Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 81
Filtrar
1.
Br J Cancer ; 2024 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-39369054

RESUMO

BACKGROUND: Cancer stem-like cells (CSLCs) drive tumour progression and chemoresistance. The concerted efforts of EXO1 and TLS polymerases safeguard DNA integrity against chemotherapeutic drugs. In absence of potential drug targets, non-small cell lung carcinoma (NSCLC) patients have few therapeutic options. In current scenario, microRNAs offer a potential avenue for eradicating CSLCs. METHODS: EXO1 downregulation impact on CSLCs expansion was assessed via flow cytometry. Co-localisation of EXO1, Polη and Polι was validated through co-immunoprecipitation and confocal-imaging. The effects of co-downregulation of Polη and Polι on CSLC survival, repair synthesis, and mutagenesis were evaluated using flow cytometry and immunohistochemistry in cell lines and xenografts. MicroRNA targeting EXO1 was studied for its role in CSLCs regulation. RESULTS: EXO1 downregulation in NSCLC CSLCs induces DNA lesions, triggering apoptosis and enhances cisplatin sensitivity. It collaborates with Polη and Polι in DNA repair, contributing to cisplatin resistance in CSLCs. Absence of Polη and Polι impairs repair and reduces cisplatin-induced mutagenesis. Co-downregulation of Polη and Polι in xenografts reduces tumour proliferation significantly. MiR-3163 overexpression sensitises CSLCs to cisplatin via targeting EXO1/Polη/Polι axis, as shown in mechanistic studies. CONCLUSION: This study unveils a novel regulatory pathway involving EXO1/Polη/Polι axis and miR-3163, providing insights into CSLCs regulation in NSCLC. EXO1/Polη/Polι axis targeted by miR-3163, resulting in the inhibition of cell growth and induction of apoptosis in NSCLC CSLCs.

2.
Biochem Biophys Res Commun ; 712-713: 149907, 2024 06 18.
Artigo em Inglês | MEDLINE | ID: mdl-38636303

RESUMO

Over the past decades, cancer stem cells (CSCs) have emerged as a critical subset of tumor cells associated with tumor recurrence and resistance to chemotherapy. Understanding the mechanisms underlying CSC-mediated chemoresistance is imperative for improving cancer therapy outcomes. This study delves into the regulatory role of NEIL1, a DNA glycosylase, in chemoresistance in ovarian CSCs. We first observed a decreased expression of NEIL1 in ovarian CSCs, suggesting its potential involvement in CSC regulation. Using pan-cancer analysis, we confirmed the diminished NEIL1 expression in ovarian tumors compared to normal tissues. Furthermore, NEIL1 downregulation correlated with an increase in stemness markers and enrichment of CSCs, highlighting its role in modulating CSC phenotype. Further mechanistic investigation revealed an inverse correlation between NEIL1 and RAD18 expression in ovarian CSCs. NEIL1 depletion led to heightened RAD18 expression, promoting chemoresistance possibly via enhancing Translesion DNA Synthesis (TLS)-mediated DNA lesion bypass. Moreover, dowregulation of NEIL1 results in reduced DNA damage accumulation and suppressed apoptosis in ovarian cancer. Overall, our findings unveil a novel mechanism involving NEIL1 and RAD18 in regulating chemoresistance in ovarian CSCs. Targeting this NEIL1-RAD18 axis may offer promising therapeutic strategies for combating chemoresistance and improving ovarian cancer treatment outcomes.


Assuntos
DNA Glicosilases , Proteínas de Ligação a DNA , Resistencia a Medicamentos Antineoplásicos , Células-Tronco Neoplásicas , Neoplasias Ovarianas , Regulação para Cima , Humanos , Feminino , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , DNA Glicosilases/metabolismo , DNA Glicosilases/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Dano ao DNA , Apoptose/efeitos dos fármacos , Apoptose/genética
3.
Semin Cancer Biol ; 86(Pt 2): 568-579, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35378273

RESUMO

Ovarian cancer is a leading cause of death among women globally often characterized by poor prognosis and aggressive tumor growth. The therapeutic outcomes of ovarian cancer patients are majorly limited by the development of acquired chemo/radioresistance and the lack of targeted therapies. The tumor microenvironment (TME) comprises a diverse population of cells including adipocytes, fibroblasts, tumor cells, and immune cells which play an imperative role in promoting tumor growth, invasion, and malignant phenotypes of cancer cells. The cells present in TME secrete various inflammatory mediators including chemokines and cytokines, which regulate the tumor progression and metastasis. This review article highlights new insights about the general mechanisms associated with chemokines-mediated cell proliferation, inflammation, tumor initiation, progression, metastasis, chemoresistance, and immune evasion in ovarian cancer. We also discuss the microRNAs (miRNAs) regulating the oncogenic potential of chemokines. Overall, this is a comparatively less explored area that could provide important insights into ovarian cancer development and a promising avenue for targeted therapy of ovarian cancer.


