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1.
Microb Pathog ; 188: 106538, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38184177

RESUMEN

Because of uncontrolled use of antibiotics, emergence of multidrug-resistant Shigella species poses a huge potential of zoonotic transfer from poultry sector. With increasing resistance to current antibiotics, there is a critical need to explore antibiotic alternatives. Using a Shigella flexneri reference strain, we isolated a novel fPSFA phage after inducing with mitomycin C. The phage was found to be stable for wide ranges of temperature -20 °C-65 °C and pH 3 to 11. fPSFA shows a latent period that ranges from 20 to 30 min and generation times of 50-60 min. The genome analysis of phage reveals two major contigs of 23788 bp and 23285 bp with 50.16 % and 39.33 % G + C content containing a total of 80 CDS and 2 tRNA genes. The phage belongs to Straboviridae family and lacks any virulence or antimicrobial resistance gene, thus making it a suitable candidate for treatment of drug-resistant infections. To confirm lytic ability of novel phage, we isolated 54 multidrug-resistant Shigella species from thirty-five poultry fecal samples that shows multiple antibiotic resistance index ranging from 0.15 to 0.75 (from 3 Indian states). The fPSFA showed lytic activity against multidrug-resistant Shigella isolates (73.08 %) (MARI≥0.50). The wide host ranges of fPSFA phage demonstrate its potential to be used as a biocontrol agent.


Asunto(s)
Bacteriófagos , Shigella , Animales , Profagos/genética , Aves de Corral , Genoma Viral , Bacteriófagos/genética , Genómica , Antibacterianos/farmacología
2.
Microb Pathog ; 162: 105267, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34718127

RESUMEN

OmpU is a multimeric, cation selective outer membrane protein of Vibrio and related species that non-covalently interact with peptidoglycan layer. Interaction of OmpU with human host cells triggers signaling pathways to promote cytokine secretion, reactive oxygen species production, and caspase independent death in immune and epithelial cells. Non-choleric OmpU imparts resistance to antimicrobial peptides and induces actin cytoskeletal reorganization in the host cells. Further, OmpU isolated from Vibrio species elicits an immune response in several aquaculture hosts. Importantly, in-vivo studies using recombinant OmpU or OmpU derived mimotopes reveal a short-lasting immunity, and protection against Vibrio in the aquaculture sector. In conclusion, OmpU is a key adhesion protein and an important virulence factor for successful colonization of Vibrio species into hosts. This review article provides a broad overview of structural, regulatory, and functional mechanisms of OmpU in normal and disease states.


Asunto(s)
Vibriosis , Vibrio , Adhesinas Bacterianas , Péptidos Antimicrobianos , Proteínas de la Membrana Bacteriana Externa , Humanos , Vibriosis/veterinaria
3.
Bioorg Med Chem ; 72: 116976, 2022 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-36067627

RESUMEN

Colchicine binding site represent a crucial target for the anticancer drug development especially in view of emerging drug resistance from the currently available chemotherapeutics. A total of 16 novel 4-N-heterocyclic-2-aryl-6,7,8-trimethoxyquinazolines were synthesized and screened for antiproliferative and tubulin polymerization inhibition potential. The synthesized compounds were evaluated against MCF-7, HeLa and HT-29 cancer cell lines and normal cell line HEK-293 T. In the series, 2­aryl group with 4­bromophenyl substitution displayed IC50 values of 6.37 µM, 17.43 µM, 6.76 µM and 4­chlorophenyl substitution displayed IC50 values of 2.16 µM, 8.53 µM, 10.42 µM against MCF-7, HELA and HT29 cancer cell lines, respectively. In the mechanistic studies involving cell cycle analysis, apoptosis assay and JC-1 studies, both the lead compounds were found to induce mitochondria mediated apoptosis and lead molecule with 4­chlorophenyl substitution displayed significant tubulin polymerization inhibition activity. In the computation studies, lead molecule displayed significant binding affinites in the colchicine domain and showed good thermodynamic stability during 100 ns MD simulation studies. 4-N-Heterocyclic-2-aryl-6,7,8-trimethoxyquinazolines showed appreciable drug like characteristics and can be developed as potent anticancer agents.


