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1.
Mol Cancer ; 22(1): 146, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667354

RESUMO

Multidrug resistance renders treatment failure in a large proportion of head and neck squamous cell carcinoma (HNSCC) patients that require multimodal therapy involving chemotherapy in conjunction with surgery and/or radiotherapy. Molecular events conferring chemoresistance remain unclear. Through transcriptome datamining, 28 genes were subjected to pharmacological and siRNA rescue functional assays on 12 strains of chemoresistant cell lines each against cisplatin, 5-fluorouracil (5FU), paclitaxel (PTX) and docetaxel (DTX). Ten multidrug chemoresistance genes (TOP2A, DNMT1, INHBA, CXCL8, NEK2, FOXO6, VIM, FOXM1B, NR3C1 and BIRC5) were identified. Of these, four genes (TOP2A, DNMT1, INHBA and NEK2) were upregulated in an HNSCC patient cohort (n = 221). Silencing NEK2 abrogated chemoresistance in all drug-resistant cell strains. INHBA and TOP2A were found to confer chemoresistance in majority of the drug-resistant cell strains whereas DNMT1 showed heterogeneous results. Pan-cancer Kaplan-Meier survival analysis on 21 human cancer types revealed significant prognostic values for INHBA and NEK2 in at least 16 cancer types. Drug library screens identified two compounds (Sirodesmin A and Carfilzomib) targeting both INHBA and NEK2 and re-sensitised cisplatin-resistant cells. We have provided the first evidence for NEK2 and INHBA in conferring chemoresistance in HNSCC cells and siRNA gene silencing of either gene abrogated multidrug chemoresistance. The two existing compounds could be repurposed to counteract cisplatin chemoresistance in HNSCC. This finding may lead to novel personalised biomarker-linked therapeutics that can prevent and/or abrogate chemoresistance in HNSCC and other tumour types with elevated NEK2 and INHBA expression. Further investigation is necessary to delineate their signalling mechanisms in tumour chemoresistance.


Assuntos
Cisplatino , Neoplasias de Cabeça e Pescoço , Humanos , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Cisplatino/farmacologia , Transdução de Sinais , Linhagem Celular , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Fatores de Transcrição Forkhead , Quinases Relacionadas a NIMA/genética
2.
J Mol Recognit ; 36(7): e3021, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37092713

RESUMO

Visceral leishmaniasis (VL) is caused by Leishmania donovani (Ld), and most cases occur in Brazil, East Africa, and India. The treatment for VL is limited and has many adverse effects. The development of safer and more efficacious drugs is urgently needed. Drug repurposing is one of the best processes to repurpose existing drugs. Ornithine decarboxylase (ODC) is an important target against L. donovani in the polyamine biosynthesis pathway. In this study, we have modeled the 3D structure of ODC and performed high-throughput virtual screening of 8630 ZINC database ligands against Leishmania donovani ornithine decarboxylase (Ld ODC), selecting 45 ligands based on their high binding score. It is further validated through molecular docking simulation and the selection of the top two lead molecules (ceftaroline fosamil and rimegepant) for Molecular Dynamics (MD) simulation, Density functional theory (DFT), and molecular mechanics generalized born surface area (MMGBSA) analysis. The results showed that the binding affinities of ceftaroline fosamil, and rimegepant are, respectively, -10.719 and 10.159 kcal/mol. The docking complexes of the two lead compounds, ceftaroline fosamil, and rimegepant, with the target ODC, were found stable during molecular dynamics simulations. Furthermore, the analysis of MMGBSA revealed that these compounds had a high binding free energy. The DFT analysis showed that the top lead molecules were more reactive than the standard drug (pentamidine). In-silico findings demonstrated that ceftaroline fosamil, and rimegepant might be recognized as potent antagonists against ODC for the treatment of VL.


Assuntos
Leishmania donovani , Leishmaniose Visceral , Humanos , Inibidores da Ornitina Descarboxilase/química , Inibidores da Ornitina Descarboxilase/farmacologia , Reposicionamento de Medicamentos , Simulação de Acoplamento Molecular , Ornitina Descarboxilase/química , Ornitina Descarboxilase/metabolismo , Ornitina Descarboxilase/farmacologia , Ligantes , Leishmania donovani/metabolismo , Ceftarolina
3.
PLoS Genet ; 16(4): e1008721, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32339198

