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Current cancer studies focus on molecular-targeting diagnostics and interactions with surroundings; however, there are still gaps in characterization based on topological differences and elemental composition. Glioblastoma (GBM cells; GBMCs) is an astrocytic aggressive brain tumor. At the molecular level, GBMCs and astrocytes may differ, and cell elemental/topological analysis is critical for identifying potential new cancer targets. Here, we used U87 MG cells for GBMCS. U87 MG cell lines, which are frequently used in glioblastoma research, are an important tool for studying the various features and underlying mechanisms of this aggressive brain tumor. For the first time, atomic force microscopy (AFM), scanning electron microscopy (SEM) accompanied by energy-dispersive X-ray spectroscopy (EDS), and X-ray photoelectron spectroscopy (XPS) are used to report the topology and chemistry of cancer (U87 MG) and healthy (SVG p12) cells. In addition, F-actin staining and cytoskeleton-based gene expression analyses were performed. The degree of gene expression for genes related to the cytoskeleton was similar; however, the intensity of F-actin, anisotropy values, and invasion-related genes were different. Morphologically, GBMCs were longer and narrower while astrocytes were shorter and more disseminated based on AFM. Furthermore, the roughness values of these cells differed slightly between the two call types. In contrast to the rougher astrocyte surfaces in the lamellipodial area, SEM-EDS analysis showed that elongated GBMCs displayed filopodial protrusions. Our investigation provides considerable further insight into rapid cancer cell characterization in terms of a combinatorial spectroscopic and microscopic approach.
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Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/metabolismo , Astrocitos/metabolismo , Astrocitos/patología , Actinas , Línea Celular Tumoral , Neoplasias Encefálicas/patologíaRESUMEN
Melanoma is an aggressive tumor with a poor prognosis that worsens in the metastatic phase. Distruptions of epigenetic mechanisms is known to effect cancer stem cells (CSCs) activity. Malignant melanoma (MM) progression may be promoted by changes in the genetic structure of CSC. Thus, treatments that target epigenetic modifications could be a promising weapon, especially in melanoma. Here, we compared p300, HDAC9, and F-actin proteins in melanoma CSCs (CD133+), non-CSCs (CD133-) and CHL-1 cell line, as well as cell migration and division rates. At 4 and 6 h, P300 protein levels in CHL-1 and CD133 + were remarkably similar, and the CD133- showed increases in expression levels as the incubation period lengthened. HDAC9 protein intensity decreased in CHL-1, increased in the CD133-, and remained relatively unchanged in the CD133+ as the incubation period lengthened. The mean value of F-actin expression level increased in all cell group with time, when the highest increase observed in CHL-1. In conclusion, our studies contribute to the management of metastatic diseases in the future and offer new insight into the molecular basis of the initiation and progression of MM.
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AIM: To evaluate the effects of c-Jun N-terminal kinase (JNK) inhibition and signal blocking on hypoxia (hypoxia-inducible factor 1-alpha (HIF-1α)), differentiation and neurogenesis (bone morphogenetic protein (BMP4)), and the cytoskeleton (F-actin) in glioblastoma multiforme cells (GBMCs). MATERIAL AND METHODS: We evaluated the differences between GBMCs and astrocytes in terms of the abovementioned parameters and assessed them with the aim of studying human GBMCs (U-87 MG) and astrocytes (SVG p12). The cells were exposed to different doses of the JNK inhibitor, SP600125, for 24, 48, and 72 hours. HIF-1α, BMP4, and F-actin expressions were evaluated using immunofluorescence image analysis. RESULTS: The half-maximal inhibitory concentration value for SP600125 was determined to be 10 µM at 24 hours of exposure. After SP600125 administration, elevated levels of HIF-1α and BMP4 were detected in GBMCs and astrocytes. F-actin level only increased in GBMCs after SP600125 administration. CONCLUSION: JNKs are important for cell proliferation, differentiation, survival, and death; thus, research on JNKs has become important for the treatment of many human diseases, especially brain tumors, Parkinson's disease, and Alzheimer's disease. The results of this study involving immunofluorescence techniques should be investigated and supported by studies that involve comprehensive molecular techniques.
