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1.
Cells ; 12(2)2023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36672152

RESUMO

Osteoporosis is a systemic skeletal disease characterised by low bone mineral density (BMD), degeneration of bone micro-architecture, and impaired bone strength. Cissus quadrangularis (CQ), popularly known as Hadjod (bone setter) in Hindi, is a traditional medicinal herb exhibiting osteoprotective potential in various bone diseases, especially osteoporosis and fractures. However, the cellular mechanisms underpinning its direct effect on bone health through altering the host immune system have never been elucidated. In the present study, we interrogated the osteoprotective and immunoporotic (the osteoprotective potential of CQ via modulating the host immune system) potential of CQ in preventing inflammatory bone loss under oestrogen-deficient conditions. The current study outlines the CQ's osteoprotective potential under both ex vivo and in vivo (ovariectomized) conditions. Our ex vivo data demonstrated that, in a dose-dependent manner CQ, suppresses the RANKL-induced osteoclastogenesis (p < 0.001) as well as inhibiting the osteoclast functional activity (p < 0.001) in mouse bone marrow cells (BMCs). Our in vivo µ-CT and flow cytometry data further showed that CQ administration improves bone health and preserves bone micro-architecture by markedly raising the proportion of anti-osteoclastogenic immune cells, such as Th1 (p < 0.05), Th2 (p < 0.05), Tregs (p < 0.05), and Bregs (p < 0.01), while concurrently lowering the osteoclastogenic Th17 cells in bone marrow, mesenteric lymph nodes, Peyer's patches, and spleen in comparison to the control group. Serum cytokine analysis further supported the osteoprotective and immunoporotic potential of CQ, showing a significant increase in the levels of anti-osteoclastogenic cytokines (p < 0.05) (IFN-γ, IL-4, and IL-10) and a concurrent decrease in the levels of osteoclastogenic cytokines (p < 0.05) (TNF-α, IL-6, and IL-17). In conclusion, our data for the first time delineates the novel cellular and immunological mechanism of the osteoprotective potential of CQ under postmenopausal osteoporotic conditions.


Assuntos
Doenças Ósseas Metabólicas , Cissus , Osteoporose , Camundongos , Animais , Osteogênese , Densidade Óssea , Osteoporose/tratamento farmacológico , Estrogênios , Citocinas
2.
Endocrinology ; 163(10)2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35933634

RESUMO

In women, excess androgen causes polycystic ovary syndrome (PCOS), a common fertility disorder with comorbid metabolic dysfunctions including diabetes, obesity, and nonalcoholic fatty liver disease. Using a PCOS mouse model, this study shows that chronic high androgen levels cause hepatic steatosis while hepatocyte-specific androgen receptor (AR)-knockout rescues this phenotype. Moreover, through RNA-sequencing and metabolomic studies, we have identified key metabolic genes and pathways affected by hyperandrogenism. Our studies reveal that a large number of metabolic genes are directly regulated by androgens through AR binding to androgen response element sequences on the promoter region of these genes. Interestingly, a number of circadian genes are also differentially regulated by androgens. In vivo and in vitro studies using a circadian reporter [Period2::Luciferase (Per2::LUC)] mouse model demonstrate that androgens can directly disrupt the hepatic timing system, which is a key regulator of liver metabolism. Consequently, studies show that androgens decrease H3K27me3, a gene silencing mark on the promoter of core clock genes, by inhibiting the expression of histone methyltransferase, Ezh2, while inducing the expression of the histone demethylase, JMJD3, which is responsible for adding and removing the H3K27me3 mark, respectively. Finally, we report that under hyperandrogenic conditions, some of the same circadian/metabolic genes that are upregulated in the mouse liver are also elevated in nonhuman primate livers. In summary, these studies not only provide an overall understanding of how hyperandrogenism associated with PCOS affects liver gene expression and metabolism but also offer insight into the underlying mechanisms leading to hepatic steatosis in PCOS.


