RESUMEN
INTRODUCTION: Solid variant papillary thyroid cancer (SVPTC) is a rare variant of papillary thyroid carcinoma (PTC) and its prognostic value is still unclear. Therefore, we re-evaluate the histopathological and clinicopathological features of 28 patients with SVPTC in the light of current literature. MATERIAL-METHODS: Of the 1308 cases were previously diagnosed with PTC and 28 (2,1%) of them which had been diagnosed with SVPTC were re-evaluated retrospectively. RESULTS: Of the 28 patients with SVPTC, 85.7% were female, mean age was 45.18 years and mean tumor diameter was 2.96 cm. Microscopically; tumors had a solid growth pattern amounting to at least 50.0% of the tumor volume. In all cases the tumor cells had characteristic nuclear features of conventional PTC. 11 patients had multifocal tumors, extrathyroidal extension was present in 4 patients and vascular invasion was observed in 7 cases. Regional lymph node metastases were noted in 2 (7.1%) cases at the time of diagnosis. One patient died because of locally advanced disease. Another patient is alive with lung metastases after 48 months from the initial surgery. There was no evidence of local recurrence in other patient. CONCLUSIONS: SVPTC is a rare variant of PTC that should be considered in the differential diagnosis of tumors which show a solid/trabecular growth pattern in the thyroid. It has poor prognostic features such as widespread angioinvasion, extrathyroidal extention, lymph node metastasis, and distant organ metastasis. Multicenter studies involving large number of cases are needed to reveal the prognostic significance of SVPTC, with standardized diagnostic criteria.
Asunto(s)
Línea Celular Tumoral/ultraestructura , Cáncer Papilar Tiroideo/diagnóstico , Glándula Tiroides/patología , Neoplasias de la Tiroides/patología , Adolescente , Adulto , Anciano , Línea Celular Tumoral/patología , Diagnóstico Diferencial , Femenino , Humanos , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/patología , Pronóstico , Estudios Retrospectivos , Cáncer Papilar Tiroideo/mortalidad , Carga TumoralRESUMEN
PURPOSE: Patients with central nervous system (CNS) tumors are typically treated with radiotherapy, but this is not curative and results in the upregulation of phosphorylated STAT3 (p-STAT3), which drives invasion, angiogenesis, and immune suppression. Therefore, we investigated the combined effect of an inhibitor of STAT3 and whole-brain radiotherapy (WBRT) in a murine model of glioma. EXPERIMENTAL DESIGN: C57BL/6 mice underwent intracerebral implantation of GL261 glioma cells, WBRT, and treatment with WP1066, a blood-brain barrier-penetrant inhibitor of the STAT3 pathway, or the two in combination. The role of the immune system was evaluated using tumor rechallenge strategies, immune-incompetent backgrounds, immunofluorescence, immune phenotyping of tumor-infiltrating immune cells (via flow cytometry), and NanoString gene expression analysis of 770 immune-related genes from immune cells, including those directly isolated from the tumor microenvironment. RESULTS: The combination of WP1066 and WBRT resulted in long-term survivors and enhanced median survival time relative to monotherapy in the GL261 glioma model (combination vs. control P < 0.0001). Immunologic memory appeared to be induced, because mice were protected during subsequent tumor rechallenge. The therapeutic effect of the combination was completely lost in immune-incompetent animals. NanoString analysis and immunofluorescence revealed immunologic reprograming in the CNS tumor microenvironment specifically affecting dendritic cell antigen presentation and T-cell effector functions. CONCLUSIONS: This study indicates that the combination of STAT3 inhibition and WBRT enhances the therapeutic effect against gliomas in the CNS by inducing dendritic cell and T-cell interactions in the CNS tumor.