Asunto(s)
Antineoplásicos , Quinazolinas , Moduladores de Tubulina , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular , Colchicina/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Células HEK293 , Humanos , Simulación del Acoplamiento Molecular , Polimerizacion , Quinazolinas/química , Relación Estructura-Actividad , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/química
4.
Bioorg Med Chem Lett ; 30(20): 127468, 2020 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-32768647

RESUMEN

A series of triphenyl substituted pyrimidines as analogous of colchicine and combretastatin A-4 was synthesized and evaluated for the antiproliferative potential. The compounds were screened against MDA-MB-231, HCT-116 and HT-29 cell lines using MTT assay. Most of the compounds displayed antiproliferative activity in low to sub micro molar concentration. Amongst the synthesized derivatives, compounds HK-2, HK-10 and HK-13 were found to be effective against all the three cancer cell lines. HK-2 exhibited IC50 values of 3.39 µM, 4.78 µM and 4.23 µM, HK-10 showed IC50 values of 0.81 µM, 5.89 µM, 4.96 µM and HK-13 showed IC50 values 3.24 µM, 4.93 µM and 4.73 µM against MDA-MB-231, HCT-116 and HT-29 cancer cell lines, respectively. HK-10 was found to be the most potent compound in the series with IC50 values of 0.81 µM against MDA-MB-231. In the cell cycle analysis, HK-2 and HK-10 showed cell arrest at G2/M phase of the cell cycle while HK-13 inhibited cell growth at the G1/G0 phase. All the three compounds showed cell death induced through apoptosis. In the docking studies, HK-2, HK-10 and HK-13 were found to fit well in the colchicine binding site of the tubulin. Some of the compounds in the current series were found to be promising against all the three cancer cell lines and may act as potent leads for further development.


Asunto(s)
Antineoplásicos/farmacología , Pirimidinas/farmacología , Moduladores de Tubulina/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Pirimidinas/síntesis química , Pirimidinas/química , Relación Estructura-Actividad , Tubulina (Proteína)/metabolismo , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/química
5.
J Biol Chem ; 292(41): 16833-16846, 2017 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-28842496

RESUMEN

Nischarin (Nisch) is a key protein functioning as a molecular scaffold and thereby hosting interactions with several protein partners. To explore the physiological importance of Nisch, here we generated Nisch loss-of-function mutant mice and analyzed their metabolic phenotype. Nisch-mutant embryos exhibited delayed development, characterized by small size and attenuated weight gain. We uncovered the reason for this phenotype by showing that Nisch binds to and inhibits the activity of AMP-activated protein kinase (AMPK), which regulates energy homeostasis by suppressing anabolic and activating catabolic processes. The Nisch mutations enhanced AMPK activation and inhibited mechanistic target of rapamycin signaling in mouse embryonic fibroblasts as well as in muscle and liver tissues of mutant mice. Nisch-mutant mice also exhibited increased rates of glucose oxidation with increased energy expenditure, despite reduced overall food intake. Moreover, the Nisch-mutant mice had reduced expression of liver markers of gluconeogenesis associated with increased glucose tolerance. As a result, these mice displayed decreased growth and body weight. Taken together, our results indicate that Nisch is an important AMPK inhibitor and a critical regulator of energy homeostasis, including lipid and glucose metabolism.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Metabolismo Energético , Gluconeogénesis , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Proteínas Quinasas Activadas por AMP/genética , Animales , Línea Celular , Glucosa/genética , Glucosa/metabolismo , Humanos , Receptores de Imidazolina , Péptidos y Proteínas de Señalización Intracelular/genética , Hígado/patología , Ratones , Ratones Mutantes , Mutación , Oxidación-Reducción , Unión Proteica
6.
Mol Cancer ; 17(1): 21, 2018 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-29415725

