RESUMO
Triple-negative breast cancer (TNBC) is characterized by the complex tumor microenvironment (TME) consisting of an abundance of mesenchymal stem cells (MSCs), which is known to facilitate epithelial-to-mesenchymal transition (EMT). The development of single-cell genomics is a powerful method for defining the intricate genetic landscapes of malignancies. In this study, we have employed single-cell RNA sequencing (scRNA-seq) to dissect the intra-tumoral heterogeneity and analyze the single-cell transcriptomic landscape to detect rare consequential cell subpopulations of significance. The scRNA-seq analysis of TNBC and Normal patient derived samples revealed that EMT markers and transcription factors were most upregulated in MSC population. Further, exploration of gene expression analysis among TNBC and Normal patient-derived MSCs ascertained the role of SQSTM1/P62 and Wnt/ß-catenin in TNBC progression. Wnt/ß-catenin and Wnt/PCP signaling pathways are prominent contributors of EMT, stemness, and cancer stem cell (CSC) properties of TNBC. SQSTM1/P62 cooperates with the components of the Wnt/PCP signaling pathway and is critically involved at the interface of autophagy and EMT. Moreover, siRNA targeting SQSTM1/P62 and inhibitor of Wnt/ß-catenin (FH535) in conjunction was used to explore molecular modification of EMT and stemness markers. Although SQSTM1/P62 is not crucial for cell survival, cytotoxicity assay revealed synergistic interaction between the siRNA/inhibitor. Modulation of these important pathways helped in reduction of expression of genes and proteins contributing to CSC properties. Gene and protein expression analysis revealed the induction of EMT to MET. Moreover, co-treatment resulted in inactivation of non-canonical Wnt VANGL2-JNK signaling axis. The synergistic impact of inhibition of SQSTM1/P62 and Wnt/ß-catenin signaling facilitates the development of a potential therapeutic regimen for TNBC.
Assuntos
Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas , Proteína Sequestossoma-1 , Análise de Célula Única , Neoplasias de Mama Triplo Negativas , Via de Sinalização Wnt , Feminino , Humanos , beta Catenina/metabolismo , beta Catenina/genética , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Proteína Sequestossoma-1/metabolismo , Proteína Sequestossoma-1/genética , Análise de Célula Única/métodos , Transcriptoma/genética , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Neoplasias de Mama Triplo Negativas/metabolismo , Microambiente Tumoral/genética , Via de Sinalização Wnt/genéticaRESUMO
Altered energy metabolism is an emerging hallmark of cancer and plays a pivotal in cell survival, proliferation, and biosynthesis. In a rapidly proliferating cancer, energy metabolism acts in synergism with epithelial-to-mesenchymal transition (EMT), enabling cancer stemness, dissemination, and metastasis. In this study, an interconnected functional network governing energy metabolism and EMT signaling pathways was targeted through the concurrent inhibition of IR, ITGB1, and CD36 activity. A novel multicomponent MD simulation approach was employed to portray the simultaneous inhibition of IR, ITGB1, and CD36 by a 2:1 combination of Pimozide and Ponatinib. Further, in-vitro studies revealed the synergistic anticancer efficacy of drugs against monolayer as well as tumor spheroids of breast cancer cell lines (MCF-7 and MDA-MB-231). In addition, the combination therapy exerted approximately 40% of the apoptotic population and more than 1.5- to 3-fold reduction in the expression of ITGB1, IR, p-IR, IRS-1, and p-AKT in MCF-7 and MDA-MB-231 cell lines. Moreover, the reduction in fatty acid uptake, lipid droplet accumulation, cancer stemness, and migration properties were also observed. Thus, targeting IR, ITGB1, and CD36 in the interconnected network with the combination of Pimozide and Ponatinib represents a promising therapeutic approach for breast cancer.
