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1.
J Virol ; 97(11): e0119423, 2023 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-37861336

RESUMO

IMPORTANCE: Severe COVID-19 and post-acute sequelae often afflict patients with underlying co-morbidities. There is a pressing need for highly effective treatment, particularly in light of the emergence of SARS-CoV-2 variants. In a previous study, we demonstrated that DCLK1, a protein associated with cancer stem cells, is highly expressed in the lungs of COVID-19 patients and enhances viral production and hyperinflammatory responses. In this study, we report the pivotal role of DCLK1-regulated mechanisms in driving SARS-CoV-2 replication-transcription processes and pathogenic signaling. Notably, pharmacological inhibition of DCLK1 kinase during SARS-CoV-2 effectively impedes these processes and counteracts virus-induced alternations in global cell signaling. These findings hold significant potential for immediate application in treating COVID-19.


Assuntos
Tratamento Farmacológico da COVID-19 , COVID-19 , Quinases Semelhantes a Duplacortina , Humanos , Quinases Semelhantes a Duplacortina/antagonistas & inibidores , Quinases Semelhantes a Duplacortina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , SARS-CoV-2/metabolismo , Transdução de Sinais , Replicação Viral/efeitos dos fármacos
2.
J Virol ; 96(17): e0096722, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35943255

RESUMO

Host factors play critical roles in SARS-CoV-2 infection-associated pathology and the severity of COVID-19. In this study, we systematically analyzed the roles of SARS-CoV-2-induced host factors, doublecortin-like kinase 1 (DCLK1), and S100A9 in viral pathogenesis. In autopsied subjects with COVID-19 and pre-existing chronic liver disease, we observed high levels of DCLK1 and S100A9 expression and immunosuppressive (DCLK1+S100A9+CD206+) M2-like macrophages and N2-like neutrophils in lungs and livers. DCLK1 and S100A9 expression were rarely observed in normal controls, COVID-19-negative subjects with chronic lung disease, or COVID-19 subjects without chronic liver disease. In hospitalized patients with COVID-19, we detected 2 to 3-fold increased levels of circulating DCLK1+S100A9+ mononuclear cells that correlated with disease severity. We validated the SARS-CoV-2-dependent generation of these double-positive immune cells in coculture. SARS-CoV-2-induced DCLK1 expression correlated with the activation of ß-catenin, a known regulator of the DCLK1 promoter. Gain and loss of function studies showed that DCLK1 kinase amplified live virus production and promoted cytokine, chemokine, and growth factor secretion by peripheral blood mononuclear cells. Inhibition of DCLK1 kinase blocked pro-inflammatory caspase-1/interleukin-1ß signaling in infected cells. Treatment of SARS-CoV-2-infected cells with inhibitors of DCLK1 kinase and S100A9 normalized cytokine/chemokine profiles and attenuated DCLK1 expression and ß-catenin activation. In conclusion, we report previously unidentified roles of DCLK1 in augmenting SARS-CoV-2 viremia, inflammatory cytokine expression, and dysregulation of immune cells involved in innate immunity. DCLK1 could be a potential therapeutic target for COVID-19, especially in patients with underlying comorbid diseases associated with DCLK1 expression. IMPORTANCE High mortality in COVID-19 is associated with underlying comorbidities such as chronic liver diseases. Successful treatment of severe/critical COVID-19 remains challenging. Herein, we report a targetable host factor, DCLK1, that amplifies SARS-CoV-2 production, cytokine secretion, and inflammatory pathways via activation of ß-catenin(p65)/DCLK1/S100A9/NF-κB signaling. Furthermore, we observed in the lung, liver, and blood an increased prevalence of immune cells coexpressing DCLK1 and S100A9, a myeloid-derived proinflammatory protein. These cells were associated with increased disease severity in COVID-19 patients. Finally, we used a novel small-molecule inhibitor of DCLK1 kinase (DCLK1-IN-1) and S100A9 inhibitor (tasquinimod) to decrease virus production in vitro and normalize hyperinflammatory responses known to contribute to disease severity in COVID-19.