Asunto(s)
Neoplasias Encefálicas/terapia , Comunicación Celular/inmunología , Quimioradioterapia/métodos , Glioma/terapia , Factor de Transcripción STAT3/antagonistas & inhibidores , Animales , Presentación de Antígeno/efectos de los fármacos , Presentación de Antígeno/efectos de la radiación , Neoplasias Encefálicas/inmunología , Neoplasias Encefálicas/patología , Comunicación Celular/efectos de los fármacos , Comunicación Celular/efectos de la radiación , Línea Celular Tumoral/ultraestructura , Células Dendríticas/efectos de los fármacos , Células Dendríticas/inmunología , Células Dendríticas/efectos de la radiación , Modelos Animales de Enfermedad , Glioma/inmunología , Glioma/patología , Humanos , Memoria Inmunológica/efectos de los fármacos , Ratones , Piridinas/administración & dosificación , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/efectos de la radiación , Microambiente Tumoral/efectos de los fármacos , Microambiente Tumoral/inmunología , Microambiente Tumoral/efectos de la radiación , Tirfostinos/administración & dosificaciónRESUMEN
RESUMEN: El cáncer de mama es la principal causa de muerte debido al cáncer en mujeres. La microscopía electrónica permite establecer características constitutivas de las células entre diferentes poblaciones celulares. Las células madre del cáncer mamario con inmunofenotipo CD44alta/CD24baja son una población de células intratumorales asociada a la quimioresistencia y metástasis, cuya ultraestructura aún no ha sido bien estudiada. El objetivo de este trabajo fue conocer características ultraestructurales de células con fenotipo de células madre del cáncer de la línea celular MDA-MB-436 de tumor mamario triple negativo comparándolas con células madre adiposas. Se utilizó microscopía electrónica de barrido y de transmisión. Previamente, mediante separación inmunomagnética positiva empleando anticuerpos anti CD44 y anti CD24 unidos a perlas magnéticas, se obtuvo una población de células con fenotipo CD44alta/CD24baja a partir de 10x106 células de la línea MDA-MB-436, la cual igual que las células madre adiposas fue cultivada en cubreobjetos para microscopía electrónica de barrido; en tanto que para microscopía electrónica de transmisión se obtuvo un pellet de células, luego se fijó con glutaraldehído al 2,5 % y post fijó con OsO4 1 %. Para microscopía óptica de alta resolución se usó azul de toluidina como tinción. Luego de obtener el fenotipo de células madre del cáncer se corroboró su pluripotencia detectando la expresión de los genes Oct4 y nanog mediante RT-PCR. Nuestros resultados muestran que las células de este fenotipo son pequeñas, redondeadas, recubiertas por microvellosidades abundantes pero cortas; el citoplasma tiene organelas de secreción celular y abundantes mitocondrias alargadas; el núcleo es excéntrico ocupando la mitad del volumen celular, el nucléolo es voluminoso y la heterocromatina está adosada a la membrana nuclear interna. Se concluye que el inmunofenotipo celular estudiado es una sub población celular dentro de la línea estudiada que difiere en tamaño y ultraestructura de las células madre adiposas.
SUMMARY: Breast cancer is the leading cause of cancer deaths in women. Electron microscopy allows establishing constitutive characteristics of cells between different cell populations. CD44 high / CD24 low mammary cancer stem cells are a population of intratumoral cells associated with chemoresistance and metastasis, whose ultrastructure has not yet been well studied. The objective of this work was to know the ultrastructural characteristics of cells with cancer stem cell phenotype, of the triple negative mammary tumor cell line MDAMB-436 436 using scanning and transmission electron microscopy, and to contrast them with adipose-derived mesenchymal stem cells. Previously, by immunomagnetic purification using anti CD44 and anti CD24 antibodies bound to magnetic beads, cells populations was obtained from 10x106 cells of the MDA-MB-436 line, which, adipose-derived mesenchymal stem whereas cultivated on coverslips for scanning electron microscopy; while for transmission electron microscopy a cell pellet was obtained, then fixed with 2.5 % glutaraldehyde and post fixed with OsO4 1 %. For high resolution optical microscopy, toluidine blue was used as staining. After obtaining the phenotype of cancer stem cells, their pluripotency was corroborated by detecting the expression of the Oct4 and nanog genes by RT-PCR. Our results show that the cells of this phenotype are small, rounded, covered by abundant but short microvilli; the cytoplasm has organelles of cellular secretion and abundant elongated mitochondria; the nucleus is eccentric occupying half of the cellular volume, the nucleolus is bulky and the heterochromatin is attached to the inner nuclear membrane. It is concluded that the cellular immunophenotype studied is a sub-cellular population within the line studied that differs in size and ultrastructure of the adipose stem cells.
Asunto(s)
Humanos , Femenino , Células Madre Neoplásicas/ultraestructura , Neoplasias de la Mama/patología , Microscopía Electrónica , Inmunofenotipificación , Línea Celular Tumoral/ultraestructura , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
Progressive meningiomas that have failed surgery and radiation have a poor prognosis and no standard therapy. While meningiomas are more common in females overall, progressive meningiomas are enriched in males. We performed a comprehensive molecular characterization of 169 meningiomas from 53 patients with progressive/high-grade tumors, including matched primary and recurrent samples. Exome sequencing in an initial cohort (n = 24) detected frequent alterations in genes residing on the X chromosome, with somatic intragenic deletions of the dystrophin-encoding and muscular dystrophy-associated DMD gene as the most common alteration (n = 5, 20.8%), along with alterations of other known X-linked cancer-related genes KDM6A (n =2, 8.3%), DDX3X, RBM10 and STAG2 (n = 1, 4.1% each). DMD inactivation (by genomic deletion or loss of protein expression) was ultimately detected in 17/53 progressive meningioma patients (32%). Importantly, patients with tumors harboring DMD inactivation had a shorter overall survival (OS) than their wild-type counterparts [5.1 years (95% CI 1.3-9.0) vs. median not reached (95% CI 2.9-not reached, p = 0.006)]. Given the known poor prognostic association of TERT alterations in these tumors, we also assessed for these events, and found seven patients with TERT promoter mutations and three with TERT rearrangements in this cohort (n = 10, 18.8%), including a recurrent novel RETREG1-TERT rearrangement that was present in two patients. In a multivariate model, DMD inactivation (p = 0.033, HR = 2.6, 95% CI 1.0-6.6) and TERT alterations (p = 0.005, HR = 3.8, 95% CI 1.5-9.9) were mutually independent in predicting unfavorable outcomes. Thus, DMD alterations identify a subset of progressive/high-grade meningiomas with worse outcomes.