Assuntos
Neoplasias da Mama , Antígenos CD36 , Metabolismo Energético , Transição Epitelial-Mesenquimal , Integrina beta1 , Humanos , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Integrina beta1/metabolismo , Antígenos CD36/metabolismo , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Feminino , Metabolismo Energético/efeitos dos fármacos , Células MCF-7 , Imidazóis/farmacologia , Piridazinas/farmacologia , Proliferação de Células/efeitos dos fármacos , Linhagem Celular Tumoral , Apoptose/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacosRESUMO
Triple-negative breast cancer (TNBC) is considered the most aggressive form of breast cancer owing to the negative expression of targetable bioreceptors. Epithelial to mesenchymal transition (EMT) associated with metastatic abilities is its critical feature. As an attempt to target TNBC, nanotechnology was utilised to augment the effects of drug repurposing. Concerning that, a combination therapeutic module was structured with one of the aspects being a repurposed antihistamine, promethazine hydrochloride loaded PLGA nanoparticles. The as-synthesized nanoparticles were 217 nm in size and fluoresced at 522 nm, rendering them suitable for theranostic applications too. The second feature of the module was a common histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA), used as a form of pre-treatment. Experimental studies demonstrated efficient cellular internalisation and significant innate anti-proliferative potential. The use of SAHA sensitised the cells to the drug loaded nanoparticle treatment. Mechanistic studies showed increase in ROS generation, mitochondrial dysfunction followed by apoptosis. Investigations into protein expression also revealed reduction of mesenchymal proteins like vimentin by 1.90-fold; while increase in epithelial marker like E-Cadherin by 1.42-fold, thus indicating an altered EMT dynamics. Further findings also provided better insight into the benefits of SAHA potentiated targeting of tumor spheroids that mimic solid tumors of TNBC. Thus, this study paves the avenue to a more rational translational validation of combining nanotherapeutics with drug repurposing. .
RESUMO
The study of drop deformation in response to various stresses has long piqued the interest of several academics. The deformation behavior of cells, drug carriers, and even drug particles moving via microcapillaries inside the human body can be modeled using a viscoelastic drop model. A drop breakup study can also provide better design guidance for nanocarriers that can deliver on-demand burst drug releases at specific cancer sites. Thus, we attempted to investigate the deformation and breakup of a shear-thinning finitely extensible nonlinear elastic-peterlin (FENE-P) drop moving through the constricted microchannel. The computational simulation suggested that drop deformation and breakup can be manipulated by varying of parameters like channel confinement, Deborah number, solvent viscosity ratio, viscosity ratio, and capillary number. We attempted to find the critical capillary number for initiation of drop breakup. Observations from present study will give valuable insights into deformation and breakup patterns of drug carriers inside constricted microcapillaries. The simulations of the two-phase viscoelastic dropâNewtonian matrix system were performed on an open-source solver, Basilisk.
RESUMO
Governing protein-protein interaction networks are the cynosure of cell signaling and oncogenic networks. Multifarious processes when aligned with one another can result in a dysregulated output which can result in cancer progression. In the current research, one such network of proteins comprising VANG1/SCRIB/NOS1AP, which is responsible for cell migration, is targeted. The proteins are modeled using in-silico approaches, and the interaction is visualized utilizing protein-protein docking. Designing drugs for the convoluted protein network can serve as a challenging task that can be overcome by fragment-based drug designing, a recent game-changer in the computational drug discovery strategy for protein interaction networks. The model is exposed to the extraction of hotspots, also known as the restrained regions for small molecular hits. The hotspot regions are subjected to a library of generated fragments, which are then recombined and rejoined to develop small molecular disruptors of the macromolecular assemblage. Rapid screening methods using pharmacokinetic tools and 2D interaction studies resulted in four molecules that could serve the purpose of a disruptor. The final validation is executed by long-range simulations of 100 ns and exploring the stability of the complex using several parameters leading to the emergence of two novel molecules VNS003 and VNS005 that could be used as the disruptors of the protein assembly VANG1/SCRIB/NOS1AP. Also, the molecules were explored as single protein targets approbated via molecular docking and 100 ns molecular dynamics simulation. This concluded VNS003 as the most suitable inhibitor module capable of acting as a disruptor of a macromolecular assembly as well as acting on individual protein chains, thus leading to the primary hindrance in the formation of the protein interaction complex.