Assuntos
Resistencia a Medicamentos Antineoplásicos , Neoplasias Ovarianas , Feminino , Humanos , Resistencia a Medicamentos Antineoplásicos/genética , Microambiente Tumoral/genética , Quimiocinas/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Carcinoma Epitelial do Ovário
4.
Int J Biometeorol ; 67(1): 165-180, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36323951

RESUMO

Pigeon pea is the second most important grain legume in India, primarily grown under rainfed conditions. Any changes in agro-climatic conditions will have a profound influence on the productivity of pigeon pea (Cajanus cajan) yield and, as a result, the total pulse production of the country. In this context, weather-based crop yield prediction will enable farmers, decision-makers, and administrators in dealing with hardships. The current study examines the application of the stepwise linear regression method, supervised machine learning algorithms (support vector machines (SVM) and random forest (RF)), shrinkage regression approaches (least absolute shrinkage and selection operator (LASSO) or elastic net (ENET)), and artificial neural network (ANN) model for pigeon pea yield prediction using long-term weather data. Among the approaches, ANN resulted in a higher coefficient of determination (R2 = 0.88-0.99), model efficiency (0.88-1.00) with subsequent lower normalised root mean square error (nRMSE) during calibration (1.13-12.55%), and validation (0.33-21.20%) over others. The temperature alone or its interaction with other weather parameters was identified as the most influencing variables in the study area. The Pearson correlation coefficients were also determined for the observed and predicted yield. Those values also showed ANN as the best model with correlation values ranging from 0.939 to 0.999 followed by RF (0.955-0.982) and LASSO (0.880-0.982). However, all the approaches adopted in the study were outperformed the statistical method, i.e. stepwise linear regression with lower error values and higher model efficiency. Thus, these approaches can be effectively used for precise yield prediction of pigeon pea over different districts of Karnataka in India.


Assuntos
Cajanus , Índia , Tempo (Meteorologia) , Aprendizado de Máquina , Redes Neurais de Computação
5.
Field Crops Res ; 302: 109078, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37840837

RESUMO

Context or problem: In the Indian state of Odisha, rice-based system productivity is poor due to: (i) low rice yield in the monsoon (wet) season (2-4 t ha-1 compared to 6-8 t ha-1 in Punjab or Haryana); and (ii) limited cropping during the post-monsoon (dry) season (59% of the wet season rice area is left fallow in the dry season). Objective: Our study identifies strategies for increasing rice-based system productivity through: (i) alternative crop establishment methods in the wet season (Dry-Direct Seeded Rice or DSR, and mechanical puddled transplanted rice or PTR-M) to traditional methods such as broadcasting followed by post-emergence tillage (locally known as beushening) and manual random puddled transplanted rice (PTR-R); (ii) to identify rice-fallow areas suitable for pulse and oilseed cultivation in the dry season; and (iii) to evaluate the performance of short-duration pulses (green gram, Vigna radiata; black gram, Vigna mungo), and oilseeds (Brassica rapa var. toria, Helianthus annuus) in rice-fallow areas in the dry season. Methods: On-farm experiments were conducted between 2017 and 2019 in three districts of Odisha (Bhadrak, Cuttack and Mayurbhanj) to evaluate DSR compared to beushening and PTR-R; and PTR-M compared to PTR-R and manual line puddled transplanted rice (PTR-L) in the wet season. The data from Landsat-8 Operational Land Imager (OLI) and Sentinel-1satellite sensors was used to identify rice-fallow areas, and the daily SMAP (Soil Moisture Active Passive) L-band soil moisture was used for mapping suitable rice-fallow areas for growing pulses and oilseeds. Short duration crops were evaluated in suitable rice-fallow areas. Results: In the wet season, DSR (range -4 to + 53%) had a significant effect on rice yield over beushening. Similarly, PTR-M consistently increased rice yield by 16-26% over PTR-R, and by 5-23% over PTR-L. In the dry season, pulse crops (green gram and black gram) performed well compared to Indian mustard under rainfed cultivation. However, under irrigated conditions, dry-season rice yield was more productive than the rice equivalent yield of green gram, black gram and sunflower. We found that 1.03 M ha (i.e., ∼50%) of total rice-fallow areas of 2.1 M ha were suitable for growing short duration green gram and black gram in the dry season. Conclusions: We conclude that system productivity and cropping intensity can be increased by adoption of DSR and PTR-M in the wet season, and growing of green gram and black gram in the dry season. Implications: Odisha state can potentially produce an additional 0.67 million tonnes pulses if suitable rice-fallow areas are brought under green gram and black gram cultivation in the dry the season.