RESUMEN

BACKGROUND: During metastasis, tumor cells move through the tracks of extracellular matrix (ECM). Focal adhesions (FAs) are the protein complexes that link the cell cytoskeleton to the ECM and their presence is necessary for cell attachment. The tumor suppressor Nischarin interacts with a number of signaling proteins such as Integrin α5, PAK1, LIMK1, LKB1, and Rac1 to prevent cancer cell migration. Although previous findings have shown that Nischarin exerts this migratory inhibition by interacting with other proteins, the effects of these interactions on the entire FA machinery are unknown. METHODS: RT-PCR, Western Blotting, invadopodia assays, and immunofluorescence were used to examine FA gene expression and determine whether Nischarin affects cell attachment, as well as the proteins that regulate it. RESULTS: Our data show that Nischarin prevents cell migration and invasion by altering the expression of key focal adhesion proteins. Furthermore, we have found that Nischarin-expressing cells have reduced ability to attach the ECM, which in turn leads to a decrease in invadopodia-mediated matrix degradation. CONCLUSIONS: These experiments demonstrate an important role of Nischarin in regulating cell attachment, which adds to our understanding of the early events of the metastatic process in breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Adhesión Celular/genética , Receptores de Imidazolina/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Podosomas/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Matriz Extracelular/metabolismo , Femenino , Expresión Génica , Regulación de la Expresión Génica , Humanos , Receptores de Imidazolina/metabolismo , Integrinas/genética , Integrinas/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Modelos Biológicos , Podosomas/metabolismo
7.
Am J Pathol ; 186(4): 844-58, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26878213

RESUMEN

The actin cytoskeleton is a crucial regulator of the intestinal mucosal barrier, controlling the assembly and function of epithelial adherens and tight junctions (AJs and TJs). Junction-associated actin filaments are dynamic structures that undergo constant turnover. Members of the actin-depolymerizing factor (ADF) and cofilin protein family play key roles in actin dynamics by mediating filament severing and polymerization. We examined the roles of ADF and cofilin-1 in regulating the structure and functions of AJs and TJs in the intestinal epithelium. Knockdown of either ADF or cofilin-1 by RNA interference increased the paracellular permeability of human colonic epithelial cell monolayers to small ions. Additionally, cofilin-1, but not ADF, depletion increased epithelial permeability to large molecules. Loss of either ADF or cofilin-1 did not affect the steady-state morphology of AJs and TJs but attenuated de novo junctional assembly. The observed defects in AJ and TJ formation were accompanied by delayed assembly of the perijunctional filamentous actin belt. A total loss of ADF expression in mice did not result in a defective mucosal barrier or in spontaneous gut inflammation. However, ADF-null mice demonstrated increased intestinal permeability and exaggerated inflammation during dextran sodium sulfate-induced colitis. Our findings demonstrate novel roles for ADF and cofilin-1 in regulating the remodeling and permeability of epithelial junctions, as well as the role of ADF in limiting the severity of intestinal inflammation.


Asunto(s)
Cofilina 1/metabolismo , Destrina/metabolismo , Células Epiteliales/metabolismo , Inflamación/metabolismo , Mucosa Intestinal/metabolismo , Uniones Estrechas/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animales , Citoesqueleto/metabolismo , Destrina/genética , Humanos , Ratones , Proteínas de Microfilamentos/metabolismo , Permeabilidad
8.
Am J Physiol Gastrointest Liver Physiol ; 308(9): G745-56, 2015 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-25792565

RESUMEN

Adherens junctions (AJs) and tight junctions (TJs) are crucial regulators of the integrity and restitution of the intestinal epithelial barrier. The structure and function of epithelial junctions depend on their association with the cortical actin cytoskeleton that, in polarized epithelial cells, is represented by a prominent perijunctional actomyosin belt. The assembly and stability of the perijunctional cytoskeleton is controlled by constant turnover (disassembly and reassembly) of actin filaments. Actin-interacting protein (Aip) 1 is an emerging regulator of the actin cytoskeleton, playing a critical role in filament disassembly. In this study, we examined the roles of Aip1 in regulating the structure and remodeling of AJs and TJs in human intestinal epithelium. Aip1 was enriched at apical junctions in polarized human intestinal epithelial cells and normal mouse colonic mucosa. Knockdown of Aip1 by RNA interference increased the paracellular permeability of epithelial cell monolayers, decreased recruitment of AJ/TJ proteins to steady-state intercellular contacts, and attenuated junctional reassembly in a calcium-switch model. The observed defects of AJ/TJ structure and functions were accompanied by abnormal organization and dynamics of the perijunctional F-actin cytoskeleton. Moreover, loss of Aip1 impaired the apico-basal polarity of intestinal epithelial cell monolayers and inhibited formation of polarized epithelial cysts in 3-D Matrigel. Our findings demonstrate a previously unanticipated role of Aip1 in regulating the structure and remodeling of intestinal epithelial junctions and early steps of epithelial morphogenesis.


