RESUMO
A library of benzimidazole briged pyrazolo[1,5-a]pyrimidine (6a-q) was designed, synthesized and subjected for evaluation for cytotoxic potential. Antiproliferative activity, ranging from 3.1-51.5 µM, was observed against a panel of cancer cell lines which included MCF-7 (breast cancer), A549 (lung cancer), HeLa (cervical cancer) and SiHa (cervical cancer). Among them, 6k, 6l, 6n and 6o have shown significant cytotoxicity and were investigated further to study their probable mechanism of action against MCF-7 cell line. Accumulation of cells at sub-G1 phase was observed in flow cytometric analysis. The detachment of cells from substratum and membrane blebbing seen under bright field microscopy supports the ability of these conjugates to induce apoptosis. Immunostaining and western blot analysis showed EGFR, p-EGFR, STAT3, and p-STAT3 significant downregulation. Western blot analysis demonstrated an elevated level of apoptotic proteins such as p53, p21, Bax, whereas a decrease in the antiapoptotic protein Bcl-2 and procaspase-9, confirming the ability of these conjugates to trigger cell death by apoptosis. EGFR kinase assay confirms the specific activity of conjugates. Molecular docking simulation study disclosed that these molecules fit well in ATP-binding pocket of EGFR. The analysis of docking poses and the atomic interactions of different conjugates rationalize the structural-activity relationship in this series. Benzimidazole-linked pyrazolo[1,5-a]pyrimidine conjugates were synthesized and evaluated for their anticancer potential. All the conjugates have significant anticancer potential. Further mechanistic studies revealed that these conjugates arrest cancer cell growth by EGFR/STAT3 inhibition.
Assuntos
Antineoplásicos , Neoplasias do Colo do Útero , Feminino , Humanos , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular , Antineoplásicos/farmacologia , Antineoplásicos/química , Receptores ErbB , Apoptose , Pirimidinas/farmacologia , Pirimidinas/química , Benzimidazóis/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Proliferação de Células , Relação Estrutura-Atividade , Estrutura MolecularRESUMO
The cancer-testis antigen CTCFL/BORIS (Brother of Regulator of Imprinted Sites) also known, as a paralog of CTCF -the "master weaver of the genome" is a key transcriptional regulator. Both CTCF and BORIS can bind to the same promoter sequence and recruit diverse proteins. BORIS is also known to be associated with actively translating ribosomes suggesting new roles of BORIS in gene expression. Various studies have attempted to elucidate the role of BORIS in different cell types for the development of targeted therapy depending on molecular signatures and genetic aberrations associated with the disease type. The current study is focused on its role in neuroblastoma. Here, we have deciphered the role of BORIS on TGFß1 pathway which is highly affected by embryonic CTCFL expression. BORIS stabilized the SMAD3 and SMAD4 transcripts leading to prolonged TGFß activation. Further, loss of BORIS abrogated both the canonical and non-canonical TGFß signaling suggesting the dependency of TGFß on BORIS. The effect on the metabolic profile of the neuroblastoma cells were analyzed with change in BORIS expression levels. Also, ectopic expression of BORIS leads to Drp1 phosphorylation (Ser616) enhancing mitochondrial fission followed by a switch in cellular metabolism towards glycolysis. This cellular metabolism switch was in turn supported with a reduction in oxygen consumption rate upon BORIS expression. Interestingly methylome analysis revealed patterns of global histone methylation, a mechanism that regulate important signaling pathways in neuroblastoma. This study analyzes the consequence of BORIS expression in neuroblastoma cells and thereby elucidate its downstream targets, which could help in designing effective therapeutic for treating neuroblastoma. Similar results were obtained in both MYCN amplified and non-MYCN neuroblastoma cell lines, indicating a common mechanism of BORIS/CTCFL action in neuroblastoma.