6.
J Cell Physiol ; 237(7): 3095-3108, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35621221

RESUMO

Endometriosis is a benign gynecological condition characterized by increased growth, inflammation, invasion, and angiogenesis, partly regulated by a class of enzymes called matrix metalloproteinases (MMPs). The importance of a few MMPs, e.g., MMP-9, -3, and -7 has been studied in endometriosis progression. Although MMP-13 plays an essential role in bone regeneration and cancer, no report has been found on the part of MMP-13 and endometriosis progression. We found the upregulation of MMP-13 expression and activity in patients having endometriosis in the eastern Indian population. In addition, the -77A/G polymorphism of the MMP13 promoter (rs: 2252070) is associated with regulating transcription and subsequent susceptibility to disease. In eastern Indian case-control groups, the effect of the -77A/G single-nucleotide polymorphism on MMP13 promoter activity and its relationship with endometriosis susceptibility was studied. The AG genotype was shown to be more predisposed to endometriosis risk than the GG genotype (p: 0.02; odds ratio [OR]: 1.65, 95% confidence interval [CI]: 1.10-2.49), also AG genotype was more frequent in late-stage patients compared to early-stage (p: 0.03, OR: 2.0, 95% CI: 1.09-3.66). Furthermore, the MMP13 gene levels were greater in AA compared to GG individuals. Additionally, MMP13 promoter-reporter experiments in cultured endometrial epithelial cells and in silico analyses both demonstrated increased transcriptional activity near the G to A transition under basal/IL-1ß -induced/c-FOS overexpressed condition. Overall, c-FOS tighter binding to the A allele-carrying promoter enhances MMP13 transcription, which is further amplified by IL-1ß due to increased c-FOS phosphorylation, promoting MMP-13 production and endometriosis risk.


Assuntos
Endometriose , Metaloproteinase 13 da Matriz/genética , Alelos , Endometriose/metabolismo , Feminino , Predisposição Genética para Doença , Humanos , Interleucina-1beta/genética , Metaloproteinases da Matriz/genética , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-fos/genética
7.
J Exp Bot ; 73(16): 5715-5729, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35728801

RESUMO

Crop multi-model ensembles (MME) have proven to be effective in increasing the accuracy of simulations in modelling experiments. However, the ability of MME to capture crop responses to changes in sowing dates and densities has not yet been investigated. These management interventions are some of the main levers for adapting cropping systems to climate change. Here, we explore the performance of a MME of 29 wheat crop models to predict the effect of changing sowing dates and rates on yield and yield components, on two sites located in a high-yielding environment in New Zealand. The experiment was conducted for 6 years and provided 50 combinations of sowing date, sowing density and growing season. We show that the MME simulates seasonal growth of wheat well under standard sowing conditions, but fails under early sowing and high sowing rates. The comparison between observed and simulated in-season fraction of intercepted photosynthetically active radiation (FIPAR) for early sown wheat shows that the MME does not capture the decrease of crop above ground biomass during winter months due to senescence. Models need to better account for tiller competition for light, nutrients, and water during vegetative growth, and early tiller senescence and tiller mortality, which are exacerbated by early sowing, high sowing densities, and warmer winter temperatures.


Assuntos
Mudança Climática , Triticum , Biomassa , Estações do Ano , Temperatura
8.
Biochem Biophys Res Commun ; 571: 26-31, 2021 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-34303192