Asunto(s)
Uniones Adherentes/metabolismo , Células Epiteliales/metabolismo , Mucosa Intestinal/metabolismo , Proteínas de Microfilamentos/metabolismo , Uniones Estrechas/metabolismo , Citoesqueleto de Actina/metabolismo , Citoesqueleto de Actina/patología , Actomiosina/metabolismo , Uniones Adherentes/patología , Animales , Células CACO-2 , Polaridad Celular , Quistes/metabolismo , Quistes/patología , Células Epiteliales/patología , Regulación de la Expresión Génica , Humanos , Mucosa Intestinal/patología , Ratones , Proteínas de Microfilamentos/genética , Morfogénesis , Permeabilidad , Interferencia de ARN , Transducción de Señal , Uniones Estrechas/patología , Transfección
9.
J Biol Chem ; 288(22): 15495-509, 2013 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-23572524

RESUMEN

Biallelic inactivation of LKB1, a serine/threonine kinase, has been detected in 30% of lung adenocarcinomas, and inhibition of breast tumor growth has been demonstrated. We have identified the tumor suppressor, Nischarin, as a novel binding partner of LKB1. Our mapping analysis shows that the N terminus of Nischarin interacts with amino acids 44-436 of LKB1. Time lapse microscopy and Transwell migration data show that the absence of both Nischarin and LKB1 from an invasive breast cancer cell line (MDA-MB-231) enhances migration as measured by increased distance and speed of migrating cells. Our data suggest that this is a result of elevated PAK1 and LIMK1 phosphorylation. Moreover, the absence of Nischarin and LKB1 increased tumor growth in vivo. Consistent with this, the percentage of S phase cells was increased, as demonstrated by flow cytometry and enhanced cyclin D1. The absence of Nischarin and LKB1 also led to a dramatic increase in the formation of lung metastases. Our studies, for the first time, demonstrate functional interaction between LKB1 and Nischarin to inhibit cell migration and breast tumor progression. Mechanistically, we show that these two proteins together regulate PAK-LIMK-Cofilin and cyclin D1/CDK4 pathways.


Asunto(s)
Neoplasias de la Mama/metabolismo , Movimiento Celular , Células Epiteliales/metabolismo , Receptores de Imidazolina/metabolismo , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Glándulas Mamarias Humanas/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Quinasa 4 Dependiente de la Ciclina/genética , Quinasa 4 Dependiente de la Ciclina/metabolismo , Células Epiteliales/patología , Femenino , Humanos , Receptores de Imidazolina/genética , Péptidos y Proteínas de Señalización Intracelular/genética , Quinasas Lim/genética , Quinasas Lim/metabolismo , Glándulas Mamarias Humanas/patología , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Invasividad Neoplásica , Trasplante de Neoplasias , Proteínas Serina-Treonina Quinasas/genética , Trasplante Heterólogo , Proteínas Supresoras de Tumor/genética
10.
Cell Signal ; 113: 110953, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38084837