Asunto(s)
Distrofina/genética , Eliminación de Gen , Neoplasias Meníngeas/genética , Meningioma/genética , Anciano , Anciano de 80 o más Años , Línea Celular Tumoral/patología , Línea Celular Tumoral/ultraestructura , Estudios de Cohortes , Progresión de la Enfermedad , Distrofina/metabolismo , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Neoplasias Meníngeas/diagnóstico por imagen , Neoplasias Meníngeas/patología , Meningioma/diagnóstico por imagen , Meningioma/patología , Microscopía Electrónica de Transmisión , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex , ARN Mensajero/metabolismo , Cromatina Sexual/genética , Telomerasa/genética , Telomerasa/metabolismo , Secuenciación del ExomaRESUMEN
Surface-enhanced Raman scattering (SERS)-based cancer diagnostics is an important analytical tool in early detection of cancer. Current work in SERS focuses on plasmonic nanomaterials that suffer from coagulation, selectivity, and adverse biocompatibility when used in vitro, limiting this research to stand-alone biomolecule sensing. Here we introduce a label-free, biocompatible, ZnO-based, 3D semiconductor quantum probe as a pathway for in vitro diagnosis of cancer. By reducing size of the probes to quantum scale, we observed a unique phenomenon of exponential increase in the SERS enhancement up to ~106 at nanomolar concentration. The quantum probes are decorated on a nano-dendrite platform functionalized for cell adhesion, proliferation, and label-free application. The quantum probes demonstrate discrimination of cancerous and non-cancerous cells along with biomolecular sensing of DNA, RNA, proteins and lipids in vitro. The limit of detection is up to a single-cell-level detection.
Asunto(s)
Técnicas de Diagnóstico Molecular/métodos , Sondas Moleculares/química , Neoplasias/diagnóstico , Puntos Cuánticos/química , Semiconductores , Espectrometría Raman/métodos , Animales , Materiales Biocompatibles , Adhesión Celular , Línea Celular/ultraestructura , Línea Celular Tumoral/ultraestructura , Proliferación Celular , ADN , Células HeLa , Humanos , Lípidos , Ratones , Sondas Moleculares/ultraestructura , Células 3T3 NIH/ultraestructura , Tamaño de la Partícula , Proteínas , Puntos Cuánticos/ultraestructura , ARN , Óxido de Zinc/químicaRESUMEN
Current cancer diagnosis employs various nuclear morphometric measures. While these have allowed accurate late-stage prognosis, early diagnosis is still a major challenge. Recent evidence highlights the importance of alterations in mechanical properties of single cells and their nuclei as critical drivers for the onset of cancer. We here present a method to detect subtle changes in nuclear morphometrics at single-cell resolution by combining fluorescence imaging and deep learning. This assay includes a convolutional neural net pipeline and allows us to discriminate between normal and human breast cancer cell lines (fibrocystic and metastatic states) as well as normal and cancer cells in tissue slices with high accuracy. Further, we establish the sensitivity of our pipeline by detecting subtle alterations in normal cells when subjected to small mechano-chemical perturbations that mimic tumor microenvironments. In addition, our assay provides interpretable features that could aid pathological inspections. This pipeline opens new avenues for early disease diagnostics and drug discovery.