RESUMO

The pandemic of SARS-CoV-2 has necessitated expedited research efforts towards finding potential antiviral targets and drug development measures. While new drug discovery is time consuming, drug repurposing has been a promising area for elaborate virtual screening and identification of existing FDA approved drugs that could possibly be used for targeting against functions of various proteins of SARS-CoV-2 virus. RNA dependent RNA polymerase (RdRp) is an important enzyme for the virus that mediates replication of the viral RNA. Inhibition of RdRp could inhibit viral RNA replication and thus new virus particle production. Here, we screened non-nucleoside antivirals and found three out of them to be strongest in binding to RdRp out of which two retained binding even using molecular dynamic simulations. We propose these two drugs as potential RdRp inhibitors which need further in-depth testing.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , RNA-Polimerase RNA-Dependente de Coronavírus/antagonistas & inibidores , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/enzimologia , Amidas/farmacologia , Antivirais/química , Benzimidazóis/farmacologia , COVID-19/virologia , Carbamatos/farmacologia , Domínio Catalítico , Simulação por Computador , RNA-Polimerase RNA-Dependente de Coronavírus/química , Ciclopropanos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Reposicionamento de Medicamentos , Fluorenos/farmacologia , Humanos , Lactamas Macrocíclicas/farmacologia , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Pandemias , Prolina/análogos & derivados , Prolina/farmacologia , Conformação Proteica , Quinoxalinas/farmacologia , Sulfonamidas/farmacologia
9.
J Autoimmun ; 118: 102614, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33578119

RESUMO

Psoriasis is an inflammatory skin disease with complex pathogenesis and multiple etiological factors. Besides the essential role of autoreactive T cells and constellation of cytokines, the discovery of IL-23/Th17 axis as a central signaling pathway has unraveled the mechanism of accelerated inflammation in psoriasis. This has provided insights into psoriasis pathogenesis and revolutionized the development of effective biological therapies. Moreover, genome-wide association studies have identified several candidate genes and susceptibility loci associated with this disease. Although involvement of cellular innate and adaptive immune responses and dysregulation of immune cells have been implicated in psoriasis initiation and maintenance, there is still a lack of unifying mechanism for understanding the pathogenesis of this disease. Emerging evidence suggests that psoriasis is a high-mortality disease with additional burden of comorbidities, which adversely affects the treatment response and overall quality of life of patients. Furthermore, changing trends of psoriasis-associated comorbidities and shared patterns of genetic susceptibility, risk factors and pathophysiological mechanisms manifest psoriasis as a multifactorial systemic disease. This review highlights the recent progress in understanding the crucial role of different immune cells, proinflammatory cytokines and microRNAs in psoriasis pathogenesis. In addition, we comprehensively discuss the involvement of various complex signaling pathways and their interplay with immune cell markers to comprehend the underlying pathophysiological mechanism, which may lead to exploration of new therapeutic targets and development of novel treatment strategies to reduce the disastrous nature of psoriasis and associated comorbidities.


Assuntos
Interleucina-23/metabolismo , Psoríase/imunologia , Células Th17/imunologia , MicroRNA Circulante/metabolismo , Comorbidade , Regulação da Expressão Gênica/imunologia , Humanos , Imunidade Inata/genética , Psoríase/sangue , Psoríase/epidemiologia , Psoríase/genética , Qualidade de Vida , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Células Th17/metabolismo
10.
Molecules ; 26(22)2021 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-34833873

RESUMO

The novel coronavirus disease (COVID-19), the reason for worldwide pandemic, has already masked around 220 countries globally. This disease is induced by Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). Arising environmental stress, increase in the oxidative stress level, weak immunity and lack of nutrition deteriorates the clinical status of the infected patients. Though several researches are at its peak for understanding and bringing forward effective therapeutics, yet there is no promising solution treating this disease directly. Medicinal plants and their active metabolites have always been promising in treating many clinical complications since time immemorial. Mother nature provides vivid chemical structures, which act multi-dimensionally all alone or synergistically in mitigating several diseases. Their unique antioxidant and anti-inflammatory activity with least side effects have made them more effective candidate for pharmacological studies. These medicinal plants inhibit attachment, encapsulation and replication of COVID-19 viruses by targeting various signaling molecules such as angiotensin converting enzyme-2, transmembrane serine protease 2, spike glycoprotein, main protease etc. This property is re-examined and its potency is now used to improve the existing global health crisis. This review is an attempt to focus various antiviral activities of various noteworthy medicinal plants. Moreover, its implications as prophylactic or preventive in various secondary complications including neurological, cardiovascular, acute kidney disease, liver disease are also pinpointed in the present review. This knowledge will help emphasis on the therapeutic developments for this novel coronavirus where it can be used as alone or in combination with the repositioned drugs to combat COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , Reposicionamento de Medicamentos , Compostos Fitoquímicos/uso terapêutico , Enzima de Conversão de Angiotensina 2/antagonistas & inibidores , Enzima de Conversão de Angiotensina 2/metabolismo , COVID-19/complicações , COVID-19/patologia , COVID-19/virologia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Humanos , Compostos Fitoquímicos/química , Compostos Fitoquímicos/metabolismo , Compostos Fitoquímicos/farmacologia , Plantas Medicinais/química , Plantas Medicinais/metabolismo , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos
11.
Int J Mol Sci ; 21(19)2020 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-32992449

