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1.
J Am Chem Soc ; 143(25): 9297-9302, 2021 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-34137598

RESUMEN

Inhibitors of transcriptional protein-protein interactions (PPIs) have high value both as tools and for therapeutic applications. The PPI network mediated by the transcriptional coactivator Med25, for example, regulates stress-response and motility pathways, and dysregulation of the PPI networks contributes to oncogenesis and metastasis. The canonical transcription factor binding sites within Med25 are large (∼900 Å2) and have little topology, and thus, they do not present an array of attractive small-molecule binding sites for inhibitor discovery. Here we demonstrate that the depsidone natural product norstictic acid functions through an alternative binding site to block Med25-transcriptional activator PPIs in vitro and in cell culture. Norstictic acid targets a binding site comprising a highly dynamic loop flanking one canonical binding surface, and in doing so, it both orthosterically and allosterically alters Med25-driven transcription in a patient-derived model of triple-negative breast cancer. These results highlight the potential of Med25 as a therapeutic target as well as the inhibitor discovery opportunities presented by structurally dynamic loops within otherwise challenging proteins.


Asunto(s)
Lactonas/farmacología , Complejo Mediador/metabolismo , Unión Proteica/efectos de los fármacos , Salicilatos/farmacología , Transcripción Genética/efectos de los fármacos , Regulación Alostérica , Línea Celular Tumoral , Proteínas de Unión al ADN/metabolismo , Humanos , Complejo Mediador/química , Simulación de Dinámica Molecular , Dominios Proteicos , Factores de Transcripción/metabolismo
2.
J Cell Sci ; 131(8)2018 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-29588397

RESUMEN

Defective endocytosis and vesicular trafficking of signaling receptors has recently emerged as a multifaceted hallmark of malignant cells. Clathrin-coated pits (CCPs) display highly heterogeneous dynamics on the plasma membrane where they can take from 20 s to over 1 min to form cytosolic coated vesicles. Despite the large number of cargo molecules that traffic through CCPs, it is not well understood whether signaling receptors activated in cancer, such as epidermal growth factor receptor (EGFR), are regulated through a specific subset of CCPs. The signaling lipid phosphatidylinositol (3,4,5)-trisphosphate [PI(3,4,5)P3], which is dephosphorylated by phosphatase and tensin homolog (PTEN), is a potent tumorigenic signaling lipid. By using total internal reflection fluorescence microscopy and automated tracking and detection of CCPs, we found that EGF-bound EGFR and PTEN are enriched in a distinct subset of short-lived CCPs that correspond with clathrin-dependent EGF-induced signaling. We demonstrated that PTEN plays a role in the regulation of CCP dynamics. Furthermore, increased PI(3,4,5)P3 resulted in higher proportion of short-lived CCPs, an effect that recapitulates PTEN deletion. Altogether, our findings provide evidence for the existence of short-lived 'signaling-capable' CCPs.


Asunto(s)
Invaginaciones Cubiertas de la Membrana Celular/metabolismo , Receptores ErbB/metabolismo , Fosfohidrolasa PTEN/genética , Humanos , Transducción de Señal
3.
Breast Cancer Res Treat ; 179(2): 337-347, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31655920

RESUMEN

PURPOSE: There is a need for biomarkers of drug efficacy for targeted therapies in triple-negative breast cancer (TNBC). As a step toward this, we identify multi-omic molecular determinants of anti-TNBC efficacy in cell lines for a panel of oncology drugs. METHODS: Using 23 TNBC cell lines, drug sensitivity scores (DSS3) were determined using a panel of investigational drugs and drugs approved for other indications. Molecular readouts were generated for each cell line using RNA sequencing, RNA targeted panels, DNA sequencing, and functional proteomics. DSS3 values were correlated with molecular readouts using a FDR-corrected significance cutoff of p* < 0.05 and yielded molecular determinant panels that predict anti-TNBC efficacy. RESULTS: Six molecular determinant panels were obtained from 12 drugs we prioritized based on their efficacy. Determinant panels were largely devoid of DNA mutations of the targeted pathway. Molecular determinants were obtained by correlating DSS3 with molecular readouts. We found that co-inhibiting molecular correlate pathways leads to robust synergy across many cell lines. CONCLUSIONS: These findings demonstrate an integrated method to identify biomarkers of drug efficacy in TNBC where DNA predictions correlate poorly with drug response. Our work outlines a framework for the identification of novel molecular determinants and optimal companion drugs for combination therapy based on these correlates.