Asunto(s)
Núcleo Celular/ultraestructura , Aprendizaje Profundo , Neoplasias/diagnóstico , Biomarcadores de Tumor , Línea Celular Tumoral/ultraestructura , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Neoplasias/diagnóstico por imagen , Neoplasias/ultraestructura , Redes Neurales de la Computación , Imagen Óptica/métodosRESUMEN
Specific antitumor immunotherapy with autologous dendritic cell vaccines is one of the new approaches of modern medicine. For activation of dendritic cells highly immunogenic antigens are used, however optimal antigens in case of bladder cancer (BC) are still not researched. Cancer-testis antigens (CTA) are the most promising target in the context of creation of antitumor vaccines, because they are distinguished by pronounced immunogenicity, they are detected in different types of tumors and have limited pattern of expression in healthy tissues of grown-up organism. Regarding the level of mutational load, bladder cancer (BC) holds the third position among all malignant growths, which creates particular opportunities for use of immunotherapy in case of this disease. At chromosomal level most times the following cytogenetic anomalies specific for BC are detected: hyperploidies at 3, 7 and 17 chromosomes and deletion of 9p 21 locus. Besides, in the literature there is information about possible monosomy at 2, 3, 6, 8, 13, 14, 17 and frequent loss of Y chromosome in case of BC. Development of personified dendritic cell antitumor vaccines (PDAV) against bladder cancer (BC) is a relevant problem, which covers many aspects, necessary for its standardization. In particular, in case of cultivation of tumor cells under in vitro conditions their transformation goes at higher pace in comparison with in vivo tumor development. Moreover, the article presents the results of the study of molecular-genetic features of BC of tumor cultures in case of long-term cultivation, the level of expression of CTA (MAGE, NY-ESO-1, GAGE, BAGE) by urothelial carcinoma cells (UCC). There has been described the karyotypes of cells of urothelial low differentiated carcinoma of high malignant potential at various passages with prolonged cultivation, as well as the correlation between cytogenetic profile and expression of tumor-specific cancer-testis antigens has been identified. There have been developed two verified cell line cultures of muscle invasive and muscle-non-invasive urothelial carcinoma, that are potentially useful for the producing of tumor-associated vaccines against BC.
Asunto(s)
Carcinoma de Células Transicionales/patología , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/patología , Adulto , Anciano , Anciano de 80 o más Años , Antígenos de Neoplasias/metabolismo , Vacunas contra el Cáncer , Carcinoma de Células Transicionales/inmunología , Carcinoma de Células Transicionales/terapia , Técnicas de Cultivo de Célula/métodos , Línea Celular Tumoral/metabolismo , Línea Celular Tumoral/ultraestructura , Aberraciones Cromosómicas , Criopreservación , Humanos , Persona de Mediana Edad , Células Tumorales Cultivadas/metabolismo , Células Tumorales Cultivadas/ultraestructura , Neoplasias de la Vejiga Urinaria/inmunología , Neoplasias de la Vejiga Urinaria/terapia , Urotelio/patologíaRESUMEN
Breast cancer (BC) is the most common cause of cancer-related death worldwide. Although platinum-based drugs (PBDs) are effective anticancer agents, responsive patients eventually become resistant. While resistance of some cancers to PBDs has been explored, the cellular responses of BC cells are not studied yet. Therefore, we aim to assess the differential effects of PBDs on BC ultrastructure. Three representative cells were treated with different concentrations and timing of Cisplatin, Carboplatin, and Oxaliplatin. Changes on cell surface and ultrastructure were detected by scanning (SEM) and transmission electron microscope (TEM). In SEM, control cells were semiflattened containing microvilli with extending lamellipodia while treated ones were round with irregular surface and several pores, indicating drug entry. Prolonged treatment resembled distinct apoptotic features such as shrinkage, membrane blebs, and narrowing of lamellipodia with blunt microvilli. TEM detected PBDs' deposits that scattered among cellular organelles inducing structural distortion, lumen swelling, chromatin condensation, and nuclear fragmentation. Deposits were attracted to fat droplets, explained by drug hydrophobic properties, while later they were located close to cell membrane, suggesting drug efflux. Phagosomes with destructed organelles and deposits were detected as defending mechanism. Understanding BC cells response to PBDs might provide new insight for an effective treatment.
Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Línea Celular Tumoral/efectos de los fármacos , Resistencia a Antineoplásicos/efectos de los fármacos , Fagosomas/efectos de los fármacos , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Carboplatino/administración & dosificación , Línea Celular Tumoral/ultraestructura , Cisplatino/administración & dosificación , Femenino , Humanos , Microscopía Electrónica de Transmisión , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Fagosomas/ultraestructuraRESUMEN
We present liquid-cell transmission electron microscopy (liquid-cell TEM) imaging of fixed and non-fixed prostate cancer cells (PC3 and LNCaP) with high resolution in a custom developed silicon nitride liquid cell. Fixed PC3 cells were imaged for 90-120 min without any discernable damage. High contrast on the cellular structures was obtained even at low electron doses (~2.5 e-/nm2 per image). The images show distinct structures of cell compartments (nuclei and nucleoli) and cell boundaries without any further sample embedding, dehydration, or staining. Furthermore, we observed dynamics of vesicles trafficking from the cell membrane in consecutive still frames in a non-fixed cell. Our findings show that liquid-cell TEM, operated at low electron dose, is an excellent tool to investigate dynamic events in non-fixed cells with enough spatial resolution (few nm) and natural amplitude contrast to follow key intracellular processes.
