Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 20
Filtrar
Más filtros












Base de datos
Intervalo de año de publicación
1.
Ultrastruct Pathol ; 46(5): 413-438, 2022 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-36165802

RESUMEN

Human prostate carcinoma DU145 cells, androgen-independent malignant cells, implanted in the athymic nu/nu male mouse, developed numerous tumors on peritoneal and retro-peritoneal organs whose growth aspects and vascular supply have yet to be investigated with fine structure techniques. A series of necropsies from moribund implanted mice diaphragms were examined with light, scanning, and transmission electron microscopy. DU145 xenografts installations, far away from the implanted site, were described as the smallest installation to large diaphragm outgrowths in moribund mice. Carcinomas did not show extracellular matrix and, reaching more than 0.15 mm in thickness, they revealed new structures in these outgrowths. Voids to be gland-like structures with mediocre secretion and, unexpectedly, intercellular spaces connected with fascicles of elongated DU145 cells that merged with a vascular supply originated from either the tumor cells and/or some perimysium vessels. In the largest carcinomas, most important vascular invasions coincidently accompanied the mouse lethality, similarly to human cancers. This androgen-independent model would be useful to study tumor outgrowth's changes related to testing anticancer strategy, including anti-angiogenic therapies involving toxicity, simultaneously with those of other vital organs with combined biomolecular and fine structure techniques.


Asunto(s)
Carcinoma , Neoplasias de la Próstata , Andrógenos , Animales , Línea Celular Tumoral , Diafragma/patología , Epitelio/patología , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , Próstata/patología , Neoplasias de la Próstata/patología
2.
Ultrastruct Pathol ; 40(5): 231-9, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27163289

RESUMEN

Ultrastructural data compiled from DU145 human prostate carcinoma cells growing in vivo and, more often in vitro or after treatment by pro-oxidant reactants, can induce and encompass several processes of cell internalization or entosis. These events were observed after tumor cells were essentially undergoing autoschizic injuries and other cell deaths without externalization of phosphatidylserine. Based on other previous observations made on DU145 cells, one hypothesizes that, as a means of survival, tumor cells find sources of nutrients through phagocytosis of apparently intact, injured cells, corpses, and cell debris by cannibalism. These peculiar activities occurred sporadically, in a small population of cells and could be dictated by their widely adapted energetic metabolism, now impaired, either due to the location of the cells in the growing tumors or in vitro as a result of this pro-oxidant anticancer treatment causing damage and abolishing their adapted metabolism.


Asunto(s)
Entosis/fisiología , Neoplasias de la Próstata/patología , Animales , Línea Celular Tumoral , Xenoinjertos , Humanos , Masculino , Ratones , Microscopía Electrónica de Transmisión
3.
Ultrastruct Pathol ; 40(4): 189-99, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27044781

RESUMEN

The intracellular or intracytoplasmic lumen (IL) is an enigmatic histological structure that occurs in various tumor cells. A reassessment of diverse ILs fine-structure micrographs obtained out of previous studies encompassing the human prostate carcinoma (DU145) cell line and xenotransplanted carcinomas enabled us to propose aspects of ILs development in cancer cells: a combination of altered expressions in intercellular contacts and their cytoskeletal components would favor a disarray of self-apical polarity orientation; those defects, associated with a local, entwined enriched membranous structures growing as microvilli-like formations out of a disrupted endoplasm and trans-Golgi sorting, create ILs in cells' perikarya. These misplaced intracytoplasmic domains can become enlarged through spaces made between the finger-like structures by accruing membranes of coalescent intracytoplasmic vesicles then adding microvilli and glycocalyx to constitute ILs. Cationic mucins added with or without a progressive or total loss of microvilli and content generate signet or ring cell, while ILs enlarge. Variable build-ups of these cells' populations in carcinomas result in architectural mix-up of adjacent cells around these voids, misconstrued as new lumen, and establish a "cribriform" tumor pattern that often implies a poor cancer prognosis. Alternatively, cytotoxic changes caused by anticancer pro-oxidant treatment favor membrane alterations and exaggerate the ILs in xenotransplants into intracellular crypts that accompany other tumor degenerative changes.