RESUMO

Emerging shreds of evidence suggest that tumor-associated macrophages (TAMs) modulate various hallmarks of cancer during tumor progression. Tumor microenvironment (TME) prime TAMs to execute important roles in cancer development and progression, including angiogenesis, matrix metalloproteinases (MMPs) secretion, and extracellular matrix (ECM) disruption. MicroRNAs (miRNAs) are critical epigenetic regulators, which modulate various functions in diverse types of cells, including macrophages associated with TME. In this review article, we provide an update on miRNAs regulating differentiation, maturation, activation, polarization, and recruitment of macrophages in the TME. Furthermore, extracellular miRNAs are secreted from cancerous cells, which control macrophages phenotypic plasticity to support tumor growth. In return, TAMs also secrete various miRNAs that regulate tumor growth. Herein, we also describe the recent updates on the molecular connection between tumor cells and macrophages. A better understanding of the interaction between miRNAs and TAMs will provide new pharmacological targets to combat cancer.


Assuntos
MicroRNAs/metabolismo , Neoplasias/imunologia , Neoplasias/metabolismo , Microambiente Tumoral/imunologia , Macrófagos Associados a Tumor/imunologia , Macrófagos Associados a Tumor/metabolismo , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Polaridade Celular/genética , Polaridade Celular/imunologia , Progressão da Doença , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Ativação de Macrófagos/genética , Ativação de Macrófagos/imunologia , MicroRNAs/genética , Neoplasias/genética
12.
Trop Anim Health Prod ; 52(5): 2585-2592, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32445160

RESUMO

Female fertility in domestic animals in India has exhaustively suffered owing to indiscriminate breeding with single objective of increasing milk production. First lactation data on 7782 Mehsana buffaloes sired by 184 bulls maintained under field progeny testing programme at Dudhsagar Research and Development Association, Dudhsagar Dairy, Mehsana, over a period of 24 years were used for study of fertility traits viz. days open, first to successful service period (FTSS) and daughter pregnancy rate (DPR) and production traits viz. first lactation milk yield (FLMY), first lactation fat yield (FLFY) and average fat percentage (AFP). The voluntary waiting period (VWP) was standardised based on the higher estimates for FLMY and FLMY per unit first calving interval. VWP for Mehsana buffaloes was standardised as 63 days after first calving and consequently DPR of Mehsana buffalo was also estimated as 31%. Fertility traits were further evaluated in terms of production traits. Regression analysis revealed that the increase in 1 kg FLFY and 100 kg FLMY led to the increase of First Service Period by 0.013 days and decrease in the DPR by 1.89%, respectively. Increase in milk yield led to increase in FTSS. However, for each 100 kg increase in fat yield and 1% increase in AFP, there is increase in DPR by 0.08% and 0.051%, respectively. Based on the present findings, it may be recommended to have a breeding programme which give due weightage to both production and fertility traits.


Assuntos
Búfalos/fisiologia , Fertilidade/genética , Animais , Búfalos/genética , Colostro , Feminino , Fertilidade/fisiologia , Índia , Lactação , Leite , Gravidez , Taxa de Gravidez , Análise de Regressão
13.
Proc Natl Acad Sci U S A ; 112(14): 4411-6, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25831546

RESUMO

Cancer stem cells (CSCs) with enhanced tumorigenicity and chemoresistance are believed to be responsible for treatment failure and tumor relapse in ovarian cancer patients. However, it is still unclear how CSCs survive DNA-damaging agent treatment. Here, we report an elevated expression of DNA polymerase η (Pol η) in ovarian CSCs isolated from both ovarian cancer cell lines and primary tumors, indicating that CSCs may have intrinsically enhanced translesion DNA synthesis (TLS). Down-regulation of Pol η blocked cisplatin-induced CSC enrichment both in vitro and in vivo through the enhancement of cisplatin-induced apoptosis in CSCs, indicating that Pol η-mediated TLS contributes to the survival of CSCs upon cisplatin treatment. Furthermore, our data demonstrated a depletion of miR-93 in ovarian CSCs. Enforced expression of miR-93 in ovarian CSCs reduced Pol η expression and increased their sensitivity to cisplatin. Taken together, our data suggest that ovarian CSCs have intrinsically enhanced Pol η-mediated TLS, allowing CSCs to survive cisplatin treatment, leading to tumor relapse. Targeting Pol η, probably through enhancement of miR-93 expression, might be exploited as a strategy to increase the efficacy of cisplatin treatment.