Asunto(s)
Microfluídica/métodos , Microscopía Electrónica de Transmisión/métodos , Nanopartículas/química , Antígenos de Superficie , Técnicas de Cultivo de Célula , Línea Celular Tumoral/ultraestructura , Electrones , Glutamato Carboxipeptidasa II , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Microtecnología/métodos , Neoplasias de la Próstata , Compuestos de Silicona , Coloración y EtiquetadoRESUMEN
An inherent dilemma in the use of nanomedicines for cancer drug delivery is their limited penetration into tumors due to their large size. We have demonstrated that dendrimer/lipid nanoassemblies can solve this problem by means of tumor-triggered disassembly and the release of small (several nanometers) dendrimers to facilitate tumor penetration. Herein, we report a general strategy for the fabrication of nanoassemblies from hydrophobic and hydrophilic dendrimers with phospholipids. Hydrophobic dendrimers could assemble with lipids via hydrophobic interactions, whereas hydrophilic dendrimers could only assemble with lipids in the presence of anionic surfactants via both electrostatic and hydrophobic interactions. The nanoassemblies of hydrophobic dendrimers/lipids were found to be capable of stripping off their lipid layers via fusion with the cell membrane and then intracellular or extracellular release of dendrimers, whereas the nanoassemblies of hydrophilic dendrimers/lipids were internalized via endocytosis and then released their dendrimers inside the cells. Therefore, these dendrimer/lipid nanoassemblies could be used for the delivery of different cancer drugs.
Asunto(s)
Dendrímeros/química , Sistemas de Liberación de Medicamentos , Membrana Dobles de Lípidos/química , Antineoplásicos/química , Antineoplásicos/metabolismo , Línea Celular Tumoral/citología , Línea Celular Tumoral/metabolismo , Línea Celular Tumoral/ultraestructura , Dendrímeros/metabolismo , Femenino , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Nanomedicina , Neoplasias Ováricas , Poliaminas/química , Electricidad EstáticaRESUMEN
A novel pyridyl functionalized analog of the promising hexadentate 68Ga3+ chelate H2dedpa (N4O2, 1,2-[[6-carboxy-pyridin-2-yl]-methylamine]ethane) was successfully synthesized and characterized. This new bifunctional chelate (BFC) was used to prepare the first proof-of-principle bi-modal H2dedpa derivative for fluorescence and nuclear imaging. Two bi-modal H2dedpa derivatives were prepared: H2dedpa-propylpyr-FITC and H2dedpa-propylpyr-FITC-(N,N'-propyl-2-NI) (FITC=fluorescein, pyr=pyridyl functionalized, NI=nitroimidazole). The ligands possess the strong gallium-coordinating atoms contained within dedpa2- that are ideal for radiolabeling with 68Ga3+ for positron-emission tomography (PET) imaging, and two fluorophores for optical imaging. In addition, one analog contains two NI moieties for specific entrapment of the tracer in hypoxic cells. These new bi-modal analogs were compared to the native unfunctionalized H2dedpa scaffold to determine the extent to which the addition of pyridyl functionalization would affect metal coordination, and complex stability. The non-radioactive gallium complexes were tested in a 3D tumor spheroid model. The novel pyridyl bis-functionalized H2dedpa ligand, H2dedpa-propylpyr-NH2, was quantitatively radiolabeled with 67Ga (RCY>99%) under reaction conditions commensurate with unfunctionalized H2dedpa (10min at room temperature) at ligand concentrations as low as 10-5M. The resultant 67Ga-complex withstood transchelation to the in vivo metal-binding competitor apo-transferrin (2h at 37°C, 93% intact), signifying that [Ga(dedpa-propylpyr-NH2)]+ is a kinetically inert complex suitable for in vivo use, but exhibited slightly reduced stability compared to the native [67Ga(dedpa)] scaffold (>99% intact). Finally, bi-model fluorescent Ga-dedpa compounds were successfully imaged in a 3D tumor spheroid model. The Ga-dedpa-FITC-NI derivative was specifically localized in the central hypoxic core of the spheroid.