RESUMEN

BACKGROUND: Cancer Stem Cells (CSCs) have emerged as a critical mediator in recurrence and resistance in cancers. Kindlin-isoform (1 and 2) binds with cytoplasmic ß-tail of integrin and are essential co-activators of integrin function. Given their important function in regulating cancer hallmarks such as cell proliferation, invasion, migration, and metastasis, we hypothesize that it might play a critical role in CSC growth, survival, and self-renewal of colon cancer. MATERIALS AND METHODS: Using knockdown approaches, we inhibited Kindlin-2 expression in HCT116 and HT29 colon cancer cells. Extreme limiting dilution and self-renewal assay were performed to measure the role of Kindlin in colonic CSC. Standard methods such as qRT-PCR and western blotting were carried out to understand the signaling cascade by which Kindlin regulates CSC marker expression and downstream targets. RESULTS: Our data show isoform-specific upregulation of Kindlin-2 in colonic CSCs. The silencing of Kindlin-2 reduces colonosphere formation, decreases CSC size, and self-renewal marker genes such as CD-133, CXCR-4, LGR-5, and C-MYC. Kindlin-2 silencing reduces colonosphere proliferation, invasion, and migration of colonic CSCs. Mechanistically, Kindlin-2 silencing reduces the expression, and nuclear localization of ß-catenin, and decreases ß-catenin target genes such as C-MYC, cyclin D1, DKK-1, and Snail-1. CONCLUSION: Our study delineates the isoform-specific activity of Kindlin-2 in regulating Colonic CSC. Isoform-specific targeting of Kindlin-2 may be a novel strategy to tackle this devastating disease.


Asunto(s)
Neoplasias del Colon , beta Catenina , Humanos , beta Catenina/metabolismo , Línea Celular Tumoral , Proliferación Celular , Neoplasias del Colon/metabolismo , Integrinas/metabolismo , Células Madre Neoplásicas/metabolismo , Isoformas de Proteínas/metabolismo , Vía de Señalización Wnt/genética
11.
ACS Chem Neurosci ; 2024 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-38795037

RESUMEN

Alzheimer's disease is a complex neurological disorder linked with multiple pathological hallmarks. The interrelation of therapeutic targets assists in the enhancement of cognitive decline through interference with overall neuronal transmission. We have synthesized and screened various chromone derivatives as potential multitarget-directed ligands for the effective treatment of Alzheimer's disease. The synthesized compounds exhibited multipotent activity against AChE, BuChE, MAO-B, and amyloid ß aggregation. Three potent compounds, i.e., VN-3, VN-14, and VN-19 were identified that displayed remarkable activities against different targets. These compounds displayed IC50 values of 80 nM, 2.52 µM, and 140 nM against the AChE enzyme, respectively, and IC50 values of 2.07 µM, 70 nM, and 450 nM against the MAO-B isoform, respectively. VN-3 displayed potent activity against self-induced Aß1-42 aggregation with inhibition of 58.3%. In the ROS inhibition studies, the most potent compounds reduced the intracellular ROS levels up to 80% in SH-SY5Y cells at 25 µM concentration. The compounds were found to be neuroprotective and noncytotoxic even at a concentration of 25 µM against SH-SY5Y cells. In silico studies showed that the compounds were nicely accommodated in the active sites of the receptors along with thermodynamically stable orientations. Compound VN-19 exhibited a balanced multitargeting profile against AChE, BuChE, MAO-B, and Aß1-42 enzymes and was further evaluated for in vivo activities on the scopolamine-induced zebrafish model. VN-19 was found to ameliorate the cognitive decline in zebrafish brains by protecting them against scopolamine-induced neurodegeneration. Thus, VN-3, VN-14, and VN-19 were identified as potent multitarget-directed ligands with a balanced activity profile against different targets and can be developed as therapeutics for AD.

12.
Curr Cancer Drug Targets ; 23(4): 278-292, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36306454

RESUMEN

AIMS: Development of anticancer agents targeting tubulin protein. BACKGROUND: Tubulin protein is being explored as an important target for anticancer drug development. Ligands binding to the colchicine binding site of the tubulin protein act as tubulin polymerization inhibitors and arrest the cell cycle in the G2/M phase. OBJECTIVE: Synthesis and screening of benzotriazole-substituted 2-phenyl quinazolines as potential anticancer agents. METHODS: A series of benzotriazole-substituted quinazoline derivatives have been synthesized and evaluated against human MCF-7 (breast), HeLa (cervical) and HT-29 (colon) cancer cell lines using standard MTT assays. RESULTS: ARV-2 with IC50 values of 3.16 µM, 5.31 µM, 10.6 µM against MCF-7, HELA and HT29 cell lines, respectively displayed the most potent antiproliferative activities in the series while all the compounds were found non-toxic against HEK293 (normal cells). In the mechanistic studies involving cell cycle analysis, apoptosis assay and JC-1 studies, ARV-2 and ARV-3 were found to induce mitochondria-mediated apoptosis. CONCLUSION: The benzotriazole-substituted 2-phenyl quinazolines have the potential to be developed as potent anticancer agents.


