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1.
J Biomed Sci ; 27(1): 100, 2020 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-33161903

RESUMO

An amendment to this paper has been published and can be accessed via the original article.

2.
Sci Rep ; 9(1): 6529, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31024014

RESUMO

A correction has been published and is appended to both the HTML and PDF versions of this paper. The error has not been fixed in the paper.

3.
BMC Cancer ; 18(1): 749, 2018 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-30025536

RESUMO

After publication of the original article [1], the authors found that Fig. 3 contained an incorrect version of Fig. 3c. This does not affect the Figure legend, results and conclusions of the article.

5.
Drug Discov Today ; 22(11): 1671-1679, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28782687

RESUMO

In elderly aged related macular degeneration (AMD) is the common eye disease which impairs the vision and most of the time it creates permanent vision loss. Because elderly population constitute the larger percentage among society, visual loss due to AMD has become a growing problem. Despite the advances made in developing therapeutics, there is still no satisfactory treatment. The limitations of the available treatments are due to the absence of potent, non-invasive therapy. Furthermore, part of the available drugs targets angiogenesis and create a hypoxic environment that augment further angiogenesis. Therefore, it is reasonable to consider eye integrity and the correlation between hypoxia and angiogenesis before developing successful drugs. This review highlighted issues regarding the available therapeutic strategies and explored whether AMD can be managed by employing specific nanoformulations.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Desenho de Fármacos , Degeneração Macular/tratamento farmacológico , Idoso , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/farmacologia , Animais , Sistemas de Liberação de Medicamentos , Humanos , Degeneração Macular/fisiopatologia , Nanopartículas
6.
Front Plant Sci ; 8: 610, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28533783

RESUMO

Over the years, extensive use of commercially available synthetic pesticides against phytophagous insects has led to their bioaccumulation in the environment causing increased resistance and reduction in soil biodiversity. Further, 90% of the applied pesticides enter the various environmental resources as a result of run-off, exposing the farmers as well as consumers of the agricultural produce to severe health issues. Therefore, growing attention has been given toward the development of alternate environmentally friendly pesticides/insecticides that would aid an efficient pest management system and also prevent chronic exposures leading to diseases. One such strategy is, the use of neem plant's (Binomial name: Azadirachta indica) active ingredients which exhibit agro-medicinal properties conferring insecticidal as well as immunomodulatory and anti-cancer properties. The most prominent constituent of neem is azadirachtin, which has been established as a pivotal insecticidal ingredient. It acts as an antifeedant, repellent, and repugnant agent and induces sterility in insects by preventing oviposition and interrupting sperm production in males. This review discusses, key neem pesticidal components, their active functional ingredients along with recent strategies on employing nanocarriers, to provide controlled release of the active ingredients and to improve their stability and sustainability.

8.
Mini Rev Med Chem ; 17(18): 1688-1695, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-26891936

RESUMO

Increasing evidence suggests that stem cells, a small population of cells with unique selfrenewable and tumour regenerative capacity, are aiding tumour re-growth and multidrug resistance. Conventional therapies are highly ineffective at eliminating these cells leading to relapse of disease and formation of chemoresistance tumours. Cancer and stem cells targeted therapies that utilizes nanotherapeutics to delivery anti-cancer drugs to specific sites are continuously investigated. This review focuses on recent research using nanomedicine and targeting entities to eliminate cancer cells and cancer stem cells. Current nanotherapeutics in clinical trials along with more recent publications on targeted therapies are addressed.


Assuntos
Antineoplásicos/farmacologia , Nanomedicina , Neoplasias/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Antineoplásicos/química , Humanos , Neoplasias/patologia
9.
Drug Discov Today ; 22(1): 111-119, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27693431