RESUMO

Current estimates suggest 50% of glaucoma blindness worldwide is caused by primary angle-closure glaucoma (PACG) but the causative gene is not known. We used genetic linkage and whole genome sequencing to identify Spermatogenesis Associated Protein 13, SPATA13 (NM_001166271; NP_001159743, SPATA13 isoform I), also known as ASEF2 (Adenomatous polyposis coli-stimulated guanine nucleotide exchange factor 2), as the causal gene for PACG in a large seven-generation white British family showing variable expression and incomplete penetrance. The 9 bp deletion, c.1432_1440del; p.478_480del was present in all affected individuals with angle-closure disease. We show ubiquitous expression of this transcript in cell lines derived from human tissues and in iris, retina, retinal pigment and ciliary epithelia, cornea and lens. We also identified eight additional mutations in SPATA13 in a cohort of 189 unrelated PACS/PAC/PACG samples. This gene encodes a 1277 residue protein which localises to the nucleus with partial co-localisation with nuclear speckles. In cells undergoing mitosis SPATA13 isoform I becomes part of the kinetochore complex co-localising with two kinetochore markers, polo like kinase 1 (PLK-1) and centrosome-associated protein E (CENP-E). The 9 bp deletion reported in this study increases the RAC1-dependent guanine nucleotide exchange factors (GEF) activity. The increase in GEF activity was also observed in three other variants identified in this study. Taken together, our data suggest that SPATA13 is involved in the regulation of mitosis and the mutations dysregulate GEF activity affecting homeostasis in tissues where it is highly expressed, influencing PACG pathogenesis.


Assuntos
Glaucoma de Ângulo Aberto/genética , Fatores de Troca do Nucleotídeo Guanina/genética , Mutação , Adolescente , Adulto , Idoso , Divisão Celular , Núcleo Celular/metabolismo , Olho/metabolismo , Feminino , Glaucoma de Ângulo Aberto/patologia , Fatores de Troca do Nucleotídeo Guanina/química , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Humanos , Cinetocoros/metabolismo , Masculino , Pessoa de Meia-Idade , Linhagem , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Transporte Proteico
4.
Molecules ; 28(15)2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37570823

RESUMO

Polo-like kinase-1 (PLK-1) is an essential mitotic serine/threonine (Ser/Thr) kinase that belongs to the Polo-like kinase (PLK) family and is overexpressed in non-small cell lung cancer (NSCLC) via promotion of cell division. Therefore, PLK-1 may act as a promising target for the therapeutic cure of various cancers. Although a variety of anti-cancer drugs, both synthetic and naturally occurring, such as volasertib, onvansertib, thymoquinone, and quercetin, are available either alone or in combination with other therapies, they have limited efficacy, especially in the advanced stages of cancer. To the best of our knowledge, no anticancer agent has been reported from marine algae or microorganisms to date. Thus, the aim of the present study is a high-throughput virtual screening of phlorotannins, obtained from edible brown algae, using molecular docking and molecular dynamic simulation analysis. Among these, Pentafuhalol-B (PtB) showed the lowest binding energy (best of triplicate runs) against the target protein PLK-1 as compared to the reference drug volasertib. Further, in MD simulation (best of triplicate runs), the PtB-PLK-1 complex displayed stability in an implicit water system through the formation of strong molecular interactions. Additionally, MMGBSA calculation (best of triplicate runs) was also performed to validate the PtB-PLK-1 complex binding affinities and stability. Moreover, the chemical reactivity of PtB towards the PLK-1 target was also optimised using density functional theory (DFT) calculations, which exhibited a lower HOMO-LUMO energy gap. Overall, these studies suggest that PtB binds strongly within the pocket sites of PLK-1 through the formation of a stable complex, and also shows higher chemical reactivity than the reference drug volasertib. The present study demonstrated the inhibitory nature of PtB against the PLK-1 protein, establishing its potential usefulness as a small molecule inhibitor for the treatment of different types of cancer.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Simulação de Acoplamento Molecular , Proteínas de Ciclo Celular/metabolismo , Divisão Celular , Antineoplásicos/farmacologia , Antineoplásicos/química
5.
Int J Mol Sci ; 23(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35683030