Assuntos
COVID-19 , Quinases Semelhantes a Duplacortina , COVID-19/metabolismo , COVID-19/patologia , Calgranulina B/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Quinases Semelhantes a Duplacortina/antagonistas & inibidores , Quinases Semelhantes a Duplacortina/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Leucócitos Mononucleares/metabolismo , Quinolonas/farmacologia , SARS-CoV-2 , beta Catenina/metabolismo
3.
Molecules ; 28(4)2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36838589

RESUMO

Dasatinib (DAS), a narrow-therapeutic index drug, Bcr-Abl, and Src family kinases multitarget inhibitor have been approved for chronic myelogenous leukemia (CML) and Ph-positive acute lymphocytic leukemia (Ph+ ALL). Apigenin (APG) has a long history of human usage in food, herbs, health supplements, and traditional medicine, and it poses low risk of damage. The concomitant use of APG containing herbs/foods and traditional medicine may alter the pharmacokinetics of DAS, that probably lead to possible herb-drug interactions. The pharmacokinetic interaction of APG pretreatment with DAS in rat plasma following single and co-oral dosing was successfully deliberated using the UPLC-MS/MS method. The in vivo pharmacokinetics and protein expression of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 demonstrate that APG pretreatment has potential to drastically changed the DAS pharmacokinetics where escalation in the Cmax, AUC(0-t), AUMC(0-inf_obs), T1/2, Tmax, and MRT and reduction in Kel, Vd, and Cl significantly in rats pretreated with APG 40 mg/kg, thus escalating systemic bioavailability and increasing the rate of absorption via modulation of CYP3A2, Pgp-MDR1, and BCPR/ABCG2 protein expression. Therefore, the concomitant consumption of APG containing food or traditional herb with DAS may cause serious life-threatening drug interactions and more systematic clinical study on herb-drug interactions is required, as well as adequate regulation in herbal safety and efficacy.


Assuntos
Apigenina , Dasatinibe , Interações Ervas-Drogas , Animais , Ratos , Apigenina/farmacologia , Cromatografia Líquida , Dasatinibe/farmacocinética , Espectrometria de Massas em Tandem/métodos
4.
Saudi Pharm J ; 31(11): 101819, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37860687

RESUMO

Dasatinib (DAS) is a narrow therapeutic index drug and novel oral multitarget inhibitor of tyrosine kinase and approved for the first-line therapy for chronic myelogenous leukemia (CML) and Philadelphia chromosome (Ph + ) acute lymphoblastic leukemia (ALL). DAS, a known potent substrate of cytochrome (CYP) 3A, P-glycoprotein (Pgp) and breast cancer resistance protein (BCRP) and is subject to auto-induction. The dietary supplementation of sinapic acid (SA) or concomitant use of SA containing herbs/foods may alter the pharmacokinetics as well as pharmacodynamics of DAS, that may probably lead to potential interactions. Protein expression in rat hepatic and intestinal tissues, as well as the in vivo pharmacokinetics of DAS and the roles of CYP3 A2 and drug transporters Pgp-MDR1 and BCPR/ABCG2, suggested a likely interaction mechanism. The single dose of DAS (25 mg/kg) was given orally to rats with or without SA pretreatment (20 mg/kg p.o. per day for 7 days, n = 6). The plasma concentration of DAS was estimated by using Ultra-High-Performance Liquid Chromatography Mass spectrometry (UHPLC-MS/MS). The in vivo pharmacokinetics and protein expression study demonstrate that SA pretreatment has potential to alter the DAS pharmacokinetics. The increase in Cmax, AUC and AUMC proposes increase in bioavailability and rate of absorption via modulation of CYP3 A2, PgP-MDR1 and BCPR/ABCG2 protein expression. Thus, the concomitant use of SA alone or with DAS may cause serious life-threatening drug interactions.

5.
Molecules ; 27(6)2022 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-35335292

RESUMO

The genus Bidens a member of family Compositae, is widely documented as an ethno-medicinally important genus of plants. In the present study, anticancer potential of three ethno-medicinally important species i.e., B. bipinnata, B. biternata and B. pilosa were tested. For in-vitro evaluation, an MTT (Thiazolyl blue tetrazolium bromide) assay was performed against cervical cancer cells (HeLa), hepatocellular carcinoma (HepG), and adenocarcinoma human alveolar basal epithelial cells (A549). For in vivo evaluation, Artemia salina, Danio rerio, and Caenorhabditis elegans were used. Among all the tested extracts, the ethanol extract of B. biternata appeared to have highest anticancer activity, and the compounds responsible for this activity were identified to be Tris (2,4-di-tert-butylphenyl), 4-hydroxy-2,4'-dimethoxychalcone, and 2,4-di-tert-butylphenol. This is the first report of the isolation of Tris (2,4-di-tert-butylphenyl) phosphate from the genus Bidens and the first report of 4-hydroxy-2,4'-dimethoxychalcone and 2,4-di-tert-butylphenol from B. biternata. Among the isolated compounds, 4-hydroxy-2,4'-dimethoxychalcone showed the highest anticancer activity with an LD50 value of 236.7 µg/mL. Therefore, this compound carries promising potential for being established as a pharmaceutical for chemoprevention and chemotherapy.