Assuntos
Hiperandrogenismo , Hepatopatia Gordurosa não Alcoólica , Síndrome do Ovário Policístico , Androgênios/metabolismo , Androgênios/farmacologia , Animais , Modelos Animais de Doenças , Epigênese Genética , Feminino , Histonas/metabolismo , Humanos , Hiperandrogenismo/complicações , Camundongos , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/genética , Síndrome do Ovário Policístico/metabolismo
3.
Biol Reprod ; 107(3): 813-822, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35657015

RESUMO

The anti-Müllerian hormone (AMH) produced by the granulosa cells of growing follicles is critical for folliculogenesis and is clinically used as a diagnostic and prognostic marker of female fertility. Previous studies report that AMH-pretreatment in mice creates a pool of quiescent follicles that are released following superovulation, resulting in an increased number of ovulated oocytes. However, the quality and developmental competency of oocytes derived from AMH-induced accumulated follicles as well as the effect of AMH treatment on live birth are not known. This study reports that AMH priming positively affects oocyte maturation and early embryonic development culminating in higher number of live births. Our results show that AMH treatment results in good-quality oocytes with greater developmental competence that enhances embryonic development resulting in blastocysts with higher gene expression. The transcriptomic analysis of oocytes from AMH-primed mice compared with those of control mice reveal that AMH upregulates a large number of genes and pathways associated with oocyte quality and embryonic development. Mitochondrial function is the most affected pathway by AMH priming, which is supported by more abundant active mitochondria, mitochondrial DNA content and adenosine triphosphate levels in oocytes and embryos isolated from AMH-primed animals compared with control animals. These studies for the first time provide an insight into the overall impact of AMH on female fertility and highlight the critical knowledge necessary to develop AMH as a therapeutic option to improve female fertility.


Assuntos
Hormônio Antimülleriano , Coeficiente de Natalidade , Animais , Hormônio Antimülleriano/genética , Hormônio Antimülleriano/metabolismo , Desenvolvimento Embrionário , Feminino , Nascido Vivo , Camundongos , Oócitos/metabolismo , Folículo Ovariano/metabolismo , Gravidez
4.
Endocrinology ; 163(5)2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35396990

RESUMO

In females, reproductive success is dependent on the expression of a number of genes regulated at different levels, one of which is through epigenetic modulation. How a specific epigenetic modification regulates gene expression and their downstream effect on ovarian function are important for understanding the female reproductive process. The trimethylation of histone3 at lysine27 (H3K27me3) is associated with gene repression. JMJD3 (or KDM6b), a jumonji domain-containing histone demethylase specifically catalyzes the demethylation of H3K27me3, that positively influences gene expression. This study reports that the expression of JMJD3 specifically in the ovarian granulosa cells (GCs) is critical for maintaining normal female fertility. Conditional deletion of Jmjd3 in the GCs results in a decreased number of total healthy follicles, disrupted estrous cycle, and increased follicular atresia culminating in subfertility and premature ovarian failure. At the molecular level, the depletion of Jmjd3 and RNA-seq analysis reveal that JMJD3 is essential for mitochondrial function. JMJD3-mediated reduction of H3K27me3 induces the expression of Lif (Leukemia inhibitory factor) and Ctnnb1 (ß-catenin), that in turn regulate the expression of key mitochondrial genes critical for the electron transport chain. Moreover, mitochondrial DNA content is also significantly decreased in Jmjd3 null GCs. Additionally, we have uncovered that the expression of Jmjd3 in GCs decreases with age, both in mice and in humans. Thus, in summary, our studies highlight the critical role of JMJD3 in nuclear-mitochondrial genome coordination that is essential for maintaining normal ovarian function and female fertility and underscore a potential role of JMJD3 in female reproductive aging.


Assuntos
Atresia Folicular , Histonas , Histona Desmetilases com o Domínio Jumonji/metabolismo , Animais , Feminino , Fertilidade/genética , Histonas/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Camundongos , Ovário/metabolismo
6.
PLoS Genet ; 17(3): e1009483, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33784295

RESUMO

Conventionally viewed as male hormone, androgens play a critical role in female fertility. Although androgen receptors (AR) are transcription factors, to date very few direct transcriptional targets of ARs have been identified in the ovary. Using mouse models, this study provides three critical insights about androgen-induced gene regulation in the ovary and its impact on female fertility. First, RNA-sequencing reveals a number of genes and biological processes that were previously not known to be directly regulated by androgens in the ovary. Second, androgens can also influence gene expression by decreasing the tri-methyl mark on lysine 27 of histone3 (H3K27me3), a gene silencing epigenetic mark. ChIP-seq analyses highlight that androgen-induced modulation of H3K27me3 mark within gene bodies, promoters or distal enhancers have a much broader impact on ovarian function than the direct genomic effects of androgens. Third, androgen-induced decrease of H3K27me3 is mediated through (a) inhibiting the expression and activity of Enhancer of Zeste Homologue 2 (EZH2), a histone methyltransferase that promotes tri-methylation of K27 and (b) by inducing the expression of a histone demethylase called Jumonji domain containing protein-3 (JMJD3/KDM6B), responsible for removing the H3K27me3 mark. Androgens through the PI3K/Akt pathway, in a transcription-independent fashion, increase hypoxia-inducible factor 1 alpha (HIF1α) protein levels, which in turn induce JMJD3 expression. Furthermore, proof of concept studies involving in vivo knockdown of Ar in the ovary and ovarian (granulosa) cell-specific Ar knockout mouse model show that ARs regulate the expression of key ovarian genes through modulation of H3K27me3.