RESUMO

Colorectal cancer (CRC) is a major health burden worldwide. The optimal approach to the diagnosis, management, and treatment of CRC involves multidisciplinary and integrated management practices. The field is rapidly changing because of recent advancements in delineating the molecular basis of tumorigenesis, introduction of targeted therapy, varied patient response to mainstay chemotherapeutics, biological drugs, and the effective combination regimes being used for treatment. Recent meta-analysis studies, which tend to establish few clinically useful predictor biomarkers, identify inconsistent results and limitations of the trials. Therefore, molecular pathological epidemiology discipline initiatives are promising. Here, we provide an overview of the potential of biomarker validation for personalized medicine by focusing largely on metastatic (m)CRC. We also highlight new candidate predictive and prognostic biomarkers.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/tratamento farmacológico , Descoberta de Drogas/métodos , Medicina de Precisão/métodos , Animais , Biomarcadores Tumorais/genética , Neoplasias Colorretais/metabolismo , Humanos , Terapia de Alvo Molecular
10.
Sci Rep ; 6: 32062, 2016 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-27576789

RESUMO

Advanced, metastatic, castration resistant and chemo-resistant prostate cancer has triggered change in the drug development landscape against prostate cancer. Bovine lactoferrin (bLf) is currently attracting attention in clinics for its anti-cancer properties and proven safety profile. bLf internalises into cancer cells via receptor mediated endocytosis, boosts immunity and complements chemotherapy. We employed bLf as an excellent functional carrier protein for delivering doxorubicin (Dox) into DU145 cells, CD44+/EpCAM+ double positive enriched DU145 3D prostaspheres and drug resistant ADR1000-DU145 cells, thus circumventing Dox efflux, to overcome chemo-resistance. Successful bLf-Dox conjugation with iron free or iron saturated bLf forms did not affect the integrity and functionality of bLf and Dox. bLf-Dox internalised into DU145 cells within 6 h, enhanced nuclear Dox retention up to 24 h, and proved significantly effective (p < 0.001) in reducing LC50 value of Dox from 5.3 µM to 1.3 µM (4 fold). Orally fed iron saturated bLf-Dox inhibited tumour development, prolonged survival, reduced Dox induced general toxicity, cardiotoxicity, neurotoxicity in TRAMP mice and upregulated serum levels of anti-cancer molecules TNF-α, IFN-γ, CCL4 and CCL17. The study identifies promising potential of a novel and safer bLf-Dox conjugate containing a conventional cytotoxic drug along with bLf protein to target drug resistance.


Assuntos
Adenocarcinoma/tratamento farmacológico , Doxorrubicina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Lactoferrina/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Inibidores da Topoisomerase II/uso terapêutico , Adenocarcinoma/patologia , Animais , Apoptose/efeitos dos fármacos , Bovinos , Linhagem Celular Tumoral , Quimiocina CCL17/sangue , Quimiocina CCL4/sangue , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Portadores de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Interferon gama/sangue , Ferro/farmacocinética , Lactoferrina/administração & dosagem , Lactoferrina/farmacocinética , Masculino , Camundongos , Camundongos Transgênicos , Proteínas de Neoplasias/sangue , Neoplasias da Próstata/patologia , Esferoides Celulares/efeitos dos fármacos , Inibidores da Topoisomerase II/administração & dosagem , Inibidores da Topoisomerase II/farmacocinética , Fator de Necrose Tumoral alfa/análise
11.
Mol Ther Nucleic Acids ; 5(8): e358, 2016 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-27574784

RESUMO

Retinoblastoma (RB) is an intraocular childhood tumor which, if left untreated, leads to blindness and mortality. Nucleolin (NCL) protein which is differentially expressed on the tumor cell surface, binds ligands and regulates carcinogenesis and angiogenesis. We found that NCL is over expressed in RB tumor tissues and cell lines compared to normal retina. We studied the effect of nucleolin-aptamer (NCL-APT) to reduce proliferation in RB tumor cells. Aptamer treatment on the RB cell lines (Y79 and WERI-Rb1) led to significant inhibition of cell proliferation. Locked nucleic acid (LNA) modified NCL-APT administered subcutaneously (s.c.) near tumor or intraperitoneally (i.p.) in Y79 xenografted nude mice resulted in 26 and 65% of tumor growth inhibition, respectively. Downregulation of inhibitor of apoptosis proteins, tumor miRNA-18a, altered serum cytokines, and serum miRNA-18a levels were observed upon NCL-APT treatment. Desorption electrospray ionization mass spectrometry (DESI MS)-based imaging of cell lines and tumor tissues revealed changes in phosphatidylcholines levels upon treatment. Thus, our study provides proof of concept illustrating NCL-APT-based targeted therapeutic strategy and use of DESI MS-based lipid imaging in monitoring therapeutic responses in RB.