Assuntos
Extratos Vegetais , Plantas , Cromatografia Líquida de Alta Pressão , Cromatografia Gasosa-Espectrometria de Massas , Células HeLa , Humanos
6.
J Biol Chem ; 291(7): 3254-67, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26698881

RESUMO

Hepatitis C virus (HCV) relies on host lipids and lipid droplets for replication and morphogenesis. The accumulation of lipid droplets in infected hepatocytes manifests as hepatosteatosis, a common pathology observed in chronic hepatitis C patients. One way by which HCV promotes the accumulation of intracellular lipids is through enhancing de novo lipogenesis by activating the sterol regulatory element-binding proteins (SREBPs). In general, activation of SREBPs occurs during cholesterol depletion. Interestingly, during HCV infection, the activation of SREBPs occurs under normal cholesterol levels, but the underlying mechanisms are still elusive. Our previous study has demonstrated the activation of the inflammasome complex in HCV-infected human hepatoma cells. In this study, we elucidate the potential link between chronic hepatitis C-associated inflammation and alteration of lipid homeostasis in infected cells. Our results reveal that the HCV-activated NLRP3 inflammasome is required for the up-regulation of lipogenic genes such as 3-hydroxy-3-methylglutaryl-coenzyme A synthase, fatty acid synthase, and stearoyl-CoA desaturase. Using pharmacological inhibitors and siRNA against the inflammasome components (NLRP3, apoptosis-associated speck-like protein containing a CARD, and caspase-1), we further show that the activation of the NLRP3 inflammasome plays a critical role in lipid droplet formation. NLRP3 inflammasome activation in HCV-infected cells enables caspase-1-mediated degradation of insulin-induced gene proteins. This subsequently leads to the transport of the SREBP cleavage-activating protein·SREBP complex from the endoplasmic reticulum to the Golgi, followed by proteolytic activation of SREBPs by S1P and S2P in the Golgi. Typically, inflammasome activation leads to viral clearance. Paradoxically, here we demonstrate how HCV exploits the NLRP3 inflammasome to activate SREBPs and host lipid metabolism, leading to liver disease pathogenesis associated with chronic HCV.


Assuntos
Proteínas de Transporte/metabolismo , Hepacivirus/fisiologia , Hepatócitos/virologia , Inflamassomos/metabolismo , Lipogênese , Proteína de Ligação a Elemento Regulador de Esterol 1/agonistas , Proteína de Ligação a Elemento Regulador de Esterol 2/agonistas , Proteínas Adaptadoras de Sinalização CARD , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/genética , Caspase 1/química , Caspase 1/genética , Caspase 1/metabolismo , Linhagem Celular Tumoral , Inibidores de Cisteína Proteinase/farmacologia , Proteínas do Citoesqueleto/antagonistas & inibidores , Proteínas do Citoesqueleto/genética , Proteínas do Citoesqueleto/metabolismo , Endopeptidases/química , Endopeptidases/metabolismo , Indução Enzimática/efeitos dos fármacos , Complexo de Golgi/efeitos dos fármacos , Complexo de Golgi/metabolismo , Complexo de Golgi/patologia , Complexo de Golgi/virologia , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/metabolismo , Hepatite C Crônica/patologia , Hepatite C Crônica/fisiopatologia , Hepatite C Crônica/virologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Inflamassomos/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Lipogênese/efeitos dos fármacos , Proteínas de Membrana/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Hepatopatia Gordurosa não Alcoólica/etiologia , Pró-Proteína Convertases/química , Pró-Proteína Convertases/metabolismo , Transporte Proteico/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Interferência de RNA , Serina Endopeptidases/química , Serina Endopeptidases/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
7.
Mol Cancer ; 16(1): 30, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28148261