Assuntos
Cisplatino/química , DNA Polimerase Dirigida por DNA/metabolismo , Neoplasias Ovarianas/genética , Animais , Linhagem Celular Tumoral , Sobrevivência Celular , DNA/química , Dano ao DNA , Reparo do DNA , DNA Polimerase Dirigida por DNA/genética , Regulação para Baixo , Feminino , Citometria de Fluxo , Humanos , Camundongos , Camundongos Nus , MicroRNAs/genética , Metástase Neoplásica , Recidiva Local de Neoplasia , Transplante de Neoplasias , Células-Tronco Neoplásicas/citologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Ovarianas/metabolismo , Recidiva
14.
Nucleic Acids Res ; 43(16): 7838-49, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26130719

RESUMO

The expression of DNA damage-binding protein 2 (DDB2) has been linked to the prognosis of ovarian cancer and its underlying transcription regulatory function was proposed to contribute to the favorable treatment outcome. By applying gene microarray analysis, we discovered neural precursor cell expressed, developmentally downregulated 4-Like (NEDD4L) as a previously unidentified downstream gene regulated by DDB2. Mechanistic investigation demonstrated that DDB2 can bind to the promoter region of NEDD4L and recruit enhancer of zeste homolog 2 histone methyltransferase to repress NEDD4L transcription by enhancing histone H3 lysine 27 trimethylation (H3K27me3) at the NEDD4L promoter. Given that NEDD4L plays an important role in constraining transforming growth factor ß signaling by targeting activated Smad2/Smad3 for degradation, we investigated the role of DDB2 in the regulation of TGF-ß signaling in ovarian cancer cells. Our data indicate that DDB2 enhances TGF-ß signal transduction and increases the responsiveness of ovarian cancer cells to TGF-ß-induced growth inhibition. The study has uncovered an unappreciated regulatory mode that hinges on the interaction between DDB2 and NEDD4L in human ovarian cancer cells. The novel mechanism proposes the DDB2-mediated fine-tuning of TGF-ß signaling and its downstream effects that impinge upon tumor growth in ovarian cancers.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Ovarianas/genética , Fator de Crescimento Transformador beta/farmacologia , Ubiquitina-Proteína Ligases/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação para Baixo , Proteína Potenciadora do Homólogo 2 de Zeste , Feminino , Histonas/metabolismo , Humanos , Ubiquitina-Proteína Ligases Nedd4 , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Complexo Repressor Polycomb 2/metabolismo , Regiões Promotoras Genéticas , Transdução de Sinais
15.
Carcinogenesis ; 37(2): 129-38, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26717995

RESUMO

Discretely orchestrated chromatin condensation is important for chromosome protection from DNA damage. However, it is still unclear how different chromatin states affect the formation and repair of nucleotide excision repair (NER) substrates, e.g. ultraviolet (UV)-induced cyclobutane pyrimidine dimers (CPD) and the pyrimidine (6-4) pyrimidone photoproducts (6-4PP), as well as cisplatin-induced intrastrand crosslinks (Pt-GG). Here, by using immunofluorescence and chromatin immunoprecipitation assays, we have demonstrated that CPD, which cause minor distortion of DNA double helix, can be detected in both euchromatic and heterochromatic regions, while 6-4PP and Pt-GG, which cause major distortion of DNA helix, can exclusively be detected in euchromatin, indicating that the condensed chromatin environment specifically interferes with the formation of these DNA lesions. Mechanistic investigation revealed that the class III histone deacetylase SIRT1 is responsible for restricting the formation of 6-4PP and Pt-GG in cells, probably by facilitating the maintenance of highly condensed heterochromatin. In addition, we also showed that the repair of CPD in heterochromatin is slower than that in euchromatin, and DNA damage binding protein 2 (DDB2) can promote the removal of CPD from heterochromatic region. In summary, our data provide evidence for differential formation and repair of DNA lesions that are substrates of NER. Both the sensitivity of DNA to damage and the kinetics of repair can be affected by the underlying level of chromatin compaction.