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Glioblastoma , Humanos , Glioblastoma/patología , Astrocitos , Actinas/metabolismo , Hipoxia/metabolismo , Citoesqueleto/metabolismo , Citoesqueleto/patología , Neurogénesis , Técnica del Anticuerpo FluorescenteRESUMEN
Malignant tumors are formed by diverse groups of cancer cells. Cancer stem cells (CSCs) are a subpopulation of heterogeneous cells identified in tumors that have the ability to self-renew and differentiate. Colorectal cancer (CRC), the third most frequent malignant tumor, is progressively being supported by evidence suggesting that CSCs are crucial in cancer development. We aim to identify molecular differences between CRC cells and CRC CSCs, as well as the effects of those differences on cell behavior in terms of migration, EMT, pluripotency, morphology, cell cycle/control, and epigenetic characteristics. The HT-29 cell line (human colorectal adenocarcinoma) and HT-29 CSCs (HT-29 CD133+/CD44+ cells) were cultured for 72 h. The levels of E-cadherin, KLF4, p53, p21, p16, cyclin D2, HDAC9, and P300 protein expression were determined using immunohistochemistry staining. The migration of cells was assessed by employing the scratch assay technique. Additionally, the scanning electron microscopy method was used to examine the morphological features of the cells, and their peripheral/central elemental ratios were compared with the help of EDS. Furthermore, a Muse cell cycle kit was utilized to determine the cell cycle analysis. The HT-29 CSC group exhibited high levels of expression for E-cadherin, p53, p21, p16, cyclin D2, HDAC9, and P300, whereas KLF4 was found to be high in the HT-29. The two groups did not exhibit any statistically significant differences in the percentages of cell cycle phases. The identification of specific CSC characteristics will allow for earlier cancer detection and the development of more effective precision oncology options.
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PURPOSE: Papillary thyroid carcinoma (PTC) is the most common type of thyroid cancer and accounts for 85-90% of all thyroid cancers. Metastatic differentiated thyroid cancer, radioiodine-refractory thyroid cancer, and anaplastic thyroid cancer still lack effective therapeutic options. Here, we aimed to assess HDAC9 and P300 expression in the papillary thyroid carcinoma cell line and compare them with normal thyroid cells. METHODS: Nthy-ori-3-1, a normal thyroid cell line, and BCPAP, a PTC cell line, were cultured for 24 and 48 h and immunofluorescence staining was used to determine the levels of HDAC9 and P300 protein expression. HDAC9 paracrine release was assessed using an ELISA assay. RESULTS: HDAC9 protein expression was higher in both cell groups at the 48th hour than at the 24th hour; however, P300 protein expression was lower in BCPAP cells at the 48th hour than at the 24th hour. In comparison to Nthy-ori-3-1, BCPAP expressed more HDAC9 and P300 proteins. HDAC9 secretion slightly increased in Nthy-ori-3-1 cells from 24 to 48 h. Furthermore, HDAC9 secretion in BCPAP cells dramatically decreased from 24 to 48 h. CONCLUSION: Our findings revealed that the expression of HDAC9 and P300 was higher in the PTC cell line than in normal thyroid cells. This indicates that the acetylation mechanism in thyroid cancer cells is not the same as it is in healthy cells. Epigenetic studies may reveal the mechanisms underlying PTC with further analysis.
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Carcinoma Papilar , Neoplasias de la Tiroides , Humanos , Cáncer Papilar Tiroideo , Radioisótopos de Yodo , Línea Celular Tumoral , Proliferación Celular , Carcinoma Papilar/patología , Neoplasias de la Tiroides/patología , Histona Desacetilasas , Proteínas RepresorasRESUMEN
BACKGROUND: Thyroid cancer is the most frequent type of endocrine malignancy. Thyroid carcinomas are derived from the follicular epithelium and classified as papillary (PTC) (85%), follicular (FTC) (12%), and anaplastic (ATC) (<3%). Thyroid cancer could arise from thyroid cancer stem-like cells (CSCs). CSCs are cancer cells that feature stem-like properties. Kruppel-like factor (KLF4) and Stage-spesific embryonic antigen 1 (SSEA-1) are types of stem cell markers. Filamentous actin (F-actin) is an essential part of the cellular cytoskeleton. The purpose of this study was to evaluate the stem cell potency and the spatial distribution of the cytoskeletal element F-actin in PTC, FTC, and ATC cell lines. MATERIALS AND METHODS: Normal thyroid cell line (NTC) Nthy-ori-3-1, PTC cell line BCPAP, FTC cell line FTC-133 and ATC cell line 8505c were stained with SSEA-1 and KLF4 for stem cell potency and F-actin for cytoskeleton. The morphological properties of cells were assessed by a scanning electron microscope (SEM) and elemental ratios were compared with EDS. RESULTS: PTCs had greater percentages of SSEA-1 and KLF4 protein intensity (0.32% and 0.49%, respectively) than NTCs. ATCs had a greater proportion of KLF4 expression (0.8%) than NTCs. NTCs and FTCs had increased F-actin intensity across the cell, but PTCs had the lowest among these four cell lines. NTCs and PTCs, as well as NTCs and FTCs, have statistically identical aspect ratios and round values. These values, however, were statistically different in ATCs. CONCLUSION: The study of stem cell markers and the cytoskeletal element F-actin in cancer and normal thyroid cell lines may assist in the identification of new therapeutic targets and contribute in the understanding of treatment resistance mechanisms.