Asunto(s)
Antineoplásicos , Tubulina (Proteína) , Humanos , Tubulina (Proteína)/metabolismo , Relación Estructura-Actividad , Polimerizacion , Células HEK293 , Proliferación Celular , Simulación del Acoplamiento Molecular , Ensayos de Selección de Medicamentos Antitumorales , Quinazolinas/farmacología , Antineoplásicos/farmacología , Antineoplásicos/química
13.
Methods Mol Biol ; 2303: 765-777, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34626421

RESUMEN

Cancer stem-like cells (CSC) have been implicated in resistance to conventional chemotherapy as well as invasion and metastasis resulting in tumor relapse in majority of epithelial cancers including colorectal cancer. Hence, targeting CSC by small molecules is likely to improve therapeutic outcomes. Glycosaminoglycans (GAGs) are long linear polysaccharide molecules with varying degrees of sulfation that allows specific GAG-protein interaction which plays a key role in regulating cancer hallmarks such as cellular growth, angiogenesis, and immune modulation. However, identifying selective CSC-targeting GAG mimetic has been marred by difficulties associated with isolating and enriching CSC in vitro. Herein, we discuss two distinct methods, spheroid growth and EMT-transformed cells, to enrich CSC and set up medium- and high-throughput screen to identify selective CSC-targeting agents.


Asunto(s)
Neoplasias , Células Madre Neoplásicas , Línea Celular Tumoral , Proliferación Celular , Transición Epitelial-Mesenquimal , Humanos
14.
Mol Cancer ; 10: 84, 2011 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-21752283

RESUMEN

BACKGROUND: Although integrins have been implicated in the progression of breast cancer, the exact mechanism whereby they exert this regulation is clearly not understood. To understand the role of integrins in breast cancer, we examined the expression levels of several integrins in mouse breast cancer cell lines by flow cytometry and the data were validated by Western and RT-PCR analysis. The importance of integrins in cell migration and cell invasion was examined by in vitro assays. Further the effect of integrins on metastasis was investigated by in vivo experimental metastasis assays using mouse models. RESULTS: Integrin α5 subunit is highly expressed in the nonmetastatic cell line 67NR and is significantly low in the highly invasive cell line 4T1. In contrast, expression levels of integrin α6 subunit are high in 4T1 cells and low in 67NR cells. In vitro data indicated that overexpression of α5 subunit and knockdown of α6 integrin subunit inhibited cell proliferation, migration, and invasion. Our in vivo findings indicated that overexpression of integrin α5 subunit and knockdown of α6 subunit decreased the pulmonary metastasis property of 4T1 cells. Our data also indicated that overexpression of alpha 5 integrin subunit and suppression of alpha6 integrin subunit inhibited cells entering into S phase by up-regulating p27, which results in downregulation of cyclinE/CDK2 complexes, This suggests that these integrins regulate cell growth through their effects on cell-cycle-regulated proteins. We also found that modulation of these integrins upregulates E2F, which may induce the expression of chk1 to regulate cdc25A/cyclin E/CDK2/Rb in a feedback loop mechanism. CONCLUSION: This study indicates that Integrin α5 subunit functions as a potential metastasis suppressor, while α6 subunit functions as a metastasis promoter. The modulation of integrins reduces cdc25 A, another possible mechanism for downregulation of CDK2. Taken together we demonstrate a link between integrins and the chk1-cdc25-cyclin E/CDK2-Rb pathway.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma/patología , Ciclo Celular/genética , Factores de Transcripción E2F/genética , Integrina alfa5/fisiología , Integrina alfa6/fisiología , Proteínas Quinasas/genética , Proteína de Retinoblastoma/genética , Animales , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Carcinoma/genética , Carcinoma/metabolismo , Ciclo Celular/fisiología , Línea Celular Tumoral , Quinasa 1 Reguladora del Ciclo Celular (Checkpoint 1) , Factores de Transcripción E2F/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica/fisiología , Integrina alfa5/genética , Integrina alfa5/metabolismo , Integrina alfa6/genética , Integrina alfa6/metabolismo , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Proteínas Quinasas/metabolismo , Subunidades de Proteína/fisiología , Proteína de Retinoblastoma/metabolismo , Transducción de Señal/genética , Transducción de Señal/fisiología
15.
Int J Cancer ; 126(6): 1283-90, 2010 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-19877123