Assuntos
Proteínas de Ligação a DNA , Dinaminas , Neuroblastoma , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Dinâmica Mitocondrial , Neuroblastoma/genética , Fator de Crescimento Transformador beta/genéticaRESUMO
In present study, a new series of 4, 7-disubstituted coumarin derivatives (7a-y) have been synthesized as galectin-1 targeting apoptosis inducing agents and evaluated for their in vitro cytotoxic potentials against a panel of selected human cancer cell lines namely, Brest (MCF7), Ovarian (SKOV3), Prostate (PC-3 & DU145) and normal embryonic kidney (HEK293T) cells, using MTT assay. Most of the compounds exhibited potent growth inhibitory action against the treated cancer cell lines with an IC50 range of 10-30 µM. Compound 7q exhibited a significant growth inhibition against prostate cancer (PC-3 & DU145) cell lines with an IC50 value of 7.45 ± 0.03 µM, 8.95 ± 0.17 µM respectively. Further, the target compound 7q was radiolabeled with fluorine-18 [18F] to be used as a novel PET radiotracer for imaging of tumors via targeting galectin-1, using appropriate reaction conditions in the GE Tracer-lab FX2N synthesis module. The purification of the [18F] radiolabeled compound [18F]-7q was successfully achieved with 60% ethanol. The radiochemical purity was>85% and residual solvent limits of DMF was 65 ± 3 ppm as analysed by HPLC, TLC & GC analytical methods. The apoptosis studies confirm the inhibition of cell proliferation with morphological changes like cell shrinkage, blebbing and cell wall deformation, increasing the ROS levels, and loss of mitochondrial membrane potential by Acridine orange/Ethidium bromide staining, Hoechst-33342 staining, H2DCFDA staining, annexin V-FITC/PI, and JC-1 staining methods. In flow cytometric analysis, 7q selectively arrested the sub-G1 phase of the cell cycle in a dose-dependent manner. In Gal-1 ELISA studies, compound 7q efficiently reduced the levels of Gal-1 protein in dose-dependent manner with an IC50 value of 100 µM. The binding constant (Ka) of 7q with Gal-1 was observed as 1.3 × 104 M-1 by fluorescence spectroscopy. The molecular docking studies clearly showed possible interactions and the pharmacokinetic (ADMET) properties of compound 7q with Gal-1. Hence, the novel 4, 7-disubstituted coumarins could be a potential cytotoxic and PET imaging agents via Gal-1.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Cumarínicos/química , Cumarínicos/farmacologia , Antineoplásicos/síntese química , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cumarínicos/síntese química , Ensaios de Seleção de Medicamentos Antitumorais , Radioisótopos de Flúor/química , Galectina 1/metabolismo , Células HEK293 , Humanos , Modelos Moleculares , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Tomografia por Emissão de PósitronsRESUMO
In an attempt to develop potent and selective anticancer agents, a series of 15 conjugates of 1,4-dihydroindeno[1,2-c]pyrazole chalcone (12a-o) were designed, synthesized and evaluated for their antiproliferative activity against MCF7, A549, MDA-MB-231, HCT116 and SKBR3 human cancer cell lines. Among them, 12h, 12l and 12m showed IC50 values: 3.82, 5.33 and 4.21⯵M, respectively, on A549â¯cell with respect to the positive control, Erlotinib (IC50 value: 10.26⯵M). Detailed biological assays showed accumulation of mitotic cells in G2/M phase. In addition, Western blot analysis and immunofluorescence study revealed inhibition of EGFR and Akt pathways. In silico computational studies were also carried out to predict the binding modes and pharmacokinetic parameters of these conjugates.
