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1.
Heliyon ; 10(13): e33998, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39055821

RESUMO

Ajuga bracteosa (Ab) has tremendous medicinal value with long-established disease curing potential. The present study aimed to assess the hepatoprotective potential of Ab extracts in paracetamol-induced hepatotoxicity in mice. Group I (normal control) were treated with saline 1 ml/kg BW orally for 7 days while Group II (toxicant control) received saline 1 ml/kg BW for 6 days and Paracetamol (1000 mg/kg BW) on day7of the treatment. Group III received Standard drug silymarin (100 mg/kg BW) for 6 days and Paracetamol (1000 mg/kg BW) on day 7of treatment. Groups IV andV were administered with methanol extract (ME) 200 mg/kg BW and aqueous extract (AE) 1000 mg/kg BW for 6 days and Paracetamol (1000 mg/kg BW) on day 7th of the study. Both extracts showed hepatoprotective potential against the toxic effects of paracetamol, evidenced by serum analysis of biomarkers involved in liver injury and histopathological findings. Hepatotoxic mice pretreated with Ab plant extract or silymarin exhibited significant decrease in ALP, AST, and ALT enzyme level while GSH levels were markedly increased. According to histological observations, groups treated with PCM (toxicant control) showed significant necrosis and lymphocyte infiltration, while groups treated with silymarin and Ajuga bracteosa plant extract showed preservation of the normal liver structural features. The phytochemical analysis of ME and AE of Ab showed the presence of glycosides, phenolic compounds, tannins, fats, saponins, flavonoids, terpenes, oils, and fats. The antioxidant activity of these two extracts was determined by nitric oxide assay, DPPH assay, and ferric reducing power assay. The methanolic extract exhibited the highest antioxidant potential (78.09 ± 0.0806). The antioxidant potential of aqueous extract was 73.08 ± 0.248. The reducing power for methanolic extract and ascorbic acid (standard) 500 µg/ml was 0.933 and 0.987 respectively. The anti-inflammatory activity of both extracts was demonstrated by in vitro methods, namely albumin denaturation, proteinase inhibition, and membrane stabilization assays. The study suggests that Ab extracts have competence for attenuating inflammation, oxidants, and hepatotoxicity.

2.
Int Immunopharmacol ; 126: 111186, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-37979454

RESUMO

The immune system frequently comprises immunological checkpoints. They serve as a barrier to keep the immune system from overreacting and damaging cells that are robust. Immune checkpoint inhibitors (ICIs) are utilized in immunotherapy to prevent the synergy of partner proteins of checkpoint proteins with auxiliary proteins. Moreover, the T cells may target malignant cells since the "off" signal cannot be conveyed. ICIs, which are mostly composed of monoclonal antibodies (mAbs) against cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) and anti- programmed death-1/programmed ligand 1 (anti-PD-1/PD-L1), might transform the context of cancer therapy. Further, more patients continued to exhibit adaptive resistance, even though several ICIs demonstrated convincing therapeutic benefits in selective tumor types. Immune checkpoint therapy's overall effectiveness is still lacking at this time. A popular area of study involves investigating additional immune checkpoint molecules. Recent research has found a number of fresh immune checkpoint targets, including NKG2A ligands, TIGIT, B7-H6 ligands, Galectin 3, TIM3, and so on. These targets have been focus of the study, and recent investigational approaches have shown encouraging outcomes. In this review article, we covered the development and present level understanding of these recently identified immune checkpoint molecules, its effectiveness and limitations.


Assuntos
Proteínas de Checkpoint Imunológico , Neoplasias , Humanos , Proteínas de Checkpoint Imunológico/metabolismo , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais/metabolismo , Imunoterapia/efeitos adversos , Antígeno CTLA-4/metabolismo , Linfócitos T , Antígeno B7-H1/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/patologia
3.
Heliyon ; 9(4): e15166, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37077690

