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1.
Integr Zool ; 17(2): 261-284, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33734569

RESUMO

The phylogeography of the Kaloula genus in East Asia is still poorly understood. One of the difficulties is the absence of fossils to corroborate molecular dating estimates. Here, we examined the mitochondrial structure of Kaloula spp. in East Asia and focused on the impact of glaciations on the northernmost species: Kaloula borealis. We determined the phylogenetic relationships, molecular dating, and genetic connectivity assessments within the genus from 1211 bp of concatenated mitochondrial 12S and 16S. The relaxed clock analyses reveal the emergence of Kaloula spp. common ancestor in East and Southeast Asia between the Eocene and Oligocene, c. 38.47 Ma (24.69-53.65). The genetic diversification of lineages then increased on the East Asian Mainland during the Lower Miocene, c. 20.10 (8.73-30.65), most likely originating from the vicariance and radiation triggered by the orogeny of the Qinghai-Tibetan Plateau. Later, the dispersal towards the North East Asian Mainland during the Upper Miocene drove the population diversification of K. borealis c. 9.01 Ma (3.66-15.29). Finally, the central mainland population became isolated following orogenesis events and diverged into K. rugifera during the Pliocene, c. 3.06 Ma (0.02-10.90). The combination of population genetic and barrier analyses revealed a significant genetic isolation between populations of Kaloula spp. matching with the massive Qinling-Daba Mountain chain located in south-central China. Finally, we highlight a young divergence within the Eastern Mainland population of K. borealis, possibly attributed to refugia in south eastern China from which populations later expanded.


Assuntos
Anuros , Refúgio de Vida Selvagem , Animais , Anuros/genética , Fósseis , Filogenia , Filogeografia
2.
World J Gastroenterol ; 26(23): 3249-3259, 2020 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32684739

RESUMO

BACKGROUND: The prevalence of nonalcoholic fatty liver disease (NAFLD) is significantly rising worldwide. Type-2 diabetes (T2D) is a major risk factor for NAFLD progression. AIM: To assess the association of commonly used medications to advanced fibrosis (AF) in patients with biopsy-proven NAFLD and T2D. METHODS: We used the International Classification of Disease 9th Revision Clinical Modification coding system to identify patients with T2D and included patients who underwent liver biopsy for suspected NAFLD between January 1, 2000 to December 31, 2015. We compared demographics, clinical characteristics, and differences in pattern of medication use in patients who had biopsy-proven AF to those without it. A univariate and multivariate analysis was performed to assess the association of different classes of medication with the presence of AF. RESULTS: A total of 1183 patients were included in the final analysis, out of which 32% (n = 381) had AF on liver biopsy. Mean age of entire cohort was 52 years and majority were females (65%) and Caucasians (85%). Among patients with AF, 51% were on oral hypoglycemics, 30% were on insulin, 66% were on antihypertensives and 27% were on lipid lowering agents for the median duration of 19 mo, 10 mo, 26 mo, and 24 mo respectively. Medications associated with decreased risk of AF included metformin, liraglutide, lisinopril, hydrochlorothiazide, atorvastatin and simvastatin while the use of furosemide and spironolactone were associated with higher prevalence of AF. CONCLUSION: In our cohort of T2D with biopsy proven NAFLD, the patients who were receiving metformin, liraglutide, lisinopril, hydrochlorothiazide, atorvastatin and simvastatin were less likely to have AF on biopsy, while patients who were receiving furosemide and spironolactone had a higher likelihood of having AF when they underwent liver biopsy. Future studies are needed to confirm these findings and to establish measures for prevention of NAFLD progression in patients with T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Metformina , Hepatopatia Gordurosa não Alcoólica , Biópsia , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Humanos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/epidemiologia , Cirrose Hepática/patologia , Masculino , Metformina/uso terapêutico , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/patologia
3.
Biol Blood Marrow Transplant ; 26(3): e55-e64, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31557532