RESUMEN

MicroRNAs have emerged as a novel class of noncoding RNAs that regulate gene expression at the post-translational level in almost every biological event. A large body of evidence indicates that microRNAs regulate the expression of different genes that play an important role in cancer cell invasion, migration and metastasis. In this review, we briefly describe the role of various miRNAs in invasion, migration and metastasis which are essential steps during cancer progression.


Asunto(s)
MicroARNs/genética , Neoplasias/genética , Neoplasias/patología , Animales , Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Modelos Biológicos , Invasividad Neoplásica , Metástasis de la Neoplasia , Proteínas Supresoras de Tumor/genética
16.
Turk J Chem ; 44(6): 1623-1641, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33488258

RESUMEN

Quinoline moiety is an important scaffold in the field of drug discovery and drug development, with a wide range of pharmacological activities. Quinoline derivatives are potent inhibitors for reverse transcriptase, which is responsible for the conversion of single-stranded viral RNA into double-stranded viral DNA.In the present study, we have designed and synthesized 2 series, namely pyrazoline and pyrimidine containing quinoline derivatives as non nucleoside reverse transcriptase inhibitors (NNRTIs). Eleven compounds were synthesized and characterized by 1H and 13C NMR and mass spectrophotometry. The synthesized compounds were also docked on an HIV reverse transcriptase binding site (PDB: 4I2P); most of these compounds showed good binding interactions with the active domain of the receptor. Most of the compounds displayed a docking score higher than those of standard drugs. Among the synthesized quinoline derivatives, compound 4 exhibited the highest docking score (-10.675).

17.
Biochem Biophys Res Commun ; 384(1): 6-11, 2009 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-19379710

RESUMEN

Disruption of cell-cell adhesion, which is essential for the maintenance of epithelial plasticity and is mediated by a class of proteins called cadherins, is an initial event in the progression of cancer. Cadherins are Ca(2+)-dependent transmembrane proteins that are associated with actin via other cytoplasmic proteins. Disruption of cell-cell adhesion during cancer progression is an important event during cancer initiation and metastasis. E-cadherin, one of the most widely studied tumor suppressors in breast cancer, belongs to a family of calcium-dependent cell adhesion molecules. Various signaling molecules and transcription factors regulate the expression of E-cadherin. Loss of E-cadherin has been reported to induce epithelial-mesenchymal transition in several cancers. This review highlights recent advances in defining the mechanisms that regulate E-cadherin expression in breast cancer.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Cadherinas/genética , Regulación Neoplásica de la Expresión Génica , Adhesión Celular/genética , Humanos , Transcripción Genética
18.
Cancer Res ; 79(9): 2152-2166, 2019 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-30635277

RESUMEN

Exosomes are small extracellular microvesicles that are secreted by cells when intracellular multivesicular bodies fuse with the plasma membrane. We have previously demonstrated that Nischarin inhibits focal adhesion formation, cell migration, and invasion, leading to reduced activation of focal adhesion kinase. In this study, we propose that the tumor suppressor Nischarin regulates the release of exosomes. When cocultured on exosomes from Nischarin-positive cells, breast cancer cells exhibited reduced survival, migration, adhesion, and spreading. The same cocultures formed xenograft tumors of significantly reduced volume following injection into mice. Exosomes secreted by Nischarin-expressing tumors inhibited tumor growth. Expression of only one allele of Nischarin increased secretion of exosomes, and Rab14 activity modulated exosome secretions and cell growth. Taken together, this study reveals a novel role for Nischarin in preventing cancer cell motility, which contributes to our understanding of exosome biology. SIGNIFICANCE: Regulation of Nischarin-mediated exosome secretion by Rab14 seems to play an important role in controlling tumor growth and migration.See related commentary by McAndrews and Kalluri, p. 2099.