RESUMO

Background: Recurrent miscarriage (RM) represents the spontaneous termination of two or more successive pregnancies. TNFα is a proinflammatory cytokine that is often considered harmful for embryonic development when expressed beyond normal levels. Aim: The study was conducted to assess the association between TNFα-308 polymorphism and RM pathogenesis. Methods: Samples of blood were obtained from patients and controls through venipuncture. The levels of TNFα in serum were measured by ELISA. TNFα gene promoter-associated single-nucleotide polymorphism was investigated with polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques with precise primers and the restriction endonuclease, NcoI. Results: Serum TNFα levels in patients were considerably high (p < 0.05) than controls. The genotype and allele frequencies for TNFα gene polymorphism differs significantly (p = 0.0089; p = 0.0043 respectively) between patients and controls. The TNFα-308 SNP exhibited a link with higher RM risk in heterozygous (GG vs. GA; OR: 3.086, 95% CI: 1.475-6.480; p: 0.0027), dominant (GG vs. GA + AA; OR: 2.919, 95% CI: 1.410-6.056, p: 0.0038), and allelic/codominant (G vs. A; OR: 2.449, 95% CI: 1.313-4.644, p: 0.0064) models. However, this SNP showed an insignificant association with higher and lower RM risk in homozygous (GG vs. AA; OR: 1.915, 95% CI: 0.3804-10.99, p: 0.6560) and recessive (AA vs. GA + GG; OR: 0.6596, 95% CI: 0.1152-3.297, p: >0.9999) models, respectively. Further, the TNFα-308G/A genotype frequencies were in concord with HWE both in the controls (χ2 = 3.235; p = 0.1985) and the patients (χ2 = 0.0117; p = 0.9942). Conclusion: The serum TNFα levels were significantly higher in the patients than the controls. The genotyping analysis also demonstrated that TNFα-308G/A SNP significantly increases the overall risk of RM, suggesting that the SNP modulates the TNFα gene expression and thereby increases serum TNFα levels that adversely affect the pregnancy outcome.

4.
Eur J Pharmacol ; 947: 175678, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36990262

RESUMO

Transforming growth factor-ß (TGFß) is a pleiotropic secretory cytokine exhibiting both cancer-inhibitory and promoting properties. It transmits its signals via Suppressor of Mother against Decapentaplegic (SMAD) and non-SMAD pathways and regulates cell proliferation, differentiation, invasion, migration, and apoptosis. In non-cancer and early-stage cancer cells, TGFß signaling suppresses cancer progression via inducing apoptosis, cell cycle arrest, or anti-proliferation, and promoting cell differentiation. On the other hand, TGFß may also act as an oncogene in advanced stages of tumors, wherein it develops immune-suppressive tumor microenvironments and induces the proliferation of cancer cells, invasion, angiogenesis, tumorigenesis, and metastasis. Higher TGFß expression leads to the instigation and development of cancer. Therefore, suppressing TGFß signals may present a potential treatment option for inhibiting tumorigenesis and metastasis. Different inhibitory molecules, including ligand traps, anti-sense oligo-nucleotides, small molecule receptor-kinase inhibitors, small molecule inhibitors, and vaccines, have been developed and clinically trialed for blocking the TGFß signaling pathway. These molecules are not pro-oncogenic response-specific but block all signaling effects induced by TGFß. Nonetheless, targeting the activation of TGFß signaling with maximized specificity and minimized toxicity can enhance the efficacy of therapeutic approaches against this signaling pathway. The molecules that are used to target TGFß are non-cytotoxic to cancer cells but designed to curtail the over-activation of invasion and metastasis driving TGFß signaling in stromal and cancer cells. Here, we discussed the critical role of TGFß in tumorigenesis, and metastasis, as well as the outcome and the promising achievement of TGFß inhibitory molecules in the treatment of cancer.


Assuntos
Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Fator de Crescimento Transformador beta/metabolismo , Transdução de Sinais , Diferenciação Celular , Carcinogênese , Microambiente Tumoral
5.
Plants (Basel) ; 11(24)2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36559700