RESUMO

Vimentin, a type III intermediate filament protein, is found in most cells along with microfilaments and microtubules. It has been shown that the head domain folds back to associate with the rod domain and this association is essential for filament assembly. The N-terminally tagged vimentin has been widely used to label the cytoskeleton in live cell imaging. Although there is previous evidence that EGFP tagged vimentin fails to form filaments but is able to integrate into a pre-existing network, no study has systematically investigated or established a molecular basis for this observation. To determine whether a tag would affect de novo filament assembly, we used vimentin fused at the N-terminus with two different sized tags, AcGFP (239 residues, 27 kDa) and 3 × FLAG (22 residues; 2.4 kDa) to assemble into filaments in two vimentin-deficient epithelial cells, MCF-7 and A431. We showed that regardless of tag size, N-terminally tagged vimentin aggregated into globules with a significant proportion co-aligning with ß-catenin at cell-cell junctions. However, the tagged vimentin aggregates could form filaments upon adding untagged vimentin at a ratio of 1:1 or when introduced into cells containing pre-existing filaments. The resultant filament network containing a mixture of tagged and untagged vimentin was less stable compared to that formed by only untagged vimentin. The data suggest that placing a tag at the N-terminus may create steric hinderance in case of a large tag (AcGFP) or electrostatic repulsion in case of highly charged tag (3 × FLAG) perhaps inducing a conformational change, which deleteriously affects the association between head and rod domains. Taken together our results shows that a free N-terminus is essential for filament assembly as N-terminally tagged vimentin is not only incapable of forming filaments, but it also destabilises when integrated into a pre-existing network.


Assuntos
Citoesqueleto , Filamentos Intermediários , Sequência de Aminoácidos , Citoesqueleto/metabolismo , Filamentos Intermediários/metabolismo , Transfecção , Vimentina/metabolismo
6.
BMC Cancer ; 19(1): 830, 2019 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-31443700

RESUMO

BACKGROUND: The concept of head and neck cancers (HNSCC) having unique molecular signatures is well accepted but relating this to clinical presentation and disease behaviour is essential for patient benefit. Currently the clinical significance of HNSCC molecular subtypes is uncertain therefore personalisation of HNSCC treatment is not yet possible. METHODS: We performed meta-analysis on 8 microarray studies and identified six significantly up- (PLAU, FN1, CDCA5) and down-regulated (CRNN, CLEC3B and DUOX1) genes which were subsequently quantified by RT-qPCR in 100 HNSCC patient margin and core tumour samples. RESULTS: Retrospective correlation with sociodemographic and clinicopathological patient details identified two subgroups of opposing molecular signature (+q6 and -q6) that correlated to two recognised high-risk HNSCC populations in the UK. The +q6 group were older, male, and excessive alcohol users whilst the -q6 group were younger, female, paan-chewers and predominantly Bangladeshi. Additionally, all patients with tumour recurrence were in the latter subgroup. CONCLUSIONS: We provide the first evidence linking distinct molecular signatures in HNSCC with clinical presentations. Prospective trials are required to determine the correlation between these distinct genotypes and disease progression or treatment response. This is an important step towards the ultimate goal of improving outcomes by utilising personalised molecular-signature-guided treatments for HNSCC patients.


Assuntos
Carcinoma de Células Escamosas de Cabeça e Pescoço/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Biomarcadores Tumorais , Biologia Computacional/métodos , Mineração de Dados , Suscetibilidade a Doenças , Feminino , Perfilação da Expressão Gênica , Predisposição Genética para Doença , Humanos , Estimativa de Kaplan-Meier , Masculino , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Seleção Genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Transcriptoma
7.
Cell Mol Biol (Noisy-le-grand) ; 65(7): 38-45, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31880516

RESUMO

The present study was accomplished to examine and compare the effect of specific antioxidant-rich oils on hyperglycemia, dyslipidemia, renal function markers and oxidative renal damage in diabetic rats for four weeks. Papaya (P), olive (O), fenugreek (Fe), bitter gourd (B) and fish (Fi) oils were used for this purpose. Streptozotocin (STZ) was injected intraperitoneally in a single dose to induce diabetes. All oils were given orally at a dose of 3g/kg for four weeks in respective group after induction of diabetes. After treatment with oils, blood was collected, and their kidneys were stored. The level of fasting blood glucose (FBG), glycated hemoglobin (HbA1c), total cholesterol (TC), triglycerides (TG), low-density lipoprotein-cholesterol (LDL-C) and very low-density lipoprotein-cholesterol (VLDL-C) increased while amylase and high-density lipoprotein cholesterol (HDL-C) level decreased in the diabetic rats. These changes were augmented by fenugreek, bitter gourd and olive oils treatment. Diabetic rats showed elevated renal function markers in serum, including, serum creatinine (Scr), blood urea nitrogen (BUN) and alkaline phosphatase (ALP), which were restrained significantly by fenugreek and bitter gourd oil treatment. Moreover, fenugreek and bitter gourd oils treatment significantly modulated the level of thiobarbituric reactive substances (TBARS), malonaldehyde (MDA) and catalase (CAT) in the kidney of diabetic rats. The histopathological examination also showed the protective effect of these oils. The study suggests that vegetable oils are effective in reducing hyperglycemia, dyslipidemia and renal damage related to the side effects of diabetes. Thus they may have therapeutic value for preventing diabetes side effects and may be included in oil diet treatment synergically. Thus, our data suggest that oils as potent antidiabetic agent and beneficial in the control of diabetes-related abnormalities such as hyperglycemia, dyslipidemia and renal damage of STZ induced rat model of type 2 diabetes. Our study also supports the suggestion that synergistic possibilities exist concerning the use of these oils in the treatment of diabetes mellitus.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Óleos de Peixe/uso terapêutico , Óleos de Plantas/uso terapêutico , Animais , Glicemia/efeitos dos fármacos , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Diabetes Mellitus Experimental/sangue , Dislipidemias/sangue , Dislipidemias/tratamento farmacológico , Hemoglobinas Glicadas/uso terapêutico , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Momordica charantia/química , Azeite de Oliva/uso terapêutico , Ratos , Ratos Wistar , Triglicerídeos/sangue , Trigonella/química
8.
Mol Cancer ; 17(1): 97, 2018 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-30008265