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Actinas , Neoplasias de la Tiroides , Humanos , Neoplasias de la Tiroides/patología , Línea Celular , Factores de Transcripción de Tipo Kruppel , Antígeno Lewis XRESUMEN
BACKGROUND: Glioblastoma (GBM) is the most aggressive brain tumor contributed to tumor growth by cancer stem cells (CSCs). Targeting CSCs is vital to preventing differentiation into cancer cells, their proliferation, and treatment resistance. According to research, PI3K/AKT/mTOR signaling is active in GBM and GBMCSCs. Anticancer medications combined with ultrasound application have been proposed as a strategy to increase the drug intake of cancer cells. This study aims to investigate the effects of inhibition of PI3K/ AKT/ mTOR pathway with dual inhibitor Voxtalisib (Vox; also known as XL765) and low intensity pulsed ultrasound (LIPUS) combinations in GBM and GBMCSCs in the point of cell survival. F-actin was also used to evaluate cell motility. MATERIALS AND METHODS: GBMCSCs were isolated from the human glioblastoma U87 MG cell line using the fluorescence-activated cell sorting (FACS) method. Cells were exposed to various concentrations of Vox, LIPUS, and their combinations. Cell count and viability assay was used to determine drug delivery doses. F-actin and mTOR immunofluorescence staining were used to identify cytoskeletal alterations and PI3K/AKT/mTOR signal pathway suppression, respectively. Additionally, the migration capacity of cells was shown with standard wound-healing experiments. RESULTS: High doses of Vox+LIPUS inhibited mTOR and decreased the viability in both cell groups. Inhibiting mTOR activated autophagy, and LIPUS increased autophagy in GBM cells. However, GBMCSCs were resistant to autophagy even at high drug dosages. Both in GBM and GBMCSCs, combinations of Vox and LIPUS were observed to decrease F-actin density and cell motility. CONCLUSIONS: The combination of Vox+LIPUS has increased drug effectiveness in targeted GBM and GBMCSCs. Combinatory treatment with PI3K/AKT/mTOR signaling pathway and LIPUS has been thought to help develop more effective therapeutic approaches for GBM.
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Glioblastoma , Humanos , Glioblastoma/patología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Actinas , Proliferación Celular , Línea Celular Tumoral , Serina-Treonina Quinasas TOR/metabolismo , Células Madre Neoplásicas/patología , Ondas UltrasónicasRESUMEN
Endoplasmic reticulum (ER) stress has been reported to play a role in the pathogenesis of intrauterine growth retardation and preeclampsia, especially implantation failure. Although in vitro ER stress studies in human trophoblast cell line have been conducted in recent years, the influence of Thapsigargin on intracellular dynamics on calcium homeostasis has not been proven. Here, the effects of ER stress and impaired calcium homeostasis on apoptosis, autophagy, cytoskeleton, hypoxia, and adhesion molecules in 2D and spheroid cultures of human trophectoderm cells were investigated at gene expression and protein levels. Thapsigargin caused ER stress by increasing GRP78 gene expression and protein levels. Human trophectoderm cells displayed different characterization properties in 2D and spheroids. While it moves in the pathway of EIF2A and IRE1A mechanisms in 2D, it proceeds in the pathway of EIF2A and ATF6 mechanisms in spheroids and triggers different responses in survival and programmed cell death mechanisms such as apoptosis and autophagy. This led to changes in the cytoskeleton, cell adhesion molecules and cell-cell interactions by affecting the hypoxia mechanism.