Asunto(s)
Antineoplásicos/farmacología , Resistencia a Antineoplásicos , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/etiología , Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Línea Celular Tumoral , Biología Computacional/métodos , Relación Dosis-Respuesta a Droga , Resistencia a Antineoplásicos/genética , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Perfilación de la Expresión Génica , Humanos , Mutación , Proteómica , Resultado del Tratamiento , Neoplasias de la Mama Triple Negativas/metabolismo
4.
Small ; 15(5): e1802891, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30632269

RESUMEN

Cancer stem-like cells (CSCs) have been shown to initiate tumorigenesis and cancer metastasis in many cancer types. Although identification of CSCs through specific marker expression helps define the CSC compartment, it does not directly provide information on how or why this cancer cell subpopulation is more metastatic or tumorigenic. In this study, the functional and biophysical characteristics of aggressive and lethal inflammatory breast cancer (IBC) CSCs at the single-cell level are comprehensively profiled using multiple microengineered tools. Distinct functional (cell migration, growth, adhesion, invasion and self-renewal) and biophysical (cell deformability, adhesion strength and contractility) properties of ALDH+ SUM149 IBC CSCs are found as compared to their ALDH- non-CSC counterpart, providing biophysical insights into why CSCs has an enhanced propensity to metastasize. It is further shown that the cellular biophysical phenotype can predict and determine IBC cells' tumorigenic ability. SUM149 and SUM159 IBC cells selected and modulated through biophysical attributes-adhesion and stiffness-show characteristics of CSCs in vitro and enhance tumorigenicity in in vivo murine models of primary tumor growth. Overall, the multiparametric cellular biophysical phenotyping and modulation of IBC CSCs yields a new understanding of IBC's metastatic properties and how they might develop and be targeted for therapeutic interventions.


Asunto(s)
Aldehído Deshidrogenasa/metabolismo , Biofisica , Neoplasias Inflamatorias de la Mama/enzimología , Neoplasias Inflamatorias de la Mama/patología , Células Madre Neoplásicas/enzimología , Células Madre Neoplásicas/patología , Fenómenos Biomecánicos , Carcinogénesis/metabolismo , Carcinogénesis/patología , Adhesión Celular , Línea Celular Tumoral , Femenino , Humanos , Fenotipo
5.
J Biol Chem ; 291(26): 13715-29, 2016 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-27129239

RESUMEN

Inflammatory breast cancer (IBC) is an extremely lethal cancer that rapidly metastasizes. Although the molecular attributes of IBC have been described, little is known about the underlying metabolic features of the disease. Using a variety of metabolic assays, including (13)C tracer experiments, we found that SUM149 cells, the primary in vitro model of IBC, exhibit metabolic abnormalities that distinguish them from other breast cancer cells, including elevated levels of N-acetylaspartate, a metabolite primarily associated with neuronal disorders and gliomas. Here we provide the first evidence of N-acetylaspartate in breast cancer. We also report that the oncogene RhoC, a driver of metastatic potential, modulates glutamine and N-acetylaspartate metabolism in IBC cells in vitro, revealing a novel role for RhoC as a regulator of tumor cell metabolism that extends beyond its well known role in cytoskeletal rearrangement.


Asunto(s)
Ácido Aspártico/análogos & derivados , Glutamina/metabolismo , Neoplasias Inflamatorias de la Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas de Unión al GTP rho/metabolismo , Ácido Aspártico/biosíntesis , Ácido Aspártico/genética , Línea Celular Tumoral , Femenino , Glutamina/genética , Humanos , Neoplasias Inflamatorias de la Mama/genética , Neoplasias Inflamatorias de la Mama/patología , Proteínas de Neoplasias/genética , Proteínas de Unión al GTP rho/genética , Proteína rhoC de Unión a GTP
6.
J Nanosci Nanotechnol ; 17(1): 833-36, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-29634179

RESUMEN

The CeO2 nanoboxes with well-defined hollow structure were fabricated by template-engaged coordinating etching of Cu2O cubes based on Pearson's hard and soft acid-base principle. The morphologically uniform CeO2 nanoboxes have an average edge length of 400 nm and shell thickness of around 60 nm. The strong chemical affinity between Cu+ and S2O(2− 3) was the driving force for the etching of Cu2O templates and the formation of shells. A possible formation mechanism of CeO2 nanoboxes was proposed. The synthesized CeO2 nanoboxes exhibit good photocatalytic activity for photodegradation of acid orange 7 (AO 7) under visible light irradiation.