Assuntos
Chalconas/farmacocinética , Desenho de Fármacos , Proteína Oncogênica v-akt/antagonistas & inibidores , Células A549 , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Simulação por Computador , Receptores ErbB/antagonistas & inibidores , Receptores ErbB/metabolismo , Humanos , Concentração Inibidora 50 , Proteína Oncogênica v-akt/metabolismo , Pirazóis/farmacocinéticaRESUMO
Polycomb group (PcG) proteinB lymphoma Mo-MLV insertion region 1 homolog (BMI1) is a transcriptional repressor that plays an important role in human carcinogenesis. MicroRNAs (miRNAs) are endogenous small non-coding RNAsthat implicate a negative regulation on gene expression. Deregulation of the expression of miRNAs has been implicated in tumorigenesis. Here, we have shown that knock-down ofBMI1increases theexpression of tumor-suppressivemiRNAs. Elevated levels of expression of miR-200a, miR-200b, miR-15a, miR-429, miR-203were observed upon knock-down of BMI1. Up-regulation of these miRNAsleads to down-regulation ofPRC1 group of proteins i.e. BMI1, RING1A, RING1B and Ub-H2A. Interestingly, overexpression of miR-200a, miR-200b and miR-15aalso produced decreased BMI1 and Ub-H2A protein expression in the CD44+ Cancer Stem Cellpopulation of MDAMB-231cells. Also,elevating the levels of BMI1 regulated miRNAspromoted Mesenchymal to Epithelial transition by regulating the expression of N-Cadherin, Vimentin, ß-Catenin, Zeb, Snail thereby resulting in decreased invasion, migration and proliferation. Here, we also report that miR-200a, miR-200b, miR-203 accretes the sensitivity of MDAMB-231 cells to the histone deacetylase inhibitor (HDACi) SAHA and miR-15a sensitized breast cancer cells to the chemotherapeutic drug cisplatin leading to apoptosis. These findings suggest that modulatingspecific miRNAs may serve as a therapeutic approach for the treatment of breast cancer.
Assuntos
Neoplasias da Mama/patologia , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Complexo Repressor Polycomb 1/genética , Regiões 3' não Traduzidas , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Invasividade Neoplásica , Metástase NeoplásicaRESUMO
Argonaute family proteins are well conserved among all organisms. Its role in mitotic cell cycle progression and apoptotic cell elimination is poorly understood. Earlier we have established the contribution of Ago-1 in cell cycle control related to G2/M cyclin in Drosophila. Here we have extended our study in understanding the relationship of Ago-1 in regulating apoptosis during Drosophila development. Apoptosis play a critical role in controlling organ shape and size during development of multi cellular organism. Multifarious regulatory pathways control apoptosis during development among which highly conserved JNK (c-Jun N-terminal kinase) pathway play a crucial role. Here we have over expressed Ago-1 in Drosophila eye and brain by employing UAS (upstream activation sequence)-GAL4 system under the expression of eye and brain specific driver. Over expression of Ago-1 resulted in reduced number of ommatidia in the eye and produced smaller size brain in adult and larval Drosophila. A drastic reversal of the phenotype towards normal was observed upon introduction of a single copy of the dominant negative mutation of basket (bsk, Drosophila homolog of JNK) indicating an active and physical involvement of the bsk with Ago-1 in inducing developmental apoptotic process. Further study showed that Ago-1 stimulates phosphorylation of JNK through transforming growth factor-ß activated kinase 1- hemipterous (Tak1-hep) axis of JNK pathway. JNK phosphorylation results in up regulation of pro-apoptotic genes head involution defective (hid), grim & reaper (rpr) and induces activation of Drosophila caspases (cysteinyl aspartate proteinases);DRONC (Death regulator Nedd2-like caspase), ICE (alternatively Drice, Death related ICE-like caspase) and DCP1 (Death caspase-1) by inhibiting apoptotic inhibitor protein DIAP1 (Death-associated inhibitor of apoptosis 1). Further, Ago-1 also inhibits miR-14 expression to trigger apoptosis. Our findings propose that Ago-1 acts as a key regulator in controlling cell death, tumor regression and stress response in metazoan providing a constructive bridge between RNAi machinery and cell death.
Assuntos
Apoptose/fisiologia , Proteínas Argonautas/genética , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Animais , Encéfalo/citologia , Olho/citologia , MAP Quinase Quinase 4/metabolismo , FosforilaçãoRESUMO
MicroRNAs (miRNAs) are a class of small, non-coding RNAs that are involved in the regulation of gene expression at the post-transcriptional level. MicroRNAs play an important role in cancer cell proliferation, survival and apoptosis. Epigenetic modifiers regulate the microRNA expression. Among the epigenetic players, histone deacetylases (HDACs) function as the key regulators of microRNA expression. Epigenetic machineries such as DNA and histone modifying enzymes and various microRNAs have been identified as the important contributors in cancer initiation and progression. Recent studies have shown that developing innovative microRNA-targeting therapies might improve the human health, specifically against the disease areas of high unmet medical need. Thus microRNA based therapeutics are gaining importance for anti-cancer therapy. Studies on Triple negative breast cancer (TNBC) have revealed the early relapse and poor overall survival of patients which needs immediate therapeutic attention. In this report, we focus the effect of HDAC inhibitors on TNBC cell proliferation, regulation of microRNA gene expression by a series of HDAC genes, chromatin epigenetics, epigenetic remodelling at miR-200 promoter and its modulation by various HDACs. We also discuss the need for identifying novel HDAC inhibitors for modulation of miR-200 in triple negative breast cancer.