RESUMO

Relapse after stem cell transplantation for Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL) remains a significant challenge. In this systematic review, we compare survival outcomes of second-generation tyrosine kinase inhibitors (TKIs) nilotinib and dasatinib with first-generation TKI imatinib when these agents are used after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in Ph+ ALL. In addition, we review the literature on TKI use to prevent relapse in patients who proceed to allo-HSCT beyond first complete response (>CR1). We performed database searches (inception to January 2018) using PubMed, Cochrane Library, and Embase. After exclusions, 17 articles were included in this analysis. Imatinib was used post-transplant either prophylactically or preemptively in 12 studies, 7 prospective studies and 5 retrospective studies. Overall survival (OS) for most prospective studies at 1.5 to 3 and 5 years ranged between 62% to 92% and 74.5% to 86.7%. Disease-free survival at 1.5 to 5 years was 60.4% to 92%. Additionally, imatinib failed to show survival benefit in patients who were >CR1 at the time of allo-HSCT. The cumulative OS for most retrospective studies using imatinib at 1 to 2 and 3 to 5 years was 42% to 100% and 33% to 40% respectively. Event-free survival at 1 to 2 and 3 to 5 years was 33.3% to 67% and 20% to 31% respectively. Dasatinib was used as maintenance treatment in 3 retrospective studies (n = 34). The OS for patients with Ph+ ALL using dasatinib as maintenance regimen after allo-HSCT at 1.4 to 3 years was 87% to 100% and disease-free survival at 1.4 to 3 years was 89% to 100%. Ninety-three percent of patients with minimal residual disease (MRD) positive status after allo-HSCT became MRD negative. Three prospective studies used nilotinib. In 2 studies where investigators studied patients with advanced chronic myeloid leukemia and Ph+ ALL, the cumulative OS and event-free survival at 7.5 months to 2 years were 69% to 84% and 56% to 84%, respectively. In the third study (n = 5) in patients with Ph+ ALL, nilotinib use resulted in OS at 5 years of 60%. Our review showed that use of TKIs (all generations) after allo-HSCT for patients in CR1 improved OS when given as a prophylactic or preemptive regimen. Limited data suggest that second-generation TKIs (ie, dasatinib) have a better OS, especially in patients with MRD-positive status. Imatinib did not improve OS in patients who were >CR1 at the time of allo-HSCT; for this population, no data were available with newer generation TKIs. The evaluation of survival benefit with newer generation TKIs and their efficacy in patients in >CR1 needs further study in large randomized clinical trials.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Estudos Prospectivos , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Prevenção Secundária , Transplante Homólogo
4.
World J Gastrointest Endosc ; 11(10): 491-503, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31798770

RESUMO

Esophageal cancer is a highly lethal disease and is the sixth leading cause of cancer related mortality in the world. The standard treatment is esophagectomy which is associated with significant morbidity and mortality. This led to development of minimally invasive, organ sparing endoscopic therapies which have comparable outcomes to esophagectomy in early cancer. These include endoscopic mucosal resection and endoscopic submucosal dissection. In early squamous cell cancer, endoscopic submucosal dissection is preferred as it is associated with cause specific 5-year survival rates of 100% for M1 and M2 tumors and 85% for M3 and SM1 tumors and low recurrence rates. In early adenocarcinoma, endoscopic resection of visible abnormalities is followed by ablation of the remaining flat Barrett's mucosa to prevent recurrences. Radiofrequency ablation is the most widely used ablation modality with others being cryotherapy and argon plasma coagulation. Focal endoscopic mucosal resection followed by radiofrequency ablation leads to eradication of neoplasia in 93.4% of patients and eradication of intestinal metaplasia in 73.1% of patients. Innovative techniques such as submucosal tunneling with endoscopic resection are developed for management of submucosal tumors of the esophagus. This review includes a discussion of various endoscopic techniques and their clinical outcomes in early squamous cell cancer, adenocarcinoma and submucosal tumors. An overview of comparison between esophagectomy and endoscopic therapy are also presented.

5.
Cureus ; 11(4): e4503, 2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31249765

RESUMO

Despite numerous advancements in diagnostics and treatment, lung cancer carries a high mortality rate. This is primarily attributable to the fact that the majority of patients present with stage III or IV disease and otherwise non-specific symptoms. In this article, we discuss a rare case of stage IV lung cancer presenting as supraventricular tachycardia secondary to cardiomediastinal involvement. Unfortunately, by the time the tumor had involved the mediastinum, surgical options were limited and treatment was largely palliative.

