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1.
Indian J Public Health ; 68(3): 366-373, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39321224

RESUMO

BACKGROUND: Thalassemia is an inherited blood disorder characterized by abnormal production of hemoglobin. The prevalence of thalassemia in India varies depending on the region and population. The study used a pre- and postcounseling cross-sectional design, which involves measuring outcomes before and after the intervention (genetic counseling). OBJECTIVES: Three hundred and eighty-five respondents were screened as thalassemia carriers, between a pool of 2985 participants to depict the quantitative prevalence of thalassemia. Two separate qualitative cross-sectional studies were conducted and compared to validate genetic counseling. The aims of the study are to contribute to the understanding of thalassemia carrier frequency and to improve the education and awareness of college students regarding thalassemia. MATERIALS AND METHODS: Two different questionnaires were used with the same knowledge, attitude, and practice parameters, one before and one after counseling. A two-sample t-test and an analysis of variance (ANOVA) F-test were used to compare the changes in knowledge, attitude, and practice. RESULTS: Using paired samples t-test to compare the pre- and postcounseling outcome showed significant (P < 0.001) elevation in terms of knowledge, attitude, social beliefs, social discomfort, and practice as a thalassemia carrier. Further, ANOVA F-test demonstrates the relationship between demography and the difference in parametric score of the pre- and postcounseling outcome. CONCLUSION: By improving knowledge and attitudes, counseling can help individuals to better understand their condition and the importance of adhering to treatment recommendations. This can lead to improved health outcomes and a better quality of life for affected individuals.


Assuntos
Aconselhamento Genético , Conhecimentos, Atitudes e Prática em Saúde , Talassemia beta , Humanos , Índia/epidemiologia , Talassemia beta/genética , Estudos Transversais , Masculino , Feminino , Adulto , Estudantes/psicologia , Adulto Jovem , Heterozigoto
2.
Curr Microbiol ; 80(8): 252, 2023 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-37354374

RESUMO

Microbial fuel cells (MFCs) function by using microorganisms to decompose the substrate at the anode, producing electrons and protons. These charges are then transported to the cathode, where electricity is generated. Previous studies have shown their promising probabilities for practical applications. MFCs are praised for their ability to address energy shortages and environmental pollution simultaneously. They have the potential to generate electricity directly from organic substances, reducing energy losses that occur during intermediate conversion steps. The main challenge lies in transitioning these technologies from the laboratory setting to practical systems that can be implemented on a large scale for bioenergy production along with various engineering hurdles. This study focused on investigating the power production potential of a soil-isolated bacterial strain taxonomically classified as Lysinibacillus xylanilyticus nbpp1, which is a relatively new addition to the extensive range of biocatalysts known for their ability to generate electricity. The study analyzed the electrochemical performance of an H-type MFC setup. LB broth was used as the substrate, while aluminum and graphite served as electrode materials. Other parameters, such as Coulombic efficiency, internal resistance, and electrode corrosion rate, were also measured. The MFC produced a high open circuit voltage of 1127 mV and achieved a maximum power density of 6.71 mW/cm2 at a current density of 11.14 mA/cm2. The MFC setup successfully powered LED lamps when connected in a joint circuit, showcasing its potential for practical applications. These findings suggest the promising high electrochemical performance of the MFC system in terms of electricity generation using the specified conditions.


Assuntos
Bacillaceae , Fontes de Energia Bioelétrica , Fontes de Energia Bioelétrica/microbiologia , Eletricidade , Bactérias/química , Eletrodos
3.
Curr Microbiol ; 77(10): 3125-3135, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32725340

RESUMO

An exopolysaccharide (EPS-I) having the molecular weight ~ 2.6 × 105 Da, was isolated from a Zinc resistant strain of Enterococcus faecalis from costal area. The exopolysaccharide consists of D-mannose, D-glucose, and L-fucose in molar ratio of 9:4:1. The monosaccharide units in the EPS-1 were determined through chemical (total acid hydrolysis and methylation analysis) and spectroscopic (FTIR and 1H NMR experiment) analysis. The mannose-rich EPS-1 showed total antioxidant activity (1 mg mL-1 of EPS-I as functional as approximately to 500 ± 5.2 µM of ascorbic acid) and Fe2+ metal ion chelation activity (EC50 = 405.6 µg mL-1) and hydroxyl radical scavenging activity (EC50 = 219.5 µg mL-1). The in vitro cytotoxicity experiment of EPS-I against cervical carcinoma cell line, HeLa cells showed strong cytotoxic effect (LC50 = 267.3 µg mL-1) and at that concentration, it found almost nontoxic against normal healthy cells (HEK-293).