RESUMO

Despite its limited exploration, Nymphaea mexicana Zucc. can be beneficial if pharmacology, isolation, and biological evaluation are given attention. It is an aquatic species that belongs to the family Nymphaeaceae. The thrust area of the work was the extraction, isolation, and biological evaluation of different extracts of the N. mexicana Zucc. plant. The primary goal of this research was to assess the antimicrobial, antioxidant, and anticancer activities of the extracts and to isolate the target naringenin compound. Comparative FT IR analysis of different extracts of this plant revealed the presence of functional groups of plant secondary metabolites, including polyphenols, flavonoids, terpenoids, esters, amines, glycosides, alkanes, alkaloids, fatty acids, and alcohols. Moderate free radical scavenging potential has been achieved for the various extracts via reducing power and DPPH assays. While cytotoxic activity was evaluated by colorimetric and lactate dehydrogenase cell viability tests on potent cancer cell lines. Lung adenocarcinoma epithelial cells (A-549), and breast cells (MC-7) were treated with MeOH extract. The antimicrobial activity against bacterial strains was evaluated using Gram-positive and -negative cultures, where maximum and minimum inhibition zones were recorded for different strains, including 1.6-25.6 µg/mL for Streptococcus aureus, using the agar well diffusion method. In addition, the anti-inflammatory activity of different extracts of N. mexicana Zucc. was evaluated in a nitrite radical scavenging assay with high concentrations of secondary metabolites, which are important against human pathogens and other diseases.

6.
J Clin Invest ; 132(20)2022 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-35943814

RESUMO

To understand how kidney donation leads to an increased risk of preeclampsia, we studied pregnant outbred mice with prior uninephrectomy and compared them with sham-operated littermates carrying both kidneys. During pregnancy, uninephrectomized (UNx) mice failed to achieve a physiological increase in the glomerular filtration rate and during late gestation developed hypertension, albuminuria, glomerular endothelial damage, and excess placental production of soluble fms-like tyrosine kinase 1 (sFLT1), an antiangiogenic protein implicated in the pathogenesis of preeclampsia. Maternal hypertension in UNx mice was associated with low plasma volumes, an increased rate of fetal resorption, impaired spiral artery remodeling, and placental ischemia. To evaluate potential mechanisms, we studied plasma metabolite changes using mass spectrometry and noted that l-kynurenine, a metabolite of l-tryptophan, was upregulated approximately 3-fold during pregnancy when compared with prepregnant concentrations in the same animals, consistent with prior reports suggesting a protective role for l-kynurenine in placental health. However, UNx mice failed to show upregulation of l-kynurenine during pregnancy; furthermore, when UNx mice were fed l-kynurenine in drinking water throughout pregnancy, their preeclampsia-like state was rescued, including a reversal of placental ischemia and normalization of sFLT1 levels. In aggregate, we provide a mechanistic basis for how impaired renal reserve and the resulting failure to upregulate l-kynurenine during pregnancy can lead to impaired placentation, placental hypoperfusion, an antiangiogenic state, and subsequent preeclampsia.


Assuntos
Hipertensão , Rim , Nefrectomia , Pré-Eclâmpsia , Animais , Feminino , Humanos , Hipertensão/metabolismo , Isquemia/metabolismo , Rim/metabolismo , Rim/fisiopatologia , Cinurenina/metabolismo , Camundongos , Nefrectomia/efeitos adversos , Placenta/metabolismo , Fator de Crescimento Placentário , Pré-Eclâmpsia/metabolismo , Gravidez , Triptofano/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo
7.
Semin Cancer Biol ; 86(Pt 2): 886-908, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35143992

RESUMO

Cancer is one of the biggest causes of mortality in the world. The advances in cancer research have taken us to distance in understanding the disease, which helps develop therapeutic strategies. Surgery and chemotherapy are the two main chosen routes of combat for cancer. These chemotherapeutic agents are good at targeting cancer, but many lack the specificity to make the distinction between healthy cells. Also, the toxicity of these chemotherapeutic agents is very high. This gap makes it quintessential to either look for better and safe agents or makes it possible for existing agents to meet these needs. Nanotechnology has the potential to deal with these unmet needs. Nanotechnology has been a hot topic recently due to its applications, one of these being nanomedicine. Studies have proven that cancer nanomedicine has a scope of being revolutionary. With the help of nanoparticles, we can make drugs specific for the cancer tissue; it can also help in increasing the bioavailability of the drug. A nanoparticle can be modified as such that it can carry the drug load that is required and deliver it to the specific target. In this review article, we have discussed the advances in nanomedicine and the current clinical status of various nanomedicines. We have extensively explored various strategies used to develop cancer nanomedicine while also discussing their mechanism of action.