12.
Int J Mol Sci ; 17(6)2016 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-27294920

RESUMO

Clipping of recombinant proteins is a major issue in animal cell cultures. A recombinant Fc-fusion protein, VEGFR1(D1-D3)-Fc expressed in CHOK1SV GS-KO cells was observed to be undergoing clippings in lab scale cultures. Partial cleaving of expressed protein initiated early on in cell culture and was observed to increase over time in culture and also on storage. In this study, a few parameters were explored in a bid to inhibit clipping in the fusion protein The effects of culture temperature, duration of culture, the addition of an anti-clumping agent, ferric citrate and use of protease inhibitor cocktail on inhibition of proteolysis of the Fc fusion were studied. Lowering of culture temperature from 37 to 30 °C alone appears to be the best solution for reducing protein degradation from the quality, cost and regulatory points of view. The obtained Fc protein was characterized and found to be in its stable folded state, exhibiting a high affinity for its ligand and also biological and functional activities.


Assuntos
Fragmentos Fc das Imunoglobulinas/metabolismo , Processamento de Proteína Pós-Traducional , Proteínas Recombinantes de Fusão/metabolismo , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Células CHO , Cricetinae , Cricetulus , Células HEK293 , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Proteólise , Proteínas Recombinantes de Fusão/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética
13.
J Pediatr Hematol Oncol ; 38(7): e230-42, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27322712

RESUMO

Apoptosis is a natural process regulated by apoptotic and antiapoptotic molecules. We investigated mRNA expression of survivin and its splice variants, along with B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax), in a cohort of 20 retinoblastoma (RB) tumors by real-time polymerase chain reaction. We hypothesized a correlation between the Bcl-2/Bax and survivin splice variants and also that expression of these would be associated with clinicopathologic features of tumors. The Bcl-2 expression was significantly higher (P<0.001) in RB, and Bcl-2/Bax ratio was remarkably higher in poorly differentiated tumors. A statistically significant higher expression of Survivin-WT (wild type) compared with its variant Survivin-2ß (P<0.05) was observed. Bcl-2 did not exhibit positive correlation with any of the survivin variants except Survivin-2ß, whereas Bax exhibited significant (P<0.05) correlation with the variants. Thus, it could be suggested that a superior player out of a likely interaction between the variants and Bcl-2/Bax uses its activity for the progression of RB. Silencing of Survivin-WT in the Y79 cell line was studied by siRNA technology and cell-permeable dominant negative survivin (SurR9-C84A). siRNA showed higher proapoptotic effects and increased caspase 3/7 activity in Y79 cells. Effective internalization of SurR9-C84A in Y79 cells induced cytotoxic effects. Thus, the current study confirms survivin as a promising target for therapy.


Assuntos
Proteínas Inibidoras de Apoptose/genética , Proteínas Proto-Oncogênicas c-bcl-2/genética , Neoplasias da Retina/patologia , Retinoblastoma/patologia , Proteína X Associada a bcl-2/genética , Apoptose , Linhagem Celular Tumoral , Sobrevivência Celular , Feminino , Humanos , Lactente , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Masculino , RNA Mensageiro/análise , RNA Interferente Pequeno/genética , Neoplasias da Retina/metabolismo , Neoplasias da Retina/terapia , Retinoblastoma/metabolismo , Retinoblastoma/terapia , Survivina
14.
Int J Nanomedicine ; 11: 1349-66, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27099495