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Estrés del Retículo Endoplásmico , Trofoblastos , Calcio/metabolismo , Femenino , Humanos , Hipoxia/metabolismo , Embarazo , Tapsigargina/metabolismo , Tapsigargina/farmacología , Trofoblastos/metabolismoRESUMEN
While embryonic stem cells and cancer cells are known to have many similarities in signalling pathways, healthy somatic cells are known to be different in many ways. Characterization of embryonic stem cell is crucial for cancer development and cancer recurrence due to the shared signalling pathways and life course with cancer initiator and cancer stem cells. Since embryonic stem cells are the sources of the somatic and cancer cells, it is necessary to reveal the relevance between them. The past decade has seen the importance of interdisciplinary studies and it is obvious that the reflection of the physical/chemical phenomena occurring on the cell biology has attracted much more attention. For this reason, the aim of this study is to elementally and topologically characterize the mouse embryonic stem cells, mouse lung squamous cancer cells, and mouse skin fibroblast cells by using Atomic Force Microscopy (AFM), X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM) supported with Electron Dispersive Spectroscopy (EDS) techniques in a complementary way. Our AFM findings revealed that roughness data of the mouse embryonic stem cells and cancer cells were similar and somatic cells were found to be statistically different from these two cell types. However, based on both XPS and SEM-EDS results, surface elemental ratios vary in mouse embryonic stem cells, cancer cells and somatic cells. Our results showed that these complementary spectroscopic and microscopic techniques used in this work are very effective in cancer and stem cell characterization and have the potential to gather more detailed information on relevant biological samples.
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Fibroblastos , Neoplasias Pulmonares , Células Madre Embrionarias de Ratones , Neoplasias de Células Escamosas , Piel , Animales , Línea Celular Tumoral , Fibroblastos/metabolismo , Fibroblastos/ultraestructura , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/ultraestructura , Ratones , Microscopía de Fuerza Atómica , Microscopía Electroquímica de Rastreo , Células Madre Embrionarias de Ratones/metabolismo , Células Madre Embrionarias de Ratones/ultraestructura , Neoplasias de Células Escamosas/metabolismo , Neoplasias de Células Escamosas/ultraestructura , Piel/metabolismo , Piel/ultraestructuraRESUMEN
Cancer stem cells (CSCs), which act as an important bridge between cancer formation and embryonic development, represent a small population associated with tumor initiation, drug resistance, metastasis and recurrence. CSCs have the ability to form spheroids in three-dimensional culture systems. Tumor spheroids derived from CSCs with symmetric and asymmetric division patterns were found to contain highly heterogeneous cell groups. The biological behavior patterns which some CSCs display serve as an important bridge between cancer formation and embryonic development. The cell population in the DU-145 prostate cancer cell line with surface markers CD133+/CD44+ was isolated by FACS. Prostate spheroids were formed by using agarose-coated plates. The morphological characteristics of the cell population within spheroid structure and the expression of Ki-67 and Caspase-3 were investigated by histochemical methods. In this study, we observed that CD133+/CD44+ prostate CSCs form different spheroid structures as well as normal spheroid structures: i) some spheroid structures formed with a highly transparent zone on the outer part of the spheroid, in addition to the normal spheroidal zones and ii) spheroidal structures obtained from prostate CD1334+/CD44+ CSCs that share the same microenvironment are hollow spheres similar to the blastula-like structure in the embryo. These spheroidal structures exhibiting embryo-like properties indicate that the expression of embryonic factors might be reiterated in CSCs. Further investigation of the formation mechanism of the transparent zone and the hollow sphere will shed light on the embryonic origin of prostate cancer and the design of new therapeutic strategies.