Asunto(s)
Neoplasias de la Mama , Exosomas , Animales , Línea Celular Tumoral , Movimiento Celular , Receptores de Imidazolina , Péptidos y Proteínas de Señalización Intracelular , Ratones
19.
Oncotarget ; 7(51): 84608-84622, 2016 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-27705927

RESUMEN

Heparan sulfate (HS) plays a role in the majority of essential hallmarks of cancer, yet its ability to modulate self-renewal, especially of cancer stem cells (CSCs), remains unknown. We have discovered that a non-anticoagulant HS hexasaccharide (HS06) sequence, but not other shorter or longer sequences, selectively inhibited CSC self-renewal and induced apoptosis in colorectal, pancreatic, and breast CSCs suggesting a very general phenomenon. HS06 inhibition of CSCs relied upon early and sustained activation of p38α/ß mitogen activated protein kinase (MAPK) but not other MAPKs family members i.e. ERK and JNK. In contrast, polymeric HS induced exactly opposite changes in MAPK activation and failed to inhibit CSCs. In fact, TCF4 signaling, a critical regulator of CSC self-renewal, was inhibited by HS06 in a p38 activation dependent fashion. In conclusion, HS06 selectively inhibits CSCs self-renewal by causing isoform specific activation of p38MAPK to inhibit TCF4 signaling. These observations on chain length-induced specificity carry major mechanistic implications with regard to HS in cancer biology, while also presenting a novel paradigm for developing novel anti-CSC hexasaccharides that prevent cancer relapse.Heparan sulfate (HS) of specific length, i.e., hexasaccharide (HS06), but not longer or shorter sequences, selectively inhibit cancer stem cells (CSCs) through isoform specific activation of p38 mitogen-activated protein kinase. These findings will have major implication for developing chemical probes to decipher complex signaling events that govern cancer stem cells. Additionally, there are direct implications for designing glycosaminoglycan based cancer therapies to selectively target CSCs that escape killing by traditional chemotherapy threatening cancer relapse.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias Colorrectales/metabolismo , Heparitina Sulfato/metabolismo , Células Madre Neoplásicas/fisiología , Neoplasias Pancreáticas/metabolismo , Autorrenovación de las Células , Descubrimiento de Drogas , Activación Enzimática , Femenino , Regulación Neoplásica de la Expresión Génica , Heparitina Sulfato/química , Humanos , Transducción de Señal , Factor de Transcripción 4/metabolismo , Células Tumorales Cultivadas , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
20.
Methods Mol Biol ; 1229: 529-41, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25325978

RESUMEN

Cancer stem-like cells (CSC) have been implicated in resistance to conventional chemotherapy as well as invasion and metastasis resulting in tumor relapse in majority of epithelial cancers including colorectal cancer. Hence, targeting CSC by small molecules is likely to improve therapeutic outcomes. Glycosaminoglycans (GAGs) are long linear polysaccharide molecules with varying degrees of sulfation that allows specific GAG-protein interaction which plays a key role in regulating cancer hallmarks such as cellular growth, angiogenesis, and immune modulation. However, identifying selective CSC-targeting GAG mimetic has been marred by difficulties associated with isolating and enriching CSC in vitro. Herein, we discuss two distinct methods, spheroid growth and EMT-transformed cells, to enrich CSC and set up medium- and high-throughput screen to identify selective CSC-targeting agents.


Asunto(s)
Antineoplásicos/farmacología , Evaluación Preclínica de Medicamentos/métodos , Células Madre Neoplásicas/patología , Biomarcadores de Tumor/metabolismo , Cadherinas/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Citometría de Flujo , Técnicas de Silenciamiento del Gen , Ensayos Analíticos de Alto Rendimiento , Humanos , Lentivirus/metabolismo , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/patología , Transducción Genética
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