7.
BMC Cancer ; 16: 614, 2016 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-27501846

RESUMEN

BACKGROUND: Circulating tumor cells (CTCs) have shown prognostic relevance in many cancer types. However, the majority of current CTC capture methods rely on positive selection techniques that require a priori knowledge about the surface protein expression of disseminated CTCs, which are known to be a dynamic population. METHODS: We developed a microfluidic CTC capture chip that incorporated a nanoroughened glass substrate for capturing CTCs from blood samples. Our CTC capture chip utilized the differential adhesion preference of cancer cells to nanoroughened etched glass surfaces as compared to normal blood cells and thus did not depend on the physical size or surface protein expression of CTCs. RESULTS: The microfluidic CTC capture chip was able to achieve a superior capture yield for both epithelial cell adhesion molecule positive (EpCAM+) and EpCAM- cancer cells in blood samples. Additionally, the microfluidic CTC chip captured CTCs undergoing transforming growth factor beta-induced epithelial-to-mesenchymal transition (TGF-ß-induced EMT) with dynamically down-regulated EpCAM expression. In a mouse model of human breast cancer using EpCAM positive and negative cell lines, the number of CTCs captured correlated positively with the size of the primary tumor and was independent of their EpCAM expression. Furthermore, in a syngeneic mouse model of lung cancer using cell lines with differential metastasis capability, CTCs were captured from all mice with detectable primary tumors independent of the cell lines' metastatic ability. CONCLUSIONS: The microfluidic CTC capture chip using a novel nanoroughened glass substrate is broadly applicable to capturing heterogeneous CTC populations of clinical interest independent of their surface marker expression and metastatic propensity. We were able to capture CTCs from a non-metastatic lung cancer model, demonstrating the potential of the chip to collect the entirety of CTC populations including subgroups of distinct biological and phenotypical properties. Further exploration of the biological potential of metastatic and presumably non-metastatic CTCs captured using the microfluidic chip will yield insights into their relevant differences and their effects on tumor progression and cancer outcomes.


Asunto(s)
Separación Celular/métodos , Molécula de Adhesión Celular Epitelial/metabolismo , Técnicas Analíticas Microfluídicas/métodos , Neoplasias/metabolismo , Células Neoplásicas Circulantes/patología , Factor de Crecimiento Transformador beta/farmacología , Células A549 , Animales , Adhesión Celular , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/efectos de los fármacos , Femenino , Heterogeneidad Genética , Humanos , Células MCF-7 , Ratones , Metástasis de la Neoplasia , Trasplante de Neoplasias , Neoplasias/patología , Células Neoplásicas Circulantes/efectos de los fármacos , Células Neoplásicas Circulantes/metabolismo
8.
J Nanosci Nanotechnol ; 16(5): 4929-35, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27483848

RESUMEN

Zinc oxide (ZnO) hollow rods were fabricated by precipitation method with Bacillus subtilis as template. CdS nanoparticles were then decorated on the surface of the ZnO rods through hydrothermal method. The as-prepared samples were characterized using X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscope and ultraviolet-visible spectroscopy techniques. The ZnO/CdS composite hollow rods copied the morphology of Bacillus subtiis. A possible formation mechanism of the rods was proposed. The photocatalytic activity of the samples was further evaluated through the photodegradation of Rhodamine B under a simulated solar-light irradiation. Results indicated that the photocatalytic activity of the rods improved greatly.


Asunto(s)
Bacillus subtilis/ultraestructura , Compuestos de Cadmio/química , Nanotubos/química , Nanotubos/ultraestructura , Rodaminas/química , Compuestos de Selenio/química , Óxido de Zinc/química , Bacillus subtilis/química , Catálisis/efectos de la radiación , Ensayo de Materiales , Impresión Molecular/métodos , Nanotubos/efectos de la radiación , Fotoquímica/métodos , Dosis de Radiación , Rodaminas/efectos de la radiación , Energía Solar , Óxido de Zinc/efectos de la radiación
9.
Foods ; 13(20)2024 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-39456393