Assuntos
Epigênese Genética/efeitos dos fármacos , Epigênese Genética/genética , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/uso terapêutico , MicroRNAs/genética , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Animais , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Epigenômica/métodos , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Histona Desacetilases/metabolismo , HumanosRESUMO
A series of 1, 4-dihydroindeno-[1,2-c] pyrazole linked oxindole conjugates have been synthesized by using Knoevenagel condensation method and further evaluated for their antiproliferative activity against HeLa, A549 and MDA-MB-231 human cancer cell lines along with HEK-293 (normal human embryonic kidney cells). Among the derivatives, compounds 12a, 12b, and 12d showed excellent cytotoxicity with IC50 values ranging between 1.33 to 4.33 µM. Furthermore, detailed biological assays showed that there was accumulation of mitotic cells in G2/M phase, disruption of microtubule network and increase in the G2/M checkpoint proteins (Cyclin B1 and CDK1). Moreover, compound 12d with IC50 value of 1.33 µM showed significant upregulation of tumor suppressor proteins like p53, p21 and pro-apoptotic Bax. The molecular docking analysis demonstrated that these congeners occupy the colchicine binding pocket of the tubulin.
Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Pirazóis/química , Pirazóis/farmacologia , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia , Linhagem Celular Tumoral , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HEK293 , Células HeLa , Humanos , Indóis/química , Indóis/farmacologia , Simulação de Acoplamento Molecular , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Oxindóis , Tubulina (Proteína)/metabolismo , Proteína Supressora de Tumor p53/metabolismoRESUMO
Cancer has been established as the "Emperor of all maladies". In recent years, medicinal chemistry has focused on identifying novel anti-cancer compounds; though discovery of these compounds appears to be a herculean task. In present study, we synthesized forty pyrazolochalcone conjugates and explored their cytotoxic activity against a panel of sixty cancer cell lines. Fifteen conjugates of the series showed excellent growth inhibition (13b-e, 13h-j, 14c-d, 15 a, 15 c-d, 16b, 16d and 18f; GI50 for MCF-7: 0.4-20 µM). Conjugates 13b, 13c, 13d, 16b and 14d were also evaluated for their cytotoxic activity in human breast cancer cell line (MCF-7). The promising candidates induced cell cycle arrest, mitochondrial membrane depolarization and apoptosis in MCF-7 cells at a 2 µM concentration. Furthermore, inhibition of PI3K/Akt/mTOR pathway-regulators such as PI3K, p-PI3K, p-AKT, and mTOR were observed; as well as upregulation of p-GSK3ß and tumor-suppressor protein, PTEN. Our study indicates that pyrazolochalcone conjugates could serve as potential leads in the development of tailored cancer therapeutics.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Chalconas/farmacologia , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Pirazóis/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Chalconas/síntese química , Chalconas/química , Relação Dose-Resposta a Droga , Feminino , Humanos , Células MCF-7 , Estrutura Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Pirazóis/síntese química , Pirazóis/química , Relação Estrutura-Atividade , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismoRESUMO
In recent years, long non-coding RNAs (lncRNAs) have attracted the attention of researchers with their involvement in all facets of life. LncRNAs are transcripts of more than 200 nucleotides which lack defined protein coding potential. Although they do not code for proteins, a large number of them are involved in regulating gene expression and translation. The presence of numerous lncRNAs in the human genome has prompted us to investigate the contribution of these molecules to human biology and medicine. In this review, we present the potential role of lncRNAs interlinked to different human diseases and genetic disorders. We also describe their role in cellular differentiation and aging and discuss their potential importance as biomarkers and as therapeutic agents.