Assuntos
Descoberta de Drogas , Mapas de Interação de Proteínas , Simulação de Acoplamento Molecular , Ligação Proteica , Descoberta de Drogas/métodos , ProteínasRESUMO
Protein-bound paclitaxel has been developed clinically as one of the most successful chemotherapy drugs for the treatment of a wide variety of cancers. However, these medications, due to their nanoscale properties, may often induce capillary blocking while migrating through minute blood vessels. Considering the detrimental impact of this restriction, we investigated the transport of protein-bound paclitaxel, Paclicad, in a 7 µm microchannel mimicking the identical mechanical confinement of the blood capillaries. The drug was reported to migrate through a constricted microchannel without obstruction at a solution flow rate of 20-50 µL/h. The onset of an agglomeration site was observed at higher flow rates of 70-90 µL/h, while complete capillary obstruction was observed at 100 µL/h. The mobility of the particles was also calculated, and the results suggested that the presence of varying cross-sections affects the mobility of the drug particles. The trajectory of the particle migration was observed to be less tortuous at the higher flow rate, but the tortuous nature appeared to increase with the presence of agglomeration sites in the flow field. The experimental results were also compared with the computational model of the drug particle. The drug particle was modeled both as Newtonian and as an FENE-P viscoelastic drop. The drop interface tracking was done by the VOF method using the open source software Basilisk. The particle displacement was better estimated by both the FENE-P and Newtonian model at a flow rate of 30 µL/h, while deviation was observed at a flow rate of 50 µL/h. The FENE-P model was observed to show higher deformation than the Newtonian model at both flow rates. The experimental results provided better insight into the agglomeration tendency of Paclicad, migrating through a constricted microchannel at higher flow rates. The numerical model could be further employed to understand the more complex intravenous transport of drugs.
Assuntos
Antineoplásicos , Neoplasias , Paclitaxel Ligado a Albumina , Capilares , Humanos , Paclitaxel/farmacologiaRESUMO
Multifunctional drug delivery systems are the centerpiece of effective chemotherapeutic strategies. Herein, we report the synthesis of an acetazolamide-linked cyanine-3-based NIR-responsive fluorescent macrocyclic amphiphile that self-assembled into spherical nanostructures in the aqueous medium via a J-aggregation pattern. The amphiphile shows various favorable properties of lipids. The photocleavage of the strained dioxacycloundecine ring induces spherical to nanotubular self-assembly with concomitant release of an encapsulated anticancer drug, doxorubicin (Dox), in a controlled manner. The CA-IX targeted amphiphile also showed lower cytotoxicity, effective cellular uptake, and Dox delivery to the model carcinoma cells.
Assuntos
Acetazolamida , Antineoplásicos , Antineoplásicos/química , Antineoplásicos/farmacologia , Doxorrubicina/química , Doxorrubicina/farmacologia , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , LipídeosRESUMO
Cytokines are a group of glycoprotein signaling mediators, which play essential roles in maintaining several complex physiological functions of our body. TNFα is such a pleiotropic cytokine, which involves maintaining a plethora of immune responses. Initially, TNFα is synthesized as a 26 kDa full-length transmembrane form, which is enzymatically cleaved to produce the soluble circulating 17 kDa TNFα. Although the anti-cancer potential of soluble TNFα was discovered more than a century back, its dual ability to promote tumor, posed a major hindrance in finding its acceptance as a proper anti-cancer molecule. In contrast, the membrane-tethered tmTNFα holds the potential of tumor regression without initiating cell proliferation. The membrane-tethered form of TNFα is the physiological precursor of soluble TNFα that remains biologically active and is capable of initiating signaling cascades after binding with the TNFα receptors- TNFR I and TNFR II. In this review, we emphasize on the basic biology and molecular aspects of tmTNFα for its anti-cancer potential.