RESUMO

BACKGROUND: More than 80% of intestinal neoplasia is associated with the adenomatous polyposis coli (APC) mutation. Doublecortin-like kinase 1 (Dclk1), a kinase protein, is overexpressed in colorectal cancer and specifically marks tumor stem cells (TSCs) that self-renew and increased the tumor progeny in Apc Min/+ mice. However, the role of Dclk1 expression and its contribution to regulating pro-survival signaling for tumor progression in Apc mutant cancer is poorly understood. METHODS: We analyzed DCLK1 and pro-survival signaling gene expression datasets of 329 specimens from TCGA Colon Adenocarcinoma Cancer Data. The network of DCLK1 and pro-survival signaling was analyzed utilizing the GeneMANIA database. We examined the expression levels of Dclk1 and other stem cell-associated markers, pro-survival signaling pathways, cell self-renewal in the isolated intestinal epithelial cells of Apc Min/+ mice with high-grade dysplasia and adenocarcinoma. To determine the functional role of Dclk1 for tumor progression, we knocked down Dclk1 and determined the pro-survival signaling pathways and stemness. We used siRNA technology to gene silence pro-survival signaling in colon cancer cells in vitro. We utilized FACS, IHC, western blot, RT-PCR, and clonogenic (self-renewal) assays. RESULTS: We found a correlation between DCLK1 and pro-survival signaling expression. The expression of Dclk1 and stem cell-associated markers Lgr5, Bmi1, and Musashi1 were significantly higher in the intestinal epithelial cells of Apc Min/+ mice than in wild-type controls. Intestinal epithelial cells of Apc Min/+ mice showed increased expression of pro-survival signaling, pluripotency and self-renewal ability. Furthermore, the enteroids formed from the intestinal Dclk1+ cells of Apc Min/+ mice display higher pluripotency and pro-survival signaling. Dclk1 knockdown in Apc Min/+ mice attenuates intestinal adenomas and adenocarcinoma, and decreases pro-survival signaling and self-renewal. Knocking down RELA and NOTCH1 pro-survival signaling and DCLK1 in HT29 and DLD1 colon cancer cells in vitro reduced the tumor cells' ability to self-renew and survive. CONCLUSION: Our results indicate that Dclk1 is essential in advancing intestinal tumorigenesis. Knocking down Dclk1 decreases tumor stemness and progression and is thus predicted to regulate pro-survival signaling and tumor cell pluripotency. This study provides a strong rationale to target Dclk1 as a treatment strategy for colorectal cancer.


Assuntos
Autorrenovação Celular/genética , Sobrevivência Celular/genética , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Animais , Análise por Conglomerados , Neoplasias do Colo/patologia , Modelos Animais de Doenças , Quinases Semelhantes a Duplacortina , Transição Epitelial-Mesenquimal/genética , Feminino , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Genes APC , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Mutação , Receptor Notch1/metabolismo
8.
Int J Hyperthermia ; 33(7): 779-784, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28540799

RESUMO

Self-controlled hyperthermia is a non-invasive technique used to kill or destroy cancer cells while preserving normal surrounding tissues. We have explored bulk magnetic Ni-Si and Ni-Al alloys as a potential thermoseeds. The structural, magnetic and magnetocaloric properties of the samples were investigated, including saturation magnetisation, Curie temperature (TC), and magnetic and thermal hysteresis, using room temperature X-ray diffraction and magnetometry. The annealing time, temperature and the effects of homogenising the thermoseeds were studied to determine the functional hyperthermia applications. The bulk Ni-Si and Ni-Al binary alloys have Curie temperatures in the desired range, 316 K-319 K (43 °C-46 °C), which is suitable for magnetic hyperthermia applications. We have found that TC strictly follows a linear trend with doping concentration over a wide range of temperature. The magnetic ordering temperature and the magnetic properties can be controlled through substitution in these binary alloys.