Assuntos
Regulação da Expressão Gênica , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Envelhecimento , Animais , Apoptose , Doenças Autoimunes/diagnóstico , Doenças Autoimunes/metabolismo , Doenças Autoimunes/patologia , Biomarcadores/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/patologia , Diferenciação Celular , Glândulas Endócrinas/metabolismo , Humanos , Imunidade/fisiologia , Camundongos , Neoplasias/diagnóstico , Neoplasias/metabolismo , Neoplasias/patologia , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/patologia , RatosRESUMO
A series of pyrazolo[1,5-a]pyrimidines substituted at C5 with 1-phenylprop-2-en-1-one (6a-q) and 3-phenylprop-2-en-1-one (7a-k) was synthesized and evaluated for antiproliferative activity. Among them, 6h was found to be the most active compound against the MDA-MB-231 cell line with an IC50 of 2.6 µM . The antiproliferative activity of this series of compounds ranged from 2.6 to 34.9 µM against A549 (lung cancer), MDA-MB-231 (breast cancer) and DU-145 (prostate cancer) cell lines. FACS analysis revealed that these hybrids arrest the cell cycle at the subG1 phase. Western blot analysis and an immunofluorescence assay showed the inhibition of the EGFR and STAT3 axis, which plays an important role in cell survival and apoptosis. Western blot and RT-PCR analyses that displayed an increase in apoptotic proteins such as p53, p21 and Bax and a decrease in the anti-apoptotic proteins Bcl-2 and procaspase-9 confirmed the ability of these hybrids to trigger cell death by apoptosis. Molecular docking studies described the binding of these hybrids to the ATP binding site of EGFR.
RESUMO
MicroRNAs (miRNAs) are well preserved in every animal. These pigmy sized non-coding RNAs (21-23 nt), scattered in genome, are responsible for micromanaging the versatile gene regulations. Involvement of miRNAs was surveillance cops in all human diseases including cardiovascular defects, tumor formation, reproductive pathways, and neurological and autoimmune disorders. The effective functional role of miRNA can be reduced by chemical entities of antisense oligonucleotides and versatile small molecules that support the views of novel therapy of different human diseases. In this study, we have updated our current understanding for designing and synthesizing miRNA-controlling therapeutic chemicals. We have also proposed various in-vivo delivery strategies and their ongoing challenges to combat the incorporation hurdles in live cells and animals. Lastly, we have demonstrated the current progress of miRNA modulation in the treatment of different human diseases that provides an alternative approach of gene therapy.
RESUMO
AIMS: Breast cancer is highly resistant to chemotherapeutic approach and hence, alternative strategies have been developed to fight against this heterogeneous group of disease. In particular, many studies have demonstrated about various drugs for the treatment of breast cancer. In our study, we assessed the anti-angiogenenic activities of Bisindole-PBD (5b) in MCF-7 and MDA-MB-231 cell lines. MAIN METHODS: In vitro Endothelial Cell (HUVEC) Tube Formation Assay was performed to show inhibitory role of 5b along with its role upon wound healing process in breast cancer cells in vitro. Semi-quantitative reverse transcription PCR (RT-PCR) was also done to examine the expression of VEGF in response to 5b in breast cancer cells and in HUVEC cells. siRNA transfection study explored STAT3 mediated VEGF transcription in breast cancer cells MCF-7 and MDA-MB-231. CAM assay was performed to see the role of 5b on vessel formation in chicken embryo. KEY FINDINGS: From in vitro data we have demonstrated that 5b played a role in regulation of breast cancer cell proliferation by inhibiting angiogenesis. Test drug 5b suppressed the expression VEGF at both transcriptional and post transcriptional levels. Apart from this, there was significant down regulation in STAT3 level after drug treatment, which was found to be involved in the VEGF transcription. Metastasis related MMP-2 and MMP-9 expressions were also modulated by 5b. In vivo study by Chick Chorioallantoic Membrane (CAM) Assay also showed anti-angiogenesis role of the test drug which was consistent with the in vitro data. SIGNIFICANCE: Altogether, our data demonstrated 5b as potent small molecule with anti-angiogenic activities.