Assuntos
Apoptose/imunologia , Citotoxicidade Imunológica/imunologia , Proteínas de Membrana/imunologia , Neoplasias/imunologia , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/imunologia , Humanos , Proteínas de Membrana/metabolismo , Neoplasias/metabolismo , Neoplasias/patologia , Ligação Proteica , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores Tipo II do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
The self-organized transport and delivery of reactive liquids without spillage or loss of activity have been among the most daunting challenges for a long time. In this direction, we employ the concept of forming "liquid marbles" (LMs) to encapsulate and transport reactive hydrogen peroxide (H2O2) coated with functional microparticles. For example, peroxide marbles coated with a toner ink display remote-controlled magnetotactic movement inside a fluidic medium, thus overcoming the weaknesses associated with use of the bare droplets. Interestingly, in such a scenario, the coating of the marbles could also be removed or reformed by bringing the magnet towards or away from the marble. In this way, this process could ensure an on-demand remotely guided coating on the peroxide droplet or its removal. The liquid marbles carrying peroxide solutions are found to preserve the activity of the peroxide and exhibit a low evaporation rate compared with the uncoated peroxide fuel. Interestingly, oil droplets floating on the water could be recovered by introducing the armoured LMs into water under magnetic guidance. Further, the functionalized marbles could be employed as suicide bags for the on-demand delivery of reactive materials in targeted locations. Preliminary research on the antibacterial activity of such liquid marbles has proven to be effective in bacterial killing, which may create new avenues for emerging antibacterial and antibiofilm applications. Finally, such functionalized LMs have been employed to investigate the effects of surface charge on attachment of recombinant Escherichia coli bacteria expressing green fluorescent protein and monitoring the real-time imaging of bacterial death attached to the marble surface.
RESUMO
A Cu(I)-mediated cascade cyclization/annulation of unprotected o-alkynylanilines with maleimides in one pot is developed. The protocol offers sequential formation of one C-N and two C-C bonds to deliver fused benzo[a]carbazoles having free NH skeletons. The annulated products display fluorescence emission in the range of 485-502 nm with a large Stokes shift and fluorescence lifetime of â¼17 ns. The annulated 3aa displays AEE behavior in the ethanol/hexane system and possesses marigold-flower-like morphology at the aggregated state. Cell viability assays enumerate biocompatible AEEgens, while their high intracellular fluorescence depicts cell imaging applicability.
Assuntos
Carbazóis , Cobre , Catálise , Ciclização , MaleimidasRESUMO
Development of nanocomposites as drug delivery vectors is a burgeoning field of research. However, the usage of such newly invented nanomatrices are often limited by the shortcomings associated with the testing of their real-life efficacy. Many drugs fail because a monolayer framework ofin vitrocell line screening method does not adequately mimic thein vivothree-dimensional microenvironments. In this direction, the study unveils the development of a continuous flow microreactor wherein the cellulose acetate nanoparticles (CANPs) with varying sizes are prepared before encapsulating them with an anticancer drug-doxorubicin (DOX). Subsequently, anin vitromicrofluidic drug delivery model has been introduced in which the HeLa cells specific to cervical cancer is treated with the DOX encapsulated CANPs-DOX@CANPs. Thereafter, the transport of the drugs from the fluidic to cellular environment, their transport inside the cell, and the real-time kinetics of the cancer cell apoptosis have been analyzed systematically to uncover the real-time efficacy and cytotoxic effects of the nanocomposite. Interestingly, experiments reveal, (i) â¼89.4% DOX loading on the nanocomposite owing to a facile electrostatic interaction, (ii) a pH-dependent controlled release of drug during the transport with the cancer cells, and (iii) cell apoptosis after the diffused inoculation of the drug. A mathematical model has been developed to emulate the drug transport from the surrounding fluid to the cancer cells. Experiments together with the mathematical model uncover that the kinetics of cancer cell death is limited by the reaction at the cell-nucleus. The microfluidic model has shown significant potential to be translated as a useful tool for the real-time and on-demandin vitroscreening of the cancer drugs.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Doxorrubicina/química , Portadores de Fármacos/química , Nanopartículas/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Celulose/análogos & derivados , Celulose/química , Doxorrubicina/metabolismo , Doxorrubicina/farmacologia , Células HeLa , Humanos , Cinética , MicrofluídicaRESUMO
Soluble TNFα, a member of TNF superfamily attributes dual roles in apoptosis and cell proliferation whereas its precursor transmembrane TNFα (tmTNFα) has potential for tumor reduction without initiating proliferation. In this perspective, we recombinantly expressed functional tmTNFα and explored its potential in cell growth inhibition. While structural characterizations of purified tmTNFα revealed integrity of the protein, cell viability assays demonstrated significant antiproliferative effect on HepG2 (IC50: 36 nM) and HeLa (IC50: 23 nM) cells. Mechanistic insights into mode of cell death unveiled G1 arrest in HepG2 and G2/M arrest in HeLa cells accompanied with disruption of mitochondrial membrane potential and activation of executioner caspases. Subsequent, flow cytometry based assays resulted confirmatory evidence of apoptosis after treatment with the recombinant protein. Additionally, effect of the recombinant protein on 3D tumor spheroids was explored, which rendered reduction in tumor size due to cell death as evident from confocal microscopy studies. Effectiveness of the tmTNFα in 2D monolayer as well as in complex 3D spheroids demonstrate the therapeutic significance of the protein, featuring recombinant tmTNFα as an attractive option for cancer therapeutics in days to come.