Assuntos
Antioxidantes , Enterococcus faecalis , Antioxidantes/farmacologia , Células HEK293 , Células HeLa , Humanos , Polissacarídeos Bacterianos
4.
Org Biomol Chem ; 14(2): 570-576, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26510406

RESUMO

H2S is shown, for the first time, to play an extraordinary dual role due to its nucleophilicity and reducing property with our single chemosensor, PND [4-(piperidin-1-yl) naphthalene-1,2-dione]. The initial nucleophilic attack via Michael addition (a lower concentration of H2S, blue fluorescence) is followed by the reduction of the 1,2-diketo functionality (a higher concentration of H2S, green fluorescence). This chemosensor, which also shows biological response, is remarkably effective in sensing the same analyte (H2S) at its different concentrations in a relay pathway via a fluorescence "off-on-on" mechanism, and this is also supported by DFT calculation and Cyclic voltammograms.


Assuntos
Fluorescência , Corantes Fluorescentes/química , Sulfeto de Hidrogênio/química , Naftalenos/química , Técnicas Eletroquímicas , Oxirredução , Teoria Quântica
5.
Org Biomol Chem ; 13(7): 2134-9, 2015 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-25530298

RESUMO

Our designed and synthesized chemosensor naphthalene based chromenyl derivative (NAC) [1-(3-hydroxy-3 methyl-3H-benzo[f]chromen-2-yl) ethanone] has been used for fast (<30 s, DL = 0.22 ppb) and selective detection of N2H4 by a new way via the chromenyl ring opening followed by the pyrazole ring formation giving a strong blue fluorescence. The DFT study and the real application in different water samples along with the dipstick method in low cost devices have also been performed here. Human lung cancer cells (NCI-H460) have been used for hydrazinolysis of the NAC in vivo system for detection by the appearance of blue fluorescence and also for the MTT assay showing its remarkable cancer sensitivity.


Assuntos
Cromonas/química , Hidrazinas/análise , Neoplasias Pulmonares/química , Naftóis/química , Teoria Quântica , Cromonas/síntese química , Humanos , Neoplasias Pulmonares/patologia , Estrutura Molecular , Espectrometria de Fluorescência
6.
Z Naturforsch C J Biosci ; 69(1-2): 81-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24772827

RESUMO

Base excision repair (BER) is a key pathway for maintaining genomic stability. A key enzyme in the BER pathway is DNA polymerase beta (polbeta). It has been shown that more than 11% of breast, bladder, esophageal, colon, and gastric cancer samples studied so far exhibit polbeta mutation. A truncated form of polbeta, polbetadelta (exon 11 deletion), identified in a colon tumour sample, exhibited dominant negative activity. Using this polbetadelta as bait, we screened a HeLa cDNA library for any interacting protein(s) in the yeast two-hybrid (Y2H) system. Polbetadelta was cloned into a pGBKT7 vector (pGBKT7-polbetadelta). pGBKT7-polbetadelta was transformed into the yeast strain AH109. Then the cDNA library was co-transformed into AH109/pGBKT7-polbetadelta and screened by the selection procedure. The yeast-purified plasmids were transformed into Escherichia coli. Plasmid DNA was isolated from the colonies, purified, digested with Sma I and Sal I, and the fragments were sequenced. Four positive clones were obtained. Out of these, three proteins were already known to interact with polbeta (XRCC1, MGC5306, and AP endonuclease 1). The only member previously not known to interact with polbeta was phosphatidylinositol glycosylase type S (PIGS). PIGS is a 64-kDa membrane protein, encoded in chromosome 17. The PIGS protein interacts also with wild-type polbeta which was confirmed by co-immunoprecipitation and Western blot analysis. The role of the newly identified protein in the dominant negative function of the variant form of polbeta remains to be seen.