Assuntos
Inibidores da Angiogênese/farmacologia , Dioxinas/farmacologia , Indóis/farmacologia , Neovascularização Patológica/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Regulação para Baixo/efeitos dos fármacos , Feminino , Humanos , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/biossíntese , Neovascularização Patológica/tratamento farmacológico , Cicatrização/efeitos dos fármacosRESUMO
A series of anilinonicotinyl linked pyrazolo[1,5-a]pyrimidine conjugates (6a-x) were synthesized and evaluated for their antiproliferative activity. Some of these conjugates exhibited promising cytotoxic effects in the MCF-7 cell line and among these 6a and 6c exhibited significant effects, apart from G2/M cell cycle arrest. Interestingly they showed profound effects on cyclin D1, Bcl-2 and survivin proteins that regulate breast cancer cell proliferation. Moreover, ER alpha protein expression was studied to understand regulatory role of these conjugates on estrogen activity in estrogen positive breast cancer cells like MCF-7 and compounds 6a and 6c reduced their activity.
Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Estrogênios/metabolismo , Nicotina/análogos & derivados , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Células MCF-7 , Estrutura Molecular , Nicotina/síntese química , Nicotina/química , Nicotina/farmacologia , Pirimidinas/síntese química , Pirimidinas/química , Relação Estrutura-AtividadeRESUMO
In a previous study we reported the role of potent bisindole-PBD conjugate as an inclusion in the arsenal of breast cancer therapeutics. In breast cancer cell proliferation, PI3K/AKT/mTOR pathway plays a crucial role by prosurvival mechanism that inhibits programmed cell death. Here, 2 breast cancer cells lines, MCF-7 and MDA-MB-231 were treated with Vorinostat (suberoylanilide hydroxamic acid / SAHA) and bisindole-PBD (5b). We have investigated the effect on PI3K/AKT/mTOR pathway and SIRT expression including epigenetic regulation. There was consistent decrease in the level of PI3K, AKT, mTOR proteins upon treatment of 5b in both MCF-7 and MDA-MB-231 cell lines compared to untreated controls. Treatment with caspase inhibitor (Q-VD-OPH) confirmed that the effect of 5b on PI3K signaling was ahead of apoptosis. Real time PCR and western blot analysis showed profound reduction in the mRNA and protein levels of SIRT1 and SIRT2. Molecular docking studies also supported the interaction of 5b with various amino acids of SIRT2 proteins. Treatment with 5b caused epigenetic changes that include increase of acetylated forms of p53, increase of histone acetylation at p21 promoter as well as decrease in methylation state of p21 gene. Compound 5b thus acts as SIRT inhibitor and cause p53 activation via inhibition of growth factor signaling and activation of p53 dependent apoptotic signaling. This present study focuses bisindole-PBD on epigenetic alteration putting 5b as a promising therapeutic tool in the realm of breast cancer research.
Assuntos
Neoplasias da Mama/genética , Sirtuína 1/genética , Sirtuína 1/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Neoplasias da Mama/metabolismo , Proliferação de Células , Feminino , HumanosRESUMO
Diverse array of therapeutic regimens, drugs or siRNA, are commonly used to regress cardiac hypertrophy, although, bystander effect and lower retention of bioactive molecules significantly reduce their functional clinical efficacy. Carvedilol, a widely used and effective anti-hypertrophic drug, simultaneously blocks ß-adrenergic receptors non-specifically in various organs. Likewise, non-specific genome-wide downregulation of p53 expression by specific siRNA efficiently abrogates cardiac hypertrophy but results in extensive tumorigenesis affecting bystander organs. Therefore, delivery of such therapeutics had been a challenge in treating cardiovascular dysfunction. Cardiac tissue engineering was successfully accomplished in this study, by encapsulating such bioactive molecules with a stearic acid modified Carboxymethyl chitosan (CMC) nanopolymer conjugated to a homing peptide for delivery to hypertrophied cardiomyocytes in vivo. The peptide precisely targeted cardiomyocytes while CMC served as the vector mediator to pathological myocardium. Controlled delivery of active therapeutic payloads within cardiomyocytes resulted in effective regression of cardiac hypertrophy. Thus, this novel nano-construct as a spatio-temporal vector would be a potential tool for developing effective therapeutic strategies within cardiac micro-environment via targeted knockdown of causal genes.