RESUMEN

To achieve the rapid grade classification of camellia seed oil, hyperspectral imaging technology was used to acquire hyperspectral images of three distinct grades of camellia seed oil. The spectral and image information collected by the hyperspectral imaging technology was preprocessed by different methods. The characteristic wavelength selection in this study included the continuous projections algorithm (SPA) and competitive adaptive reweighted sampling (CARS), and the gray-level co-occurrence matrix (GLCM) algorithm was used to extract the texture features of camellia seed oil at the characteristic wavelength. Combined with genetic algorithm (GA) and support vector machine algorithm (SVM), different grade classification models for camellia seed oil were developed using full wavelengths (GA-SVM), characteristic wavelengths (CARS-GA-SVM), and fusing spectral and image features (CARS-GLCM-GA-SVM). The results show that the CARS-GLCM-GA-SVM model, which combined spectral and image information, had the best classification effect, and the accuracy of the calibration set and prediction set of the CARS-GLCM-GA-SVM model were 98.30% and 96.61%, respectively. Compared with the CARS-GA-SVM model, the accuracy of the calibration set and prediction set were improved by 10.75% and 12.04%, respectively. Compared with the GA-SVM model, the accuracy of the calibration set and prediction set were improved by 18.28% and 18.15%, respectively. The research showed that hyperspectral imaging technology can rapidly classify camellia seed oil grades.

10.
NPJ Breast Cancer ; 10(1): 43, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858374

RESUMEN

Fatty acid synthesis (FAS) has been shown to play a key role in the survival of brain-metastatic (BM) breast cancer. We demonstrate that the fatty acid synthase inhibitor TVB-2640 synergizes with the topoisomerase inhibitor SN-38 in triple-negative breast cancer (TNBC) BM cell lines, upregulates FAS and downregulates cell cycle progression gene expression, and slows the motility of TNBC BM cell lines. The combination of SN-38 and TVB-2640 warrants further consideration as a potential therapeutic option in TNBC BMs.

11.
Eur Urol ; 2024 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-39155193

RESUMEN

BACKGROUND AND OBJECTIVE: Predicting response to therapy for each patient's tumor is critical to improving long-term outcomes for muscle-invasive bladder cancer. This study aims to establish ex vivo bladder cancer patient-derived organoid (PDO) models that are representative of patients' tumors and determine the potential efficacy of standard of care and curated experimental therapies. METHODS: Tumor material was collected prospectively from consented bladder cancer patients to generate short-term PDO models, which were screened against a panel of clinically relevant drugs in ex vivo three-dimensional culture. Multiomic profiling was utilized to validate the PDO models, establish the molecular characteristics of each tumor, and identify potential biomarkers of drug response. Gene expression (GEX) patterns between paired primary tissue and PDO samples were assessed using Spearman's rank correlation coefficients. Molecular correlates of therapy response were identified using Pearson correlation coefficients and Kruskal-Wallis tests with Dunn's post hoc pairwise comparison testing. KEY FINDINGS AND LIMITATIONS: A total of 106 tumors were collected from 97 patients, with 65 samples yielding sufficient material for complete multiomic molecular characterization and PDO screening with six to 32 drugs/combinations. Short-term PDOs faithfully represent the tumor molecular characteristics, maintain diverse cell types, and avoid shifts in GEX-based subtyping that accompany long-term PDO cultures. Utilizing an integrative approach, novel correlations between ex vivo drug responses and genomic alterations, GEX, and protein expression were identified, including a multiomic signature of gemcitabine response. The positive predictive value of ex vivo drug responses and the novel multiomic gemcitabine response signature need to be validated in future studies. CONCLUSIONS AND CLINICAL IMPLICATIONS: Short-term PDO cultures retain the molecular characteristics of tumor tissue and avoid shifts in expression-based subtyping that have plagued long-term cultures. Integration of multiomic profiling and ex vivo drug screening data identifies potential predictive biomarkers, including a novel signature of gemcitabine response. PATIENT SUMMARY: Better models are needed to predict patient response to therapy in bladder cancer. We developed a platform that uses short-term culture to best mimic each patient's tumor and assess potential sensitivity to therapeutics.