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Antígeno AC133/biosíntesis , Regulación Neoplásica de la Expresión Génica , Receptores de Hialuranos/biosíntesis , Células Madre Neoplásicas/metabolismo , Neoplasias de la Próstata/metabolismo , Apoptosis , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Proliferación Celular , Separación Celular , Células Madre Embrionarias/citología , Citometría de Flujo , Humanos , Técnicas In Vitro , Masculino , Necrosis , Esferoides Celulares , Microambiente TumoralRESUMEN
PIKfyve is an evolutionarily conserved lipid and protein kinase enzyme that has pleiotropic cellular functions. The aim of the present study was to investigate the effects of phosphatidylinositol-3-phosphate 5-kinase (PIKfyve) inhibitor, YM201636, on nonsmall cell lung cancer (NSCLC) cells growth, tumorigenicity, and claudin (CLDN) expressions. Three NSCLC cell lines (Calu-1, H1299 and HCC827) were used to compare the effects of YM201636. Cytotoxic effects of YM201636 were analysed using XTT assay. Malignancy potential of cells assesses with wound healing and soft agar colony-forming assays. mRNA and protein expressions of claudins were analysed by qRT-PCR and immunofluorescence staining. Our results revealed that YM201636 inhibited the proliferation and malignancy potential of Calu-1, H1299, and HCC827 cells in a dose-dependent manner. After YM201636 treatment CLDN1, -3 and -5 expressions increased significantly in HCC827 cells. CLDN3 and -5 expressions also significantly increased in Calu1 cell line. YM201636 treatment significantly reduced the CLDN1 and increased the CLDN5 expression in H1299 cells. Immunofluorescence staining of CLDN1, -3 and -5 proteins showed a significant increase after YM201636 treatment. Besides, YM201636 induced EGFR mRNA expression in all NSCLC cell lines. Our results have shown that YM201636 inhibits tumorigenicity of NSCLC cells. Furthermore, estimated glomerular filtration rate (EGFR) pathway is important signalling involved in the regulation of claudins. Understanding the mechanisms of PIKfyve inhibitors may improve cancer treatment particularly for EGFR overactivated NSCLC.
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Embryonic stem cells (ESCs) are promising research materials to investigate cell fate determination since they have the capability to differentiate. Stem cell differentiation has been extensively studied with various microenvironment mimicking structures to modify cellular dynamics associated with the cell-extracellular matrix (ECM) interactions and cell-cell communications. In the current study, our aim was to determine the effect of microenvironmental proteins with different concentrations on the capacity and differentiation capability of mouse ESCs (mESCs), combining the biochemical assays, imaging techniques, Fourier transform infrared (FTIR) spectroscopy, and unsupervised multivariate analysis. Based on our data, coating the surface of mESCs with Matrigel, used as an acellular matrix substrate, resulted in morphological and biochemical changes. mESCs exhibited alterations in their phenotype after growing on the Matrigel-coated surfaces, including their differentiation capacity, cell cycle phase pattern, membrane fluidity, and metabolic activities. In conclusion, mESCs can be stimulated physiologically, chemically, or mechanically to convert them a new phenotype. Thus, identification of ESCs' behavior in the acellular microenvironment could be vital to elucidate the mechanism of diseases. It might also be promising to control the cell fate in the field of tissue engineering.
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Diferenciación Celular , Matriz Extracelular/metabolismo , Células Madre Embrionarias de Ratones/citología , Células Madre Embrionarias de Ratones/metabolismo , Ingeniería de Tejidos/métodos , Animales , Comunicación Celular , División Celular , Linaje de la Célula , Ratones , Microscopía de Fuerza Atómica , Microscopía de Contraste de Fase , Análisis Multivariante , Fenotipo , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de SuperficieRESUMEN
Cancer is a group of diseases of our era that affects not only medical status but also lowers the tone of social and emotional well-being. It also has severe impacts on economies. Cancer cells are linked to the somatic cells and stem cells, with their characteristic similarities and differences. Variations in cell-signaling pathways, such as cell death and proliferation balances, kinetic behavior of the cells, and their differentiation potentials, are the featured parameters for therapeutic targeting. The detection of target points should be based not only on the molecular biology methods but also on the physical and topological analyses from the aspect of "geography is fate". In this review, we focus on the importance of the holistic analyses of intracellular and extracellular dynamics and multidisciplinary cooperation.
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Transformación Celular Neoplásica , Susceptibilidad a Enfermedades , Neoplasias/etiología , Neoplasias/metabolismo , Animales , Biomarcadores , Ciclo Celular/genética , Diferenciación Celular , Proliferación Celular , Autorrenovación de las Células , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Transición Epitelial-Mesenquimal/genética , Humanos , Neoplasias/patología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Células Madre/citología , Células Madre/metabolismoRESUMEN
Embryonic developmental stages and regulations have always been one of the most intriguing aspects of science. Since the cancer stem cell discovery, striking for cancer development and recurrence, embryonic stem cells and control mechanisms, as well as cancer cells and cancer stem cell control mechanisms become important research materials. It is necessary to reveal the similarities and differences between somatic and cancer cells which are formed of embryonic stem cells divisions and determinations. For this purpose, mouse embryonic stem cells (mESCs), mouse skin fibroblast cells (MSFs) and mouse lung squamous cancer cells (SqLCCs) were grown in vitro and the differences between these three cell lines signalling regulations of mechanistic target of rapamycin (mTOR) and autophagic pathways were demonstrated by immunofluorescence and real-time polymerase chain reaction. Expressional differences were clearly shown between embryonic, cancer and somatic cells that mESCs displayed higher expressional level of Atg10, Hdac1 and Cln3 which are related with autophagic regulation and Hsp4, Prkca, Rhoa and ribosomal S6 genes related with mTOR activity. LC3 and mTOR protein levels were lower in mESCs than MSFs. Thus, the mechanisms of embryonic stem cell regulation results in the formation of somatic tissues whereas that these cells may be the causative agents of cancer in any deterioration.