6.
Breast Cancer Res Treat ; 177(2): 307-323, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31175498

RESUMO

PURPOSE: More than 90% of the breast cancer deaths occur due to the metastasis of the cancer cells to secondary organ sites. Increased Glucose-regulated protein 78 (GRP78) expression is critical for epithelial-mesenchymal transition (EMT) and invasion in breast cancer resulting in poor patient survival outcomes. Therefore, there is an urgent need of potential inhibitors of GRP78 for the abrogation of invasion and metastasis in breast cancer. METHODS: We investigated the effect of IKM5 (2-(1-(1H-indol-3-yl)octyl)-3-hydroxy-6-(hydroxymethyl)-4H-pyran-4-one) (a novel Indolylkojyl methane analogue) on invasion abilities of human breast cancer cells employing invadopodia formation, Matrigel invasion assays, and mouse models for metastasis. The mechanism underlying the anti-invasive effect of IKM5 was examined through molecular docking, immunoblotting, immunocytochemistry, co-immunoprecipitation analysis, siRNA silencing, and sub-cellular fractionation studies. RESULTS: Treatment with IKM5 at its sub-toxic concentration (200 nM) suppressed invasion and invadopodia formation, and growth factor-induced cell scattering of aggressive human breast cancer MDA-MB-231, MDA-MB-468, and MCF7 cells. IKM5 spontaneously binds to GRP78 (Ki = 1.35 µM) and downregulates its expression along with the EMT markers MMP-2, Twist1, and Vimentin. Furthermore, IKM5 amplified the expression and nuclear translocation of tumor suppressor Par-4 to control NF-kB-mediated pro-EMT activities. Interestingly, IKM5 disrupts the interaction between GRP78 and TIMP-1 by inhibiting GRP78 in a Par-4-dependent manner. Moreover, IKM5 inhibited tumor growth and lung metastasis at a safe dose of 30 mg/kg/body weight. CONCLUSION: Our study warrants IKM5, a potential anticancer agent that can abrogate invasion and metastasis, suggesting its clinical development for the treatment of patients with advanced breast cancer.


Assuntos
Antineoplásicos/farmacologia , Proteínas de Choque Térmico/genética , Metano/farmacologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Doxorrubicina/farmacologia , Chaperona BiP do Retículo Endoplasmático , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Feminino , Proteínas de Choque Térmico/química , Proteínas de Choque Térmico/metabolismo , Humanos , Metaloproteinases da Matriz , Metano/análogos & derivados , Metano/química , Metano/farmacocinética , Camundongos , Modelos Biológicos , Modelos Moleculares , Conformação Molecular , Estrutura Molecular , Transporte Proteico , Relação Estrutura-Atividade , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Cureus ; 11(12): e6407, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31970037

RESUMO

Lambl's excrescences were first described in 1856 by a Bohemian physician, Vilém Dusan Lambl, and since then have gained widespread attention and controversy within the medical literature. Despite numerous case reports and observational studies, consensus on the significance and management of Lambl's excrescences remains sparse. We describe the case of a 48-year-old male who presented with recurrent embolic strokes. No underlying paroxysmal arrhythmia or inter-atrial shunt was identified, and the only pathological finding was a 1-mm aortic valve strand. We managed this patient successfully using a novel oral anticoagulant.

8.
Cell Death Differ ; 24(7): 1275-1287, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28498365

RESUMO

Twist1, a basic helix-loop-helix transcription factor is implicated as a key mediator of epithelial-mesenchymal transition (EMT) and metastatic dissemination in p53-deficient cancer cells. On the other hand, checkpoint kinase 2 (Chk2), a major cell cycle regulatory protein provides a barrier to tumorigenesis due to DNA damage response by preserving genomic stability of the cells. Here we demonstrate that Chk2 induction proficiently abrogates invasion, cell scattering and invadopodia formation ability of p53-mutated invasive cells by suppressing Twist1, indicating Chk2 confers vital role in metastasis prevention. In addition, ectopic Chk2, as well as its (Chk2) induction by natural podophyllotoxin analog, 4'-demethyl-deoxypodophyllotoxin glucoside (4DPG), strongly restrain Twist1 activity along with other mesenchymal markers, for example, ZEB-1, vimentin and Snail1, whereas the epithelial markers such as E-cadherin and TIMP-1 expression augmented robustly. However, downregulation of endogenous Chk2 by siRNA as well as Chk2 selective inhibitor PV1019 implies that 4DPG-mediated inhibition of Twist1 is Chk2-dependent. Further, mechanistic studies unveil that Chk2 negatively regulates Twist1 promoter activity and it (Chk2) interacts steadily with Snail1 protein to curb EMT. Strikingly, Chk2 overexpression triggers premature senescence in these cells with distinctive increase in senescence-associated ß-galactosidase (SA-ß-gal) activity, G2/M cell cycle arrest and induction of senescence-specific marker p21waf1/Cip1. Importantly, stable knockdown of Twist1 by shRNA markedly augments p21 expression, its nuclear accumulation, senescence-associated heterochromatin foci (SAHF) and amplifies the number of SA-ß-gal-positive cells. Moreover, our in vivo studies also validate that 4DPG treatment significantly abrogates tumor growth as well as metastatic lung nodules formation by elevating the level of phospho-Chk2, Chk2 and suppressing Twist1 activity in mouse mammary carcinoma model. In a nutshell, this report conceives a novel strategy of Twist1 suppression through Chk2 induction, which prevents metastatic dissemination and promotes premature senescence in p53-defective invasive cancer cells.