Assuntos
Dano ao DNA/fisiologia , Reparo do DNA/fisiologia , Eucromatina/química , Heterocromatina/química , Células Cultivadas , Imunoprecipitação da Cromatina , Imunofluorescência , Humanos , Immunoblotting , Dímeros de Pirimidina/metabolismo , Interferência de RNA
16.
Tumour Biol ; 37(4): 5645-51, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26581907

RESUMO

The level of microRNA-93 (miR-93) in tumors has been recently reported to be negatively correlated with survival of lung cancer patients. Considering that the most devastating aspect of lung cancer is metastasis, which can be promoted by transforming growth factor-ß (TGF-ß)-induced epithelial-to-mesenchymal transition (EMT), we sought to determine whether miR-93 is involved in this process. Here, we report that a previously unidentified target of miR-93, neural precursor cell expressed developmentally downregulated gene 4-like (NEDD4L), is able to mediate TGF-ß-mediated EMT in lung cancer cells. miR-93 binds directly to the 3'-UTR of the NEDD4L messenger RNA (mRNA), leading to a downregulation of NEDD4L expression at the protein level. We next demonstrated that the downregulation of NEDD4L enhanced, while overexpression of NEDD4L reduced TGF-ß signaling, reflected by increased phosphorylation of SMAD2 in the lung cancer cell line after TGF-ß treatment. Furthermore, overexpression of miR-93 in lung cancer cells promoted TGF-ß-induced EMT through downregulation of NEDD4L. The analysis of publicly available gene expression array datasets indicates that low NEDD4L expression correlates with poor outcomes among patients with lung cancer, further supporting the oncogenic role of miR-93 in lung tumorigenesis and metastasis.


Assuntos
Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Fator de Crescimento Transformador beta/genética , Ubiquitina-Proteína Ligases/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Complexos Endossomais de Distribuição Requeridos para Transporte/biossíntese , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , MicroRNAs/biossíntese , Ubiquitina-Proteína Ligases Nedd4 , Metástase Neoplásica , Estadiamento de Neoplasias , Proteína Smad2/biossíntese , Ubiquitina-Proteína Ligases/biossíntese
17.
Tumour Biol ; 37(10): 14183-14191, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27553023

RESUMO

Radiotherapy resistance is one of the major factors limiting the efficacy of radiotherapy in lung cancer patients. The extensive investigations indicate the diversity in the mechanisms underlying radioresistance. Here, we revealed that DNA damage binding protein 2 (DDB2) is a potential regulator in the radiosensitivity of non-small cell lung cancer (NSCLC) cells. DDB2, originally identified as a DNA damage recognition factor in the nucleotide excision repair, promotes the survival and inhibits the apoptosis of NSCLC cell lines upon ionizing radiation (IR). Mechanistic investigations demonstrated that DDB2 is able to facilitate IR-induced phosphorylation of Chk1, which plays a critical role in the cell cycle arrest and DNA repair in response to IR-induced DNA double-strand breaks (DSBs). Indeed, knockdown of DDB2 compromised the G2 arrest in the p53-proficient A549 cell line and reduced the efficiency of homologous recombination (HR) repair. Taken together, our data indicate that the expression of DDB2 in NSCLC could be used as a biomarker to predict radiosensitivity of the patients. Targeting Chk1 can be used to increase the efficacy of radiotherapy in patients of NSCLC possessing high levels of DDB2.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Quebras de DNA de Cadeia Dupla/efeitos da radiação , Proteínas de Ligação a DNA/metabolismo , Neoplasias Pulmonares/radioterapia , Tolerância a Radiação/genética , Reparo de DNA por Recombinação/genética , Apoptose/efeitos da radiação , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Pontos de Checagem do Ciclo Celular/efeitos da radiação , Proliferação de Células/efeitos da radiação , Proteínas de Ligação a DNA/genética , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Fosforilação , Radiação Ionizante , Reparo de DNA por Recombinação/efeitos da radiação , Células Tumorais Cultivadas
18.
Nucleic Acids Res ; 42(15): e122, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25030906