Assuntos
Antineoplásicos , Neoplasias , Humanos , Sistemas de Liberação de Medicamentos , Nanomedicina , Neoplasias/tratamento farmacológico , Nanotecnologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Inflamação/tratamento farmacológico
8.
Drug Chem Toxicol ; 45(6): 2626-2636, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34555984

RESUMO

Orange red is a food and cosmetic coloring agent made by the amalgamation of two azo dyes carmoisine and sunset yellow. The current study demonstrates the effect of different concentrations of orange red on antioxidant status, inflammatory biomarkers (TNFα, IFNγ, IL1ß, IL6, COX-2, iNOS, and NFκB/p65), biochemical enzymes, and liver histology. In totality, 25 male Wistar rats were procured and arbitrarily alienated into 5 different groups each with 5 animals. Group I was taken as the control. Groups II-V were designated as treatment groups. Groups II and III were administered with (5 and 25 mg/kg b.wt.) and groups IV and V with (150 and 300 mg/kg b.wt.) of orange red via oral gavage for 30 days. It was observed that both low and high concentrations of orange red (25, 150, and 300 mg/kg) remarkably augmented the levels of serum inflammatory cytokines (TNFα, IFNγ, IL1ß, and IL6) and the protein and gene expression of COX-2, iNOS, and NFκB/p65. A significant decrease in glutathione reductase, glutathione peroxidase, glutathione-S-transferase, superoxidase dismutase, and catalase activity was observed with increasing concentration of orange red. Furthermore, an increase in the level of several vital biochemical parameters and damage severity to hepatic tissue was also found dose dependent.


Assuntos
Antioxidantes , Fator de Necrose Tumoral alfa , Animais , Masculino , Ratos , Antioxidantes/farmacologia , Compostos Azo/toxicidade , Biomarcadores/metabolismo , Catalase/metabolismo , Corantes/toxicidade , Ciclo-Oxigenase 2/genética , Citocinas/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glutationa Transferase/metabolismo , Interleucina-6 , NF-kappa B , Estresse Oxidativo , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo
9.
Int Immunopharmacol ; 99: 107984, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34303999

RESUMO

Cancer has been generally related to the possession of numerous mutations which interrupt important signaling pathways. Nevertheless, deregulated immunological signaling is considered as one of the key factors associated with the development and progression of cancer. The signaling pathways operate as modular network with different components interacting in a switch-like fashion with two proteins interplaying between each other leading to direct or indirect inhibition or stimulation of down-stream factors. Genetic, epigenetic, and transcriptomic alterations maintain the pathological conduit of different signaling pathways via affecting diverse mechanisms including cell destiny. At present, immunotherapy is one of the best therapies opted for cancer treatment. The cancer immunotherapy strategy includes harnessing the specificity and killing mechanisms of the immunological system to target and eradicate malignant cells. Targeted therapies utilizing several little molecules including Galunisertib, Astragaloside-IV, Melatonin, and Jervine capable of regulating key signaling pathways can effectively help in the management of different carcinomas.


Assuntos
Carcinoma/terapia , Imunomodulação/imunologia , Imunoterapia/métodos , Neoplasias/terapia , Animais , Humanos , Transdução de Sinais/efeitos dos fármacos , Microambiente Tumoral
10.
Curr Med Chem ; 28(39): 8036-8067, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33881968

RESUMO

Cancer is a multi-factorial health condition involving uncontrolled cell divisions. The disease has its roots in genetic mutation. This disease affects men, women, and even children. Chemotherapy, photodynamic, photothermal, and hormonal therapies have been used to treat this deadliest disease, but a huge percentage of patients have chances of disease recurrence or resistance. Nowadays, dysregulation in miRNAs is considered one of the key factors for the development and progression of different types of cancers as they control the expression of genes responsible for cell proliferation, growth, differentiation, and apoptosis. Dietary phytochemicals with anticancer properties have been gaining focus for cancer treatment since they have been found more effective in targeting cancer via regulating miRNAs expression. These phytochemicals have no side effects and are readily available at a low cost. Several dietary phytochemicals with regulatory effects on the expression of miRNAs have been reported, including curcumin, diallyl disulfide, 3, 30-diindolylmethane, ellagic acid, genistein, indole-3-carbinol, quercetin, resveratrol, and sulforaphane. They exert their regulatory effects against different cancers either by upregulating or downregulating different cancer signalling pathways and inhibiting their progression. Curcumin down-regulates SHH pathways, epigallocatechin-3-gallate regulates the Notch pathway and inhibits TGFß1/SMAD signalling, and resveratrol regulates the Wnt/ß-catenin pathway and carnosic acid-induced apoptosis in colon cancer cell via JAK2/STAT3 signalling pathway. The miRNAs are used for the treatment of cancer as essential modulators in cellular pathways. Therefore, identifying the miRNAs and their targets and countering them with specific phytochemicals provide a safe and effective mechanism for the treatment of cancer.