Assuntos
Senescência Celular , Quinase do Ponto de Checagem 2/metabolismo , Proteínas Nucleares/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Proteína 1 Relacionada a Twist/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Senescência Celular/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Glucosídeos/química , Glucosídeos/farmacologia , Humanos , Camundongos , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica , Proteínas Nucleares/genética , Podofilotoxina/análogos & derivados , Podofilotoxina/química , Podofilotoxina/farmacologia , Regiões Promotoras Genéticas/genética , Transcrição Gênica/efeitos dos fármacos , Proteína 1 Relacionada a Twist/genética
9.
Eur J Cell Biol ; 96(2): 164-171, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28216015

RESUMO

Multiple stresses are prevalent inside the tumor microenvironment rendering tumor growth, neighboring invasion and metastasis of the cancer cells to distant organs. NM23-H1 is the first metastasis suppressor gene identified and known to be implicated as an important regulator of stress-induced metastasis. Herein, we demonstrated that prototypical NM23-H1 expression diminished during hypoxia and serum starvation in Panc-1/MDA-MB-231 cells, but converse invasion patterns were obtained in these two diverse stresses. Supportingly, a compelling discrete difference in mRNA and protein levels of NM23-H1 was achieved in hypoxia as well as serum starvation. Knockdown of NM23-H1 activates EMT whereas the similar effects are subdued in serum starvation where NM23-H1 down-modulation prompted E-cadherin upregulation. Stable NM23-H1 expression augmented E-cadherin levels along with retardation in invadopodea formation and invasion. In hypoxia/serum starvation excess NM23-H1 effectively modulated the Twist1 promoter activity. Thus, differential regulation of NM23-H1 may corroborate/abrogate EMT depending on the nature of stress, tumor microenvironment and cellular context.


Assuntos
Nucleosídeo NM23 Difosfato Quinases/metabolismo , Neoplasias/enzimologia , Neoplasias/patologia , Diferenciação Celular/fisiologia , Hipóxia Celular/fisiologia , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Nucleosídeo NM23 Difosfato Quinases/genética , Metástase Neoplásica , Neoplasias/genética , Transfecção , Microambiente Tumoral
10.
Clin Exp Metastasis ; 33(8): 757-764, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27568374

RESUMO

Prostate apoptotic response 4 (Par-4) is coined as a therapeutic protein since owing to its diverse physiologically relevant properties, especially in the cancer perspective. Albeit, Par-4 expression is not restricted to any specific tissue/organ, apart from cell death promotion (due to challenging threats), the other biological role of Par-4 is convincingly emerging. In the recent years, several laboratories have intended to dissect the signaling or mechanisms involved in Par-4 activation to augment apoptosis cascades but new developments in Par-4 research have widened its therapeutic potential. One of these important avenues is the prevention of metastasis by pro-apoptotic Par-4. In this review, we will focus on the therapeutic perspective of Par-4 with a special reference to its (Par-4) virgin prospect of devastating metastasis control.


Assuntos
Proteínas Reguladoras de Apoptose/genética , Apoptose/genética , Metástase Neoplásica/genética , Proteínas Reguladoras de Apoptose/biossíntese , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Transdução de Sinais
11.
Age (Dordr) ; 38(3): 62, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27246693

RESUMO

Stress-induced premature senescence (SIPS) is quite similar to replicative senescence that is committed by cells exposed to various stress conditions viz. ultraviolet radiation (DNA damage), hydrogen peroxide (oxidative stress), chemotherapeutic agents (cytotoxic threat), etc. Here, we report that cristacarpin, a natural product obtained from the stem bark of Erythrina suberosa, promotes endoplasmic reticulum (ER) stress, leading to sub-lethal reactive oxygen species (ROS) generation and which eventually terminates by triggering senescence in pancreatic and breast cancer cells through blocking the cell cycle in the G1 phase. The majority of cristacarpin-treated cells responded to conventional SA-ß-gal stains; showed characteristic p21(waf1) upregulation along with enlarged and flattened morphology; and increased volume, granularity, and formation of heterochromatin foci-all of these features are the hallmarks of senescence. Inhibition of ROS generation by N-acetyl-L-cysteine (NAC) significantly reduced the expression of p21(waf1), confirming that the modulation in p21(waf1) by anti-proliferative cristacarpin was ROS dependent. Further, the elevation in p21(waf1) expression in PANC-1 and MCF-7 cells was consistent with the decrease in the expression of Cdk-2 and cyclinD1. Here, we provide evidence that cristacarpin promotes senescence in a p53-independent manner. Moreover, cristacarpin treatment induced p38MAPK, indicating the ROS-dependent activation of the MAP kinase pathway, and thus abrogates the tumor growth in mouse allograft tumor model.