RESUMO

BACKGROUND: Exosomes are extracellular vesicles released by almost all cell types, including cancer cells, into bodily fluids such as saliva, plasma, breast milk, semen, urine, cerebrospinal fluid, amniotic fluid, synovial fluid and sputum. Their key function being intercellular communication with both neighbouring as well as distant cells. Cancer exosomes have been shown to regulate organ-specific metastasis. However, little is known about the functional differences and molecular consequences of normal cells responding to exosomes derived from normal cells compared to those derived from cancer cells. METHODS: Here, we characterised and compared the transcriptome profiles of primary human normal oral keratinocytes (HNOK) in response to exosomes isolated from either primary HNOK or head and neck squamous cell carcinoma (HNSCC) cell lines. RESULTS: In recipient HNOK cells, we found that regardless of normal or cancer derived, exosomes altered molecular programmes involved in matrix modulation (MMP9), cytoskeletal remodelling (TUBB6, FEZ1, CCT6A), viral/dsRNA-induced interferon (OAS1, IFI6), anti-inflammatory (TSC22D3), deubiquitin (OTUD1), lipid metabolism and membrane trafficking (BBOX1, LRP11, RAB6A). Interestingly, cancer exosomes, but not normal exosomes, modulated expression of matrix remodelling (EFEMP1, DDK3, SPARC), cell cycle (EEF2K), membrane remodelling (LAMP2, SRPX), differentiation (SPRR2E), apoptosis (CTSC), transcription/translation (KLF6, PUS7). We have also identified CEP55 as a potential cancer exosomal marker. CONCLUSIONS: In conclusion, both normal and cancer exosomes modulated unique gene expression pathways in normal recipient cells. Cancer cells may exploit exosomes to confer transcriptome reprogramming that leads to cancer-associated pathologies such as angiogenesis, immune evasion/modulation, cell fate alteration and metastasis. Molecular pathways and biomarkers identified in this study may be clinically exploitable for developing novel liquid-biopsy based diagnostics and immunotherapies.


Assuntos
Proteínas de Ciclo Celular/genética , Exossomos/genética , Perfilação da Expressão Gênica/métodos , Neoplasias de Cabeça e Pescoço/genética , Proteínas Nucleares/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Biomarcadores Tumorais/genética , Linhagem Celular Tumoral , Exossomos/patologia , Proteína Forkhead Box M1/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Queratinócitos/patologia , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
9.
Arch Toxicol ; 89(3): 289-317, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25618543

RESUMO

Apoptosis is a critically important biological process that plays an essential role in cell fate and homeostasis. An important component of the apoptotic pathway is the family of proteins commonly known as the B cell lymphoma-2 (Bcl-2). The primary role of Bcl-2 family members is the regulation of apoptosis. Although the structure of Bcl-2 family of proteins was reported nearly 10 years ago, however, it still surprises us with its structural and functional complexity and diversity. A number of studies have demonstrated that Bcl-2 family influences many other cellular processes beyond apoptosis which are generally independent of the regulation of apoptosis, suggesting additional roles for Bcl-2. The disruption of the regulation of apoptosis is a causative event in many diseases. Since the Bcl-2 family of proteins is the key regulator of apoptosis, the abnormalities in its function have been implicated in many diseases including cancer, neurodegenerative disorders, ischemia and autoimmune diseases. In the past few years, our understanding of the mechanism of action of Bcl-2 family of proteins and its implications in various pathological conditions has enhanced significantly. The focus of this review is to summarize the current knowledge on the structure and function of Bcl-2 family of proteins in apoptotic cellular processes. A number of drugs have been developed in the past few years that target different Bcl-2 members. The role of Bcl-2 proteins in the pathogenesis of various diseases and their pharmacological significance as effective molecular therapeutic targets is also discussed.