Assuntos
Androgênios/metabolismo , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Regulação da Expressão Gênica , Histonas/metabolismo , Histona Desmetilases com o Domínio Jumonji/metabolismo , Ovário/metabolismo , Androgênios/farmacologia , Animais , Biologia Computacional/métodos , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Células da Granulosa/efeitos dos fármacos , Células da Granulosa/metabolismo , Camundongos , Ovário/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas c-akt , Transcriptoma
7.
Anticancer Agents Med Chem ; 20(12): 1431-1446, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31958041

RESUMO

Hydrogels are water-insoluble, hydrophilic, cross-linked, three-dimensional networks of polymer chains having the ability to swell and absorb water but do not dissolve in it, that comprise the major difference between gels and hydrogels. The mechanical strength, physical integrity and solubility are offered by the crosslinks. The different applications of hydrogels can be derived based on the methods of their synthesis, response to different stimuli, and their different kinds. Hydrogels are highly biocompatible and have properties similar to human tissues that make it suitable to be used in various biomedical applications, including drug delivery and tissue engineering. The role of hydrogels in cancer therapy is highly emerging in recent years. In the present review, we highlighted different methods of synthesis of hydrogels and their classification based on different parameters. Distinctive applications of hydrogels in the treatment of cancer are also discussed.


Assuntos
Antineoplásicos/farmacologia , Hidrogéis/farmacologia , Neoplasias/tratamento farmacológico , Antineoplásicos/síntese química , Antineoplásicos/química , Humanos , Hidrogéis/síntese química , Hidrogéis/química , Estrutura Molecular
8.
Curr Med Chem ; 27(23): 3906-3923, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30636575

RESUMO

Zika Virus (ZIKV) belongs to the class of flavivirus that can be transmitted by Aedes mosquitoes. The number of Zika virus caused cases of acute infections, neurological disorders and congenital microcephaly are rapidly growing and therefore, in 2016, the World Health Organization declared a global "Public Health Emergency of International Concern". Anti-ZIKV therapeutic and vaccine development strategies are growing worldwide in recent years, however, no specific and safe treatment is available till date to save the human life. Currently, development of peptide therapeutics against ZIKV has attracted rising attention on account of their high safety concern and low development cost, in comparison to small therapeutic molecules and antibody-based anti-viral drugs. In present review, an overview of ZIKV inhibition by peptide-based inhibitors including E-protein derived peptides, antimicrobial peptides, frog skin peptides and probiotic peptides has been discussed. Peptides inhibitors have also been reported to act against NS5, NS2B-NS3 protease and proteasome in order to inhibit ZIKV infection. Recent advances in peptide-based therapeutics and vaccine have been reviewed and their future promise against ZIKV infections has been explored.


Assuntos
Aedes , Infecção por Zika virus , Zika virus , Animais , Antivirais , Humanos , Peptídeos
9.
Endocrinology ; 160(7): 1684-1700, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150057