RESUMO

The present study successfully developed orally deliverable multimodular zinc (Zn) iron oxide (Fe3O4)-saturated bovine lactoferrin (bLf)-loaded polymeric nanocapsules (NCs), and evaluated their theranostic potential (antitumor efficacy, magnetophotothermal efficacy and imaging capability) in an in vivo human xenograft CpG-island methylator phenotype (CIMP)-1(+)/CIMP2(-)/chromosome instability-positive colonic adenocarcinoma (Caco2) and claudin-low, triple-negative (ER(-)/PR(-)/HER2(-); MDA-MB-231) breast cancer model. Mice fed orally on the Zn-Fe-bLf NC diet showed downregulation in tumor volume and complete regression in tumor volume after 45 days of feeding. In human xenograft colon cancer, vehicle-control NC diet-group (n=5) mice showed a tumor volume of 52.28±11.55 mm(3), and Zn-Fe-bLf NC diet (n=5)-treated mice had a tumor-volume of 0.10±0.073 mm(3). In the human xenograft breast cancer model, Zn-Fe-bLf NC diet (n=5)-treated mice showed a tumor volume of 0.051±0.062 mm(3) within 40 days of feeding. Live mouse imaging conducted by near-infrared fluorescence imaging of Zn-Fe-bLf NCs showed tumor site-specific localization and regression of colon and breast tumor volume. Ex vivo fluorescence-imaging analysis of the vital organs of mice exhibited sparse localization patterns of Zn-Fe-bLf NCs and also confirmed tumor-specific selective localization patterns of Zn-Fe-bLf NCs. Dual imaging using magnetic resonance imaging and computerized tomography scans revealed an unprecedented theranostic ability of the Zn-Fe-bLf NCs. These observations warrant consideration of multimodular Zn-Fe-bLf NCs for real-time cancer imaging and simultaneous cancer-targeted therapy.


Assuntos
Proteínas de Transporte/metabolismo , Neoplasias do Colo/tratamento farmacológico , Lactoferrina/química , Nanocápsulas/administração & dosagem , Nanomedicina Teranóstica , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Zinco/química , Adenocarcinoma/tratamento farmacológico , Animais , Bovinos , Feminino , Compostos Férricos/química , Humanos , Camundongos , Camundongos Nus , Nanocápsulas/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Artigo em Inglês | MEDLINE | ID: mdl-26924735

RESUMO

BACKGROUND: Survivin is widely overexpressed in many forms of cancer and studies have related high survivin expression with poor survival rates. Although, there have been several attempts to target survivin, most therapeutics haven't shown substantial success in clinical trials therefore, authors wish to attract the focus towards many recent therapeutic innovations to target survivin. OBJECTIVE: Survivin plays an essential role in the cell cycle progression, apoptosis, cell stress response, drug resistance and angiogenesis therefore the prognostic and targeting benefits of survivin have been underestimated. An update on the current and existing therapeutic strategies implemented to target survivin is provided. Therefore, the reader will gain an insight into the recent patents targeting survivin. The review has emphasised on patents for quantification of survivin, survivin peptides as immunotherapeutics, application of survivin promoters, RNA interference of survivin, small molecules inhibitors of survivin and nanoparticles targeting survivin. The review also encompasses the survivin targeted therapeutics being implemented at clinical stages which include survivin targeted immunotherapeutics, peptide-based vaccines, antisense oligonucleotides and chemical inhibitors. CONCLUSION: We reviewed recent patents based on preclinical anti-survivin therapies reported to date and it was concluded that gataparsen has been most widely used for anti-survivin therapy in clinical trials. It was also concluded that most therapeutic patents were focussed on development of natural anti-survivin therapeutics such as anti-survivin peptides or survivin anti-sense oligonucleotides in the recent years therefore, proving that natural proteins and nucleic acids has an upper hand over chemicals and synthetic drugs.


Assuntos
Antineoplásicos/farmacologia , Proteínas Inibidoras de Apoptose/antagonistas & inibidores , Proteínas Inibidoras de Apoptose/fisiologia , Patentes como Assunto , Sequência de Aminoácidos , Animais , Antineoplásicos/uso terapêutico , Docetaxel , Humanos , Proteínas Inibidoras de Apoptose/genética , Proteínas Inibidoras de Apoptose/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Estrutura Secundária de Proteína , Survivina , Taxoides/farmacologia , Taxoides/uso terapêutico
16.
Nanomedicine (Lond) ; 11(3): 249-68, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26785603