Assuntos
Alumínio , Hipertermia Induzida , Níquel , Silício , Ligas , Temperatura Alta , Fenômenos Magnéticos , Neoplasias/terapia
9.
J Sci Food Agric ; 97(13): 4408-4418, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28485471

RESUMO

BACKGROUND: Five maize inbred lines, 20 F1 diallel hybrids and two check genotypes were evaluated through genotype × environment interaction (GEI) and GGE biplot for earliness and yield traits at four locations. RESULTS: Genotype, environment and GEI showed highly significant differences for all the traits. In total sum of squares, environment and genotype played a primary role, followed by GEI. Larger effects of environment and genotype to total variation influence the earliness and yield traits. However, according to the GGE biplot, the first two principal components (PC1 and PC2) explained 95% of the variation caused by GEI. GGE biplot confirmed the differential response of genotypes across environments. F1 hybrid SWAJK-1 × FRHW-3 had better stability, with a good yield, and was considered an ideal genotype. F1 hybrid FRHW-2 × FRHW-1 showed more earliness at CCRI and Haripur, followed by PSEV3 × FRHW-2 and its reciprocal at Swat and Mansehra, respectively. F1 hybrids FRHW-1 × SWAJK-1, PSEV3 × SWAJK-1 and SWAJK-1 × FRHW-3 at Mansehra and Swat produced maximum grain yield, followed by SWAJK-1 × FRHW-1 and PSEV3 × FRHW-1 at Haripur and CCRI, respectively. CONCLUSION: Overall, maize genotypes showed early maturity in plain areas (CCRI and Haripur) but higher yield in hilly areas (Mansehra and Swat). © 2017 Society of Chemical Industry.


Assuntos
Interação Gene-Ambiente , Sementes/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Zea mays/genética , Clima , Ecossistema , Meio Ambiente , Genótipo , Fenótipo , Sementes/química , Sementes/genética , Zea mays/química
10.
Pak J Pharm Sci ; 29(1): 145-50, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26826828

RESUMO

Antibacterial and antifungal activities of different solvents extracted samples of Iris germinica were carried out through disc diffusion assay. For this purpose five different solvent extracts were prepared with two concentrations (1 and 2 mg disc(-1)) and their antimicrobial activity was tested using disc diffusion assay against eight pathogenic bacteria viz. Staphylococcus aureus, B. subtilis, Bacillus atrophaeus, Escherichia coli, Pseudomonas aeruginosa, Erwinia carotovara, Klebsiella pneumoniae, Salmonella typhi and one fungal specie (Candida albicans). Butanol and ethyl acetate fraction were more effective to control the growth of different pathogens followed by chloroform, hexane and aqueous fractions respectively. C. albicans, S. aureus E. carotovara, B. atrophaeus and E. coli were comparatively susceptible inhibited by all extracts of I. germinica compared with the rest of microbes. Maximum activity was shown by ethyl acetate extracted samples against B. atrophaeus followed by the same solvent against E. carotovara. Butanol extracted samples were effective against B. subtilis showing 62% reduction in growth at 1 or 2mg disc(-1) concentration. From these results it can be concluded that different solvent extracted samples from the leaves of I. germinica possess varying degree of antimicrobial against different micro-organisms and can be a good sources of antibiotics for the treatment of certain bacterial and fungal diseases.


Assuntos
Antibacterianos/farmacologia , Iris , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana
11.
Stem Cells ; 32(3): 822-7, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24123696

RESUMO

The role of Dclk1(+) tuft cells in the replacement of intestinal epithelia and reestablishing the epithelial barrier after severe genotoxic insult is completely unknown. Successful restoration requires precise coordination between the cells within each crypt subunit. While the mechanisms that control this response remain largely uncertain, the radiation model remains an exceptional surrogate for stem cell-associated crypt loss. Following the creation of Dclk1-intestinal-epithelial-deficient Villin-Cre;Dclk1(flox/flox) mice, widespread gene expression changes were detected in isolated intestinal epithelia during homeostasis. While the number of surviving crypts was unaffected, Villin-Cre;Dclk1(flox/flox) mice failed to maintain tight junctions and died at approximately 5 days, where Dclk1(flox/flox) mice lived until day 10 following radiation injury. These findings suggest that Dclk1 plays a functional role critical in the epithelial restorative response.