Assuntos
Apoptose/fisiologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Animais , Apoptose/efeitos dos fármacos , Doenças Autoimunes/tratamento farmacológico , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Sítios de Ligação , Humanos , Ligantes , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Membranas Mitocondriais/metabolismo , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Doenças Neurodegenerativas/patologia , Preparações Farmacêuticas/química , Ligação Proteica , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Transcrição Gênica
10.
Toxicol Appl Pharmacol ; 279(1): 1-7, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24848621

RESUMO

Diabetic nepropathy (DN) is considered as the leading cause of end-stage renal disease (ESRD) worldwide, but the current available treatments are limited. Recent experimental evidences support the role of chronic microinflammation in the development of DN. Therefore, the tumor necrosis factor-alpha (TNF-α) pathway has emerged as a new therapeutic target for the treatment of DN. We investigated the nephroprotective effects of chrysin (5, 7-dihydroxyflavone) in a high fat diet/streptozotocin (HFD/STZ)-induced type 2 diabetic Wistar albino rat model. Chrysin is a potent anti-inflammatory compound that is abundantly found in plant extracts, honey and bee propolis. The treatment with chrysin for 16weeks post induction of diabetes significantly abrogated renal dysfunction and oxidative stress. Chrysin treatment considerably reduced renal TNF-α expression and inhibited the nuclear transcription factor-kappa B (NF-кB) activation. Furthermore, chrysin treatment improved renal pathology and suppressed transforming growth factor-beta (TGF-ß), fibronectin and collagen-IV protein expressions in renal tissues. Chrysin also significantly reduced the serum levels of pro-inflammatory cytokines, interleukin-1beta (IL-1ß) and IL-6. Moreover, there were no appreciable differences in fasting blood glucose and serum insulin levels between the chrysin treated groups compared to the HFD/STZ-treated group. Hence, our results suggest that chrysin prevents the development of DN in HFD/STZ-induced type 2 diabetic rats through anti-inflammatory effects in the kidney by specifically targeting the TNF-α pathway.


Assuntos
Anti-Inflamatórios/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/tratamento farmacológico , Flavonoides/uso terapêutico , Animais , Glicemia/metabolismo , Western Blotting , Citocinas/biossíntese , Diabetes Mellitus Experimental/complicações , Nefropatias Diabéticas/patologia , Insulina/sangue , Rim/patologia , Testes de Função Renal , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossíntese
11.
Tumour Biol ; 35(3): 1965-71, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24096584

RESUMO

Increased risk may be associated with exposure to genotoxic agents during breast development because the undifferentiated ductal elements of breast are more susceptible to the action of genotoxic early in life and thus an impairment in Cytochrome P 4501A1 (CYP1A1) may contribute to the development of breast cancer. Therefore, we carried out the population-based study in a total of 105 Indian female breast cancer cases with equal normal adjacent controls. A total of 20 samples (20/105, 19.04 %) showed final mutations in the exon 7 of the CYP1A1 gene where 5 cases harbored frame shift mutation (deletion of G nucleotide), and the remaining were missense mutation observed in 15 cases of breast cancer with significant association to histological grade (chi square -7.20, p = 0.02), tumor stage (chi square -6.36, p = 0.01), menopausal stage (chi square -9.76, p = 0.001), and ER status (chi square -4.22, p = 0.03). We further did protein expression analysis of CYP1A1 through immunohistochemistry where 66 cases showed down or no expression (+) (66/105, 62.85 %), 28 cases with moderate expression (++) (28/105, 26.66 %), and 11 cases with high expression (+++) (11/105, 10.47 %). Highly significant associations were observed between protein expression and clinico-pathological variables like Her 2 category (chi square = 31.73, p < 0.0001) and tumor stage (chi square = 10.27, p = 0.005). Importantly, mutation(s) of the type like deletion of A nucleotide and missense mutation (Gly > Val) exclusively showed low (+) or no expression for the CYP1A1 protein when studied in relation to each other. In summary, CYP1A1 may be associated with breast cancer and its down regulation may serve as an important tool in the field of biomarker study.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Citocromo P-450 CYP1A1/biossíntese , Citocromo P-450 CYP1A1/genética , Predisposição Genética para Doença/genética , Mutação , Sequência de Bases , Biomarcadores Tumorais/análise , Análise Mutacional de DNA , Regulação para Baixo , Feminino , Humanos , Imuno-Histoquímica , Índia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Análise Serial de Tecidos
12.
Methods Mol Biol ; 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38180689