RESUMO

AIM: To unravel the multimodal nanotheranostic ability of Fe3O4-saturated bovine lactoferrin nanocapsules (FebLf NCs) in claudin-low, triple-negative breast cancer model. MATERIALS & METHODS: Xenograft study was performed to examine biocompatibility, antitumor efficacy and multimodal nanotheranostic action in combination with near-infrared live mice imaging. RESULTS: FebLf NCs exhibited a size range of 80 nm ± 5 nm with observed superparamagnetism. FebLf NCs successfully internalized into breast cancer cells through receptor-mediated endocytosis and induced apoptosis through the downregulation of inhibitor of apoptosis survivin and livin proteins. Investigations revealed a remarkable biocompatibility, anticancer efficacy of the FebLf NCs. Near-infrared imaging observations confirmed selective localization of multimodal FebLf NCs at the tumor site and lead to time-dependent reduction of tumor growth. CONCLUSION: FebLf NCs can be safe, biocompatible nanotheranostic approach for real-time imaging and monitoring the effect of drugs in real time and have potentials in future clinical trials.


Assuntos
Compostos Férricos/metabolismo , Lactoferrina/metabolismo , Nanocápsulas , Nanomedicina Teranóstica , Neoplasias de Mama Triplo Negativas/terapia , Claudinas/metabolismo , Feminino , Humanos
17.
Int J Nanomedicine ; 11: 25-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26730188

RESUMO

This study used the Eri silk nanoparticles (NPs) for delivering apo-bovine lactoferrin (Apo-bLf) (~2% iron saturated) and Fe-bLf (100% iron saturated) in MDA-MB-231 and MCF-7 breast cancer cell lines. Apo-bLf and Fe-bLf-loaded Eri silk NPs with sizes between 200 and 300 nm (±10 nm) showed a significant internalization within 4 hours in MDA-MB-231 cells when compared to MCF-7 cells. The ex vivo loop assay with chitosan-coated Fe-bLf-loaded silk NPs was able to substantiate its future use in oral administration and showed the maximum absorption within 24 hours by ileum. Both Apo-bLf and Fe-bLf induced increase in expression of low-density lipoprotein receptor-related protein 1 and lactoferrin receptor in epidermal growth factor (EGFR)-positive MDA-MB-231 cells, while transferrin receptor (TfR) and TfR2 in MCF-7 cells facilitated the receptor-mediated endocytosis of NPs. Controlled and sustained release of both bLf from silk NPs was shown to induce more cancer-specific cytotoxicity in MDA-MB-231 and MCF-7 cells compared to normal MCF-10A cells. Due to higher degree of internalization, the extent of cytotoxicity and apoptosis was significantly higher in MDA-MB-231 (EGFR+) cells when compared to MCF-7 (EGFR-) cells. The expression of a prominent anticancer target, survivin, was found to be downregulated at both gene and protein levels. Taken together, all the observations suggest the potential use of Eri silk NPs as a delivery vehicle for an anti-cancer milk protein, and indicate bLf for the treatment of breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Sistemas de Liberação de Medicamentos/métodos , Lactoferrina/farmacologia , Nanopartículas/administração & dosagem , Seda/química , Animais , Apoproteínas/administração & dosagem , Apoproteínas/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Bovinos , Quitosana/química , Quitosana/metabolismo , Sistemas de Liberação de Medicamentos/instrumentação , Feminino , Humanos , Ferro/química , Lactoferrina/administração & dosagem , Células MCF-7/efeitos dos fármacos , Camundongos , Mariposas/química , Nanopartículas/química , Nanopartículas/metabolismo , Receptores de Superfície Celular/metabolismo
18.
J Biomed Nanotechnol ; 12(9): 1758-73, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29345887