Asunto(s)
Carcinoma/patología , Carcinoma/ultraestructura , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/ultraestructura , Animales , Diferenciación Celular , Línea Celular Tumoral , Xenoinjertos , Humanos , Masculino , Ratones , Ratones Desnudos , Microscopía Electrónica de Transmisión
4.
Ultrastruct Pathol ; 38(5): 315-28, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24955925

RESUMEN

One hour after pro-oxidative treatment by either ascorbate (VC), menadione (VK3), or VC: VK3 combination followed by 24-h incubation in culture medium, DU145 human prostate carcinoma cells developed ultrastructural-dependent organelle damage with the sequence Sham > VC > VK3 > VC: VK3. Along the nuclear alterations and the cytoplasm self-excisions reducing cell size, other induced injuries concerned mitochondria and endomembranes that associated with lysosomes. Damaged organelles surrounded by specialized endoplasmic membranes formed autophagosomes out of phagophores that also captured pieces of glycogen-rich cytoplasm. Most autophagosomes amassed in the diminished-size perikarya and corroborated the enhanced cytotoxicity of the VC: VK3 treatment. These accumulations did not initiate cell death, instead were merely signs of excessive "recycling" of damaged organelles. These features may reflect that high lysosomal activities provided foodstuffs in an ultimate strategy of survival of the tumor cells already devastated by reactive oxidative species (ROS) energetic sites. As such they became transient markers preceding cell death induced to occur by autoschizis and not by apoptosis or other cell deaths. This report could provide more support for the usage of this vitamin combination named APATONE as inexpensive potent adjuvant or treatment in prostate cancers.


Asunto(s)
Autofagia , Citoplasma/ultraestructura , Mitocondrias/ultraestructura , Neoplasias de la Próstata/patología , Muerte Celular , Línea Celular Tumoral , Humanos , Lisosomas/patología , Masculino , Neoplasias de la Próstata/metabolismo , Especies Reactivas de Oxígeno/farmacología , Vitamina K 3/metabolismo
5.
Ultrastruct Pathol ; 38(2): 116-40, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24460713

RESUMEN

Scanning (SEM) and transmission electron microscopy (TEM) were used to characterize the cytotoxic effects of ascorbate (VC), menadione (VK3), or a VC:VK3 combination on a human prostate carcinoma cell line (DU145) following a 1-h vitamin treatment and a subsequent 24-h incubation in culture medium. Cell alterations examined by light and electron microscopy were treatment-dependent with VC + VK3 >VK3 > VC > Sham. Oxidative stress-induced damage was found in most organelles. This report describes injuries in the tumor cell nucleus (chromatin and nucleolus), mitochondria, endomembranes, lysosomal bodies (autophagocytoses) and inclusions. Morphologic alterations suggest that cytoskeleton damage is likely responsible for the superficial cytoplasmic changes, including major changes in cell shape and size and the self-excising phenomena. Unlike apoptotic bodies, the excised pieces contain ribonucleoproteins, but not organelles. These deleterious events cause a progressive, significant reduction in the tumor cell size. During nuclear alterations, the nuclei maintain their envelope during chromatolysis and karyolysis until cell death, while nucleoli undergo a characteristic segregation of their components. In addition, changes in fat and glycogen storage are consistent the cytotoxic and metabolic alterations caused by the respective treatments. All cellular ultrastructural changes are consistent with cell death by autoschizis and not apoptosis or other kinds of cell death.


Asunto(s)
Adenocarcinoma/ultraestructura , Ácido Ascórbico/farmacología , Muerte Celular/efectos de los fármacos , Neoplasias de la Próstata/ultraestructura , Vitamina K 3/farmacología , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/ultraestructura , Citoesqueleto/efectos de los fármacos , Citoesqueleto/ultraestructura , Humanos , Masculino , Microscopía Electrónica , Orgánulos/efectos de los fármacos , Orgánulos/ultraestructura
6.
Ultrastruct Pathol ; 37(6): 440-8, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23957452

RESUMEN

DU145 human prostate carcinoma cells are typically poorly differentiated and contain only scantily distributed organelles. However, among numerous tumor cells randomly examined by electron microscopy out of in vitro cultivation, a peculiar, rare oncocyte-like cell type has been observed whose nucleus appears to be of small dimension and with a cytoplasm almost entirely filled with often distorted mitochondria. A few small, dispersed lysosomal bodies, small cisterns of the endoplasmic reticulum and a few glycogen patches can be found among highly osmiophilic contrasted, cytosolic spaces filled by innumerable ribonucleoproteins. The excessive population of mitochondria may have arisen from a more populated tumor cell type wherein the altered mitochondria are found to appear burgeoning into a spherical-like size progeny crowding the tumor cells. Literature cited between 1950 and the present suggests that this rare, oncocytic, benign prostatic tumor cell type is likely appear epigenetically, stemming from an original secretory cell, which is confirmed by the origin of the cell line originally maintained as cell line out of a brain metastatic, adenocarcinoma niche.