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Autofagia , Fibroblastos/patología , Neoplasias Pulmonares/patología , Células Madre Embrionarias de Ratones/patología , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo , Animales , Autofagia/genética , Línea Celular , Fibroblastos/metabolismo , Regulación de la Expresión Génica , Neoplasias Pulmonares/metabolismo , Ratones , Proteínas Asociadas a Microtúbulos/metabolismo , Células Madre Embrionarias de Ratones/metabolismoRESUMEN
Cell adhesion to the extracellular matrix is deregulated in metastasis. However, traditional surfaces used to study cell adhesion do not faithfully mimic the in vivo microenvironment. Electron beam lithography (EBL) is able to generate customized protein nanopatterns. Here, we used an EBL-based green lithography approach to fabricate homogeneous and gradient, single (fibronectin, K-casein) and double (fibronectin, laminin) active component protein nanopatterns with micrometer scale spacing to investigate differences in adhesion of breast cancer cells (BCC) and normal mammary epithelial cells (NMEC). Our results showed that as expected, in contrast to NMEC, BCC were plastic: they tolerated nonadhesion promoting regions, adapted to flow and exploited gradients better. In addition, the number of focal adhesions but not their area appeared to be the dominant parameter for regulation of cell adhesion. Our findings also demonstrated that custom designed protein nanopatterns, which can properly mimic the in vivo microenvironment, enable realistic distinction of normal and cancerous cell adhesion.
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Neoplasias de la Mama/patología , Mama/patología , Nanoestructuras , Adhesión Celular , Línea Celular , Línea Celular Tumoral , Forma de la Célula , Células Epiteliales/citología , Diseño de Equipo , Femenino , Fibronectinas/química , Adhesiones Focales/patología , Humanos , Laminina/química , Nanoestructuras/química , Nanotecnología , Propiedades de SuperficieRESUMEN
Focal adhesions (FAs) are specialized adhesive structures which serve as cellular communication units between cells and the surrounding extracellular matrix. FAs are involved in signal transduction and actin cytoskeleton organization. FAs mediate cell adhesion, which is a critical phenomenon in cancer research. Since cells can form many and micrometer scale FAs, their quantitative analysis demands well-optimized image analysis approaches [1-3]. Here, we have optimized the analysis of FAs of MDA-MB-231 breast cancer cells. The optimization is based on proper processing of immunofluorescence images of vinculin, which is one of the markers of FAs. All image processing steps are carried out using the ImageJ software, which is freely available and in the public domain. The advantages of our method are:â¢The analysis steps are simplified by combining different plugins of the ImageJ program.â¢FAs are better detected with minimal false negatives due to optimized processing of fluorescent images.â¢This approach can be applied to quantify a variety of fluorescent images comprising focal and/or localized signals within a high background such as FAs, one of the many complex signaling structures in a cell.
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Microfluidics-based lab-on-a-chips have many advantages, one of which is to provide physiologically relevant settings for cell biology experiments. Thus there is an ever increasing interest in their fabrication. Our goal is to construct three dimensional (3D) Controlled in vitro Microenvironments (CivMs) that mimic the in vivo microenvironments. Here, we present our optimized fabrication method that works for various lab-on-a-chip designs with a wide range of dimensions. The most crucial points are:â¢While using one type of SU-8 photoresist (SU-2075), fine tuning of ramp, dwell time, spin speed, durations of soft bake, UV exposure and development allows fabrication of SU-8 masters with various heights from 40 to 600 µm.â¢Molding PDMS (polydimethylsiloxane) at room temperature for at least two days instead of baking at higher temperatures prevents not only tears and bubbles in PDMS stamps but also cracks in the SU-8 master.â¢3D nature of the CivMs is ensured by keeping the devices inverted during gel polymerization.