Assuntos
Precursores de Proteínas/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Apoptose/efeitos dos fármacos , Caspases/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Células HeLa , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Fator de Necrose Tumoral alfa/metabolismo , Fatores de Necrose Tumoral/metabolismoRESUMO
Effective delivery of a photosensitizer with the ability to trace its eventual progress forms an important aspect in photodynamic therapy (PDT). Further, the delivery mechanism might require possessing the ability to traverse through the complex mucus barrier that offers retention of therapeutic molecules. In this work, gold nanocluster (Au NC)-embedded mucin nanoparticles were synthesized by a rapid green synthetic procedure for application as nanocarriers and to achieve image-guided PDT. The mucin-based nanocarrier exhibited excellent biocompatibility toward normal cells (HEK 293T). The photosensitizer methylene blue (MB) was loaded onto these Au NC-mucin nanoparticles (NPs). HeLa cancer cells were treated with MB-loaded Au NC-mucin nanoparticles under irradiation of 640 nm light. The cell viability assay revealed that the viability of HeLa cells was reduced to 50% after treatment with MB-loaded Au NC-mucin NPs under 640 nm irradiation. The luminescence exhibited by Au NCs in the nanocarrier was applied for tracking the delivery of MB inside the HeLa cells using confocal microscopy. The flow cytometry assays elucidated the mechanism of cell death.
Assuntos
Portadores de Fármacos , Nanopartículas Metálicas , Azul de Metileno , Neoplasias , Fotoquimioterapia , Fármacos Fotossensibilizantes , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Ouro/química , Ouro/farmacologia , Células HEK293 , Células HeLa , Humanos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , Azul de Metileno/química , Azul de Metileno/farmacologia , Mucinas/química , Mucinas/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologiaRESUMO
The therapeutic application of recombinant proteins is limited due to their inherent structural complexity. Additionally, screening of therapeutic potential of protein products requires an appropriate testing platform to achieve biological relevance. Fabrication of three dimensional cultures bridges the gap between in vitro based monolayer cultures and clinical applications. In this perspective, glioblastoma U-87 MG and breast cancer MCF7 spheroids were generated to assess the therapeutic prospect of recombinant PTEN protein. PTEN bound to silver nanoclusters was encapsulated within PEG coating, which resulted in fabrication of spherical nanocarriers named as PTEN-nanocomposites. Internalization of PTEN-nanocomposites in the spheroids was confirmed by confocal microscopy. Upon uptake, PTEN-nanocomposites led to modulation of cyclins and apoptosis gene regulators culminating in cell cycle arrest and reduced cell viability as confirmed by calcein-AM/PI dual staining and alamar blue assay. Further, combination of tamoxifen and PTEN-nanocomposites on U-87 MG spheroids resulted in two-fold reduction of drug dosage. The study revealed that the monolayer culture results translated to the 3D culture as well, however higher dose of the recombinant PTEN was required for the spheroid system. The anti-proliferative role of PTEN-nanocomposites in a complex 3D environment augments its biological implication and paves the way for recombinant PTEN based therapeutic applications.