Assuntos
Curcumina , Dieta , MicroRNAs , Neoplasias , Curcumina/farmacologia , Feminino , Humanos , MicroRNAs/genética , Recidiva Local de Neoplasia , Neoplasias/tratamento farmacológico , Neoplasias/genética , Compostos Fitoquímicos/farmacologia , Transdução de Sinais
11.
Saudi J Biol Sci ; 27(11): 2929-2935, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33100848

RESUMO

Plants polysaccharides are an infinite stock of drug composites with varying pharmacological and biological activities. The present investigation aimed to examine the antibacterial, anti-scavenging and cytotoxic potential of garden cress (GC) polysaccharides. The antibacterial effects vs Escherichia coli and as well as Staphylococcus aureus of GC polysaccharides were examined by means of agar diffusion assay, minimum inhibitory concentration (MIC), outer and inner cell membrane permeability. Antioxidant potential of the GC polysaccharides were performed by free radical DPPH scavenging, superoxide anion scavenging, hydroxyl radical scavenging, reducing power potential assay, and hydrogen peroxide method. Cytotoxicity potential of GC polysaccharides were evaluated by MTT assay in human cervical (HeLa) and liver carcinoma (HepG2) cell lines. The findings showed that GC polysaccharides MIC were 1.06 and 0.56 mg mL-1 against E. coli and S. aureus, respectively. Compared to the standard inhibitor, the GC polysaccharides showed essential inhibitor assays in a very dose dependent approach, and notable actions to scavenge reactive oxygen species (ROS) are also due to the large quantities of hydrophilic polyphenols. The IC50 values of all tested parameters were measured against standard ascorbic acid antioxidant agent. The GC polysaccharides diminish the cell viability percentage of HeLa and HepG2 in a concentration dependent manner. GC polysaccharides at a dose of 500 µg ml-1 exhibited higher anti-tumor activity in both HeLa (65.33 ± 3.75%) and HepG2 (60.33 ± 3.48%). The findings obtained in this study indicate that GC polysaccharides has antibacterial and has a possible source of natural antioxidant and also has cytotoxic effect on different carcinoma cell lines.

12.
Oncogene ; 39(6): 1246-1259, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31616062

RESUMO

Germline mutations of DNA double-strand break (DSB) response and repair genes that drive tumorigenesis could be a major cause of prostate cancer (PCa) heritability. In this study, we demonstrated the role of novel exonuclease 5 (EXO5) gene in androgen-induced double strand breaks repair via homology-directed repair pathway and prostate tumorigenesis. Using whole-exome sequencing of samples from 20 PCa families, with three or more siblings diagnosed with metastatic PCa, we identified mutations in 31 genes involved in DSB response and repair. Among them, the L151P mutation in the exonuclease 5 (EXO5) gene was present in all affected siblings in three PCa families. We found two other EXO5 SNPs significantly associated with risk of PCa in cases-controls study from databases of genotype and phenotype (dbGaP), which are in linkage disequilibrium (D' = 1) with Exo5 L151P found in PCa family. The L151 residue is conserved across diverse species and its mutation is deleterious for protein functions, as demonstrated by our bioinformatics analyses. The L151P mutation impairs the DNA repair function of EXO5 due to loss of nuclease activity, as well as failure of nuclear localization. CRISPR elimination of EXO5 in a PCa cell line impaired homology-directed recombination repair (HDR) and caused androgen-induced genomic instability, as indicated by frequent occurrence of the oncogenic fusion transcript TMPRSS2-ERG. Genetic and functional validation of the EXO5 mutations indicated that EXO5 is a risk gene for prostate tumorigenesis, likely due to its functions in HDR.