RESUMO

Efficient early detection of cancer and its simultaneous therapy can improve the survival of cancer patients significantly. Recently there is great interest for the development of nanotheranostic systems with multimodal live real-time imaging ability. Novel multimodal multifunctional iron oxide (Fe3O4) saturated lactoferrin (FebLf) nanocapsules/nanocarriers (FebLf NCs) nanoformulation was fabricated. Anti-cancer nanotheranostic ability in human xenograft colonic adenocarcinoma model was conducted in vivo by employing near infrared flouroscence (NIRF) real time live mice imaging technology. FebLf NCs showed spherical morphology with 50 to 80 nm size with super paramagnetic property and exhibited profound in vivo anti-tumour efficacy, leading to regression of the xenograft colonic tumour growth over a 90 day trial period. NIRF real time imaging revealed selective localisation patterns of the FebLf NCs at the tumour site causing tumour growth inhibition. In turn, ex vivo NIRF imaging of mice organs showed enhanced tumoural uptake and biodistribution at the vital organs including spleen, intestine, kidney, and intestine. Low-density lipoprotein receptors (LDLRs), ferroportin, ferritin receptor based in vivo internalisation mechanisms and iron metabolism regulation were observed. Histopathological analysis revealed obsolute non-toxic nature of FebLf NCs in mice tissues. These observations summate biocompatible, multimodal anticancer activity of novel FebLf NCs for real time cancer therapeutic imaging leading to targeted colonic adenocarcinoma therapy.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Lactoferrina , Nanopartículas de Magnetita/química , Nanocápsulas/química , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/diagnóstico por imagem , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Humanos , Lactoferrina/química , Lactoferrina/farmacocinética , Camundongos , Espectroscopia de Luz Próxima ao Infravermelho , Nanomedicina Teranóstica , Distribuição Tecidual , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Biomicrofluidics ; 9(5): 054110, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26487896

RESUMO

The role of circulating tumor cells (CTCs) in disease diagnosis, prognosis, monitoring of the therapeutic efficacy, and clinical decision making is immense and has attracted tremendous focus in the last decade. We designed and fabricated simple, flat channel microfluidic devices polydimethylsiloxane (PDMS based) functionalized with locked nucleic acid (LNA) modified aptamers (targeting epithelial cell adhesion molecule (EpCAM) and nucleolin expression) for quick and efficient capture of CTCs and cancer cells. With optimized flow rates (10 µl/min), it was revealed that the aptamer modified devices offered reusability for up to six times while retaining optimal capture efficiency (>90%) and specificity. High capture sensitivity (92%) and specificity (100%) was observed in whole blood samples spiked with Caco-2 cells (10-100 cells/ml). Analysis of blood samples obtained from 25 head and neck cancer patients on the EpCAM LNA aptamer functionalized chip revealed that an average count of 5 ± 3 CTCs/ml of blood were captured from 22/25 samples (88%). EpCAM intracellular domain (EpICD) immunohistochemistry on 9 oral squamous cell carcinomas showed the EpICD positivity in the tumor cells, confirming the EpCAM expression in CTCs from head and neck cancers. These microfluidic devices also maintained viability for in vitro culture and characterization. Use of LNA modified aptamers provided added benefits in terms of cost effectiveness due to increased reusability and sustainability of the devices. Our results present a robust, quick, and efficient CTC capture platform with the use of simple PDMS based devices that are easy to fabricate at low cost and have an immense potential in cancer diagnosis, prognosis, and therapeutic planning.

20.
Nucleic Acid Ther ; 25(6): 317-22, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26334953

RESUMO

Aptamers are chimerized with drug or antisense oligos or nanoparticles to generate targeted therapeutics for cancer. Aptamer chimerized siRNA rescues nonspecific delivery and, thereby, enhances the availability of siRNA to target cells. EpCAM RNA aptamer (EpApt or Ep) has potential for siRNA chimerization due to its secondary structure. Stathmin and survivin proteins are reported to aid oncogenicity in retinoblastoma (RB), breast cancer and other cancers. Thus, chimerization of EpCAM Apt with siRNA against survivin and stathmin, respectively, was performed by incorporating Locked Nucleic Acid (LNA) modification. The LNA-modified chimeric aptamers were stable until 96 h and got internalized into RB, WERI-Rb1 and breast cancer, MDAMB453 cell lines. The constructs were studied using the recombinant dicer enzyme for the siRNA generation. Quantitative polymerase chain reaction and immunofluorescence by microscopic analysis of chimeras in vitro exhibited silencing of stathmin and survivin in the RB and breast cancer model. The chimeric constructs showed significant inhibition of cell proliferation of breast cancer cells. Thus, LNA-modified aptamer-based siRNA delivery aids in cell targeting and necessitates further studies in animal models.


Assuntos
Aptâmeros de Nucleotídeos/uso terapêutico , Neoplasias/patologia , Oligonucleotídeos/genética , RNA Interferente Pequeno/genética , Antígenos de Neoplasias/genética , Aptâmeros de Nucleotídeos/genética , Moléculas de Adesão Celular/genética , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Inativação Gênica , Humanos
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