Assuntos
Envelhecimento/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Dano ao DNA/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Estresse Oxidativo , Pterocarpanos/farmacologia , Envelhecimento/efeitos dos fármacos , Animais , Ciclo Celular/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Feminino , Citometria de Fluxo , Humanos , Immunoblotting , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
12.
Sci Rep ; 6: 18800, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26728896

RESUMO

The eukaryotic translation initiation factor 4E (eIF4E) is considered as a key survival protein involved in cell cycle progression, transformation and apoptosis resistance. Herein, we demonstrate that medicinal plant derivative 3-AWA (from Withaferin A) suppressed the proliferation and metastasis of CaP cells through abrogation of eIF4E activation and expression via c-FLIP dependent mechanism. This translational attenuation prevents the de novo synthesis of major players of metastatic cascades viz. c-FLIP, c-Myc and cyclin D1. Moreover, the suppression of c-FLIP due to inhibition of translation initiation complex by 3-AWA enhanced FAS trafficking, BID and caspase 8 cleavage. Further ectopically restored c-Myc and GFP-HRas mediated activation of eIF4E was reduced by 3-AWA in transformed NIH3T3 cells. Detailed underlying mechanisms revealed that 3-AWA inhibited Ras-Mnk and PI3-AKT-mTOR, two major pathways through which eIF4E converges upon eIF4F hub. In addition to in vitro studies, we confirmed that 3-AWA efficiently suppressed tumor growth and metastasis in different mouse models. Given that 3-AWA inhibits c-FLIP through abrogation of translation initiation by co-targeting mTOR and Mnk-eIF4E, it (3-AWA) can be exploited as a lead pharmacophore for promising anti-cancer therapeutic development.


Assuntos
Adenosina Trifosfatases/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Proteínas ras/metabolismo , Proteínas Adaptadoras de Transdução de Sinal , Animais , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Carcinoma de Ehrlich/genética , Carcinoma de Ehrlich/metabolismo , Carcinoma de Ehrlich/patologia , Proteínas de Transporte/metabolismo , Caspase 8/metabolismo , Proteínas de Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular/genética , ATPases Transportadoras de Cobre , Modelos Animais de Doenças , Fator de Iniciação 4E em Eucariotos/metabolismo , Fatores de Iniciação em Eucariotos , Humanos , Masculino , Camundongos , Metástase Neoplásica , Fosfoproteínas/metabolismo , Fosforilação , Biossíntese de Proteínas/efeitos dos fármacos , Transporte Proteico , Vitanolídeos/farmacologia , Receptor fas/metabolismo
13.
Mol Carcinog ; 55(5): 864-81, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-25969134

RESUMO

Here, we provide evidences that natural product derivative 3-azido Withaferin A (3-AWA) abrogated EMT and invasion by modulating ß-catenin localization and its transcriptional activity in the prostate as well as in breast cancer cells. This study, for the first time, reveals 3-AWA treatment consistently sequestered nuclear ß-catenin and augmented its cytoplasmic pool as evidenced by reducing ß-catenin transcriptional activity in these cells. Moreover, 3-AWA treatment triggered robust induction of pro-apoptotic intracellular Par-4, attenuated Akt activity and rescued Phospho-GSK3ß (by Akt) to promote ß-catenin destabilization. Further, our in vitro studies demonstrate that 3-AWA treatment amplified E-cadherin expression along with sharp downregulation of c-Myc and cyclin D1 proteins. Strikingly, endogenous Par-4 knock down by siRNA underscored 3-AWA mediated inhibition of nuclear ß-catenin was Par-4 dependent and suppression of Par-4 activity, either by Bcl-2 or by Ras transfection, restored the nuclear ß-catenin level suggesting Par-4 mediated ß-catenin regulation was not promiscuous. In vivo results further demonstrated that 3-AWA was effective inhibitor of tumor growth and immunohistochemical studies indicated that increased expression of total ß-catenin and decreased expression of phospho-ß-catenin and Par-4 in breast cancer tissues as compared to normal breast tissue suggesting Par-4 and ß-catenin proteins are mutually regulated and inversely co-related in normal as well as cancer condition. Thus, strategic regulation of intracellular Par-4 by 3-AWA in diverse cancers could be an effective tool to control cancer cell metastasis. Conclusively, this report puts forward a novel approach of controlling deregulated ß-catenin signaling by 3-AWA induced Par-4 protein.