12.
Adv Nanobiomed Res ; 3(4)2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37234365

RESUMEN

Brain metastases are the most lethal progression event, in part because the biological processes underpinning brain metastases are poorly understood. There is a paucity of realistic models of metastasis, as current in vivo murine models are slow to manifest metastasis. We set out to delineate metabolic and secretory modulators of brain metastases by utilizing two models consisting of in vitro microfluidic devices: 1) a blood brain niche (BBN) chip that recapitulates the blood-brain-barrier and niche; and 2) a migration chip that assesses cell migration. We report secretory cues provided by the brain niche that attract metastatic cancer cells to colonize the brain niche region. Astrocytic Dkk-1 is increased in response to brain-seeking breast cancer cells and stimulates cancer cell migration. Brain-metastatic cancer cells under Dkk-1 stimulation increase gene expression of FGF-13 and PLCB1. Further, extracellular Dkk-1 modulates cancer cell migration upon entering the brain niche.

13.
ChemSusChem ; 15(13): e202200392, 2022 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-35373919

RESUMEN

5-Hydroxymethylfurfural (HMF) containing C=O, C-O, and furan ring functional groups is an important platform chemical derived from C6 sugars. The selective hydrogenation of C=O in HMF produces 2,5-dihydroxymethylfuran (DHMF), which is a potential sustainable substitute for petroleum-based building blocks. Here, 2,5-furandicarboxylic acid (H2 FDC), a promising sustainable alternative to terephthalic acid, was employed as a renewable ligand to synthesize a novel Cu metal-organic framework (Cu-FDC). With a polyvinyl pyrrolidone (PVP)-assisted approach, 2D Cu-FDC nano-lamellae of micrometer lateral dimensions and nanometer thickness could be obtained, which could be used as a precursor to fabricate 2D oxygen-rich carbon nanosheets embedded with Cu nanoparticles (denoted CFP-300) after a thermal treatment at 300 °C under N2 atmosphere. The synthesized CFP-300 exhibited excellent catalytic performance and stability for the selective hydrogenation of HMF to DHMF. These results demonstrated a sustainable route to synthesize efficient catalysts by employing metal-organic frameworks based on renewable ligands.


Asunto(s)
Furaldehído , Povidona , Furaldehído/análogos & derivados , Hidrogenación , Ligandos
14.
Front Oncol ; 11: 712041, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34513691

RESUMEN

Metastases are the leading cause of death in cancer patients. RhoC, a member of the Rho GTPase family, has been shown to facilitate metastasis of aggressive breast cancer cells by influencing motility, invasion, and chemokine secretion, but as yet there is no integrated model of the precise mechanism of how RhoC promotes metastasis. A common phenotypic characteristic of metastatic cells influenced by these mechanisms is dysregulation of cell-cell junctions. Thus, we set out to study how RhoA- and RhoC-GTPase influence the cell-cell junctions in aggressive breast cancers. We demonstrate that CRISPR-Cas9 knockout of RhoC in SUM 149 and MDA 231 breast cancer cells results in increased normalization of junctional integrity denoted by junction protein expression/colocalization. In functional assessments of junction stability, RhoC knockout cells have increased barrier integrity and increased cell-cell adhesion compared to wild-type cells. Whole exome RNA sequencing and targeted gene expression profiling demonstrate decreased expression of Type I interferon-stimulated genes in RhoC knockout cells compared to wild-type, and subsequent treatment with interferon-alpha resulted in significant increases in adhesion and decreases in invasiveness of wild-type cells and a dampened response to interferon-alpha stimulation with respect to adhesion and invasiveness in RhoC knockout cells. We delineate a key role of RhoC-GTPase in modulation of junctions and response to interferon, which supports inhibition of RhoC as a potential anti-invasion therapeutic strategy.

15.
ChemSusChem ; 13(3): 548-555, 2020 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-31714031

RESUMEN

The aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA), a promising renewable monomer to produce bio-based polymers such as polyethylene furanoate (PEF), has recently emerged as the subject of increasing interest. Here, holey 2 D Mn2 O3 nanoflakes were obtained by a facile thermal treatment of a Mn-based metal-organic framework (MOF) precursor. The structural and morphological properties of the nanoflakes were characterized by powder XRD, FTIR, SEM and TEM to explore the formation process. It was inferred that the linker loss in the MOF precursor and the oxidation of the Mn cation induced by the heat-treatment in air were responsible for the formation of holey 2 D Mn2 O3 nanoflakes. The specific morphology and redox cycle of the Mn cation on the surface endowed the synthesized nanoflakes with promising performance on the selective oxidation. The obtained nanoflakes calcined at 400 °C (M400) afforded over 99.5 % yield of FDCA at complete conversion of HMF, which is superior to the catalytic activity of commercial Mn2 O3 and activated MnO2 . To our knowledge, Mn2 O3 exhibiting such a high performance on the aerobic oxidation of HMF to FDCA has not yet been reported. Based on the investigation of the experimental parameters, a plausible reaction mechanism was proposed.