Assuntos
Androgênios/efeitos adversos , Carcinogênese/patologia , Reparo do DNA , Exonucleases/deficiência , Instabilidade Genômica , Neoplasias Hormônio-Dependentes/patologia , Neoplasias da Próstata/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinogênese/efeitos dos fármacos , Carcinogênese/genética , Estudos de Casos e Controles , Quebras de DNA de Cadeia Dupla , Exonucleases/genética , Exonucleases/metabolismo , Seguimentos , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Humanos , Masculino , Mutação , Neoplasias Hormônio-Dependentes/induzido quimicamente , Neoplasias Hormônio-Dependentes/genética , Proteínas de Fusão Oncogênica/genética , Proteínas de Fusão Oncogênica/metabolismo , Prognóstico , Neoplasias da Próstata/induzido quimicamente , Neoplasias da Próstata/genética
13.
Cell Rep ; 23(2): 389-403, 2018 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-29641999

RESUMO

The arginine methylation status of histones dynamically changes during many cellular processes, including hematopoietic stem/progenitor cell (HSPC) development. The arginine methyltransferases and the readers that transduce the histone codes have been defined. However, whether arginine demethylation actively occurs in cells and what enzyme demethylates the methylarginine residues during various cellular processes are unknown. We report that JMJD1B, previously identified as a lysine demethylase for H3K9me2, mediates arginine demethylation of H4R3me2s and its intermediate, H4R3me1. We show that demethylation of H4R3me2s and H3K9me2s in promoter regions is correlated with active gene expression. Furthermore, knockout of JMJD1B blocks demethylation of H4R3me2s and/or H3K9me2 at distinct clusters of genes and impairs the activation of genes important for HSPC differentiation and development. Consequently, JMJD1B-/- mice show defects in hematopoiesis. Altogether, our study demonstrates that demethylase-mediated active arginine demethylation process exists in eukaryotes and that JMJD1B demethylates both H4R3me2s and H3K9me2 for epigenetic programming during hematopoiesis.


Assuntos
Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Animais , Desmetilação , Epigênese Genética , Feminino , Células HEK293 , Hematopoese , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/metabolismo , Histonas/química , Humanos , Histona Desmetilases com o Domínio Jumonji/antagonistas & inibidores , Histona Desmetilases com o Domínio Jumonji/deficiência , Histona Desmetilases com o Domínio Jumonji/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas , Proteína-Arginina N-Metiltransferases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Especificidade por Substrato
14.
EMBO J ; 34(13): 1829-43, 2015 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-25921062

RESUMO

During nuclear DNA replication, proofreading-deficient DNA polymerase α (Pol α) initiates Okazaki fragment synthesis with lower fidelity than bulk replication by proofreading-proficient Pol δ or Pol ε. Here, we provide evidence that the exonuclease activity of mammalian flap endonuclease (FEN1) excises Pol α replication errors in a MutSα-dependent, MutLα-independent mismatch repair process we call Pol α-segment error editing (AEE). We show that MSH2 interacts with FEN1 and facilitates its nuclease activity to remove mismatches near the 5' ends of DNA substrates. Mouse cells and mice encoding FEN1 mutations display AEE deficiency, a strong mutator phenotype, enhanced cellular transformation, and increased cancer susceptibility. The results identify a novel role for FEN1 in a specialized mismatch repair pathway and a new cancer etiological mechanism.


Assuntos
Reparo de Erro de Pareamento de DNA , DNA Polimerase I/metabolismo , DNA/metabolismo , Endonucleases Flap/metabolismo , Proteína MutS de Ligação de DNA com Erro de Pareamento/metabolismo , Animais , Células Cultivadas , Reparo de Erro de Pareamento de DNA/genética , Replicação do DNA/genética , Embrião de Mamíferos , Feminino , Endonucleases Flap/classificação , Endonucleases Flap/genética , Células HEK293 , Células HeLa , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Proteína MutS de Ligação de DNA com Erro de Pareamento/genética , Saccharomyces cerevisiae
15.
Int J Biol Sci ; 10(8): 834-45, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25076860