Assuntos
Antineoplásicos Fitogênicos/administração & dosagem , Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias/tratamento farmacológico , Vitanolídeos/agonistas , beta Catenina/metabolismo , Animais , Antineoplásicos Fitogênicos/farmacologia , Apoptose , Linhagem Celular Tumoral , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Camundongos , Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Plantas Medicinais/química , Transdução de Sinais/efeitos dos fármacos
14.
ACS Med Chem Lett ; 6(10): 1071-4, 2015 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-26487914

RESUMO

The present work describes the anti-invasive effect of conjugate BC06, a novel conjugate of EPA, (2E,4E)-4-(benzo[d][1,3]dioxol-5-ylmethylene) hex-2-enoic acid with ß,ß-disubstituted-ß-amino acid, ß(3,3)-Pip-OH (2-(4-aminopiperidin-4-yl)acetic acid), in human pancreatic carcinoma. The conjugate BC06 inhibited invasion and migration of PANC-1 cells in wound healing, matrigel invasion, and gelatin degradation assays. Apart from suppressing PI3K/Akt/NF-kB signaling, which is involved in the up-regulation of matrix metalloproteinases, our study also demonstrated that dose-dependent treatment of BC06 results in the upregulation of TIMP-1 and E-cadherin expression. Further, BC06 was found to be inhibiting the metastatic ability of PANC-1 cells by reducing MMP-2 and MMP-9 expression. These findings suggest that EPA conjugate with ß(3,3)-Pip-OH, BC06, may be used as an anti-invasive agent against human pancreatic carcinoma.

15.
Chem Biol Interact ; 239: 1-11, 2015 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-26115782

RESUMO

The chemical investigation of the bioactive nonpolar fractions of Tanacetum gracile afforded two flavonoid analogues namely, 5-hydroxy-3,6,7,3',4'-pentamethoxyflavone (1) and 5,4'-dihydroxy-3,6,7,3',4'-tetramethoxyflavone (2) which were identical to the previously reported artemetin and chrysosplenetin respectively. The structure of the compounds was elucidated on the basis of spectroscopic evidences and they showed significant cytotoxic activity against human breast cancer cells (MCF-7 and T47D). Mechanism based study showed that the compounds modulated microtubule depolymerization by activating mitotic spindle checkpoint. Molecular docking at the colchicine binding pocket revealed that the compounds bind at α-ß interfacial site of tubulin, correlating binding interactions with probable inhibition mechanism. The study reveals important observations to generate improved flavonoids that leads to cell apoptosis. The compounds were also evaluated for absorption, metabolism and toxicity by online webserver admetSAR. The significant microtubule disassembling property and less toxicity paves way for consideration of the compounds as chemopreventive agents.


Assuntos
Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Flavonoides/farmacologia , Microtúbulos/efeitos dos fármacos , Tanacetum/química , Animais , Antineoplásicos Fitogênicos/toxicidade , Apoptose/efeitos dos fármacos , Sítios de Ligação , Barreira Hematoencefálica/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Colchicina/química , Colchicina/metabolismo , Colchicina/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Feminino , Flavonoides/química , Humanos , Células MCF-7/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Simulação de Acoplamento Molecular , Estrutura Molecular , Ratos , Espécies Reativas de Oxigênio/metabolismo , Moduladores de Tubulina/química , Moduladores de Tubulina/farmacologia
16.
Chem Biol Interact ; 232: 58-67, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25794856