Assuntos
Carbazóis/administração & dosagem , Cardiomegalia/tratamento farmacológico , Cardiotônicos/administração & dosagem , Quitosana/administração & dosagem , Peptídeos/administração & dosagem , Propanolaminas/administração & dosagem , RNA Interferente Pequeno/administração & dosagem , Animais , Efeito Espectador , Carbazóis/química , Cardiomegalia/genética , Cardiotônicos/química , Carvedilol , Células Cultivadas , Quitosana/análogos & derivados , Quitosana/química , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Humanos , Miócitos Cardíacos , Nanopartículas/administração & dosagem , Nanopartículas/química , Peptídeos/química , Propanolaminas/química , RNA Interferente Pequeno/química , Ratos Wistar , Ácidos Esteáricos/química , Engenharia Tecidual , Proteína Supressora de Tumor p53/genéticaRESUMO
Glioma amplified sequence41 (Gas41) is a highly conserved putative transcription factor that is frequently abundant in human gliomas. Gas41 shows oncogenic activity by promoting cell growth and viability. In the present study, we show that Gas41 is required for proper functioning of RNA interference (RNAi) machinery in the nuclei, although three basic structural domains of RNAi components PAZ, PIWI and dsRNA with respect to binding are absent in the structural sequences. Variations of structural domains are highly conserved among prokaryotes and eukaryotes. Gas41 interacts with cytological RNase III enzyme Dicer1 both biochemically and genetically. However, Drosophila Gas41 functions as chromatin remodeler and interacts with different heterochromatin markers and repeat-induced transgene silencing by modulating position effect variegation. We also show that transcriptional inactive Gas41 mutant interferes with the functional assembly of heterochromatin-associated proteins, dimethylated lysine 9 of histone H3 and heterochromatic protein 1 in developing embryos. A reduction of heterochromatic markers is accompanied by the mini-w promoter sequence in Gas41 mutants. These findings suggest that Drosophila Gas41 guides the repeat associated gene silencing and the Dicer1 interaction, thereby depicting a new role for Gas41. Gas41 is a critical RNAi component. In Drosophila, Gas41 plays a dual role. On the one hand, it appears to participate with Dicer 1 in the RNAi pathway and, alternatively, it also participates in repeat-induced gene silencing by accumulating heterochromatin proteins at the mini-w array promoters. Therefore, it represents an intriguing and apparently paradoxical new finding in RNA technology with respect to the process of heterochromatin gene silencing.
Assuntos
Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Genes de Insetos , Heterocromatina/genética , Heterocromatina/metabolismo , Fosfoenolpiruvato Carboxiquinase (ATP)/genética , Fosfoenolpiruvato Carboxiquinase (ATP)/metabolismo , Interferência de RNA , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Elementos de DNA Transponíveis , Proteínas de Drosophila/imunologia , Drosophila melanogaster/embriologia , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Masculino , Dados de Sequência Molecular , Mutação , Oncogenes , Fosfoenolpiruvato Carboxiquinase (ATP)/imunologia , RNA Helicases/genética , RNA Helicases/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ribonuclease III/genética , Ribonuclease III/metabolismo , Homologia de Sequência de AminoácidosRESUMO
Nanoparticles, such as gold nanoparticles (GNP), upon convenient modifications perform multi tasks catering to many biomedical applications. However, GNP or any other type of nanoparticles is yet to achieve the feat of intracellular regulation of endogenous genes of choice such as through manipulation of a gene-promoter in a chromosome. As for gene modulation and delivery, GNP (or other nanoparticles) showed only limited gene therapy potential, which relied on the delivery of 'exogenous' genes invoking gene knockdown or replacement. Practically, there are no instances for the nanoparticle-mediated promoter regulation of 'endogenous' genes, more so, as a cancer selective phenomenon. In this regard, we report the development of a simple, easily modifiable GNP-formulation, which promoted/up-regulated the expression of a specific category of 'endogenous' genes, the glucocorticoid responsive genes. This genetic up-regulation was induced in only cancer cells by modified GNP-mediated transcriptional activation of its cytoplasmic receptor, glucocorticoid receptor (GR). Normal cells and their GR remained primarily unperturbed by this GNP-formulation. The most potent gene up-regulating GNP-formulation down-regulated a cancer-specific proliferative signal, phospho-Akt in cancer cells, which accompanied retardation of tumor growth in the murine melanoma model. We show that GR-targeted GNPs may find potential use in the targeting and modulation of genetic information in cancer towards developing novel anticancer therapeutics.