16.
Sci Rep ; 10(1): 5781, 2020 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-32238832

RESUMEN

Identifying better predictive and prognostic biomarkers for the diagnosis and treatment of triple negative breast cancer (TNBC) is complicated by tumor heterogeneity ranging from responses to therapy, mutational burden, and clonal evolution. To overcome the gap in our understanding of tumor heterogeneity, we hypothesized that isolating and studying the gene expression profile of invasive tumor cell subpopulations would be a crucial step towards achieving this goal. In this report, we utilized a fluidic device previously reported to be capable of supporting long-term three-dimensional growth and invasion dynamics of cancer cells. Live invading and matched non-invading SUM149 inflammatory breast cancer cells were enriched using this device and these two functionally distinct subpopulations were tested for differences in gene expression using a gene expression microarray. 305 target genes were identified to have altered expression in the invading cells compared to the non-invading tumoroid cells. Gene ontology analysis of the gene panel identified multiple biological roles ranging from extracellular matrix reorganization to modulation of the immune response and Rho signaling. Interestingly, the genes associated with the invasion front differ between different samples, consistent with inter- and intra-tumor heterogeneity. This work suggests the impact of heterogeneity in biomarker discovery should be considered as cancer therapy increasingly heads towards a personalized approach.


Asunto(s)
Regulación Neoplásica de la Expresión Génica , Invasividad Neoplásica/genética , Neoplasias de la Mama Triple Negativas/genética , Biomarcadores de Tumor/genética , Línea Celular Tumoral , Femenino , Perfilación de la Expresión Génica , Ontología de Genes , Heterogeneidad Genética , Humanos , Invasividad Neoplásica/patología , Transcriptoma , Neoplasias de la Mama Triple Negativas/patología , Células Tumorales Cultivadas
17.
Front Oncol ; 9: 456, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31214501

RESUMEN

Tumor associated macrophages (TAMs) are increasingly recognized as major contributors to the metastatic progression of breast cancer and enriched levels of TAMs often correlate with poor prognosis. Despite our current advances it remains unclear which subset of M2-like macrophages have the highest capacity to enhance the metastatic program and which mechanisms regulate this process. Effective targeting of macrophages that aid cancer progression requires knowledge of the specific mechanisms underlying their pro-metastatic actions, as to avoid the anticipated toxicities from generalized targeting of macrophages. To this end, we set out to understand the relationship between the regulation of tumor secretions by Rho-GTPases, which were previously demonstrated to affect them, macrophage differentiation, and the converse influence of macrophages on cancer cell phenotype. Our data show that IL-4/IL-13 in vitro differentiated M2a macrophages significantly increase migratory and invasive potential of breast cancer cells at a greater rate than M2b or M2c macrophages. Our previous work demonstrated that the Rho-GTPases are potent regulators of macrophage-induced migratory responses; therefore, we examined M2a-mediated responses in RhoA or RhoC knockout breast cancer cell models. We find that both RhoA and RhoC regulate migration and invasion in MDA-MB-231 and SUM-149 cells following stimulation with M2a conditioned media. Secretome analysis of M2a conditioned media reveals high levels of vascular endothelial growth factor (VEGF) and chemokine (C-C motif) ligand 18 (CCL-18). Results from our functional assays reveal that M2a TAMs synergistically utilize VEGF and CCL-18 to promote migratory and invasive responses. Lastly, we show that pretreatment with ROCK inhibitors Y-276332 or GSK42986A attenuated VEGF/CCL-18 and M2a-induced migration and invasion. These results support Rho-GTPase signaling regulates downstream responses induced by TAMs, offering a novel approach for the prevention of breast cancer metastasis by anti-RhoA/C therapies.