RESUMO

Angiogenesis remain a critical procedure for tumor progression and malignancy. Anticancer agents targeting angiogenic cascades have been proved to be an effective strategy in the field of cancer therapeutics. The current study aims to explore the mechanistic prevention of angiogenesis and cancer cell proliferation by 1,1'-ß-d-glucopyranosyl-3,3'-bis(5-bromoindolyl)-octyl methane (NGD16), a novel N-glycosylated derivative of 3,3'-diindolylmethane (DIM). NGD16 suppressed the viability of prostate cancer (PC-3), pancreatic adenocarcinoma (MiaPaca-2), colorectal cancer (COLO-205) and human umbilical vein endothelial cells (HUVECs) effectively with IC50 values 0.8 µM, 2.8 µM, 5.3 µM and 2.5 µM respectively. Abrogation of angiogenesis by NGD16 was promising in in vivo mouse Matrigel plug assay as well as in ex vivo sprouting of rat thoracic aorta. At the molecular level, NGD16 inhibited the expression of glucose regulated protein, 78 kDa (GRP78), vascular endothelial growth factor receptor-2 (VEGFR2) and matrix metalloproteinase-9 (MMP-9) expression, the main mediators of angiogenesis and neovessel formation. Overexpression of GRP78 upregulated the expression of MMP-9 and VEGFR2 in PC-3 and HUVECs. Antibody blocking of GRP78 further potentiated NGD16 in attenuating angiogenesis through inhibition of MMP-9. NGD16 depicted its promising biodistribution profile in a pharmacokinetic study with 46.9% intraperitoneal bioavailability. Our findings suggest NGD16 is a potent inhibitor of neo-angiogenesis with a desirable pharmacokinetic profile, which can be taken forward in its development as an anticancer drug.


Assuntos
Proteínas de Choque Térmico/metabolismo , Indóis/farmacologia , Neovascularização Patológica/prevenção & controle , Inibidores da Angiogênese/farmacologia , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Chaperona BiP do Retículo Endoplasmático , Proteínas de Choque Térmico/genética , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Humanos , Indóis/química , Indóis/farmacocinética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Terapia de Alvo Molecular , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/patologia , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
17.
Chem Biol Interact ; 224: 100-7, 2014 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-25446499

RESUMO

We investigated the root of Podophyllum hexandrum as a potential source of lead bioactive metabolites with anticancer activity. The present study led to the isolation of six known aryltetralin-type lignans designated as 4'-demethyl-deoxypodophyllotoxin (1), podophyllotoxin (2), 4'-demethyl-podophyllotoxin (3), podophyllotoxin-4-O-ß-d-glucopyranoside (4), 4'-demethyl-deoxypodophyllotoxin-4-O-ß-d-glucopyranoside (5), 4'-demethyl-podophyllotoxin-4-O-ß-d-glucopyranoside (6), along with three known flavones Kaempferol (7), Quercetin (8), Astragalin (9) from the root of P. hexandrum. Compounds (1-9) exhibited the remarkable cytotoxic potential in diverse cancer cell lines. 5 therapeutic potential was extensively studied first time which exhibiting antiproliferative and ROS generating activity than its non-glycoside analogue 1. Furthermore, 5 augmented the apoptotic cascades in MCF-7 breast cancer cells, viz. nuclear condensation, membrane blebbing, probably by destabilizing the micro-tubular protein tubulin. Strikingly, our docking study and in vitro assays demonstrate that 5 binds to and modulate checkpoint kinase-2, a key cell cycle regulatory protein in normal and cancer cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Quinase do Ponto de Checagem 2/metabolismo , Glucosídeos/farmacologia , Podofilotoxina/análogos & derivados , Podophyllum/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Glucosídeos/química , Glucosídeos/isolamento & purificação , Humanos , Simulação de Acoplamento Molecular , Fosforilação , Podofilotoxina/química , Podofilotoxina/isolamento & purificação , Podofilotoxina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Moduladores de Tubulina/química , Moduladores de Tubulina/isolamento & purificação , Moduladores de Tubulina/farmacologia
18.
Front Biosci (Schol Ed) ; 5(1): 231-46, 2013 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-23277048

RESUMO

Acute drug resistance, intolerable side effects and non-specific target activation are the crucial barriers for efficient translational outcome of target directed cancer drug discovery. In the last five years, many of the bull's eye drugs failed to obtain FDA approval because of highly complicated mechanisms of the targeting receptors. These receptors include epidermal growth factor receptor (EGFR) and Insulin-like growth factor receptor 1 (IGF 1R), and are considered as pivotal signaling routes in highly transformed metastatic cancers. IGF 1R and EGFR families show homology in their structure and both the receptors share considerable crosstalk in their functions. An aberrant activation of these two pathways is often diagnosed among many cancer patients. Therefore, target based monoclonal antibodies and small molecule tyrosine kinase inhibitors, either in combination or co-targeting these two receptors may provide a new era of promising therapy and can help in remarkable progress among cancer patients.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Receptores ErbB/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Receptor IGF Tipo 1/antagonistas & inibidores , Animais , Receptores ErbB/metabolismo , Humanos , Terapia de Alvo Molecular , Metástase Neoplásica , Neoplasias/patologia , Inibidores de Proteínas Quinases/administração & dosagem , Receptor IGF Tipo 1/metabolismo , Transdução de Sinais/efeitos dos fármacos
19.
Eur J Med Chem ; 60: 490-6, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23354071