Assuntos
PTEN Fosfo-Hidrolase/farmacologia , Polietilenoglicóis/química , Esferoides Celulares/citologia , Tamoxifeno/farmacologia , Técnicas de Cultura de Células , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células MCF-7 , Nanopartículas Metálicas , Microscopia Confocal , Nanocompostos , PTEN Fosfo-Hidrolase/química , PTEN Fosfo-Hidrolase/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Esferoides Celulares/efeitos dos fármacos , Esferoides Celulares/metabolismoRESUMO
We demonstrate the feasibility of a self-propelling mushroom motor, namely a 'logibot', as a functional unit for the construction of a host of optimized binary logic gates. Emulating the chemokinesis of unicellular prokaryotes or eukaryotes, the logibots made stimuli responsive conditional movements at varied speeds towards a pair of acid-alkali triggers. A series of integrative logic operations and cascaded logic circuits, namely, AND, NAND, NOT, OR, NOR, and NIMPLY, have been constructed employing the decisive chemotactic migrations of the logibot in the presence of the pH gradient established by the sole or coupled effects of acid (HCl-catalase) and alkali (NaOH) drips inside a peroxide bath. The imposed acid and/or alkali triggers across the logibots were realized as inputs while the logic gates were functionally reconfigured to several operational modes by varying the pH of the acid-alkali inputs. The self-propelling logibot could rapidly sense the external stimuli, decide, and act on the basis of intensities of the pH triggers. The impulsive responses of the logibots towards and away from the external acid-alkali stimuli were interpreted as the potential outputs of the logic gates. The external stimuli responsive self-propulsion of the logibots following different logic gates and circuits can not only be an eco-friendly alternative to the silicon-based computing operations but also be a promising strategy for the development of intelligent pH-responsive drug delivery devices.
Assuntos
Biomimética/métodos , Quimiotaxia , Lógica , Microbiologia , Agaricus/metabolismoRESUMO
A paradigm shift toward fusion proteins to render multiple functionalities and applications on a single platform has been incurred in enzyme based diagnosis. Herein, we report development and systematic characterizations of glutathione-S-transferase (GST) and human lactate dehydrogenase A (hLDHA) in a fusion protein (GST-hLDHA) to achieve functional activities of GST and hLDHA simultaneously. The GST-pGEX-4T-2 vector system was used for cloning and purification of hLDHA, utilizing the affinity based interaction between GST and GSH in column chromatography. Bacterially purified protein was subjected to the Western blot analysis and structural analysis by circular dichroism spectroscopy, which revealed intact structural framework of the fusion construct. Kinetic characterization of the fusion GST-hLDHA protein toward GSH and NADH, suggested retention of functional activities of GST and hLDHA in fused protein as indicated by the kinetic parameters km and kcat/km. Further analysis of effect of temperature and pH on GST-hLDHA activity revealed maximum activity around human physiological conditions (37°C and pH 8). Preservation of the structural and functional characteristics of the fusion enzyme paves the way for potential application for the detection of NADH and GSH in conjunction as biomarkers for cancer diagnosis.
Assuntos
Glutationa Transferase/metabolismo , L-Lactato Desidrogenase/metabolismo , Clonagem Molecular , Glutationa/metabolismo , Glutationa Transferase/genética , Humanos , Concentração de Íons de Hidrogênio , Isoenzimas/genética , Isoenzimas/metabolismo , Cinética , L-Lactato Desidrogenase/genética , Lactato Desidrogenase 5 , NAD/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , TemperaturaRESUMO
OBJECTIVES: To investigate the potential of recombinant phytaspase loaded manganese (Mn) doped zinc sulphide (ZnS) quantum dots embedded chitosan nanoparticles for augmenting cisplatin induced chemotherapy of HeLa cells. RESULTS: The recombinant phytaspase was cloned into bacterial expression vector PGEX-4T-2. The expressed and purified recombinant plant phytaspase protein from Escherichia coli BL21 was immobilized onto the cationic nanocomposite. Confocal microscopy elucidated the delivery of these luminescent nanocomposites inside cervical cancer HeLa cells. A 50% reduction in the viability of HeLa cells was achieved only in the case of phytaspase-nanocomposites-cisplatin combination at a dose of phytaspase (42 nM), nanocomposites (56.3 µg/ml) and cisplatin (0.44 µg/ml). CONCLUSION: Luminescent cationic nanocomposites were developed for intracellular delivery of recombinant phytaspase, which due to its caspase-like activity assisted in substantiating the chemotherapeutic activity of apoptosis inducing drug-cisplatin.