Assuntos
Dexametasona/administração & dosagem , Nanopartículas Metálicas/química , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/genética , Regiões Promotoras Genéticas/genética , Receptores de Glucocorticoides/genética , Animais , Antineoplásicos Hormonais/administração & dosagem , Antineoplásicos Hormonais/química , Linhagem Celular Tumoral , Dexametasona/química , Difusão , Marcação de Genes/métodos , Ouro/química , Humanos , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/ultraestrutura , Camundongos , Nanocápsulas/administração & dosagem , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Neoplasias Experimentais/patologia , Resultado do TratamentoRESUMO
BACKGROUND: Cardiovascular complication due to diabetes has remained a major cause of death. There is an urgent need to intervene the cardiac complications in diabetes by nutritional or pharmacological agents. Thus the present study was designed to find out the effectiveness of garlic on cardiac complications in insulin-resistant diabetic rats. METHODS AND RESULTS: SD rats were fed high fructose (65%) diet alone or along with raw garlic homogenate (250 mg/kg/day) or nutrient-matched (65% corn starch) control diet for 8 weeks. Fructose-fed diabetic rats showed cardiac hypertrophy, increased NFkB activity and increased oxidative stress. Administration of garlic significantly decreased (p<0.05) cardiac hypertrophy, NFkB activity and oxidative stress. Although we did not observe any changes in myocardial catalase, GSH and GPx in diabetic heart, garlic administration showed significant (p<0.05) increase in all three antioxidant/enzymes levels. Increased endogenous antioxidant enzymes and gene expression in garlic treated diabetic heart are associated with higher protein expression of Nrf2. Increased myocardial H2S levels, activation of PI3K/Akt pathway and decreased Keap levels in fructose-fed heart after garlic administration might be responsible for higher Nrf2 levels. CONCLUSION: Our study demonstrates that raw garlic homogenate is effective in reducing cardiac hypertrophy and fructose-induced myocardial oxidative stress through PI3K/AKT/Nrf2-Keap1 dependent pathway.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas do Citoesqueleto/metabolismo , Diabetes Mellitus Experimental/metabolismo , Frutose/efeitos adversos , Alho , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Edulcorantes/efeitos adversos , Animais , Cardiomegalia/etiologia , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Diabetes Mellitus Experimental/patologia , Frutose/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch , Masculino , Miocárdio/metabolismo , Miocárdio/patologia , Ratos , Ratos Sprague-Dawley , Edulcorantes/farmacologiaRESUMO
By applying a methodology, a series of benzothiazole-pyrrole based conjugates (4a-r) were synthesized and evaluated for their antiproliferative activity. Compounds such as 4a, 4c, 4e, 4g-j, 4m, 4n, 4o and 4r exhibited significant cytotoxic effect in the MCF-7 cell line. Cell cycle effects were examined for these conjugates at 2 µM as well as 4 µM concentrations and FACS analysis show an increase of G2/M phase cells with concomitant decrease of G1 phase cells thereby indicating G2/M cell cycle arrest by them. Interestingly 4o and 4r are effective in causing apoptosis in MCF-7 cells. Moreover, 4o showed down regulation of oncogenic expression of Ras and its downstream effector molecules such as MEK1, ERK1/2, p38 MAPK and VEGF. The apoptotic aspect of this conjugate is further evidenced by increased expression of caspase-9 in MCF-7 cells. Hence these small molecules have the potential to control both the cell proliferation as well as the invasion process in the highly malignant breast cancers.