RESUMO

Intrauterine exposure to various adverse conditions during fetal development can lead to epigenetic changes in fetal tissues, predisposing those tissues to disease conditions later in life. An example is gestational diabetes (GD), where the offspring has a higher risk of developing obesity, metabolic disorders, or cardiovascular disease in adult life. In this study, using two well-established GD (streptozotocin- and high-fat and high-sugar-induced) mouse models, we report that female offspring from GD dams are predisposed toward fertility problems later in life. This predisposition to fertility problems is due to altered ovarian expression of a peptide called cocaine- and amphetamine-regulated transcript (CART), which is known to negatively affect folliculogenesis and is induced by elevated leptin levels. Results show that the underlying cause of this altered expression is due to fetal epigenetic modifications involving glucose- and insulin-induced miRNA, miR-101, and the phosphatidylinositol 3-kinase/Akt pathway. These signaling events regulate Ezh2, a histone methyltransferase that promotes H3K27me3, a gene-repressive mark, and CBP/p300, a histone acetyltransferase that promotes H3K27ac, a transcription activation mark, in the fetal ovary. Moreover, the CART promoter has depleted 5-methylcytosine (5mC) and enriched 5-hydroxymethylcytosine (5hmC) levels. The depletion of H3K27me3 and 5mC repressive marks and subsequent increase in H3K27ac and 5hmC gene-activating marks convert the Cartpt promoter to a "superpromoter." This makes the Cartpt promoter more sensitive to leptin levels that predispose the GD offspring to fertility problems. Therefore, this study provides a mechanistic insight about fetal epigenome reprogramming that manifests to ovarian dysfunction and subfertility later in adult life.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Gestacional/metabolismo , Epigênese Genética , Infertilidade/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Ovário/metabolismo , Regiões Promotoras Genéticas , Animais , Metilação de DNA , Diabetes Mellitus Experimental/genética , Diabetes Gestacional/genética , Feminino , Histonas/metabolismo , Infertilidade/genética , Camundongos , Proteínas do Tecido Nervoso/genética , Fosfatidilinositol 3-Quinases/metabolismo , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia
11.
Pharmacol Res ; 144: 8-18, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30951812

RESUMO

Plant lectins are non-immunoglobin in nature and bind to the carbohydrate moiety of the glycoconjugates without altering any of the recognized glycosyl ligands. Plant lectins have found applications as cancer biomarkers for recognizing the malignant tumor cells for the diagnosis and prognosis of cancer. Interestingly, plant lectins contribute to inducing cell death through autophagy and apoptosis, indicating their potential implication in cancer inhibitory mechanism. In the present review, anticancer activities of major plant lectins have been documented, with a detailed focus on the signaling circuit for the possible molecular targeted cancer therapy. In this context, several lectins have exhibited preclinical and clinical significance, driving toward therapeutic potential in cancer treatment. Moreover, several plant lectins induce immunomodulatory activities, and therefore, novel strategies have been established from preclinical and clinical investigations for the development of combinatorial treatment consisting of immunotherapy along with other anticancer therapies. Although the application of plant lectins in cancer is still in very preliminary stage, advanced high-throughput technology could pave the way for the development of lectin-based complimentary medicine for cancer treatment.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Lectinas de Plantas/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Humanos , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Neoplasias/imunologia , Neoplasias/patologia , Lectinas de Plantas/farmacologia
12.
Phytomedicine ; 55: 179-190, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30668428

RESUMO

BACKGROUND: Epithelial-to-mesenchymal transition (EMT), a key step in oral cancer progression, is associated with invasion, metastasis, and therapy resistance, thus targeting the EMT represents a critical therapeutic strategy for the treatment of oral cancer metastasis. Our previous study showed that Abrus agglutinin (AGG), a plant lectin, induces both intrinsic and extrinsic apoptosis to activate the tumor inhibitory mechanism. OBJECTIVE: This study aimed to investigate the role of AGG in modulating invasiveness and stemness through EMT inhibition for the development of antineoplastic agents against oral cancer. METHODS: The EMT- and stemness-related proteins were studied in oral cancer cells using Western blot analysis and fluorescence microscopy. The potential mechanisms of Snail downregulation through p73 activation in FaDu cells were evaluated using Western blot analysis, immunoprecipitation, confocal microscopy, and molecular docking analysis. Immunohistochemical staining of the tumor samples of AGG-treated FaDu-xenografted nude mice was performed. RESULTS: At the molecular level, AGG-induced p73 suppressed Snail expression, leading to EMT inhibition in FaDu cells. Notably, AGG promoted the translocation of Snail from the nucleus to the cytoplasm in FaDu cells and triggered its degradation through ubiquitination. In this setting, AGG inhibited the interaction between Snail and p73 in FaDu cells, resulting in p73 activation and EMT inhibition. Moreover, in epidermal growth factor (EGF)-stimulated FaDu cells, AGG abolished the upregulation of extracellular signal-regulated kinase (ERK)1/2 that plays a pivotal role in the upregulation of Snail to regulate the EMT phenotypes. In immunohistochemistry analysis, FaDu xenografts from AGG-treated mice showed decreased expression of Snail, SOX2, and vimentin and increased expression of p73 and E-cadherin compared with the control group, confirming EMT inhibition as part of its anticancer efficacy against oral cancer. CONCLUSION: In summary, AGG stimulates p73 in restricting EGF-induced EMT, invasiveness, and stemness by inhibiting the ERK/Snail pathway to facilitate the development of alternative therapeutics for oral cancer.


Assuntos
Transição Epitelial-Mesenquimal/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Lectinas de Plantas/farmacologia , Fatores de Transcrição da Família Snail/metabolismo , Proteína Tumoral p73/metabolismo , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Fator de Crescimento Epidérmico/metabolismo , Humanos , Camundongos Nus , Simulação de Acoplamento Molecular , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Lectinas de Plantas/química , Fatores de Transcrição da Família Snail/química , Fatores de Transcrição da Família Snail/genética , Proteína Tumoral p73/química , Proteína Tumoral p73/genética , Ubiquitinação , Regulação para Cima/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Cell Prolif ; 51(1)2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29171106

RESUMO

OBJECTIVE: We inspected the relevance of CD44, ABCB1 and ADAM17 in OSCC stemness and deciphered the role of autophagy/mitophagy in regulating stemness and chemoresistance. MATERIAL AND METHODS: A retrospective analysis of CD44, ABCB1 and ADAM17 with respect to the various clinico-pathological factors and their correlation was analysed in sixty OSCC samples. Furthermore, the stemness and chemoresistance were studied in resistant oral cancer cells using sphere formation assay, flow cytometry and florescence microscopy. The role of autophagy/mitophagy was investigated by transient transfection of siATG14, GFP-LC3, tF-LC3, mKeima-Red-Mito7 and Western blot analysis of autophagic and mitochondrial proteins. RESULTS: In OSCC, high CD44, ABCB1 and ADAM17 expressions were correlated with higher tumour grades and poor differentiation and show significant correlation in their co-expression. In vitro and OSCC tissue double labelling confirmed that CD44+ cells co-expresses ABCB1 and ADAM17. Further, cisplatin (CDDP)-resistant FaDu cells displayed stem-like features and higher CD44, ABCB1 and ADAM17 expression. Higher autophagic flux and mitophagy were observed in resistant FaDu cells as compared to parental cells, and inhibition of autophagy led to the decrease in stemness, restoration of mitochondrial proteins and reduced expression of CD44, ABCB1 and ADAM17. CONCLUSION: The CD44+ /ABCB1+ /ADAM17+ expression in OSCC is associated with stemness and chemoresistance. Further, this study highlights the involvement of mitophagy in chemoresistance and autophagic regulation of stemness in OSCC.


Assuntos
Proteína ADAM17/metabolismo , Autofagia/fisiologia , Resistencia a Medicamentos Antineoplásicos , Receptores de Hialuronatos/metabolismo , Neoplasias Bucais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Autofagia/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Neoplasias Bucais/tratamento farmacológico , Ativação Transcricional/efeitos dos fármacos , Ativação Transcricional/fisiologia , Regulação para Cima
14.
Environ Toxicol Pharmacol ; 55: 175-185, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28886471

RESUMO

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD; polycyclic aromatic hydrocarbon) is a persistent and ubiquitous environmental contaminant that causes a wide variety of deleterious effects. In this study, the DNA damage and apoptotic activity induced by TCDD was examined using in silico and in vitro approaches. In silico study showed that conformational changes and energies involved in the binding of TCDD to cytochrome P450 1B1 (CYP1B1) were crucial for its target proteins. Moreover, activated TCDD had high affinity to bind with aryl hydrocarbon receptor (AhR), with a binding energy of -564.7 Kcal/mol. Further, TCDD-CYP1B1 complex showed strong binding affinity for caspase 3, showing a binding energy of -518.5 Kcal/mol, and the docking of caspase inhibitors in the complex showed weak interaction with low binding energy as compared to TCDD-CYP1B1 caspase complexes. Interestingly, TCDD-induced apoptosis was significantly suppressed in Ac-DEVD-CMK-pretreated cells. The DNA damage activity of TCDD was quantified by comet tail formation and γ-H2AX foci formation in HaCaT cells. The role of CYP1B1 and AhR in DNA damage and apoptosis was demonstrated, and clotrimazole as well as knockdown of CYP1B1 and AhR could inhibit TCDD activation and suppress DNA damage followed by apoptosis in HaCaT cells. Moreover, TCDD increased expression of p53 and PUMA and our data showed that TCDD induced DNA damage followed by p53-mediated apoptosis. This study highlights the critical role of CYP1B1 and AhR in TCDD activity and proposes that inhibition of these key molecules might serve as a potential therapeutic approach for treatment of allergy and cancer.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Citocromo P-450 CYP1B1/metabolismo , Dano ao DNA , Dibenzodioxinas Policloradas/efeitos adversos , Receptores de Hidrocarboneto Arílico/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Apoptose , Linhagem Celular , Simulação por Computador , Citocromo P-450 CYP1B1/química , Exposição Ambiental/efeitos adversos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Dibenzodioxinas Policloradas/farmacologia , Conformação Proteica/efeitos dos fármacos
15.
Free Radic Biol Med ; 112: 452-463, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28843778

RESUMO

Mitophagy, a special type of autophagy, plays an important role in the mitochondria quality control and cellular homeostasis. In this study, we examined the molecular mechanism of mitophagy induction with benzo[a]pyrene (B[a]P), a ubiquitous polycyclic aromatic hydrocarbon, which acts as a prosurvival response against apoptotic cell death. Our study showed that B[a]P displayed higher cytotoxicity in autophagy-deficient HaCaT cells as compared to control. Further, we showed that B[a]P triggered the Beclin-1-dependent autophagy through the mammalian target of rapamycin (mTOR)/AMP-activated protein kinase (AMPK) pathway. Moreover, our study indicated that the B[a]P-induced autophagy was initiated through the activation of cytochrome P450 1B1 (CYP1B1) and the aryl hydrocarbon receptor (AhR) in HaCaT cells. Intriguingly, the B[a]P-induced Beclin-1-mediated mitophagy was suppressed in CYP1B1 and AhR knockdown HaCaT cells, indicating a crucial role of B[a]P activation in the mitophagy induction to regulate cell death. B[a]P was shown to increase the mitochondrial dysfunction and decrease the mitochondrial membrane potential, resulting in depletion of ATP level along with the inhibition of the oxygen consumption rate in HaCaT cells. Importantly, the supplementation of methyl pyruvate compensated for the B[a]P-induced drop in the ATP level and mitigated the reactive oxygen species burden and autophagy. Mechanistically, B[a]P inhibited the manganese superoxide dismutase (MnSOD) activity and we found that the activated mitochondrial CYP1B1 interacted with MnSOD, inflicting mitophagy to protect from B[a]P-induced apoptosis. In summary, our study reveals mitophagy induction as a cellular protection mechanism against B[a]P-triggered toxicity and carcinogenesis.


Assuntos
Apoptose/efeitos dos fármacos , Benzo(a)pireno/toxicidade , Carcinógenos/toxicidade , Queratinócitos/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Trifosfato de Adenosina/antagonistas & inibidores , Trifosfato de Adenosina/biossíntese , Apoptose/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteína Beclina-1/genética , Proteína Beclina-1/metabolismo , Linhagem Celular Transformada , Citocromo P-450 CYP1B1/genética , Citocromo P-450 CYP1B1/metabolismo , Relação Dose-Resposta a Droga , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Mitofagia/genética , Consumo de Oxigênio/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo
16.
Tumour Biol ; 39(5): 1010428317701634, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28459216

RESUMO

The accumulating evidences show that Abrus agglutinin, a plant lectin, displays a broad range of anticancer activity including cancer-specific induction of apoptosis; however, the underlying molecular mechanism of Abrus agglutinin-induced oral cancer stem cell elimination remains elusive. Our data documented that Abrus agglutinin effectively downregulated the CD44+ expression with the increased CD44- population in different oral cancer cells. After 24-h Abrus agglutinin treatment, FaDu cells were quantified for orosphere formation in ultra-low attachment plates and data showed that Abrus agglutinin inhibited the number and size of orosphere in a dose-dependent manner in FaDu cells. Furthermore, Abrus agglutinin hindered the plasticity of FaDu orospheres as supported by reduced sphere formation and downregulated the self-renewal property via inhibition of Wnt-ß-catenin signaling pathway. Introduction of LiCl, a glycogen synthase kinase 3ß inhibitor, rescued the Abrus agglutinin-stimulated inhibition of ß-catenin and phosphorylated glycogen synthase kinase 3ß in FaDu cell-derived orospheres confirming importance of Wnt signaling in Abrus agglutinin-mediated inhibition of stemness. In this connection, our data showed that Abrus agglutinin restrained proliferation and induced apoptosis in FaDu-derived cancer stem cells in dose-dependent manner. Moreover, western blot data demonstrated that Abrus agglutinin increased the Bax/Bcl-2 ratio with activation of poly(adenosine diphosphate-ribose) polymerase and caspase-3 favoring apoptosis induction in orospheres. Abrus agglutinin induced reactive oxygen species accumulation in orospheres and pretreatment of N-acetyl cysteine, and a reactive oxygen species scavenger inhibited Abrus agglutinin-mediated caspase-3 activity and ß-catenin expression indicating reactive oxygen species as a principal regulator of Wnt signaling and apoptosis. In conclusion, Abrus agglutinin has a potential role as an integrative therapeutic approach for combating oral cancer through targeting self-renewability of orospheres via reactive oxygen species-mediated apoptosis.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Autorrenovação Celular/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Lectinas de Plantas/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glicogênio Sintase Quinase 3 beta/antagonistas & inibidores , Glicogênio Sintase Quinase 3 beta/genética , Humanos , Receptores de Hialuronatos/genética , Cloreto de Lítio/administração & dosagem , Camundongos , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Células-Tronco Neoplásicas/efeitos dos fármacos , Lectinas de Plantas/química , Espécies Reativas de Oxigênio/metabolismo , Via de Sinalização Wnt/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
17.
Mol Carcinog ; 56(11): 2400-2413, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28543759

RESUMO

Oral cancer, a type of head and neck cancer, is ranked as one of the top most malignancies in India. Herein, we evaluated the anticancer efficacy of Abrus agglutinin (AGG), a plant lectin, in oral squamous cell carcinoma. AGG selectively inhibited cell growth, and caused cell cycle arrest and mitochondrial apoptosis through a reactive oxygen species (ROS)-mediated ATM-p73 dependent pathway in FaDu cells. AGG-induced ROS accumulation was identified as the major mechanism regulating apoptosis, DNA damage and DNA-damage response, which were significantly reversed by ROS scavenger N-acetylcysteine (NAC). Moreover, AGG was found to interact with mitochondrial manganese-dependent superoxide dismutase that might inhibit its activity and increase ROS in FaDu cells. In oral cancer p53 is mutated, thus we focused on p73; AGG resulted in p73 upregulation and knock down of p73 caused a decrease in AGG-induced apoptosis. Interestingly, AGG-dependent p73 expression was found to be regulated by ROS, which was reversed by NAC treatment. A reduction in the level of p73 in AGG-treated shATM cells was found to be associated with a decreased apoptosis. Moreover, administration of AGG (50 µg/kg body weight) significantly inhibited the growth of FaDu xenografts in athymic nude mice. In immunohistochemical analysis, the xenografts from AGG-treated mice displayed a decrease in PCNA expression and an increase in caspase-3 activation as compared to the controls. In conclusion, we established a connection among ROS, ATM and p73 in AGG-induced apoptosis, which might be useful in enhancing the therapeutic targeting of p53 deficient oral squamous cell carcinoma.


Assuntos
Antineoplásicos Fitogênicos/uso terapêutico , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Carcinoma de Células Escamosas/tratamento farmacológico , Dano ao DNA/efeitos dos fármacos , Neoplasias Bucais/tratamento farmacológico , Lectinas de Plantas/uso terapêutico , Proteína Tumoral p73/metabolismo , Abrus/química , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Modelos Moleculares , Boca/efeitos dos fármacos , Boca/metabolismo , Boca/patologia , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Espécies Reativas de Oxigênio/metabolismo
18.
Mol Carcinog ; 56(2): 389-401, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27182794

RESUMO

Abrus agglutinin (AGG), a type II ribosome-inactivating protein has been found to induce mitochondrial apoptosis. In the present study, we documented that AGG-mediated Akt dephosphorylation led to ER stress resulting the induction of autophagy-dependent cell death through the canonical pathway in cervical cancer cells. Inhibition of autophagic death with 3-methyladenine (3-MA) and siRNA of Beclin-1 and ATG5 increased AGG-induced apoptosis. Further, inhibiting apoptosis by Z-DEVD-FMK and N-acetyl cysteine (NAC) increased autophagic cell death after AGG treatment, suggesting that AGG simultaneously induced autophagic and apoptotic death in HeLa cells. Additionally, it observed that AGG-induced autophagic cell death in Bax knock down (Bax-KD) and 5-FU resistant HeLa cells, confirming as an alternate cell killing pathway to apoptosis. At the molecular level, AGG-induced ER stress in PERK dependent pathway and inhibition of ER stress by salubrinal, eIF2α phosphatase inhibitor as well as siPERK reduced autophagic death in the presence of AGG. Further, our in silico and colocalization study showed that AGG interacted with pleckstrin homology (PH) domain of Akt to suppress its phosphorylation and consequent downstream mTOR dephosphorylation in HeLa cells. We showed that Akt overexpression could not augment GRP78 expression and reduced autophagic cell death by AGG as compared to pcDNA control, indicating Akt modulation was the upstream signal during AGG's ER stress mediated autophagic cell death. In conclusion, we established that AGG stimulated cell death by autophagy might be used as an alternative tumor suppressor mechanism in human cervical cancer. © 2016 Wiley Periodicals, Inc.


Assuntos
Antineoplásicos/farmacologia , Autofagia/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Lectinas de Plantas/farmacologia , Domínios de Homologia à Plecstrina/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Inativadoras de Ribossomos Tipo 2/farmacologia , Abrus/química , Antineoplásicos/isolamento & purificação , Chaperona BiP do Retículo Endoplasmático , Feminino , Células HeLa , Humanos , Modelos Moleculares , Lectinas de Plantas/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt/química , Proteínas Inativadoras de Ribossomos Tipo 2/isolamento & purificação , Neoplasias do Colo do Útero/tratamento farmacológico , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologia , eIF-2 Quinase/metabolismo
19.
Toxicol Mech Methods ; 27(1): 1-17, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27919191

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) comprise the major class of cancer-causing chemicals and are ranked ninth among the chemical compounds threatening to humans. Moreover, interest in PAHs has been mainly due to their genotoxic, teratogenic, mutagenic and carcinogenic property. Polymorphism in cytochrome P450 (CYP450) and aryl hydrocarbon receptor (AhR) has the capacity to convert procarcinogens into carcinogens, which is an imperative factor contributing to individual susceptibility to cancer development. The carcinogenicity potential of PAHs is related to their ability to bind to DNA, thereby enhances DNA cross-linking, causing a series of disruptive effects which can result in tumor initiation. They induce cellular toxicity by regulating the generation of reactive oxygen species (ROS), which arbitrate apoptosis. Additionally, cellular toxicity-mediated apoptotic and autophagic cell death and immune suppression by industrial pollutants PAH, provide fertile ground for the proliferation of mutated cells, which results in cancer growth and progression. PAHs play a foremost role in angiogenesis necessary for tumor metastasization by promoting the upregulation of metalloproteinase-9 (MMP-9), vascular endothelial growth factor (VEGF) and hypoxia inducible factor (HIF) in human cancer cells. This review sheds light on the molecular mechanisms of PAHs induced cancer development as well as autophagic and apoptotic cell death. Besides that authors have unraveled how phytotherapeutics is an alternate potential therapeutics acting as a savior from the toxic effects of PAHs for safer and cost effective perspectives.


Assuntos
Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carcinógenos/toxicidade , Neoplasias/induzido quimicamente , Fitoterapia/métodos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Carcinogênese , Inibidores das Enzimas do Citocromo P-450/uso terapêutico , Sistema Enzimático do Citocromo P-450/biossíntese , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Preparações de Plantas/uso terapêutico , Receptores de Hidrocarboneto Arílico/metabolismo
20.
Oral Oncol ; 62: 122-135, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27865365

RESUMO

Conventional therapeutics are often frequented with recurrences, refraction and regimen resistance in oral cavity cancers which are predominantly manifested by cancer stem cells (CSCs). During oncoevolution, cancer cells may undergo structural and functional reprogramming wherein they evolve as highly tolerant CSC phenotypes with greater survival advantages. The CSCs possess inherent and exclusive properties including self-renewal, hierarchical differentiation, and tumorigenicity that serve as the basis of chemo-radio-resistance in oral cancer. However, the key mechanisms underlying the CSC-mediated therapy resistance need to be further elucidated. A spectrum of dysfunctional cellular pathways including the developmental signaling, apoptosis, autophagy, cell cycle regulation, DNA damage responses and epigenetic regulations protect the CSCs from conventional therapies. Moreover, tumor niche shelters CSCs and creates an immunosuppressive environment favoring the survival of CSCs. Maintenance of lower redox status, epithelial-to-mesenchymal transition (EMT), metabolic reprogramming and altered drug responses are the accessory features that aid in the process of chemo-radio-resistance in oral CSCs. This review deals with the functional and molecular basis of cancer cell pluripotency-associated resistance highlighting the abrupt fundamental cellular processes; targeting these events may hold a great promise in the successful treatment of oral cancer.


Assuntos
Neoplasias Bucais/patologia , Células-Tronco Neoplásicas/patologia , Antineoplásicos/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias Bucais/tratamento farmacológico
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