Asunto(s)
Quelantes/síntesis química , Complejos de Coordinación/síntesis química , Etilaminas/síntesis química , Radioisótopos de Galio/química , Piridinas/síntesis química , Radiofármacos/síntesis química , Apoproteínas/química , Hipoxia de la Célula , Línea Celular Tumoral/efectos de los fármacos , Línea Celular Tumoral/metabolismo , Línea Celular Tumoral/ultraestructura , Quelantes/farmacocinética , Colon/efectos de los fármacos , Colon/metabolismo , Colon/ultraestructura , Complejos de Coordinación/farmacocinética , Estabilidad de Medicamentos , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Células Epiteliales/ultraestructura , Etilaminas/farmacocinética , Fluoresceína-5-Isotiocianato/química , Humanos , Nitroimidazoles/química , Imagen Óptica/métodos , Tomografía de Emisión de Positrones/métodos , Piridinas/farmacocinética , Radiofármacos/farmacocinética , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/metabolismo , Esferoides Celulares/ultraestructura , Transferrina/químicaRESUMEN
Rare-earth (RE) doped nanocomposites emit visible luminescence when illuminated with continuous wave near-infrared light, making them appealing candidates for use as contrast agents in biomedical imaging. However, the emission lifetime of these materials is much longer than the pixel dwell times used in scanning intravital microscopy. To overcome this limitation, we have developed a line-scanning confocal microscope for high-resolution, optically sectioned imaging of samples labeled with RE-based nanomaterials. Instrument performance is quantified using calibrated test objects. NaYF4 : Er,Yb nanocomposites are imaged in vitro, and in ex vivo tissue specimens, with direct comparison to point-scanning confocal microscopy. We demonstrate that the extended pixel dwell time of line-scanning confocal microscopy enables subcellular-level imaging of these nanomaterials while maintaining optical sectioning. The line-scanning approach thus enables microscopic imaging of this emerging class of contrast agents for preclinical studies, with the potential to be adapted for real-time in vivo imaging in the clinic.
Asunto(s)
Línea Celular Tumoral/química , Aumento de la Imagen/instrumentación , Microscopía Fluorescente/instrumentación , Imagen Molecular/métodos , Nanopartículas/química , Nanopartículas/ultraestructura , Línea Celular Tumoral/ultraestructura , Medios de Contraste/química , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Metales de Tierras Raras , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
We describe two-step fluorescence microscopy, a new approach to non-linear imaging based on positive reversible photoswitchable fluorescent probes. The protein Padron approximates ideal two-step fluorescent behaviour: it equilibrates to an inactive state, converts to an active state under blue light, and blue light also excites this active state to fluoresce. Both activation and excitation are linear processes, but the total fluorescent signal is quadratic, proportional to the square of the illumination dose. Here, we use Padron's quadratic non-linearity to demonstrate the principle of two-step microscopy, similar in principle to two-photon microscopy but with orders-of-magnitude better cross-section. As with two-photon, quadratic non-linearity from two-step fluorescence improves resolution and reduces unwanted out-of-focus excitation, and is compatible with structured illumination microscopy. We also show two-step and two-photon imaging can be combined to give quartic non-linearity, further improving imaging in challenging samples. With further improvements, two-step fluorophores could replace conventional fluorophores for many imaging applications.
Asunto(s)
Colorantes Fluorescentes , Microscopía Fluorescente/métodos , Línea Celular Tumoral/ultraestructura , Humanos , Dinámicas no LinealesRESUMEN
The microscope image of a thick fluorescent sample taken at a given focal plane is plagued by out-of-focus fluorescence and diffraction limited resolution. In this work, we show that a single slice of Structured Illumination Microscopy (two or three beam SIM) data can be processed to provide an image exhibiting tight sectioning and high transverse resolution. Our reconstruction algorithm is adapted from the blind-SIM technique which requires very little knowledge of the illumination patterns. It is thus able to deal with illumination distortions induced by the sample or illumination optics. We named this new algorithm thick slice blind-SIM because it models a three-dimensional sample even though only a single two-dimensional plane of focus was measured.
Asunto(s)
Microscopía Fluorescente/métodos , Imagen Óptica/métodos , Actinas/análisis , Algoritmos , Artefactos , Neoplasias de la Mama/patología , Línea Celular Tumoral/ultraestructura , Femenino , Humanos , Iluminación , Microscopía Fluorescente/instrumentación , Paxillin/análisisRESUMEN
A gemcitabine (GEM)-resistant human pancreatic cancer cell line (PANC-1RG7) was established in vitro by gradually increasing GEM concentrations and cloning cell cultures to develop a cellular model of acquired drug resistance studies. We found that PANC-1RG7 cells exhibited significantly different morphological characteristics from parental cells. PANC-1RG7 cells grew slowly (p<0.05), yet the cell cycle remained unchanged (p>0.05). PANC-1RG7, with a resistance index to GEM of 39.9, showed cross-resistance characteristics to methotrexate, gefitinib, cisplatin and 5-fluorouracil. The proliferation inhibition of GEM was significantly reduced in vivo (p<0.05). The known resistance-associated genes and proteins we detected remained unchanged, with the exception of cytidine deaminase, multidrug resistance-related protein and breast cancer resistance protein genes, which decreased; by contrast, 5'-nucleotidase, ribonucleotide reductase (RRM) 1 and RRM2 proteins increased (p<0.05). Therefore, a cell line with acquired GEM resistance was established successfully. Resistance was acquired by overexpressing RRM1 and RRM2 proteins.