Assuntos
Células Epiteliais/metabolismo , Células Epiteliais/patologia , Deleção de Genes , Mucosa Intestinal/patologia , Proteínas Serina-Treonina Quinases/genética , Lesões por Radiação/patologia , Cicatrização , Animais , Quinases Semelhantes a Duplacortina , Regulação da Expressão Gênica , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Lesões por Radiação/metabolismo , Receptores Notch/genética , Receptores Notch/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo , Análise de Sobrevida , Irradiação Corporal Total
13.
Mol Cancer ; 13: 103, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24885928

RESUMO

BACKGROUND: Doublecortin-like kinase 1 (DCLK1) is emerging as a tumor specific stem cell marker in colorectal and pancreatic cancer. Previous in vitro and in vivo studies have demonstrated the therapeutic effects of inhibiting DCLK1 with small interfering RNA (siRNA) as well as genetically targeting the DCLK1+ cell for deletion. However, the effects of inhibiting DCLK1 kinase activity have not been studied directly. Therefore, we assessed the effects of inhibiting DCLK1 kinase activity using the novel small molecule kinase inhibitor, LRRK2-IN-1, which demonstrates significant affinity for DCLK1. RESULTS: Here we report that LRRK2-IN-1 demonstrates potent anti-cancer activity including inhibition of cancer cell proliferation, migration, and invasion as well as induction of apoptosis and cell cycle arrest. Additionally we found that it regulates stemness, epithelial-mesenchymal transition, and oncogenic targets on the molecular level. Moreover, we show that LRRK2-IN-1 suppresses DCLK1 kinase activity and downstream DCLK1 effector c-MYC, and demonstrate that DCLK1 kinase activity is a significant factor in resistance to LRRK2-IN-1. CONCLUSIONS: Given DCLK1's tumor stem cell marker status, a strong understanding of its biological role and interactions in gastrointestinal tumors may lead to discoveries that improve patient outcomes. The results of this study suggest that small molecule inhibitors of DCLK1 kinase should be further investigated as they may hold promise as anti-tumor stem cell drugs.


Assuntos
Antineoplásicos/farmacologia , Benzodiazepinonas/farmacologia , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinas/farmacologia , Antineoplásicos/química , Benzodiazepinonas/química , Sítios de Ligação , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Colágeno , Cultura em Câmaras de Difusão , Quinases Semelhantes a Duplacortina , Combinação de Medicamentos , Expressão Gênica , Vetores Genéticos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/química , Peptídeos e Proteínas de Sinalização Intracelular/genética , Isoenzimas/antagonistas & inibidores , Isoenzimas/química , Isoenzimas/genética , Laminina , Lentivirus/genética , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/química , Proteínas Serina-Treonina Quinases/genética , Proteoglicanas , Pirimidinas/química
14.
Am J Physiol Gastrointest Liver Physiol ; 306(5): G404-11, 2014 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-24368703

RESUMO

We have previously reported that doublecortin-like kinase 1 (Dclk1) is a putative intestinal stem cell (ISC) marker. In this report, we evaluated the use of Dclk1 as a marker of surviving ISCs in response to treatment with high-dose total body irradiation (TBI). Both apoptotic and mitotic Dclk1(+) cells were observed 24 h post-TBI associated with a corresponding loss of intestinal crypts observed at 84 h post-TBI. Although the Notch signaling pathway plays an important role in regulating proliferation and lineage commitment within the intestine, its role in ISC function in response to severe genotoxic injury is not yet fully understood. We employed the microcolony assay to functionally assess the effects of Notch inhibition with difluorophenacetyl-l-alanyl-S-phenylglycine t-butyl ester (DAPT) on intestinal crypt stem cell survival following severe (>8 Gy) radiation injury. Following treatment with DAPT, we observed a nearly 50% reduction in the number of surviving Dclk1(+) crypt epithelial cells at 24 h after TBI and similar reduction in the number of surviving small intestinal crypts at 84 h. These data indicate that inhibition of Notch signaling decreases ISC survival following radiation injury, suggesting that the Notch signaling pathway plays an important role in ISC-mediated crypt regeneration. These results also suggest that crypt epithelial cell Dclk1 expression can be used as one potential marker to evaluate the early survival of ISCs following severe radiation injury.


Assuntos
Regulação da Expressão Gênica/efeitos da radiação , Proteínas Serina-Treonina Quinases/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/efeitos da radiação , Irradiação Corporal Total/efeitos adversos , Animais , Biomarcadores , Quinases Semelhantes a Duplacortina , Células Epiteliais , Feminino , Mucosa Intestinal/citologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Notch/genética , Células-Tronco
15.
Nano Lett ; 13(8): 3476-81, 2013 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-23859076

