zinc in females (median: 90.5 µg/dl for males and 101 µg/dl for females, p=0.03). Copper or zinc concentrations were not significantly associated with gender, tumor site, green tea with salt (nun chai) consumption, smoking habits or snuff in cases. Patients with poorly differentiated tumors had a higher copper concentration than those with moderately or well-differentiated tumors (p<0.0001). No association was found between copper concentration and TP53 mutation status but patients with TP53 mutant tumor had lower zinc levels than those with no mutation. Our results point towards a role of the trace element imbalance in the esophageal tumorigenesis in high risk Kashmiri population exposed to a range of nitroso compounds or their precursors. Further prospective cohort studies are warranted to determine whether change in the plasma zinc and copper homeostasis may represent an independent risk factor for this malignancy as well as possible target for preventive intervention.

19.
Int J Cancer ; 116(1): 62-8, 2005 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-15761872

RESUMO

Esophageal squamous cell carcinoma (ESCC) has been reported to show geographical variation in its incidence, even within areas of ethnic homogeneity. Kashmir valley, in north of India, has been described as a high-risk area for ESCC. Here, we make a preliminary attempt to study mutations in exons 5-8 (the DNA binding domain) of the tumor suppressor gene, p53, in 55 ESCC patients from Kashmir. Polymerase chain reaction followed by direct sequencing analysis revealed the presence of mutations in 36.36% (20/55) tumors, assessed for the extent of allelic instability. The 20 mutations, found in 20 patients, comprised of 17 single-base substitutions (11 transitions + 6 transversions) and 3 deletions. The 17 single-base variations represented 12 missense mutations, 2 nonsense mutations and 3 variations located in intron 6, 1 of which resulted in a splicing variant. The patients when compared for the incidence of p53 mutation with various demographic features revealed females to be at increased risk (p = 0.016; OR = 4.13; 95% CI = 1.26-13.46). Comparison of mutation profile with other high-risk areas reflected both differences and similarities indicating coexposure to a unique set of risk factors. This might be due to the special dietary and cultural practices of Kashmir that needs validation, as does the gender-based difference in the incidence of p53 mutation observed in this study.


Assuntos
Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Genes p53 , Mutação , Adulto , Idoso , Carcinoma de Células Escamosas/epidemiologia , Neoplasias Esofágicas/epidemiologia , Feminino , Humanos , Índia/epidemiologia , Perda de Heterozigosidade , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Fatores de Risco , Fatores Sexuais
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