RESUMO

Genuine racial differences in prostate cancer (PCa) biology have been considered among the potential reasons to explain PCa disparities. There is no animal model to represent all aspects of human PCa and, more specifically, to be used for PCa disparity research. The lack of a spontaneously transformed in vitro cell-based model system has been a significant impediment to investigating and understanding potential molecular mechanisms, and the hormonal, genetic, and epigenetic factors underlying the biological and clinical aggressiveness of PCa in African American (AA) men. In this study, we established and characterized the E006AA-hT cell line as a highly tumorigenic subline of the previously characterized primary AA-PCa cell line, E006AA. Extensive characterization of the E006AA-hT cell line was accomplished using cytodifferentiation and prostate-specific markers, spectral karyotyping, cell line authentication assays, cell proliferation and migration assays, and in vitro tumorigenesis assays. Spectral karyotyping of E006AA-hT showed a hypertriploid chromosome complement and shared cytogenetic changes similar to its parental cells such as diploid X, absence of Y-chromosomes, numerical gains in chromosomes 5,6,8,10,17,20,21, and marker chromosomes of unknown origin. In addition, E006AA-hT also presented numerous clonal and structural aberrations such as insertion, deletion, duplication, and translocations in chromosomes 1-5, 8, 9, 11, 13, 14, 17, and 18. The E006AA-hT cell line was shown to be highly tumorigenic and produced tumors at an accelerated growth rate in both athymic nude and triple-deficient SCID mice. Silencing the mutated androgen receptor (AR-599 Ser>Gly) did not affect proliferation (loss-of-function), but decreased migration (gain-of-function) in E006AA-hT and its parental cell type. These data support that AR-point mutations may lead simultaneously to different "loss-of-function" and "gain-of-function" phenotypes in PCa cells. E006AA-Par and its subline as the only available spontaneously transformed low- and highly-tumorigenic primary AA-PCa cell lines could be used for basic and translational research aimed in supporting prostate cancer disparity research.


Assuntos
Neoplasias da Próstata/metabolismo , Negro ou Afro-Americano , Linhagem Celular Tumoral , Humanos , Masculino , Receptores Androgênicos/metabolismo
16.
PLoS One ; 9(7): e103204, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25062106

RESUMO

Metabotropic glutamate receptor 1 (GRM1) signaling has been implicated in benign and malignant disorders including prostate cancer (PCa). To further explore the role of genetic alterations of GRM1 in PCa, we screened the entire human GRM1 gene including coding sequence, exon-intron junctions, and flanking untranslated regions (UTRs) for the presence of mutations and single nucleotide polymorphisms (SNPs) in several PCa cell lines and matched tumor-normal tissues from Caucasian Americans (CAs) and African Americans (AAs). We used bidirectional sequencing, allele-specific PCR, and bioinformatics to identify the genetic changes in GRM1 and to predict their functional role. A novel missense mutation identified at C1744T (582 Pro > Ser) position of GRM1 gene in a primary AA-PCa cell line (E006AA) was predicted to affect the protein stability and functions. Another novel mutation identified at exon-intron junction of exon-8 in C4-2B cell line resulted in alteration of the GRM1 splicing donor site. In addition, we found missense SNP at T2977C (993 Ser > Pro) position and multiple non-coding mutations and SNPs in 3'-UTR of GRM1 gene in PCa cell lines and tissues. These novel mutations may contribute to the disease by alterations in GRM1 gene splicing, receptor activation, and post-receptor downstream signaling.


Assuntos
Polimorfismo de Nucleotídeo Único/genética , Neoplasias da Próstata/genética , Receptores de Glutamato Metabotrópico/genética , Negro ou Afro-Americano/genética , Alelos , Linhagem Celular Tumoral , Células Epiteliais/metabolismo , Éxons/genética , Genótipo , Humanos , Íntrons/genética , Masculino , Mutação de Sentido Incorreto/genética , Neoplasias da Próstata/patologia , Regiões não Traduzidas/genética , População Branca/genética
17.
BMJ Open ; 4(2): e004239, 2014 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-24578538