RESUMO

We report on the low-temperature electrical transport properties of large area boron and nitrogen codoped graphene layers (BNC). The temperature dependence of resistivity (5 K < T < 400 K) of BNC layers show semiconducting nature and display a band gap which increases with B and N content, in sharp contrast to large area graphene layers, which shows metallic behavior. Our investigations show that the amount of B dominates the semiconducting nature of the BNC layers. This experimental observations agree with the density functional theory (DFT) calculations performed on BNC structures similar in composition to the experimentally measured samples. In addition, the temperature dependence of the electrical conductivity of these samples displays two regimes: at higher temperatures, the doped samples display an Arrhenius-like temperature dependence thus indicating a well-defined band gap. At the lowest temperatures, the temperature dependence of the conductivity deviates from activated behavior and displays a conduction mechanism consistent with Mott's two-dimensional (2D) variable range hopping (2D-VRH). The ability to tune the electronic properties of thin layers of BNC by simply varying the concentration of B and N will provide a tremendous boost for obtaining materials with tunable electronic properties relevant to applications in solid state electronics.

16.
J Virol ; 85(23): 12292-303, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21937640

RESUMO

Hepatitis C virus (HCV) infection is a prominent risk factor for the development of hepatocellular carcinoma (HCC). Similar to most solid tumors, HCCs are believed to contain poorly differentiated cancer stem cell-like cells (CSCs) that initiate tumorigenesis and confer resistance to chemotherapy. In these studies, we demonstrate that the expression of an HCV subgenomic replicon in cultured cells results in the acquisition of CSC traits. These traits include enhanced expression of doublecortin and CaM kinase-like-1 (DCAMKL-1), Lgr5, CD133, α-fetoprotein, cytokeratin-19 (CK19), Lin28, and c-Myc. Conversely, curing of the replicon from these cells results in diminished expression of these factors. The putative stem cell marker DCAMKL-1 is also elevated in response to the overexpression of a cassette of pluripotency factors. The DCAMKL-1-positive cells isolated from hepatoma cell lines by fluorescence-activated cell sorting (FACS) form spheroids in Matrigel. The HCV RNA abundance and NS5B levels are significantly reduced by the small interfering RNA (siRNA)-led depletion of DCAMKL-1. We further demonstrate that HCV replicon-expressing cells initiate distinct tumor phenotypes compared to the tumors initiated by parent cells lacking the replicon. This HCV-induced phenotype is characterized by high-level expression/coexpression of DCAMKL-1, CK19, α-fetoprotein, and active c-Src. The results obtained by the analysis of liver tissues from HCV-positive patients and liver tissue microarrays reiterate these observations. In conclusion, chronic HCV infection appears to predispose cells toward the path of acquiring cancer stem cell-like traits by inducing DCAMKL-1 and hepatic progenitor and stem cell-related factors. DCAMKL-1 also represents a novel cellular target for combating HCV-induced hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Perfilação da Expressão Gênica , Hepacivirus/patogenicidade , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteínas Serina-Treonina Quinases/metabolismo , RNA Viral/genética , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Quinases Semelhantes a Duplacortina , Feminino , Citometria de Fluxo , Hepacivirus/genética , Hepatite C/genética , Hepatite C/patologia , Hepatite C/virologia , Humanos , Técnicas Imunoenzimáticas , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Peptídeos e Proteínas de Sinalização Intracelular/genética , Queratina-19/genética , Queratina-19/metabolismo , Fígado/metabolismo , Fígado/virologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Análise de Sequência com Séries de Oligonucleotídeos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Reação em Cadeia da Polimerase em Tempo Real , Replicon , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transplante Heterólogo
17.
J Nanosci Nanotechnol ; 12(9): 7426-31, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23035488

RESUMO

The magnetic, magnetotransport, and magnetocaloric properties near compound phase transitions in Ni50Mn35In14Z (Z = In, Ge, Al), and Ni48Co2Mn35In15 Heusler alloys have been studied using VSM and SQUID magnetometers (at magnetic fields (H) up to 5 T), four-probe method (at H = 0.005-1.5 T), and an adiabatic magnetocalorimeter (for H changes up to deltaH = 1.8 T), respectively. The martensitic transformation (MT) is accompanied by large magnetoresistance (up to 70%), a significant change in resistivity (up to 200%), and a sign reversal of the ordinary Hall effect coefficient, all related to a strong change in the electronic spectrum at the MT. The field dependences of the Hall resistance are complex in the vicinity of the MT, indicating a change in the relative concentrations of the austenite and martensite phases at strong fields. Negative and positive changes in adiabatic temperatures of about -2 K and +2 K have been observed in the vicinity of MT and Curie temperatures, respectively, for deltaH = 1.8 T.