Assuntos
Quitosana/química , Cisplatino/farmacologia , Pontos Quânticos/química , Serina Proteases/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Expressão Gênica , Células HeLa , Humanos , Luminescência , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Nanopartículas , Sulfetos/química , Difração de Raios X , Compostos de Zinco/químicaRESUMO
The Wnt signaling pathway plays a predominant role in aberrant proliferation in myriad of cancers. In non-cancerous cells, Wnts are blocked by the secreted frizzled-related proteins (sFRPs) that are generally downregulated in cancer cells. We have purified and characterized bacterially expressed glutathione S-transferase-tagged SFRP4 from a novel clone generated from human cell origin. Cervical cancer (HeLa) and lung cancer (A549) cells, in which Wnt and associated genes were found to be expressed, were treated with the purified recombinant sFRP4, which revealed a significant dose-dependent cell growth inhibition up to 40 %. The current investigation on functionality of this bacterially produced recombinant sFRP4 in arresting cancer cell proliferation is the first of its kind, where G2/M phase arrest and early apoptosis were evident. Increase in phosphorylated ß-catenin in sFRP4 treatment indicated inhibition of Wnt pathway, which was further confirmed by downregulation of pro-proliferative genes, namely cyclin D1, c-myc, and survivin. Functional activity of recombinant sFRP4 was further exploited in co-therapy module with chemotherapeutic drugs to decipher molecular events. Collectively, our study on purified recombinant sFRP4 from bacterial host holds great promise in targeting Wnt signaling for exploring new strategies to combat cancer.
Assuntos
Antineoplásicos , Divisão Celular/efeitos dos fármacos , Fase G2/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Proteínas Proto-Oncogênicas , Via de Sinalização Wnt/efeitos dos fármacos , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Escherichia coli , Células HEK293 , Células HeLa , Humanos , Proteínas de Neoplasias/biossíntese , Neoplasias/metabolismo , Neoplasias/patologia , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas/farmacologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacologiaRESUMO
BACKGROUND: The Escherichia coli cytosine deaminase (CD)/5-fluorocytosine (5-FC) approach emerges as a potential aid for suicide gene therapy in the field of modern cancer treatment. However, the poor binding affinity of CD towards 5-FC compared to the natural substrate cytosine limits its application for successful suicide gene therapy. Redesigning a bacterial mutant CD with site-directed mutagenesis showed higher potency compare to wild-type CD (wtCD) in vitro. In the present study, we conducted a comparative analysis of F186W mutant and wtCD in a human lung cancer cell line (A549). METHODS AND RESULTS: A comparative investigation was initiated with cell viability analyses by MTT and trypan blue dye exclusion assays on A549 cells transfected with wtCD and F186W genes. The mode of cell death was confirmed by acridine Orange/ethidium Bromide dual staining. Furthermore, flow cytometric assessments were performed by cell cycle analysis and caspase 3 assay. The experimental results showed a drug dependent decrease in cell viability; interestingly, mutant (F186W) reached IC50 at a much lower concentration of prodrug (5-FC) than wtCD. Cell cycle analysis showed that G1 arrest of a larger population of 5-FC treated F186W transfected cells, in contrast to that of wtCD under similar conditions. The caspase 3 assay revealed progression and execution of apoptosis. CONCLUSIONS: We report a novel bacterial CD mutant that provided a superior alternate to the wtCD suicide gene. The F186W mutant required a much lower dose of 5-FC to reach its IC50 , thus minimizing the systemic side effects of large doses of 5-FC as required for wtCD.
Assuntos
Citosina Desaminase/genética , Proteínas de Escherichia coli/genética , Escherichia coli/enzimologia , Terapia Genética , Apoptose/genética , Linhagem Celular Tumoral , Citosina Desaminase/uso terapêutico , Proteínas de Escherichia coli/uso terapêutico , Humanos , Neoplasias Pulmonares/terapia , Mutação , TransgenesRESUMO
Gold nanoclusters in albumin nanoparticles (nanovehicles) are used for single-photon and two-photon imaging of cancer cells following the delivery of doxorubicin through the nanovehicle. NIR excitation and emission wavelengths in the biological window (650-900 nm) make the nanovehicle an ideal potential platform for imaging guided drug delivery.