18.
Bioresour Technol ; 267: 333-340, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30029179

RESUMEN

An efficient method for microwave-assisted low temperature catalytic elimination of primary tars using cheap biochar as catalyst has been developed along with H2 rich syngas production. Tar removal efficiency reached 94.03% after 8 min reaction at 600 °C, while the concentration of H2 and syngas was up to 50.5 vol% and 94.5 vol% respectively, which were significantly comparable to conventional technologies at 700-900 °C. The FT-IR, ICP and EDX results indicated that the biochar surface contained O-containing functional groups and 12.6 wt% uniformly dispersed alkali and alkaline earth metals (AAEMs) in the carbon skeleton. The low temperature behaviours were attributed to the hot spots, which were induced by the increased dielectric properties of biochar and decentralized AAEMs under microwave heating. Possible reaction mechanism for the elimination of primary tars over biochar catalysts were discussed based on this experimental study.


Asunto(s)
Carbón Orgánico , Microondas , Breas , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura
19.
J Control Release ; 289: 79-93, 2018 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-30149048

RESUMEN

Overexpression of RhoC protein in breast cancer patients has been linked to increased cancer cell invasion, migration, and metastases. Suppressing RhoC expression in aggressive breast cancer cells using silencing RNA (siRNA) molecules is a viable strategy to inhibit the metastatic spread of breast cancer. In this report, we describe the synthesis of a series of asymmetric pH-sensitive, membrane-destabilizing polymers engineered to complex anti-RhoC siRNA molecules forming "smart" nanoparticles. Using ß-CD as the particle core, polyethylene glycol (PEG) chains were conjugated to the primary face via non-cleavable bonds and amphiphilic polymers incorporating hydrophobic and cationic monomers were grafted to the secondary face via acid-labile linkages. We investigated the effect of PEG molecular weight (2 & 5 kDa) on transfection capacity and serum stability of the formed particles. We evaluated the efficacy of EPPT1 peptides presented on the free tips of the PEG brush to function as a targeting ligand against underglycosylated MUC1 (uMUC1) receptors overexpressed on the surface of metastatic breast cancer cells. Results show that "smart" nanoparticles successfully delivered anti-RhoC siRNA into the cytoplasm of aggressive SUM149 and MDA-MB-231 breast cancer cells, which resulted in a dose-dependent inhibition of cell migration and invasion. Further, EPPT1-targeted nanoparticles demonstrate a synergistic inhibition of cell migration and invasion imparted via RhoC knockdown and EPPT1-mediated signaling via the uMUC1 receptor.


Asunto(s)
Neoplasias de la Mama/terapia , Nanocápsulas/química , Invasividad Neoplásica/prevención & control , Oligopéptidos/metabolismo , Interferencia de ARN , ARN Interferente Pequeño/administración & dosificación , Proteína rhoC de Unión a GTP/genética , Neoplasias de la Mama/patología , Línea Celular Tumoral , Permeabilidad de la Membrana Celular , Movimiento Celular , Proliferación Celular , Liberación de Fármacos , Femenino , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen/métodos , Humanos , Mucina-1/metabolismo , Oligopéptidos/química , Polietilenglicoles/química , Polimerizacion , Transfección , Microambiente Tumoral , beta-Ciclodextrinas/química , Proteína rhoC de Unión a GTP/metabolismo
20.
ChemSusChem ; 11(15): 2492-2496, 2018 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-29893483

RESUMEN

Formic acid-induced controlled-release hydrolysis of sugar-rich microalgae (Scenedesmus) over the Sn-Beta catalyst was found to be a highly efficient process for producing lactic acid as a platform chemical. One-pot reaction with a very high lactic acid yield of 83.0 % was realized in a batch reactor using water as the solvent. Under the attack of formic acid, the cell wall of Scenedesmus was disintegrated, and hydrolysis of the starch inside the cell was strengthened in a controlled-release mode, resulting in a stable and relatively low glucose concentration. Subsequently, the Sn-Beta catalyst was employed for the efficient conversion of glucose into lactic acid with stable catalytic performance through isomerization, retro-aldol and de-/rehydration reactions. Thus, the hydrolysis of polysaccharides and the catalytic conversion of the monosaccharide into lactic acid was realized by the combination of an organic Brønsted acid and a heterogeneous Lewis acid catalyst.


Asunto(s)
Formiatos/metabolismo , Ácido Láctico/metabolismo , Scenedesmus/metabolismo , Estaño/química , Catálisis , Glucosa/química , Glucosa/metabolismo , Hidrólisis , Isomerismo , Ácidos de Lewis/química , Microscopía Electrónica de Transmisión , Scenedesmus/ultraestructura , Solventes/química , Agua
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