18.
Cancers (Basel) ; 14(11)2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35681791

RESUMO

Inflammation is an essential hallmark of cancer. Macrophages are key innate immune effector cells in chronic inflammation, parainflammation, and inflammaging. Parainflammation is a form of subclinical inflammation associated with a persistent DNA damage response. Inflammaging represents low-grade inflammation due to the dysregulation of innate and adaptive immune responses that occur with aging. Whether induced by infection, injury, or aging, immune dysregulation and chronic macrophage polarization contributes to cancer initiation through the production of proinflammatory chemokines/cytokines and genotoxins and by modulating immune surveillance. This review presents pre-clinical and clinical evidence for polarized macrophages as endogenous cellular carcinogens in the context of chronic inflammation, parainflammation, and inflammaging. Emerging strategies for cancer prevention, including small molecule inhibitors and probiotic approaches, that target macrophage function and phenotype are also discussed.

19.
J Biol Chem ; 285(8): 5713-25, 2010 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-20028973

RESUMO

Overexpression and activation of the c-Src protein have been linked to the development of a wide variety of cancers. The molecular mechanism(s) of c-Src overexpression in cancer cells is not clear. We report here an internal ribosome entry site (IRES) in the c-Src mRNA that is constituted by both 5'-noncoding and -coding regions. The inhibition of cap-dependent translation by m(7)GDP in the cell-free translation system or induction of endoplasmic reticulum stress in hepatoma-derived cells resulted in stimulation of the c-Src IRES activities. Sucrose density gradient analyses revealed formation of a stable binary complex between the c-Src IRES and purified HeLa 40 S ribosomal subunit in the absence of initiation factors. We further demonstrate eIF2-independent assembly of 80 S initiation complex on the c-Src IRES. These features of the c-Src IRES appear to be reminiscent of that of hepatitis C virus-like IRESs and translation initiation in prokaryotes. Transfection studies and genetic analysis revealed that the c-Src IRES permitted initiation at the authentic AUG351, which is also used for conventional translation initiation of the c-Src mRNA. Our studies unveiled a novel regulatory mechanism of c-Src synthesis mediated by an IRES element, which exhibits enhanced activity during cellular stress and is likely to cause c-Src overexpression during oncogenesis and metastasis.


Assuntos
Carcinoma Hepatocelular/metabolismo , Transformação Celular Neoplásica/metabolismo , Fator de Iniciação 2 em Eucariotos/metabolismo , Genes src , Iniciação Traducional da Cadeia Peptídica , Subunidades Ribossômicas Menores de Eucariotos/metabolismo , Regiões 5' não Traduzidas , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Transformação Celular Neoplásica/genética , Sistema Livre de Células/metabolismo , Células HeLa , Humanos , Metástase Neoplásica , Capuzes de RNA/genética , Capuzes de RNA/metabolismo , Subunidades Ribossômicas Menores de Eucariotos/genética , Estresse Fisiológico
20.
Saudi J Biol Sci ; 28(1): 347-352, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33424316

RESUMO

Genetic diversity play key role in the germplasm improvement which is directly correlated with the crop production. Various statistical techniques have been used to study diversity among different genotypes. Among these techniques multivariate is most frequently used one for the genetic association of genotypes. In the present study a total of 64 advance lines included one check cultivar were evaluated under the field conditions of Cereal Crop Research Institute, Pirsabaq Nowshera, Pakistan during September 2017. Data were recorded for nine different parameters. Multivariate analysis divided the total 64 genotypes into four groups. The first five PCs with Eigen values > 1 contributed 86.95% of the variability amongst genotypes. Characters with maximum values in PC1 were Spikelets spike-1 (SPPS) (0.732), spike length (SPL) (0.722) and biological yield (BY) (0.607), PC2 comprised of 100-grain weight (TGW) (0.605), grain yield (GY) (0.482) while days to heading (DH) (0.393), for PC3 major contributors were BY (0.550) and number of tillers meter square-1 (NTPS) (0.289), the contribution of PC4 were flag leaf area (FLA) (0.716) and SPL (0.298) and the maximum values for various traits in PC5 were SPPS (0.732), SPL (0.722) and BY (0.607). From the findings of present study best performing lines can be directly recommended for general cultivation or to be used in future breeding programs.

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