RESUMO

OBJECTIVES: Cytokines and related molecules in immune-response pathways seem important in deciding the outcome of the host-pathogen interactions towards different polar forms in leprosy. We studied the role of significant and functionally important single-nucleotide polymorphisms (SNPs) in these genes, published independently from our research group, through combined interaction with an additional analysis of the in silico network outcome, to understand how these impact the susceptibility towards the disease, leprosy. DESIGN: The study was designed to assess an overall combined contribution of significantly associated individual SNPs to reflect on epistatic interactions and their outcome in the form of the disease, leprosy. Furthermore, in silico approach was adopted to carry out protein-protein interaction study between PARK2 and proinflammatory/anti-inflammatory cytokines. SETTING: Population-based case-control study involved the data of North India. Protein-protein interaction networks were constructed using cytoscape. PARTICIPANTS: Study included the data available from 2305 Northern Indians samples (829 patients with leprosy; 1476 healthy controls), generated by our research group. PRIMARY AND SECONDARY OUTCOME MEASURES: For genotype interaction analysis, all possible genotype combinations between selected SNPs were used as an independent variable, using binary logistic regression with the forward likelihood ratio method, keeping the gender as a covariate. RESULTS: Interaction analysis between PARK2 and significant SNPs of anti-inflammatory/proinflammatory cytokine genes, including BAT1 to BTNL2-DR spanning the HLA (6p21.3) region in a case-control comparison, showed that the combined analysis of: (1) PARK2, tumour necrosis factor (TNF), BTNL2-DR, interleukin (IL)-10, IL-6 and TGFBR2 increased the risk towards leprosy (OR=2.54); (2) PARK2, BAT1, NFKBIL1, LTA, TNF-LTB, IL12B and IL10RB provided increased protection (OR=0.26) in comparison with their individual contribution. CONCLUSIONS: Epistatic SNP-SNP interactions involving PARK2 and cytokine genes provide an additive risk towards leprosy susceptibility. Furthermore, in silico protein-protein interaction of PARK2 and important proinflammatory/anti-inflammatory molecules indicate that PARK2 is central to immune regulation, regulating the production of different cytokines on infection.


Assuntos
Citocinas/genética , Hanseníase/genética , Polimorfismo de Nucleotídeo Único , Ubiquitina-Proteína Ligases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Criança , Epistasia Genética , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Índia , Masculino , Pessoa de Meia-Idade
18.
Hum Genet ; 131(5): 703-16, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22071774

RESUMO

Host immune response against Mycobacterium leprae plays an important role in providing resistance to infection and disease progression. Genome-wide linkage and association studies suggest the possibility of multiple risk loci within HLA (6p21.3) region. Any systematic study of relevance within the histocompatibility complex of importance in host immune response would be pertinent because of non-replication of the known loci and unavailable information on some of the unexplored genes and regions. A systematic scan was performed of the selected region involving LTA-TNF-LTB genes within 6p21.3 with a resolution of 1SNP/127 bp; and the SNPs in flanking BAT1, NFKBIL and BTNL2-DRA genes on the basis of their tag status or their presence in promoter/exonic regions with MAF of >5%. Nine SNPs located in BAT1, LTA, TNF genes and BTNL2-DRA interval showed strong association with leprosy susceptibility in two independent sets of North Indian population which was replicated in a geographically distinct East Indian population. Conditional logistic regression showed at least one functional SNP remaining significant in each gene, suggesting an independent role of each of the disease associated SNPs. In vitro reporter assay revealed that two SNPs located at BAT1 promoter and 13 kb upstream to LTA gene affected the transcription factor binding site, hence the gene expression. We unravel the role of unexplored immunologically important genes, BAT1 and BTNL2, in addition to known LTA and TNF genes, and the haplotypes of the significantly associated SNPs therein, to understand susceptibility to the disease, leprosy and its differential severity.


Assuntos
Cromossomos Humanos Par 6 , Predisposição Genética para Doença , Hanseníase/genética , Complexo Principal de Histocompatibilidade/genética , Polimorfismo de Nucleotídeo Único , Povo Asiático/genética , Evolução Biológica , Butirofilinas , RNA Helicases DEAD-box/genética , Haplótipos , Humanos , Índia , Linfotoxina-alfa/genética , Glicoproteínas de Membrana/genética , Fator de Necrose Tumoral alfa/genética
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