Assuntos
DNA Polimerase beta/metabolismo , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Técnicas do Sistema de Duplo-Híbrido , Sequência de Bases , Primers do DNA , Humanos
7.
Analyst ; 138(16): 4593-8, 2013 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-23752275

RESUMO

A new "naked-eye" and ratiometric fluorescent zinc sensor (TAQ) of carboxamidoquinoline with 2-chloro-N-(quinol-8-yl)-acetamide as a receptor was designed and synthesized. The sensor shows good water solubility and high selectivity for sensing; about a 15-fold increase in fluorescence quantum yield and a 100 nm red-shift of fluorescence emission upon binding Zn²âº in aqueous HEPES buffer solution are observed. The human lung cancer cell line (A549) activity is also demonstrated.


Assuntos
Técnicas Biossensoriais/métodos , Morte Celular/fisiologia , Neoplasias Pulmonares/metabolismo , Água/metabolismo , Zinco/metabolismo , Linhagem Celular Tumoral , Corantes Fluorescentes/química , Corantes Fluorescentes/metabolismo , Humanos , Solubilidade , Espectrometria de Fluorescência/métodos , Água/química , Zinco/química
8.
ACS Omega ; 8(1): 636-647, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36643564

RESUMO

A new quercetin-based iron(III) cationic complex [Fe(Qr)Cl(H2O)(MeO)] (complex 1) is created in the current study by condensation of quercetin with ferric chloride in the presence of Et3N. Comprehensive spectroscopic analysis and conductometric measurement are used to pinpoint complex 1. The generated complex's +3-oxidation state has been verified by electron paramagnetic resonance (EPR) research. Density functional theory analysis was used to structurally optimize the structure of complex 1. Before biomedical use, a variety of biophysical studies are implemented to evaluate the binding capacity of complex 1 with DNA and human serum albumin (HSA) protein. The findings of the electronic titration between complex 1 and DNA, as well as the stunning fall in the fluorescence intensities of the HSA and EtBr-DNA/DAPI-DNA domain after complex 1 is gradually added, give us confidence that complex 1 has a strong affinity for both macromolecules. It is interesting to note that the displacement experiment confirms partial intercalation as well as the groove binding mechanism of the title complex with DNA. The time-dependent fluorescence analysis indicates that after interaction with complex 1, HSA will exhibit static quenching. The thermodynamic parameter values in the HSA-complex 1 interaction provide evidence for the hydrophobicity-induced pathway leading to spontaneous protein-complex 1 interaction. The two macromolecules' configurations are verified to be preserved when they are associated with complex 1, and this is done via circular dichroism spectral titration. The molecular docking investigation, which is a theoretical experiment, provides complete support for the experimental findings. The potential of the investigated complex to be an anticancer drug has been examined by employing the MTT assay technique, which is carried out on HeLa cancer cell lines and HEK-293 normal cell lines. The MTT assay results validate the ability of complex 1 to display significant anticancer properties. Finally, by using the AO/PI staining approach, the apoptotic-induced cell-killing mechanism as well as the detection of cell morphological changes has been confirmed.

9.
Heliyon ; 9(12): e22712, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38125469

RESUMO

In the current study, one new quercetin-based Zn(II) complex [Zn(Qr)(CNNCN)(H2O)2] (Complex 1) which is developed by condensation of quercetin with ZnCl2 in the presence of NaN(CN)2 and Cu(II) complex [Cu(Qr)N3(CH3OH)(H2O)] (complex 2) which is developed by the condensation reaction of quercetin and CuCl2 in presence of NaN3, are thoroughly examined in relation to their use in biomedicine. The results of several spectroscopic studied confirm the structure of both the complexes and the Density Functional Theory (DFT) study helps to optimize the structure of complex 1 and 2. After completion of the identification process, DNA and Human Serum Albumin (HSA) binding efficacy of both the investigated complexes are performed by implementing a long range of biophysical studies and a thorough analysis of the results unveils that complex 1 has better interaction efficacy with the macromolecules than complex 2. The binding efficacy of complex 1 is comparatively higher towards both macromolecules because of its pure groove binding mode during interaction with DNA and the presence of an extra H-bond during connection with HSA. The experimental host-guest binding results is fully validated by molecular docking study. Interestingly complex 1 shows better antioxidant properties than complex 2, as well as quercetin, and it has strong anticancer property with minimal damage to normal cells, which is proved by the MTT assay study. Better DNA and HSA binding efficacy of 1 may be the reason for the better anticancer property of complex 1.

10.
Radiat Oncol J ; 40(1): 66-78, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35368202

RESUMO

PURPOSE: DNA polymerase ß (Polß) acts in the base excision repair (BER) pathway. Mutations in DNA polymerase ß (Polß) are associated with different cancers. A variant of Polß with a 97 amino acid deletion (PolßΔ), in heterozygous conditions with wild-type Polß, was identified in sporadic ovarian tumor samples. This study aims to evaluate the gamma radiation sensitivity of PolßΔ for possible target therapy in ovarian cancer treatment. MATERIALS AND METHODS: PolßΔ cDNA was cloned in a GFP vector and transfected in PA1 cells. Stable cells (PA1PolßΔ) were treated with 60Co sourced gamma-ray (0-15 Gy) to investigate their radiation sensitivity. The affinity of PolßΔ with DNA evaluated by DNA protein in silico docking experiments. RESULTS: The result showed a statistically significant (p < 0.05) higher sensitivity towards radiation at different doses (0-15 Gy) and time-point (48-72 hours) for PA1PolßΔ cells in comparison with normal PA1 cells. Ten Gy of gamma radiation was found to be the optimal dose. Significantly more PA1PolßΔ cells were killed at this dose than PA1 cells after 48 hours of treatment via an apoptotic pathway. The in silico docking experiments revealed that PolßΔ has more substantial binding potential towards the dsDNA than wild-type Polß, suggesting a possible failure of BER pathway that results in cell death. CONCLUSION: Our study showed that the PA1PolßΔ cells were more susceptible than PA1 cells to gamma radiation. In the future, the potentiality of ionizing radiation to treat this type of cancer will be checked in animal models.

11.
Anal Methods ; 14(28): 2739-2744, 2022 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-35775440

RESUMO

Fluorescein coupled with 3-(aminomethyl)-4,6-dimethylpyridin-2(1H)-one (FAD) was synthesized for the selective recognition of Zn2+ over other interfering metal ions in acetonitrile/aqueous buffer (1 : 1). Interestingly, there was a significant fluorescence enhancement of FAD in association with Zn2+ at 426 nm by strong chelation-induced fluorescence enhancement (CHEF) without interrupting the cyclic spirolactam ring. A binding stoichiometric ratio of 1 : 2 for the ligand FAD with metal Zn2+ was proven by a Jobs plot. However, the cyclic spirolactam ring was opened by hypochlorite (OCl-) as well as oxidative cleavage of the imine bond, which resulted in the emission enhancement of the wavelength at 520 nm. The binding constant and detection limit of FAD towards Zn2+ were determined to be 1 × 104 M-1 and 1.79 µM, respectively, and the detection limit for OCl- was determined as 2.24 µM. We introduced here a dual-mode chemosensor FAD having both the reactive functionalities for the simultaneous detection of Zn2+ and OCl- by employing a metal coordination (Zn2+) and analytes (OCl-) induced chemodosimetric approach, respectively. Furthermore, for the practical application, we studied the fluorescence imaging inside HeLa cells by using FAD, which demonstrated it can be very useful as a selective and sensitive fluorescent probe for zinc.


Assuntos
Ácido Hipocloroso , Zinco , Flavina-Adenina Dinucleotídeo , Fluoresceína , Células HeLa , Humanos , Espectrometria de Fluorescência , Zinco/química
12.
ACS Omega ; 7(27): 23276-23288, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35847281

RESUMO

A new versatile azide-bridged polymeric Cu(II) complex, namely, [Cu(L)(µ1,3-N3)]∞ (1), was synthesized utilizing an N,N,O-donor piperidine-based Schiff base ligand (E)-4-bromo-2-((2-(-1-yl)imino)methyl)phenol (HL), obtained via the condensation reaction of 1-(2-aminoethyl) piperidine and 5-bromo salicylaldehyde. The single-crystal X-ray diffraction analysis reveals that complex 1 consists of an end-to-end azido-bridged polymeric network, which is further rationalized with the help of a density functional theory (DFT) study. After routine characterization with a range of physicochemical studies, complex 1 is exploited to evaluate its biomedical potential. Initially, theoretical inspection with the help of a molecular docking study indicated the ability of complex 1 to effectively bind with macromolecules such as DNA and the human serum albumin (HSA) protein. The theoretical aspect was further verified by adopting several spectroscopic techniques. The electronic absorption spectroscopic analysis indicates a remarkable binding efficiency of Complex 1 with both DNA and HSA. The notable fluorescence intensity reduction of the ethidium bromide (EtBr)-DNA adduct, 4',6-diamidino-2-phenylindole (DAPI)-DNA adduct, and HSA after the gradual addition of complex 1 authenticates its promising binding potential with the macromolecules. The retention of the canonical B form of DNA and α form of HSA during the association of complex 1 was confirmed by implementing a circular dichroism spectral study. The association ability of complex 1 with macromolecules further inspired us to inspect its impact on different cell lines such as HeLa (cervical cancer cell), PA1 (ovarian cancer cell), and HEK (normal cell). The dose-dependent and time-dependent in vitro 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay suggests an effective antiproliferative property of complex 1 with low toxicity toward the normal cell line. Finally, the anticancer activity of complex 1 toward carcinoma cell lines was analyzed by nuclear and cellular staining techniques, unveiling the cell death mechanism.

13.
Int J Biol Macromol ; 168: 537-549, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33316341

RESUMO

This study aimed to investigate the molecular characterization, antioxidant activity in vitro, cytotoxicity study of an exopolysaccharide isolated from Citrobacter freundii. Firstly, the culture conditions were standardized by the Design of experiments (DoE) based approach, and the final yield of thecrude exopolysaccharide was optimized at 2568 ± 169 mg L-1. One large fraction of exopolysaccharide was obtained from the culture filtrate by size exclusion chromatography and molecular characteristics were studied. A new mannose rich exopolysaccharide (Fraction-I) with average molecular weight ~ 1.34 × 105 Da was isolated. The sugar analysis showed the presence of mannose and glucose in a molar ratio of nearly 7:2 respectively. The structure of the repeating unit in the exopolysaccharide was determined through chemical and 1D/2D- NMR experiments as: Finally, the antioxidant activity, and the cytotoxicity of the exopolysaccharide were investigated and the relationship with molecular properties was discussed as well.


Assuntos
Antineoplásicos/química , Antioxidantes/química , Citrobacter freundii/crescimento & desenvolvimento , Polissacarídeos Bacterianos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Sequência de Carboidratos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia em Gel , Citrobacter freundii/química , Células HeLa , Humanos , Hidrólise , Espectroscopia de Ressonância Magnética , Peso Molecular , Polissacarídeos Bacterianos/isolamento & purificação , Polissacarídeos Bacterianos/farmacologia
14.
Int J Biol Macromol ; 162: 1025-1034, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32599238

RESUMO

A green synthesis of silver nanoparticles was synthesized by AgNO3 with arabinoxylan, isolated from green stem of Andrographis paniculata (Kalmegh). The synthesized Ag NPs-arabinoxylan conjugates were characterized by UV-vis spectroscopy, FE-SEM, TEM, XRD, TGA, EDX, and Zeta potential experiments. The Ag NPs formation was established by the surface plasmon resonance band ~410.25 nm. SEM image showed mostly spherical morphology of Ag NPs. The fcc crystalline nature was identified by XRD, SAED and the size were 24.5 and 25 nm from TEM and XRD analysis respectively. The prepared Ag NPs showed dose-dependent antimicrobial activity against Streptococcus pneumonia, Candida albicans and E. coli. The nanoparciles damage 4% hemolysis to human RBCs at 12.5 µg/mL. MTT assay of Ag NPs showed that half of the cell killed at 10 µg/mL and wound healing assay observed effective inhibition cell proliferation.


Assuntos
Acanthaceae/química , Anti-Infecciosos , Candida albicans/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Nanopartículas Metálicas/química , Streptococcus pneumoniae/crescimento & desenvolvimento , Xilanos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Química Verde , Prata/química , Prata/farmacologia , Xilanos/isolamento & purificação
15.
Carbohydr Polym ; 222: 114990, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320072

RESUMO

A water insoluble ß-glucan (PS), with molecular mass ∼9.16 × 104 Da was isolated from the 4% alkaline extract of an edible mushroom, Pleurotus djamor and found to consist of (1→3)-ß-d-glucopyranosyl moiety. The structure of the PS was elucidated on the basis of total hydrolysis, methylation analysis, periodate oxidation, and NMR experiments (1H, 13C, DQF-COSY, DEPT-135, and HSQC). The structure of the repeating unit of the polysaccharide was established as: →3)-ß-d-Glcp-(1→. The water insoluble ß-glucan showed cytotoxic effect against PA1 cells, where˜50% population was destroyed at 100 µg/mL concentration, and almost all cells at 250 µg/mL concentration. The wound healing assay showed significant anticarcinogenic effect against ovarian carcinoma PA1 cells after 48 h of treatment.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Pleurotus/metabolismo , beta-Glucanas , Sequência de Carboidratos , Feminino , Humanos , Solubilidade , Células Tumorais Cultivadas , beta-Glucanas/química , beta-Glucanas/farmacologia
16.
Iran Biomed J ; 22(5): 355-9, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29524322

RESUMO

Background: DNA polymerase ß (pol ß) is a key enzyme of base excision repair pathway. It is a 1-kb gene consisting of 14 exons. Its catalytic part lies between exon 8 and exon 14. Exon 12 has a role in deoxyribonucleotide triphosphate selection for nucleotide transferase activity. Methods: Genomic DNA was isolated from ovarian carcinoma samples. Single strand conformation polymorphism method was used to detect mutation in genomic DNA. Results: Twenty-four patients of the 152 pair of tumor samples (15.8%) exhibited a point mutation (C→G) in position 725 in exon 12, which shifts proline to arginine (P242R). Statistical analysis showed a significant (p < 0.001) relationship between pol ß mutation and the age of detection. Conclusion: This is a newly reported somatic mutation of pol ß in ovarian carcinoma patients from India.


Assuntos
DNA Polimerase beta/genética , Éxons/genética , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética , Mutação Puntual/genética , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade
17.
Cancer Res ; 64(21): 7673-7, 2004 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-15520167

RESUMO

A novel protein MGC5306 has been identified in yeast-two-hybrid analysis by screening a HeLa cDNA library with a truncated DNA polymerasebeta (polbetaDelta) as bait. The polbetaDelta is expressed in various types of cancers. Co-immunoprecipitation-Western blot analysis confirms not only its interaction with polbetaDelta but also with wild-type polbeta. Binding to polbeta indicates potential function of MGC5306 in repair pathway. Transfection of cells with MGC5306-GFP and Western blot analysis with anti-MGC5306 antibody reveal its nuclear localization. MGC5306 is expressed in human carcinomas and tumor cell lines but not in normal tissues, suggesting MGC5306 is most likely involved in carcinogenesis. An antigrowth activity and modulations of cell cycle events are identified in cells expressing siRNAMGC5306.


Assuntos
DNA Polimerase beta/metabolismo , Proteínas Nucleares/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Ciclo Celular , Sobrevivência Celular , Feminino , Células HeLa , Humanos , Dados de Sequência Molecular , Neoplasias Ovarianas/química , Fenótipo , RNA Interferente Pequeno/farmacologia , Técnicas do Sistema de Duplo-Híbrido
18.
Asian Pac J Cancer Prev ; 16(18): 8177-86, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26745057

RESUMO

The present study was aimed at determining the effects of alkylating and oxidative stress inducing agents on a newly identified variant of DNA polymerase beta (polß Δ208-304) specific for ovarian cancer. Pol ß Δ208-304 has a deletion of exons 11-13 which lie in the catalytic part of enzyme. We compared the effect of these chemicals on HeLa cells and HeLa cells stably transfected with this variant cloned into in pcDNAI/neo vector by MTT, colony forming and apoptosis assays. Polß Δ208-304 cells exhibited greater sensitivity to an alkylating agent and less sensitivity towards H2O2 and UV when compared with HeLa cells alone. It has been shown that cell death in Pol ß Δ208-304 transfected HeLa cells is mediated by the caspase 9 cascade. Exon 11 has nucleotidyl selection activity, while exons 12 and 13 have dNTP selection activity. Hence deletion of this part may affect polymerizing activity although single strand binding and double strand binding activity may remain same. The lack of this part may adversely affect catalytic activity of DNA polymerase beta so that the variant may act as a dominant negative mutant. This would represent clinical significance if translated into a clinical setting because resistance to radiation or chemotherapy during the relapse of the disease could be potentially overcome by this approach.


Assuntos
Alquilantes/farmacologia , DNA Polimerase beta/metabolismo , Éxons/genética , Peróxido de Hidrogênio/farmacologia , Neoplasias Ovarianas/patologia , Estresse Oxidativo/efeitos dos fármacos , Deleção de Sequência , Apoptose/efeitos dos fármacos , Western Blotting , Caspases/genética , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , DNA Polimerase beta/genética , Feminino , Células HeLa , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/enzimologia , Oxidantes/farmacologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas , Raios Ultravioleta
19.
Gene Expr ; 10(3): 115-23, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12064574

RESUMO

The 39-kDa DNA polymerase beta (pol beta) is an essential enzyme in short-patch base excision repair pathway. A wild-type and a truncated forms of pol beta proteins are expressed in primary colorectal and breast adenocarcinomas and in a primary culture of renal cell carcinoma. To test whether pol beta has a contributory role in tumorigenicity of human tumor cell lines, we have undertaken a study to determine expression of pol beta in colon, breast, and prostate tumor cell lines. Unlike primary colon tumor cells, three types of pol beta mRNA have been identified in HCT116, LoVo, and DLD1, colon tumor cell lines. A 111-bp-deleted pol beta transcript was expressed in MCF7, a breast tumor cell line, but not in primary breast tumor cells. An expression of a smaller pol beta transcript has been revealed in DU145, a prostate tumor cell line, whereas, a single base (T) deletion in mRNA at codon 191 was found in prostate cancer tissue. Interestingly, a wild-type pol beta transcript was also expressed in all tumor cell lines similar to primary tumor cells. Furthermore, the cell extract of LoVo exhibited highest gap-filling synthesis function of pol beta when the extract of DU145 showed lowest activity. MNNG, a DNA alkylating agent, enhanced the gap-filling synthesis activity in extracts of LoVo cell line. Furthermore, the cellular viability of LoVo and HCT116 cells is sensitive to MNNG when DU145 cells are resistant. These results demonstrate heterogeneity in pol beta mRNA expression, which may be a risk factor related to tumorigenic activities of tumor cell lines.


Assuntos
DNA Polimerase beta/genética , Reparo do DNA , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , DNA Polimerase beta/metabolismo , DNA de Neoplasias/metabolismo , Feminino , Expressão Gênica , Humanos , Masculino , Metilnitronitrosoguanidina/farmacologia , Neoplasias/enzimologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Células Tumorais Cultivadas , Ensaio Tumoral de Célula-Tronco
20.
Oncol Rep ; 11(1): 231-6, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14654931

RESUMO

DNA from 45 primary prostate tumors and corresponding normal tissues were analyzed to detect whether the alterations of transforming growth factor beta receptor II (TGFbetaRII) and insulin growth factor receptor II (IGFRII) are associated with microsatellite instability (MSI). We identified that 25 tumors were microsatellite unstable (55%). The remaining 20 tumors are found to be microsatellite stable. Loss of heterozygosity (LOH) was also tested at various loci. Results indicate that in case of TGFbetaRII, the rate of frame-shift mutation depends on the number of polyadenine [poly(A)] tracts. Twelve percent of the tumors had frame-shift alteration at BAT-RII locus which has 10 poly(A) repeats. Twenty percent of the tumors had frame-shift at BAT-25 locus which has 25 poly(A) repeats. In addition, IGFRII gene was examined for the presence of mutation in the repetitive sequences. Seven of the 25 tumors showed deletion of a G within eight poly(G) repeats. Besides these changes there were two tumors which showed a novel insertion of A within this poly(G) repeat making a change in 9 samples (R4, 36%). On the other hand, 4 tumors showed changes within the 5CT repeats. In addition, 3 tumors showed another novel insertion of C within the CT repeats.


Assuntos
Repetições de Microssatélites/genética , Neoplasias da Próstata/patologia , Receptor IGF Tipo 2/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Sequência de Bases , Análise Mutacional de DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , Humanos , Perda de Heterozigosidade , Masculino , Mutagênese Insercional , Reação em Cadeia da Polimerase , Neoplasias da Próstata/genética , Proteínas Serina-Treonina Quinases , Receptor do Fator de Crescimento Transformador beta Tipo II , Deleção de Sequência
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