RESUMO

Site-directed mutagenesis (SDM) is a technique that allows mutation of specific nucleotide(s) in a codon to study its functional implications in a protein. Commercial kits are available, which require high-performance liquid chromatography purified oligos for this purpose. These kits are expensive, and they are not very efficient, so one has to sequence several clones to get a desired one. We present here a simple method that requires only crude oligos, commercially available high-fidelity enzymes, and the success rate is close to 100%. In addition, up to 6 different mutations can be introduced in one reaction without causing any fortuitous change in the vector backbone. Using this strategy, we have introduced 32 S/T➔A substitutions in the N-terminus head and 13 changes in the C-terminus tail domain of vimentin.

13.
Methods Mol Biol ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38411888

RESUMO

Short hairpin RNA (shRNA) is a technique used to silence gene expression stably in various cells. There are however several reported problems. First, the cloning of oligos can lead to ligation of multiple copies; second, premature termination of sequencing reaction during confirmation of hairpin template; third, microdeletions/substitutions in hairpin during cloning; and fourth, off target effects. In this chapter, we have described a retrovirus transduction-based protocol that can be used on cells in culture without encountering any of the reported issues. We have used this protocol to clone shRNA templates for at least 10 different genes and confirmed them by dideoxy sequencing. The knockdown of 75-90% for two mRNA expressing genes, CDH5 and keratin KRT80, and a long non-coding RNA, XIST, is presented here.

14.
Nat Prod Res ; : 1-4, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38462728

RESUMO

Bioassay targeted phyto-investigation of dried green walnut husk of Ribes glaciale Wall. yielded one new compound as ß-D-glucopyrano (4'→3)-ß-D-glucopyranose (1) and four known compounds namely scoparone (2), apigenin (3), ß-sitosterol (4) and ß-sitosterol-D-glucoside (5). The structure of new compound was elucidated with the help of 1D, 2D and HRESIMS analysis. The antioxidant activity of extract, fractions and pure were evaluated using 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and ferric ion reducing antioxidant power (FRAP) assays that found in the following order: butanol fr. (BF) > chloroform fr. (CF) > ethylacetate fr. (EF) > Petroleum ether fr. (PF). To search for potent antioxidant agents in extract, the isolated compounds 1, 2, 3, 4 and 5 were docked on the enzyme human NADPH oxidase, lipoxygenase, cytochrome P450 and myeloperoxidase. The compound 1 was found a potent inhibitor of target enzyme revealing its high free radical scavenging potential.

15.
Int J Cancer ; 132(9): 2095-106, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23034676

RESUMO

Histopathological discordance with molecular phenotype of many human cancers poses clinically challenging tasks for accurate cancer diagnosis, which impacts on treatment strategy and patient outcome. Hence, an objective, accurate and quantitative method is needed. A quantitative Malignancy Index Diagnostic System (qMIDS) was developed based on 14 FOXM1 (isoform B)-associated genes implicated in the regulation of the cell cycle, differentiation, ageing, genomic stability, epigenetic and stem cell renewal, and two reference genes. Their mRNA expression levels were translated via a prospectively designed algorithm, into a metric scoring system. Subjects from UK and Norway (n = 299) provided 359 head and neck tissue specimens. Diagnostic test performance was assessed using detection rate (DR) and false-positive rate (FPR). The median qMIDS scores were 1.3, 2.9 and 6.7 in healthy tissue, dysplasia and head and neck squamous cell carcinomas (HNSCC), respectively (UK prospective dataset, p<0.001); 1.4, 2.3 and 7.6 in unaffected, oral lichen planus, or HNSCC, respectively (Norwegian retrospective dataset with up to 19 years survival data, p<0.001). At a qMIDS cut-off of 4.0, DR was 94% and FPR was 3.2% (Norwegian dataset); and DR was 91% and FPR was 1.3% (UK dataset). We further demonstrated the transferability of qMIDS for diagnosing premalignant human vulva (n = 58) and skin (n = 21) SCCs, illustrating its potential clinical use for other cancer types. This study provided evidence that qMIDS was able to quantitatively diagnose and objectively stratify cancer aggressiveness. With further validation, qMIDS could enable early HNSCC detection and guide appropriate treatment. Early treatment intervention can lead to long-term reduction in healthcare costs and improve patient outcome.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/diagnóstico , Fatores de Transcrição Forkhead/genética , Neoplasias de Cabeça e Pescoço/diagnóstico , Lesões Pré-Cancerosas/diagnóstico , Neoplasias Cutâneas/diagnóstico , Neoplasias Vulvares/diagnóstico , Algoritmos , Carcinoma de Células Escamosas/genética , Células Cultivadas , Diagnóstico Precoce , Feminino , Proteína Forkhead Box M1 , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Neoplasias de Cabeça e Pescoço/genética , Humanos , Queratinócitos/citologia , Queratinócitos/metabolismo , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Noruega , Lesões Pré-Cancerosas/genética , Prognóstico , Estudos Prospectivos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/genética , Neoplasias Vulvares/genética
16.
Cancer ; 119(24): 4249-58, 2013 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-24114764