RESUMO

Inundation of evolutionary markers expedited in Human Genome Project and 1000 Genome Consortium has necessitated pruning of redundant and dependent variables. Various computational tools based on machine-learning and data-mining methods like feature selection/extraction have been proposed to escape the curse of dimensionality in large datasets. Incidentally, evolutionary studies, primarily based on sequentially evolved variations have remained un-facilitated by such advances till date. Here, we present a novel approach of recursive feature selection for hierarchical clustering of Y-chromosomal SNPs/haplogroups to select a minimal set of independent markers, sufficient to infer population structure as precisely as deduced by a larger number of evolutionary markers. To validate the applicability of our approach, we optimally designed MALDI-TOF mass spectrometry-based multiplex to accommodate independent Y-chromosomal markers in a single multiplex and genotyped two geographically distinct Indian populations. An analysis of 105 world-wide populations reflected that 15 independent variations/markers were optimal in defining population structure parameters, such as FST, molecular variance and correlation-based relationship. A subsequent addition of randomly selected markers had a negligible effect (close to zero, i.e. 1 × 10(-3)) on these parameters. The study proves efficient in tracing complex population structures and deriving relationships among world-wide populations in a cost-effective and expedient manner.


Assuntos
Cromossomos Humanos Y/química , Evolução Molecular , Análise por Conglomerados , Marcadores Genéticos , Genética Populacional/métodos , Técnicas de Genotipagem , Haplótipos , Humanos , Índia , Masculino , Filogenia , Análise de Componente Principal , População Branca/genética
19.
Nanomedicine ; 12(5): 1375-85, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26964481

RESUMO

In order to promote the natural healing process, drug-functionalized nanofibrous transdermal substitute was fabricated using gellan as chief polymer and polyvinyl alcohol (PVA) as supporting polymer via electrospinning technique. These fabricated nanofibers physiochemically mimic the extracellular matrix (ECM) which supports the cell growth. For neo-tissue regeneration in a sterilized environment, amoxicillin (Amx) was entrapped within these nanofibers. Entrapment of Amx in the nanofibers was confirmed by FESEM, FTIR, XRD and TG analysis. In vitro cell culture studies revealed that the fabricated non-cytotoxic nanofibers promoted enhance cell adherence and proliferation of human keratinocytes. A preliminary in vivo study performed on rat model for full thickness skin excision wound demonstrated the prompt re-epithelialization in early phase and quicker collagen deposition in later phases of wound healing in case of Amx-functionalized gellan/PVA nanofibers. Data collectively confirmed the potential usage of gellan based electrospun nanofibers as transdermal substitute for faster skin restoration.


Assuntos
Nanofibras , Álcool de Polivinil , Cicatrização , Administração Cutânea , Animais , Colágeno , Humanos , Ratos , Regeneração , Fenômenos Fisiológicos da Pele , Alicerces Teciduais
20.
J Med Genet ; 50(1): 34-42, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23240095

RESUMO

BACKGROUND: Genome-wide studies have identified both human leucocyte antigen (HLA) and non-HLA regions in association with leprosy. Involvement of novel functional loci within these regions has been proposed by us earlier. METHODS: We investigated the role of 23 single nucleotide polymorphisms (SNPs) in IL12B and IL12RB2 in a total of 2345 individuals from India, using MassArray platform, along with the copy number variations in IL23R, IL12RB2 and IL10 genes in a representative set of 257 individuals, using real-time PCR. RESULTS: SNP rs2853694 in IL12B gene (AA vs AC+CC, p=2.6E-04, OR=1.42 (1.17-1.70)) showed an association with leprosy. Pairwise interaction analysis followed by combined analysis of multiple SNPs identified that IL12B, TNF and BTNL2-DRA inter-genic SNPs provided a major risk towards leprosy (p=2.6E-08, OR=3.94 (2.43-6.38)), showing a further increase (p=3.6E-14) for combined risk genotype interactions. On the other hand, IL12B, BAT1, NFKBIL1 and LTA SNPs together showed a disposition towards protection (p=0.000011, OR=0.32 (0.19-0.53)) with a further increase (p=6.38E-10) for combined protective genotype-interactions. Copy number variation analysis showed an increased copy number of the IL23R gene (PB=36.4%, controls=20.2%; p=0.026) associated with the pauci-bacillary form of leprosy, which correlated with a trend towards enhanced expression in memory T cells in a preliminary observation. CONCLUSIONS: The observations made here highlight the importance of interaction between specific genetic backgrounds of immune response related genes in the outcome of Mycobacterium leprae infection.


Assuntos
Variações do Número de Cópias de DNA , Predisposição Genética para Doença , Subunidade p40 da Interleucina-12/genética , Hanseníase/genética , Polimorfismo de Nucleotídeo Único , Receptores de Interleucina/genética , Adulto , Alelos , Estudos de Casos e Controles , Feminino , Frequência do Gene , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Adulto Jovem
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa