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1.
Nanomedicine ; 44: 102580, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35768037

RESUMO

Ultraviolet Beam (UVB) radiation is the main cause of skin cancer worldwide. Besides biocompatibility, the instability and limited skin permeability are the most challenging features of many effective photochemopreventive agents. (-)-Epigallocatechin-3-gallate (EGCG) is a natural polyphenolic compound extracted from Camellia sinensis that has been demonstrated to have antioxidant, anti-inflammatory, and anti-cancer properties. We evaluated the efficacy of three innovative EGCG nanoformulations in chemoprevention of UVB-induced DNA damage in keratinocytes. Results indicated that the EGCG nanoformulations reduced UVB-induced oxidative stress elevation and DNA damage. The nanoformulations also reduced the UVB-induced formation of pyrimidine and pyrimidone photoproducts in 2D human immortalized HaCaT keratinocytes and SKH-1 hairless mice through antioxidant effects and possibly through absorption of UVB radiation. In addition, EGCG nanoformulations inhibited UVB-induced chemokine/cytokine activation and promoted EGCG skin permeability and stability. Taken together, the results suggest the use of EGCG nanoformulations as potential natural chemopreventive agents during exposure to UVB radiation.


Assuntos
Catequina , Animais , Antioxidantes/farmacologia , Catequina/análogos & derivados , Catequina/farmacologia , Dano ao DNA , Humanos , Queratinócitos , Camundongos , Camundongos Pelados , Pele , Raios Ultravioleta
2.
Semin Cancer Biol ; 83: 413-421, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-33484869

RESUMO

Living host system possess mechanisms like innate immune system to combat against inflammation, stress singling, and cancer. These mechanisms are initiated by PAMP and DAMP mediated recognition by PRR. PRR is consist of variety of nucleic acid sensors like-RNA sensors. They play crucial role in identifying exogenous and endogenous RNA molecules, which subsequently mediate pro/inflammatory cytokine, IFN and ISGs response in traumatized or tumorigenic conditions. The sensors can sensitize wide range of nucleic acid particle in term of size and structure, while each category sensors belongs subclasses with differentially expressed in cell and distinguished functioning mechanisms. They are also able to make comparison between self and non-self-nucleic acid molecules through specific mechanisms. Besides exhibiting anti-inflammatory and anti-tumorigenic responses, RNA sensors cover the broad spectrum of response mechanisms. Transcriptionally RNA sensors undergo with tight epigenetic regulations. In this review study, we will be going to discuss about the details of RNA sensors, their functional mechanisms and epi-transactional regulations.


Assuntos
Ácidos Nucleicos , RNA , Epigênese Genética , Humanos , Imunidade Inata/genética , Inflamação , RNA/genética
3.
Cancer Rep (Hoboken) ; 5(2): e1459, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34245130

RESUMO

BACKGROUND: Data are steadily accruing that demonstrate that intestinal tumors are frequently derived from multiple founding cells, resulting in tumors comprised of distinct ancestral clones that might cooperate or alternatively compete, thereby potentially impacting different phases of the disease process. AIM: We sought to determine whether tumors with a multi-ancestral architecture involving at least two distinct clones show increased tumor number, growth, progression, or resistance to drug intervention. METHODS: Mice carrying the Min allele of Apc were generated that were mosaic with only a subset of cells in the intestinal epithelium expressing an activated form of PI3K, a key regulatory kinase affecting several important cellular processes. These cells were identifiable as they fluoresced green, whereas all other cells fluoresced red. RESULTS: Cell lineage tracing revealed that many intestinal tumors from our mouse model were derived from at least two founding cells, those expressing the activated PI3K (green) and those which did not (red). Heterotypic tumors with a multi-ancestral architecture as evidenced by a mixture of green and red cells exhibited increased tumor growth and invasiveness. Clonal architecture also had an impact on tumor response to low-dose aspirin. Aspirin treatment resulted in a greater reduction of heterotypic tumors derived from multiple founding cells as compared to tumors derived from a single founding cell. CONCLUSION: These data indicate that genetically distinct tumor-founding cells can contribute to early intratumoral heterogeneity. The coevolution of the founding cells and their progeny enhances colon tumor progression and impacts the response to aspirin. These findings are important to a more complete understanding of tumorigenesis with consequences for several distinct models of tumor evolution. They also have practical implications to the clinic. Mouse models with heterogenous tumors are likely better for predicting drug efficacy as compared to models in which the tumors are highly homogeneous. Moreover, understanding how interactions among different populations in a single heterotypic tumor with a multi-ancestral architecture impact response to a single agent and combination therapies are necessary to fully develop personalized medicine.


Assuntos
Transformação Celular Neoplásica/genética , Neoplasias Intestinais/genética , Animais , Antineoplásicos/farmacologia , Carcinogênese/genética , Carcinogênese/patologia , Transformação Celular Neoplásica/patologia , Modelos Animais de Doenças , Progressão da Doença , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Intestinais/tratamento farmacológico , Neoplasias Intestinais/patologia , Camundongos , Camundongos Transgênicos
4.
Sci Rep ; 11(1): 11935, 2021 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-34099820

RESUMO

Maytenus roylanus (MEM) is a plant with anti-proliferative effects against prostate cancer. We aimed to explore the mechanism of action of MEM in prostate cancer (PCa) by employing an in vitro global proteome approach to get useful information of various signaling pathways and effected genes to define the mechanism of MEM action in prostate cancer. We conducted a global proteome analysis of CWR22Rv1after treatment with methanolic extract of MEM. The result of the proteomic profiling of in vitro PCa cells demonstrated the reduction in tumor protein D52 (TPD52) expression after treatment with methanolic extract of MEM. Down-regulation of TPD52 expression at mRNA level was observed by MEM treatment in CWR22Rν1 and C4-2 cells in a dose-dependent fashion probably by cleavage of Caspase 3 and PARP, or by modulation of cyclin-dependent kinases in CWR22Rν1 and C4-2 cells. The progressive character of the TRAMP model demonstrates a chance to evaluate the potential of chemo-preventive agents for both initial and late stages of prostate cancer development, and induction in TPD52 protein expression with development as well as the progression of prostate cancer was observed in the TRAMP model. Analyses of the tissue microarray collection of 25 specimens confirmed the clinical significance of our findings identifying TPD52 as a potential marker for PCa progression. We determined that knockdown of TPD52 (CWR22Rν1 cells), a considerable downregulation was seen at the protein level. Downregulation of TPD52 inhibited the migration and invasive behavior of prostate cancer cells as observed. Moreover, we observed that the siRNA-TPD52 transfection of CWR22Rν1 cells resulted in tumor growth inhibition with a marked reduction in the secretion of prostate-specific antigen (PSA) in the serum. Intraperitoneal injection of MEM considerably slowed tumor growth in athymic mice, inhibited TPD52 expression, and caused a marked reduction in PSA levels of serum as demonstrated by immunoblot screening and immune-histochemical staining. This report illustrates a molecular overview of pathological processes in PCa, indicating possible new disease biomarkers and therapeutic targets.


Assuntos
Maytenus/química , Proteínas de Neoplasias/metabolismo , Extratos Vegetais/farmacologia , Neoplasias da Próstata/metabolismo , Proteômica/métodos , Análise Serial de Tecidos/métodos , Animais , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos Nus , Proteínas de Neoplasias/genética , Células PC-3 , Extratos Vegetais/administração & dosagem , Folhas de Planta/química , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Interferência de RNA , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
5.
Semin Cancer Biol ; 69: 129-139, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-31866477

RESUMO

Nano metal organic frameworks (NMOFs) belong to the group of nanoporous materials. Over the decades, the conducted researches explored the area for the potential applications of NMOFs in areas like biomedical, chemical engineering and materials science. Recently, NMOFs have been explored for their potential use in cancer diagnosis and therapeutics. The excellent physico-chemical features of NMOFs also make them a potential candiadate to facilitate drug design, delivery and storage against cancer cells. In this review, we have explored the characterstic features, synthesis methods, NMOFs based drug delivery, diagnosis and imaging in various cancer types. In addition to this, we have also pondered on the stability and toxicological concerns of NMOFs. Despite, a significant research has been done for the potential use of NMOFs in cancer diagonostic and therapeutics, more information regarding the stability, in-vivo clearance, toxicology, and pharmacokinetics is still needed to ehnace the use of NMOFs in cancer diagonostic and therapeutics.


Assuntos
Antineoplásicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Estruturas Metalorgânicas/administração & dosagem , Nanomedicina , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Animais , Humanos , Estruturas Metalorgânicas/química , Nanopartículas/química , Neoplasias/patologia
6.
Surgeon ; 19(5): e146-e152, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33121877

RESUMO

AIM: Early diagnosis of colorectal cancer (CRC) improves outcome. Straight-To-Test (STT) pathway was introduced in Whittington Hospital in 2012. The aim was to reduce the time to first oncological treatment and minimise unnecessary outpatient clinic appointments. However, this pathway has added significant burden to the trust in terms of number of procedures to be done.We assessed the diagnostic yield and the effectiveness of this pathway in improving the time to diagnosis of colorectal cancer. We also performed a cost-effective analysis and discussed the current literature along with interventions to further improve the benefits of STT investigations. METHOD: This is a prospectively collected data of all patients who underwent STT examinations in a single centre from January 2012 till December 2018. The parameters collected were patient details, procedures performed, findings and discharge plan. We also performed a cost-effective analysis. RESULTS: A total 1648 (90.8%) of patients identified suitable for STT pathway underwent colonoscopy or flexible sigmoidoscopy. From this, 764 (50.2%) patients had diagnosed pathology and CRC was detected in 50(3%) of the patients. We also estimated annual savings of £ 21,599.54 (£151,196.76 in seven years). Patients on the STT pathway took 25 days to obtain results as compared to 40 days in the standard pathway. The decision to take the patient off the cancer pathway was shortened by 3 weeks. CONCLUSION: STT pathway has proven to be safe and cost-effective means of investigation. However, further improvement is needed in the implementation to make it a sustainable. mode of investigation in long run and increase the pickup rate of colorectal cancer through STT.


Assuntos
Neoplasias Colorretais , Detecção Precoce de Câncer , Colonoscopia , Neoplasias Colorretais/diagnóstico , Análise Custo-Benefício , Humanos , Programas de Rastreamento , Sigmoidoscopia
7.
Prostate ; 81(1): 41-49, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33095939

RESUMO

INTRODUCTION OR OBJECTIVE: Men with favorable-risk prostate cancer (PCa) on active surveillance may benefit from intervention strategies to slow or prevent disease progression and the need for definitive treatment. Pomegranate and its extracts have shown antiproliferative and proapoptotic effects in cell lines and animal models, but its effect on human prostate cancer as a target tissue remain unclear. Objectives of this trial include pomegranate's ability to alter serum and prostate tissue biomarkers and the ability of an active surveillance cohort to adhere to a chemoprevention trial for 1 year. METHODS: Men with organ-confined, favorable-risk PCa on AS were randomly assigned to receive pomegranate fruit extract (PFE) 1000 mg (n = 15) or placebo (n = 15) once daily for twelve months. Prostate biopsies were performed at study entry and upon completion of the 1-year intervention. Plasma and urinary biomarkers were analyzed utilizing immunoassays and HPLC. Tissue proteins were assessed by immunohistochemistry (IHC) and measured by automated quantitation. RESULTS: PFE was well-tolerated with no significant toxicities. One patient withdrew before study initiation and 29 completed the 1-year intervention. No differences in plasma insulin-like growth factor-1 (IGF-1) levels, prostate-specific antigen doubling time, or biopsy kinetics were observed. Metabolites including urolithin A and urolithin A-gluc were detected more frequently in the PFE arm in both urine and plasma (p < .001 and p = .006, respectively). IHC analyses revealed reductions from baseline in 8-OHdG (a DNA damage marker) (p = .01) and androgen receptor expression (p = .04) in prostate tumor associated with PFE treatment. CONCLUSION: PFE administration for 12-month was well-tolerated and the protocol followed in an active surveillance population. Analyses suggest that PFE contains bioactive compounds capable of altering biomarkers involving oxidative stress and androgen signaling in prostate tumor and normal-appearing adjacent tissue. No alterations in the IGF axis were noted. This finding of study adherence and target activity provides a rationale for the further investigation of PFE in the active surveillance population.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Extratos Vegetais/administração & dosagem , Punica granatum/química , Neoplasias da Próstata/tratamento farmacológico , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/urina , Biópsia , Frutas/química , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Calicreínas/sangue , Masculino , Pessoa de Meia-Idade , Fitoterapia , Placebos , Extratos Vegetais/isolamento & purificação , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Neoplasias da Próstata/urina , Conduta Expectante
8.
Oxid Med Cell Longev ; 2020: 9535426, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33178389

RESUMO

Trastuzumab (TZM) is a humanized monoclonal antibody that has been approved for the clinical management of HER2-positive metastatic breast and gastric cancers but its use is limited by its cumulative dose and off-target cardiotoxicity. Unfortunately, till date, there is no approved antidote to this off-target toxicity. Therefore, an acute study was designed at investigating the protective potential and mechanism(s) of CVE and IGE in TZM-induced cardiotoxicity utilizing cardiac enzyme and oxidative stress markers and histopathological endpoints. 400 mg/kg/day CVE and IGE dissolved in 5% DMSO in sterile water were investigated in Wistar rats injected with 2.25 mg/kg/day/i.p. route of TZM for 7 days, using serum cTnI and LDH, complete lipid profile, cardiac tissue oxidative stress markers assays, and histopathological examination of TZM-intoxicated heart tissue. Results showed that 400 mg/kg/day CVE and IGE profoundly attenuated increases in the serum cTnI and LDH levels but caused no significant alterations in the serum lipids and weight gain pattern in the treated rats. CVE and IGE profoundly attenuated alterations in the cardiac tissue oxidative stress markers' activities while improving TZM-associated cardiac histological lesions. These results suggest that CVE and IGE could be mediating its cardioprotection via antioxidant, free radical scavenging, and antithrombotic mechanisms, thus, highlighting the therapeutic potentials of CVE and IGE in the management of TZM-mediated cardiotoxicity.


Assuntos
Cardiotoxicidade , Celulose/química , Clerodendrum/química , Extratos Vegetais/farmacologia , Sementes/química , Trastuzumab/efeitos adversos , África , Animais , Cardiotoxicidade/tratamento farmacológico , Cardiotoxicidade/metabolismo , Cardiotoxicidade/patologia , Masculino , Extratos Vegetais/química , Ratos , Ratos Wistar , Trastuzumab/farmacologia
9.
J Toxicol ; 2020: 8859716, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32714390

RESUMO

Doxorubicin is widely applied in hematological and solid tumor treatment but limited by its off-target cardiotoxicity. Thus, cardioprotective potential and mechanism(s) of CVE in DOX-induced cardiotoxicity were investigated using cardiac and oxidative stress markers and histopathological endpoints. 50-400 mg/kg/day CVE in 5% DMSO in distilled water were investigated in Wistar rats intraperitoneally injected with 2.5 mg/kg DOX on alternate days for 14 days, using serum troponin I and LDH, complete lipid profile, cardiac tissue oxidative stress marker assays, and histopathological examination of DOX-treated cardiac tissue. Preliminary qualitative and quantitative assays of CVE's secondary metabolites were also conducted. Phytochemical analyses revealed the presence of flavonoids (34.79 ± 0.37 mg/100 mg dry extract), alkaloids (36.73 ± 0.27 mg/100 mg dry extract), reducing sugars (07.78 ± 0.09 mg/100 mg dry extract), and cardiac glycosides (24.55 ± 0.12 mg/100 mg dry extract). 50-400 mg/kg/day CVE significantly attenuated increases in the serum LDH and troponin I levels. Similarly, the CVE dose unrelatedly decreased serum TG and VLDL-c levels without significant alterations in the serum TC, HDL-c, and LDL-c levels. Also, CVE profoundly attenuated alterations in the cardiac tissue oxidative stress markers' activities while improving DOX-associated cardiac histological lesions that were possibly mediated via free radical scavenging and/or antioxidant mechanisms. Overall, CVE may play a significant therapeutic role in the management of DOX-induced cardiotoxicity in humans.

10.
Nanomedicine (Lond) ; 15(11): 1147-1162, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32292109

RESUMO

Many dietary polyphenols have been investigated for their therapeutic potential either as single agents or in combinations. Despite the significant anticancer potential of these polyphenols in in vitro cell culture and in vivo animal models, their clinical applications have been limited because of challenges such as ineffective systemic delivery, stability and low bioavailability. Nanoencapsulation of these polyphenols could prolong circulation, improve localization, enhance efficacy and reduce the chances of multidrug resistance. This review summarized the use of various polyphenols especially epigallocatechin gallate, quercetin, curcumin and resveratrol as nanoformulations for cancer prevention and treatment. Despite some success, more research is warranted to design a nanoencapsulated combination of polyphenols, effective in in vitro, in vivo and human systems.


Assuntos
Catequina , Curcumina , Neoplasias , Animais , Catequina/farmacologia , Curcumina/farmacologia , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/prevenção & controle , Polifenóis/farmacologia , Quercetina , Resveratrol
11.
Oxid Med Cell Longev ; 2019: 6726312, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827691

RESUMO

Plant-based therapies are being explored to prevent or treat several cancer types. The antioxidant properties of Polyalthia longifolia plant are well established. In our previous work, we demonstrated the presence of cytotoxic compounds in the methanol extract of Polyalthia longifolia (MEP) with potent activity against human leukemia cells. In the present study, we evaluated the efficacy of MEP against prostate cancer (PCa) and established the molecular basis of its effect in in vitro and in vivo models. We observed that MEP treatment resulted in a significant decrease in the growth and viability of PCa cells, associated with arrest in the G1/S phase of the cell cycle. Apoptosis was confirmed as the primary mode of MEP-induced cell death through activation of the intrinsic apoptotic machinery. Proteomic and biochemical studies identified BiP as an important target of MEP with the activation of the ER stress pathway, as a potential mechanism driving MEP-induced apoptosis. The extract exhibited strong efficacy in the PCa xenograft mouse model with significant inhibition of tumor growth and reduced tumor burden. Taken together, our findings indicate that MEP-induced apoptosis in PCa cells concomitant with the activation of the ER stress pathways results in the inhibition of tumor growth, in vitro and in vivo. Our studies provide initial evidence of the efficacy of MEP against PCa and advocate for in-depth studies in other preclinical models for its possible use in clinical settings.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Fitoterapia , Extratos Vegetais/farmacologia , Polyalthia/química , Neoplasias da Próstata/tratamento farmacológico , Animais , Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Técnicas In Vitro , Masculino , Camundongos , Camundongos Nus , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Cells ; 8(9)2019 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-31540162

RESUMO

Psoriasis is a chronic immune-mediated skin disease that involves the interaction of immune and skin cells, and is characterized by cytokine-driven epidermal hyperplasia, deviant differentiation, inflammation, and angiogenesis. Because the available treatments for psoriasis have significant limitations, dietary products are potential natural sources of therapeutic molecules, which can repair the molecular defects associated with psoriasis and could possibly be developed for its management. Fisetin (3,7,3',4'-tetrahydroxyflavone), a phytochemical naturally found in pigmented fruits and vegetables, has demonstrated proapoptotic and antioxidant effects in several malignancies. This study utilized biochemical, cellular, pharmacological, and tissue engineering tools to characterize the effects of fisetin on normal human epidermal keratinocytes (NHEKs), peripheral blood mononuclear cells (PBMC), and CD4+ T lymphocytes in 2D and 3D psoriasis-like disease models. Fisetin treatment of NHEKs dose- and time-dependently induced differentiation and inhibited interleukin-22-induced proliferation, as well as activation of the PI3K/Akt/mTOR pathway. Fisetin treatment of TNF-α stimulated NHEKs also significantly inhibited the activation of p38 and JNK, but had enhanced effect on ERK1/2 (MAPK). In addition, fisetin treatment significantly decreased the secretion of Th1/Th-17 pro-inflammatory cytokines, particularly IFN-γ and IL-17A by 12-O-tetradecanolylphorbol 13-acetate (TPA)-stimulated NHEKs and anti-CD3/CD28-activated human PBMCs. Furthermore, we established the in vivo relevance of fisetin functions, using a 3D full-thickness human skin model of psoriasis (FTRHSP) that closely mimics in vivo human psoriatic skin lesions. Herein, fisetin significantly ameliorated psoriasis-like disease features, and decreased the production of IL-17 by CD4+ T lymphocytes co-cultured with FTRHSP. Collectively, our data identify the prodifferentiative, antiproliferative, and anti-inflammatory effects of fisetin, via modulation of the PI3K-Akt-mTOR and p38/JNK pathways and the production of cytokines in 2D and 3D human skin models of psoriasis. These results suggest that fisetin has a great potential to be developed as an effective and inexpensive agent for the treatment of psoriasis and other related inflammatory skin disorders.


Assuntos
Flavonoides/farmacologia , Inflamação/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Modelos Biológicos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Psoríase/tratamento farmacológico , Pele/efeitos dos fármacos , Serina-Treonina Quinases TOR/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Flavonóis , Humanos , Inflamação/metabolismo , Inflamação/patologia , Queratinócitos/efeitos dos fármacos , Queratinócitos/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Psoríase/metabolismo , Psoríase/patologia , Pele/patologia , Serina-Treonina Quinases TOR/metabolismo
13.
Int J Cancer ; 145(11): 3022-3032, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-31018249

RESUMO

The normal colon epithelium is transformed into its neoplastic counterpart through a series of genetic alterations in driver genes including activating mutations in PIK3CA. Treatment often involves surgery followed by 5-fluorouracil (5-FU) based therapy, which has limited efficiency and serious side effects. We sought to determine whether fisetin, a dietary flavonoid, alone or in combination with 5-FU affected tumorigenesis in the mammalian intestine. We first determined the effect of fisetin, 5-FU or their combination on PIK3CA-mutant and PIK3CA wild-type colon cancer cells by assessing cell viability, colony formation, apoptosis and effects on PI3K/AKT/mTOR signaling. Treatment of PIK3CA-mutant cells with fisetin and 5-FU reduced the expression of PI3K, phosphorylation of AKT, mTOR, its target proteins, constituents of mTOR signaling complex and this treatment increased the phosphorylation of AMPKα. We then determined whether fisetin and 5-FU together or singly affected tumorigenesis in ApcMin/+ mice that also express constitutively active PI3K in the distal small intestine and colon. Tumor incidence was markedly lower in fisetin-treated FC1 3K1 ApcMin/+ mice that also express constitutively active PI3K in distal small intestine and colon, as compared to control animals, indicating that fisetin is a strong preventive agent. In addition, the combination of fisetin and 5-FU also reduced the total number of intestinal tumors. Fisetin could be used as a preventive agent plus an adjuvant with 5-FU for the treatment of PIK3CA-mutant colorectal cancer.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases/genética , Neoplasias Colorretais/tratamento farmacológico , Flavonoides/administração & dosagem , Fluoruracila/administração & dosagem , Mutação , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Colorretais/genética , Sinergismo Farmacológico , Flavonoides/farmacologia , Flavonóis , Fluoruracila/farmacologia , Células HCT116 , Células HT29 , Humanos , Camundongos , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
14.
FASEB J ; 33(3): 3198-3211, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30379590

RESUMO

Growth factor receptor-binding protein 10 (GRB10) is a well-known adaptor protein and a recently identified substrate of the mammalian target of rapamycin (mTOR). Depletion of GRB10 increases insulin sensitivity and overexpression suppresses PI3K/Akt signaling. Because the major reason for the limited efficacy of PI3K/Akt-targeted therapies in prostate cancer (PCa) is loss of mTOR-regulated feedback suppression, it is therefore important to assess the functional importance and regulation of GRB10 under these conditions. On the basis of these background observations, we explored the status and functional impact of GRB10 in PCa and found maximum expression in phosphatase and tensin homolog (PTEN)-deficient PCa. In human PCa samples, GRB10 inversely correlated with PTEN and positively correlated with pAKT levels. Knockdown of GRB10 in nontumorigenic PTEN null mouse embryonic fibroblasts and tumorigenic PCa cell lines reduced Akt phosphorylation and selectively activated a panel of receptor tyrosine kinases. Similarly, overexpression of GRB10 in PTEN wild-type PCa cell lines accelerated tumorigenesis and induced Akt phosphorylation. In PTEN wild-type PCa, GRB10 overexpression promoted mediated PTEN interaction and degradation. PI3K (but not mTOR) inhibitors reduced GRB10 expression, suggesting primarily PI3K-driven regulation of GRB10. In summary, our results suggest that GRB10 acts as a major downstream effector of PI3K and has tumor-promoting effects in prostate cancer.-Khan, M. I., Al Johani, A., Hamid, A., Ateeq, B., Manzar, N., Adhami, V. M., Lall, R. K., Rath, S., Sechi, M., Siddiqui, I. A., Choudhry, H., Zamzami, M. A., Havighurst, T. C., Huang, W., Ntambi, J. M., Mukhtar, H. Proproliferatve function of adaptor protein GRB10 in prostate carcinoma.


Assuntos
Proteína Adaptadora GRB10/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Animais , Carcinógenos/antagonistas & inibidores , Carcinógenos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/fisiologia , Fibroblastos/citologia , Fibroblastos/metabolismo , Proteína Adaptadora GRB10/antagonistas & inibidores , Proteína Adaptadora GRB10/genética , Técnicas de Silenciamento de Genes , Humanos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Modelos Biológicos , PTEN Fosfo-Hidrolase/deficiência , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Neoplasias da Próstata/genética , RNA Mensageiro , Transdução de Sinais
15.
Mol Cancer Ther ; 18(2): 356-363, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30446585

RESUMO

Hyperactivated AKT kinase due to loss of its negative regulator PTEN influences many aspects of cancer biology, including chromatin. AKT primarily regulates acetyl-CoA production and phosphorylates many histone-modulating enzymes, resulting in their activation or inhibition. Therefore, understanding the therapeutic impact of AKT inhibition on chromatin-related events is essential. Here, we report that AKT inhibition in prostate-specific PTEN knockout mice significantly induces di- and trimethylation of H3K4 with concomitant reduction in H3K9 acetylation. Mechanistically, we observed that AKT inhibition reduces expression of the H3K4 methylation-specific histone demethylases KDM5 family, especially KDM5B expression at transcriptional levels. Furthermore, we observed that AKT negatively regulates miR-137 levels, which transcriptionally represses KDM5B expression. Overexpression of miR-137 significantly reduced KDM5B and increased H3K4 methylation levels but failed to change AKT phosphorylation. Overall, we observed that AKT transcriptionally regulates KDM5B mainly via repression of miR-137. Our data identify a mechanism by which AKT kinase modulates the prostate cancer epigenome through regulating H3K4 methylation. Additional studies on AKT inhibition-mediated induction of H3K4 methylation will help in designing strategies to enhance the therapeutic efficacy of PI3K/AKT inhibitors.


Assuntos
Histona Desmetilases com o Domínio Jumonji/genética , MicroRNAs/genética , Proteínas Nucleares/genética , PTEN Fosfo-Hidrolase/genética , Fosforilcolina/análogos & derivados , Neoplasias da Próstata/tratamento farmacológico , Proteínas Repressoras/genética , Acetilação/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Inativação de Genes , Humanos , Masculino , Metilação/efeitos dos fármacos , Camundongos , Fosforilcolina/administração & dosagem , Fosforilcolina/farmacologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Nutrients ; 11(1)2018 Dec 25.
Artigo em Inglês | MEDLINE | ID: mdl-30585192

RESUMO

Tea is the most widely used beverage worldwide. Japanese and Chinese people have been drinking tea for centuries and in Asia, it is the most consumed beverage besides water. It is a rich source of pharmacologically active molecules which have been implicated to provide diverse health benefits. The three major forms of tea are green, black and oolong tea based on the degree of fermentation. The composition of tea differs with the species, season, leaves, climate, and horticultural practices. Polyphenols are the major active compounds present in teas. The catechins are the major polyphenolic compounds in green tea, which include epigallocatechin-3-gallate (EGCG), epigallocatechin, epicatechin-3-gallate and epicatechin, gallocatechins and gallocatechin gallate. EGCG is the predominant and most studied catechin in green tea. There are numerous evidences from cell culture and animal studies that tea polyphenols have beneficial effects against several pathological diseases including cancer, diabetes and cardiovascular diseases. The polyphenolic compounds present in black tea include theaflavins and thearubigins. In this review article, we will summarize recent studies documenting the role of tea polyphenols in the prevention of cancer, diabetes, cardiovascular and neurological diseases.


Assuntos
Polifenóis/química , Polifenóis/farmacologia , Chá/química , Doenças Cardiovasculares/prevenção & controle , Doenças do Sistema Nervoso Central/prevenção & controle , Diabetes Mellitus/prevenção & controle , Humanos , Neoplasias/prevenção & controle
17.
Sci Rep ; 8(1): 15726, 2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30356079

RESUMO

The anti-proliferative activity of dietary flavonoid fisetin has been validated in various cancer models. Establishing its precise mechanism of action has proved somewhat challenging given the multiplicity of its targets. We demonstrated that YB-1 promotes epithelial-to-mesenchymal transition and its inhibition suppressed tumor cell proliferation and invasion. The p90 ribosomal S6 kinase (RSK), an important ERK effector, activates YB-1 to drive melanoma growth. We found that fisetin treatment of monolayer/3-D melanoma cultures resulted in YB-1 dephosphorylation and reduced transcript levels. In parallel, fisetin suppressed mesenchymal markers and matrix-metalloproteinases in melanoma cells. Data from cell-free/cell-based systems indicated that fisetin inhibited RSK activity through binding to the kinase. Affinity studies for RSK isoforms evaluated stronger interaction for RSK2 than RSK1. Competition assays performed to monitor binding responses revealed that YB-1 and RSK2 do not compete, rather binding of fisetin to RSK2 promotes its binding to YB-1. Fisetin suppressed YB-1/RSK signaling independent of its effect on ERK, and reduced MDR1 levels. Comparable efficacy of fisetin and vemurafenib for inhibiting melanoma growth was noted albeit through divergent modulation of ERK. Our studies provide insight into additional modes of regulation through which fisetin interferes with melanoma growth underscoring its potential therapeutic efficacy in disease progression.


Assuntos
Flavonoides/farmacologia , Melanoma/tratamento farmacológico , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteína 1 de Ligação a Y-Box/antagonistas & inibidores , Antineoplásicos/farmacologia , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Flavonóis , Humanos , Sistema de Sinalização das MAP Quinases , Melanoma/patologia , Fosforilação , Transdução de Sinais , Transcrição Gênica/efeitos dos fármacos , Proteína 1 de Ligação a Y-Box/metabolismo
18.
J Glob Oncol ; 4: 1-10, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30241135

RESUMO

Therapies originating from traditional medical systems are widely used by patients in both India and the United States. The first India-US Workshop on Traditional Medicine was held in New Delhi, India, on March 3 and 4, 2016, as a collaboration between the Ministry of Ayurveda, Yoga and Naturopathy, Unani, Siddha, and Homoeopathy (AYUSH) of the Government of India, the US National Cancer Institute (NCI), National Institutes of Health, and the Office of Global Affairs, US Department of Health and Human Services. It was attended by Indian and US policymakers, scientists, academics, and medical practitioners from various disciplines. The workshop provided an opportunity to open a dialogue between AYUSH and NCI to identify promising research results and potential topics for Indo-US collaboration. Recommendations that emerged from the workshop underlined the importance of applying rational and scientific approaches for drug development; standardizing traditional medicine products and procedures to ensure reliability and reproducibility; promotion of collaboration between Indian traditional medicine practitioners and researchers and US researchers; greater integration of evidence-based traditional medicine practices with mainstream medical practices in India; and development of training programs between AYUSH and NCI to facilitate crosstraining. Several positive developments took place after the thought-provoking deliberations.


Assuntos
Medicina Baseada em Evidências , Medicina Tradicional , Pesquisa , Desenvolvimento de Medicamentos , Educação Médica , Humanos , Índia , Medicina Tradicional/métodos , Neoplasias/terapia , Estados Unidos
19.
Int J Nanomedicine ; 13: 4189-4206, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30057446

RESUMO

BACKGROUND: Psoriasis is a chronic and currently incurable inflammatory skin disease characterized by hyperproliferation, aberrant differentiation, and inflammation, leading to disrupted skin barrier function. The use of natural agents that can abrogate these effects could be useful for the treatment of psoriasis. Earlier studies have shown that treatment of keratinocytes and mouse skin with the green tea polyphenol (-)-epigallocatechin-3-gallate (EGCG) mitigated inflammation and increased the expression of caspase-14 while promoting epidermal differentiation and cornification. However, bioavailability issues have restricted the development of EGCG for the treatment of psoriasis. MATERIALS AND METHODS: To overcome these limitations, we employed a chitosan-based polymeric nanoparticle formulation of EGCG (CHI-EGCG-NPs, hereafter termed nanoEGCG) suitable for topical delivery for treating psoriasis. We investigated and compared the efficacy of nanoEGCG versus native or free EGCG in vitro and in an in vivo imiquimod (IMQ)-induced murine psoriasis-like dermatitis model. The in vivo relevance and efficacy of nanoEGCG formulation (48 µg/mouse) were assessed in an IMQ-induced mouse psoriasis-like skin lesion model compared to free EGCG (1 mg/mouse). RESULTS: Like free EGCG, nanoEGCG treatment induced differentiation, and decreased proliferation and inflammatory responses in cultured keratinocytes, but with a 4-fold dose advantage. Topically applied nanoEGCG elicited a significant (p<0.01) amelioration of psoriasiform pathological markers in IMQ-induced mouse skin lesions, including reductions in ear and skin thickness, erythema and scales, proliferation (Ki-67), infiltratory immune cells (mast cells, neutrophils, macrophages, and CD4+ T cells), and angiogenesis (CD31). We also observed increases in the protein expression of caspase-14, early (keratin-10) and late (filaggrin and loricrin) markers of differentiation, and the activator protein-1 factor (JunB). Importantly, a significant modulation of several psoriasis-related inflammatory cytokines and chemokines was observed compared to the high dose of free EGCG (p<0.05). Taken together, topically applied nanoEGCG displayed a >20-fold dose advantage over free EGCG. CONCLUSION: Based on these observations, our nanoEGCG formulation represents a promising drug-delivery strategy for treating psoriasis and possibly other inflammatory skin diseases.


Assuntos
Aminoquinolinas/toxicidade , Catequina/análogos & derivados , Quitosana/química , Dermatite/prevenção & controle , Queratinócitos/metabolismo , Nanopartículas/administração & dosagem , Psoríase/prevenção & controle , Administração Tópica , Animais , Antineoplásicos/toxicidade , Antioxidantes/química , Antioxidantes/farmacologia , Catequina/química , Catequina/farmacologia , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Dermatite/etiologia , Proteínas Filagrinas , Humanos , Imiquimode , Queratinócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Psoríase/induzido quimicamente
20.
Mol Carcinog ; 57(10): 1267-1277, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29802724

RESUMO

We recently identified and characterized nummularic acid (NA) as a major chemical constituent of Fraxinus xanthoxyloides, a medicinal plant used for over hundred years in traditional medicine. In this study, we describe its potential anti-cancer activity using prostate cancer (PCa) cells as a model. We found that NA treatment (5-60 µM) significantly reduced the proliferation and colony formation capabilities of PCa DU145 and C4-2 cells in a time and dose dependent manner, reduced the migratory and invasive properties and increased apoptotic cell population. Mechanistically, we found that NA treatment to PCa cells resulted in a sustained activation of adenosine monophosphate-activated protein kinase (AMPK). NA simultaneously increased acetyl CoA carboxylase phosphorylation and decreased pS6 phosphorylation, the two major substrates of AMPK. Further, NA treatment significantly elevated the cellular ADP/ATP ratio and altered glycolytic rate. We further observed a reversible decrease in oxygen consumption rate in NA treated cells when compared to the control. Finally, we performed global untargeted metabolomics which showed that NA treatment alters PCa cell metabolism at multiple sites including glycolysis, tricarboxylic acid, and glutamine metabolism which supported our observation of a possible AMPK activation. In summary, we report NA as a novel small molecule activator of AMPK that alters cellular metabolism to induce energy crisis and ultimately cancer cell death. Because of its unique mechanism NA could be potentially applicable against other cancer types.


Assuntos
Proliferação de Células/efeitos dos fármacos , Metabolismo Energético/efeitos dos fármacos , Fraxinus/química , Plantas Medicinais/química , Triterpenos/farmacologia , Acetil-CoA Carboxilase/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Metabolômica/métodos , Estrutura Molecular , Peptídeos Cíclicos , Fosforilação/efeitos dos fármacos , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Triterpenos/química
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