RESUMO

BACKGROUND: Epigenetic reprogramming of the methylome has been implicated in all stages of cancer evolution. It is now well accepted that cancer cells exploit epigenetic reprogramming, a mechanism that regulates stem/progenitor cell renewal and differentiation, to promote cancer initiation and progression. The oncogene FOXM1 has been implicated in all major forms of human cancer. METHODS: We have recently shown that aberrant upregulation of FOXM1 orchestrated a DNA methylation signature that mimics the cancer methylome landscape, from which we have identified a number of FOXM1-induced epigenetic markers. Differential promoter methylation and gene expression in clinical specimens were measured using commercially available bisulfite conversion kits and absolute quantitative PCR, respectively. RESULTS: Here, we investigated 8 FOXM1-induced differentially methylated genes, SPCS1, FLNA, CHPF, GLT8D1, C6orf136, MGAT1, NDUFA10, and PAFAH1B3, using human head and neck tissue specimens donated by 2 geographically independent patient cohorts from Norway and the United Kingdom. Two genes (GLT8D1 and C6orf136) were found to be differentially expressed in head and neck squamous cell carcinomas (HNSCCs). Using methylation-specific quantitative PCR, we confirmed that the promoters of GLT8D1 and C6orf136 were hypo- and hypermethylated, respectively, in HNSCC tissues. CONCLUSIONS: Given that epigenetic change precedes gene expression, methylation status of candidate genes identified from this study may represent a signature of premalignancy, rendering them potentially useful predictive biomarkers for precancer screening and/or therapeutic targets for cancer prevention.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma de Células Escamosas/genética , Fatores de Transcrição Forkhead/genética , Neoplasias de Cabeça e Pescoço/genética , Metilação de DNA , Epigênese Genética , Feminino , Proteína Forkhead Box M1 , Regulação Neoplásica da Expressão Gênica , Glicosiltransferases/genética , Humanos , Masculino , Pessoa de Meia-Idade , Noruega , Regiões Promotoras Genéticas , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Reino Unido , Regulação para Cima
17.
Parasitology ; 140(3): 406-13, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23137860

RESUMO

Quinine (QN) and quinidine (QND) have been commonly used as effective and affordable antimalarials for over many years. Quinine primarily is used for severe malaria treatment. However, plasmodia resistance to these drugs and poor patient compliance limits their administration to the patients. The declining sensitivity of the parasite to the drugs can thus be dealt with by combining with a suitable partner drug. In the present study QN/QND was assessed in combination with clarithromycin (CLTR), an antibiotic of the macrolide family. In vitro interactions of these drugs with CLTR against Plasmodium falciparum (P. falciparum) have shown a synergistic response with mean sum fractional inhibitory concentrations (ΣFICs) of ≤1 (0.85 ± 0.11 for QN + CLTR and 0.64 ± 0.09 for QND + CLTR) for all the tested combination ratios. Analysis of this combination of QN/QND with CLTR in mouse model against Plasmodium yoelii nigeriensis multi-drug resistant (P. yoelii nigeriensis MDR) showed that a dose of 200 mg/kg/day for 4 days of QN or QND produces 100% curative effect with 200 mg/kg/day for 7 days and 150 mg/kg/day for 7 days CLTR respectively, while the same dose of individual drugs could produce only up to a maximum 20% cure. It is postulated that CLTR, a CYP3A4 inhibitor, might have caused reduced CYP3A4 activity leading to increased plasma level of the QN/QND to produce enhanced antimalarial activity. Further, parasite apicoplast disruption by CLTR synergies the antimalarial action of QN and QND.