Asunto(s)
Desoxicitidina/análogos & derivados , Resistencia a Antineoplásicos/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Ribonucleótido Reductasas/metabolismo , Animales , Antimetabolitos Antineoplásicos/farmacología , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Línea Celular Tumoral/ultraestructura , Cisplatino/farmacología , Desoxicitidina/farmacología , Fluorouracilo/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones Desnudos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Ribonucleósido Difosfato Reductasa/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , GemcitabinaRESUMEN
BACKGROUND: Selol is an oily mixture of selenitetriacylglycerides that was obtained as a semi-synthetic compound containing selenite. Selol is effective against cancerous cells and less toxic to normal cells compared with inorganic forms of selenite. However, Selol's hydrophobicity hinders its administration in vivo. Therefore, the present study aimed to produce a formulation of Selol nanocapsules (SPN) and to test its effectiveness against pulmonary adenocarcinoma cells (A549). RESULTS: Nanocapsules were produced through an interfacial nanoprecipitation method. The polymer shell was composed of poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA) copolymer. The obtained nanocapsules were monodisperse and stable. Both free Selol (S) and SPN reduced the viability of A549 cells, whereas S induced a greater reduction in non-tumor cell viability than SPN. The suppressor effect of SPN was primarily associated to the G2/M arrest of the cell cycle, as was corroborated by the down-regulations of the CCNB1 and CDC25C genes. Apoptosis and necrosis were induced by Selol in a discrete percentage of A549 cells. SPN also increased the production of reactive oxygen species, leading to oxidative cellular damage and to the overexpression of the GPX1, CYP1A1, BAX and BCL2 genes. CONCLUSIONS: This study presents a stable formulation of PVM/MA-shelled Selol nanocapsules and provides the first demonstration that Selol promotes G2/M arrest in cancerous cells.
Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Puntos de Control del Ciclo Celular/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Maleatos/química , Nanocápsulas/química , Polietilenos/química , Compuestos de Selenio/farmacología , Adenocarcinoma/patología , Adenocarcinoma/ultraestructura , Adenocarcinoma del Pulmón , Antineoplásicos/administración & dosificación , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Línea Celular Tumoral/ultraestructura , Ciclina B1/genética , Relación Dosis-Respuesta a Droga , Glutatión Peroxidasa/genética , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/ultraestructura , Nanocáscaras/química , Especies Reactivas de Oxígeno/metabolismo , Compuestos de Selenio/administración & dosificación , Compuestos de Selenio/química , Termodinámica , Fosfatasas cdc25/genética , Glutatión Peroxidasa GPX1RESUMEN
Cystoisospora belli is an opportunistic protozoan that causes human cystoisosporiasis, an infection characterized by diarrhea, steatorrhea, abdominal pain, fever, and weight loss. The lack of animal models susceptible to C. belli, and the difficulty in obtaining clinical samples with fair amounts of oocysts have limited the research pertaining to the basic biology of this parasite. This study aimed to describe the ultrastructure of endogenous stages of C. belli in Monkey Rhesus Kidney Cells (MK2) and Human Ileocecal Adenocarcinoma cells (HCT-8). Zoites of C. belli exhibited typical morphological features of coccidia, which included a trilaminar pellicle, an apical complex formed by a conoid, polar rings, rhoptries, and micronemes, in addition to dense granules and the endoplasmic reticulum. No crystalloid body was observed but various lipid and amylopectin granules were usually present in the cytoplasm of zoites. We observed a tendency of the endoplasmic reticulum of the host cell to be located near the parasitophorous vacuole membrane. Merozoites were formed by endodyogeny and during replication, the apical complex of the mother cell remained intact. The formation of gametes or oocysts was not observed. The ultrastructural findings of C. belli are further evidence of its proximity to Sarcocystidae family members and corroborate their reclassification as Cystoisospora spp.