RESUMO

Chemical investigation of stem bark of Crataeva nurvala afforded 5,7-dimethoxy-3-phenyl-1-ethyl-1,4-dihydro-4-quinolone and a steroidal glycoside with unprecedented pentacyclic ring system named crataemine (1a) and crataenoside (2) respectively. The structures of the compounds were determined by spectroscopic analysis. A series of compounds with modification at position 1 of 1a (1a-1c) were prepared. All compounds were screened for cytotoxic activity against HeLa, PC-3 and MCF-7 cells. Only 1a and 2 showed potency against all three cells. Mechanism based study for activity of the compounds demonstrated that it could block the migration of more aggressive HeLa and PC-3 cells and prevent their colony formation ability as well. The compounds potentiated apoptosis in HeLa and PC-3 cells in a significant manner.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Capparaceae/química , Casca de Planta/química , Caules de Planta/química , Alcaloides/química , Alcaloides/isolamento & purificação , Alcaloides/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Células MCF-7 , Estrutura Molecular , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/isolamento & purificação , Triterpenos Pentacíclicos/farmacologia , Quinolonas/química , Quinolonas/isolamento & purificação , Quinolonas/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
20.
PLoS One ; 7(9): e44039, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22962598

RESUMO

BACKGROUND: Withaferin A, which is a naturally derived steroidal lactone, has been found to prevent angiogenesis and metastasis in diverse tumor models. It has also been recognized by different groups for prominent anti-carcinogenic roles. However, in spite of these studies on withanolides, their detailed anti-metastatic mechanism of action remained unknown. The current study has poised to address the machinery involved in invasion regulation by stable derivative of Withaferin A, 3-azido Withaferin A (3-azidoWA) in human cervical HeLa and prostate PC-3 cells. METHODS AND PRINCIPAL FINDINGS: Sub-toxic concentration of 3-azidowithaferin A (3-azido WA) inhibited cancer cell motility and invasion in wound healing and Boyden chamber invasion by suppressing MMP-2 activity in gelatin zymography and its expression has proved to be a major obstacle in chemo-sensitivity. We have uncovered a novel mechanism of 3-azidoWA induced extracellular pro-apoptotic candidate tumor suppressor Par-4 protein stimulation in conditioned media and also noticed a concomitant marked reduction in pAkt and pERK signaling by immunoblot analysis. Furthermore, our zymography results suggest 3-azidoWA induced MMP-2 inhibition was mediated through secretory Par-4. The inhibition of apoptosis by 3-azidoWA could not restore MMP-2 gelatinase activity. In addition to this, our in vivo animal experiments data showed 3-azidoWA abrogated neovascularisation in dose dependent manner in mouse Matrigel plug assay. CONCLUSION/SIGNIFICANCE: For this report, we found that 3-azidoWA suppressed motility and invasion of HeLa and PC-3 cells in MMP-2 dependent manner. Our in vitro result strongly suggests that sub-toxic doses of 3-azidoWA enhanced the secretion of extracellular Par-4 that abolished secretory MMP-2 expression and activity. Depletion of secretory Par-4 restored MMP-2 expression and invasion capability of HeLa and PC-3 cells. Further, our findings implied that 3-azidoWA attenuated internal phospho-ERK and phospho-Akt expression in a dose dependent manner might play a key role in inhibition of mouse angiogenesis by 3-azidoWA.


Assuntos
Antineoplásicos/farmacologia , Azidas/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Inibidores de Metaloproteinases de Matriz/farmacologia , Invasividade Neoplásica/prevenção & controle , Neovascularização Patológica/prevenção & controle , Receptores de Trombina/metabolismo , Vitanolídeos/farmacologia , Animais , Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Azidas/síntese química , Bioensaio , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Colágeno , Combinação de Medicamentos , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Laminina , Metaloproteinase 2 da Matriz/genética , Inibidores de Metaloproteinases de Matriz/síntese química , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Proteoglicanas , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores de Trombina/antagonistas & inibidores , Receptores de Trombina/genética , Transdução de Sinais , Vitanolídeos/síntese química
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