Assuntos
Antimaláricos/metabolismo , Claritromicina/metabolismo , Malária/tratamento farmacológico , Plasmodium falciparum/efeitos dos fármacos , Plasmodium yoelii/efeitos dos fármacos , Quinidina/metabolismo , Quinina/metabolismo , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Claritromicina/farmacologia , Claritromicina/uso terapêutico , Interações Medicamentosas , Resistência a Medicamentos , Quimioterapia Combinada , Humanos , Malária/mortalidade , Malária/parasitologia , Masculino , Camundongos , Testes de Sensibilidade Parasitária , Quinidina/farmacologia , Quinidina/uso terapêutico , Quinina/farmacologia , Quinina/uso terapêutico
18.
Int J Mol Sci ; 14(10): 19385-98, 2013 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-24071939

RESUMO

Keratin 15 (K15) is type I keratin protein co-expressed with the K5/K14 pair present in the basal keratinocytes of all stratified epithelia. Although it is a minor component of the cytoskeleton with a variable expression pattern, nonetheless its expression has been reported as a stem cell marker in the bulge of hair follicles. Conversely, suprabasal expression of K15 has also been reported in both normal and diseased tissues, which is inconsistent with its role as a stem cell marker. Our recently published work has given evidence of the molecular pathways that seem to control the expression of K15 in undifferentiated and differentiated cells. In this article, we have critically reviewed the published work to establish the reliability of K15 as an epidermal stem cell marker.


Assuntos
Biomarcadores/metabolismo , Epiderme/metabolismo , Queratina-15/metabolismo , Células-Tronco/metabolismo , Animais , Humanos
19.
Diagnostics (Basel) ; 13(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36832260

RESUMO

Detecting brain disorders using deep learning methods has received much hype during the last few years. Increased depth leads to more computational efficiency, accuracy, and optimization and less loss. Epilepsy is one of the most common chronic neurological disorders characterized by repeated seizures. We have developed a deep learning model using Deep convolutional Autoencoder-Bidirectional Long Short Memory for Epileptic Seizure Detection (DCAE-ESD-Bi-LSTM) for automatic detection of seizures using EEG data. The significant feature of our model is that it has contributed to the accurate and optimized diagnosis of epilepsy in ideal and real-life situations. The results on the benchmark (CHB-MIT) dataset and the dataset collected by the authors show the relevance of the proposed approach over the baseline deep learning techniques by achieving an accuracy of 99.8%, classification accuracy of 99.7%, sensitivity of 99.8%, specificity and precision of 99.9% and F1 score of 99.6%. Our approach can contribute to the accurate and optimized detection of seizures while scaling the design rules and increasing performance without changing the network's depth.

20.
Biomedicines ; 11(7)2023 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-37509597

RESUMO

Alternative and modified therapeutic approaches are key elements in culminating antibiotic resistance. To this end, an experimental trial was conducted to determine the cytotoxicity and antibacterial potential of composites of magnesium oxide (MgO) nanoparticles and antibiotics stabilized in sodium alginate gel against multi-drug-resistant Staphylococcus aureus isolated from a houbara bustard. The characterization of preparations was carried out using X-ray diffraction (XRD), scanning transmissible electron microscopy (STEM), and Fourier-transform infrared spectroscopy (FTIR). The preparations used in this trial consisted of gel-stabilized MgO nanoparticles (MG), gel-stabilized tylosin (GT), gel-stabilized ampicillin (GA), gel-stabilized cefoxitin (GC), gel-stabilized MgO and tylosin (GMT), gel-stabilized MgO and cefoxitin (GMC), and gel-stabilized MgO and ampicillin (GMA). The study presents composites that cause a lesser extent of damage to DNA while significantly enhancing mitotic indices/phases compared to the other single component preparations with respect to the positive control (methyl methanesulphonate). It was also noted that there was a non-significant difference (p > 0.05) between the concentrations of composites and the negative control in the toxicity trial. Studying in parallel trials showed an increased prevalence, potential risk factors, and antibiotic resistance in S. aureus. The composites in a well diffusion trial showed the highest percentage increase in the zone of inhibition in the case of GT (58.42%), followed by GMT (46.15%), GC (40.65%), GMC (40%), GMA (28.72%), and GA (21.75%) compared to the antibiotics alone. A broth microdilution assay showed the lowest minimum inhibitory concentration (MIC) in the case of GMA (9.766 ± 00 µg/mL), followed by that of GT (13.02 ± 5.64 µg/mL), GMC (19.53 ± 0.00 µg/mL), GA (26.04 ± 11.28 µg/mL), GMT (26.04 ± 11.28 µg/mL), MG (39.06 ± 0.00 µg/mL), and GC (39.06 ± 0.00 µg/mL). The study thus concludes the effective tackling of multiple-drug-resistant S. aureus with sodium-alginate-stabilized MgO nanoparticles and antibiotics, whereas toxicity proved to be negligible for these composites.

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