Asunto(s)
Isospora/ultraestructura , Animales , Línea Celular/parasitología , Línea Celular/ultraestructura , Línea Celular Tumoral/parasitología , Línea Celular Tumoral/ultraestructura , Humanos , Riñón/citología , Riñón/parasitología , Macaca mulatta , Merozoítos/ultraestructura , Microscopía Electrónica de TransmisiónRESUMEN
OBJECTIVES: The objectives of this study were to test the effects of the new combination treatment modality, sorafenib (SOR) and lithium chloride (LiCl) and to assess whether midkine (MK) protein has a role in any potential effects. METHODS: Monolayer and spheroid cultures of T98G human glioblastoma multiforme (GBM) cells were treated with LiCl and SOR (inhibition concentration 50 value â=â 100 µM), or their combination, or were left untreated (control). Cell proliferation and apoptotic indices, the mechanism of action, and the levels of apoptotic and anti-apoptotic proteins were evaluated in monolayer cultures and ultrastructure was evaluated by transmission electron microscopy (TEM) in spheroid cultures after for 72 hours. RESULTS: All drug applications decreased cell numbers and increased the apoptotic index. The combination shows a synergistic effect. In the combination group, the decrease in cell numbers and the increase in the apoptotic index were significantly greater than with the individual drugs (P < 0.01). The combination treatment led to the greatest decreases in MRP-1 and p170 levels; but the greatest decreases in p-STAT-3, p-ERK (P < 0.05), p-AKT, p-GSK-3-beta (P < 0.01), EGFR (P < 0.01), NF-kappa-ß levels were with SOR alone, followed by the combination. The decreases in MK levels in the SOR and combination groups were similar (P â=â 0.06). Severe ultrastructural damage was more frequently observed in the combination group compared with the other groups. CONCLUSIONS: These results suggest the possibility that the addition of LiCl to SOR could improve the prognosis in at least some patients who need both cancer and psychotherapy and indicate the need for further studies.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Citocinas/metabolismo , Glioblastoma/tratamiento farmacológico , Cloruro de Litio/uso terapéutico , Niacinamida/análogos & derivados , Compuestos de Fenilurea/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral/ultraestructura , Proliferación Celular/efectos de los fármacos , Receptores ErbB/metabolismo , Glioblastoma/ultraestructura , Humanos , Midkina , Niacinamida/uso terapéutico , SorafenibRESUMEN
A Pt (IV) complex which combined the bioactivities of both oxaliplatin and demethylcantharidin (DMC) is synthesized and delivered by a polymer-drug conjugate for combination chemotherapy. Oxaliplatin is released from the polymer-drug conjugate within cancer cell by reduction to attack nuclear DNA, while a dose of DMC is also hydrolyzed subsequently to block DNA damage-induced defense mechanisms by serine/threonine phosphatase 2A (PP2A) inhibition. In vitro evaluation shows that the polymer-drug conjugate with dual modes of action upon cancer cells displays higher cytotoxicity against SKOV-3 cells than that of free drugs. This enhanced cytotoxicity is attributed to the synergistic effect between oxaliplatin and DMC, as well as the effective intracellular internalization of the micelles observed by confocal laser scanning microscopy (CLSM) imaging.
Asunto(s)
Cantaridina/análogos & derivados , Neoplasias/tratamiento farmacológico , Compuestos Organoplatinos/administración & dosificación , Polímeros/administración & dosificación , Cantaridina/administración & dosificación , Cantaridina/química , Línea Celular Tumoral/efectos de los fármacos , Línea Celular Tumoral/ultraestructura , Humanos , Micelas , Microscopía Confocal , Neoplasias/patología , Compuestos Organoplatinos/química , Oxaliplatino , Polímeros/químicaRESUMEN
2,2',4,4'-tetrabromodiphenyl ether (PBDE-47)-elicited neurotoxicity is associated with neural apoptosis; however the underlying mechanisms remain unclear. To investigate whether the mitochondrial p53 pathway is involved in neuronal apoptosis induced by PBDE-47 and to correlate DNA hypomethylation with p53 activation, human neuroblastoma (SH-SY5Y) cells were treated with different concentrations of PBDE-47 (1, 5, 10 µmol/L) for 24h in vitro. The apoptosis and ultrastructural alterations in cells, levels of p53, Bcl-2, Bax, cytochrome c (Cyt c), caspase-3 and methylation status of p53 promoter were determined. Hoechst 33258 staining and transmission electron microscopy analysis showed that PBDE-47 induced SH-SY5Y cells apoptosis characterized by the typical apoptotic morphological changes. In addition, PBDE-47 activated the p53-dependent mitochondrial apoptotic pathway as evidenced by up-regulation of p53 and Bax, down-regulation of Bcl-2 and Bcl-2/Bax ration, enhancement of Cyt c release from mitochondria into the cytosol, activation of caspase-3 as well as ultrastructural abnormalities of mitochondria. However, no obvious decrease in p53 promoter methylation levels was observed in any of the treatment groups by bisulfite genomic sequencing. Collectively, these results suggest that the mitochondrial p53 pathway is involved in PBDE-47-induced SH-SY5Y cells apoptosis, nevertheless p53 promoter hypomethylation may not be implicated in this process.