Asunto(s)
Adenocarcinoma/ultraestructura , Neoplasias Encefálicas/ultraestructura , Células Oxífilas/ultraestructura , Neoplasias de la Próstata/ultraestructura , Adenocarcinoma/química , Adenocarcinoma/secundario , Neoplasias Encefálicas/química , Neoplasias Encefálicas/secundario , Línea Celular Tumoral , Forma del Núcleo Celular , Tamaño de la Célula , Glucógeno/análisis , Humanos , Masculino , Microscopía Electrónica de Transmisión , Mitocondrias/ultraestructura , Células Oxífilas/química , Neoplasias de la Próstata/química , Ribonucleoproteínas/análisis
7.
Anat Rec (Hoboken) ; 296(1): 40-55, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23109249

RESUMEN

Implanted human, androgen-independent prostatic carcinoma cells (DU145) into athymic (NCr nu/nu) mice produce diverse tumors on the peritoneal surfaces of many organs. Light and ultrastructural observations show that the mesothelial covering these surfaces are typically microvilli-coated, squamous cells or secretory cuboidal cells. The peritoneal regions colonized by tumors lack mesothelial cells and are covered by actively replicating carcinoma cells that grow as poorly differentiated cell clusters made of cell aggregates to somewhat compact spheroids covered with pleiomorphic microvilli and containing an undifferentiated vascular supply. These xenografts clusters invade the diaphragm and develop into tumors with both a basal solid aspect and an upper region of cribriform morphology. Furthermore, each tumor contains two cell types: (1) a poorly differentiated clear cell type, which grows into intraperitoneal tumors and (2) a large, basophilic cell type, which invades the peritoneal stroma of organs, including of the diaphragm.


Asunto(s)
Proliferación Celular , Peritoneo/patología , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/fisiopatología , Animales , Línea Celular Tumoral , Epitelio/patología , Epitelio/fisiopatología , Epitelio/ultraestructura , Humanos , Masculino , Ratones , Ratones Desnudos , Microvellosidades/patología , Microvellosidades/ultraestructura , Invasividad Neoplásica/patología , Invasividad Neoplásica/fisiopatología , Invasividad Neoplásica/ultraestructura , Neoplasias Peritoneales/fisiopatología , Neoplasias Peritoneales/secundario , Neoplasias Peritoneales/ultraestructura , Peritoneo/fisiopatología , Peritoneo/ultraestructura , Neoplasias de la Próstata/ultraestructura , Trasplante Heterólogo
8.
Ultrastruct Pathol ; 36(5): 294-311, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23025648

RESUMEN

Androgen-independent, human prostate carcinoma cells (DU145) develop into solid, carcinomatous xenotransplants on the diaphragm of nu/nu mice. Tumors encompass at least two poorly differentiated cell types: a rapidly dividing, eosinophilic cell comprises the main cell population and a few, but large basophilic cells able to invade the peritoneal stroma, the muscular tissue, lymph vessels. Poor cell contacts, intracytoplasmic lumina, and signet cells are noted. Lysosomal activities are reflected by entoses and programmed cell deaths forming cribriform carcinomas. In large tumors, degraded cells may align with others to facilitate formation of blood supply routes. Malignant cells would spread via ascites and through lymphatics.


Asunto(s)
Adenocarcinoma/ultraestructura , Carcinoma/ultraestructura , Neoplasias de la Próstata/ultraestructura , Adenocarcinoma/irrigación sanguínea , Animales , Apoptosis , Basófilos/ultraestructura , Carcinoma/irrigación sanguínea , Diferenciación Celular , Línea Celular Tumoral , Proliferación Celular , Entosis , Humanos , Vasos Linfáticos/ultraestructura , Lisosomas/ultraestructura , Masculino , Ratones , Ratones Desnudos , Microscopía Electrónica de Transmisión , Invasividad Neoplásica , Trasplante de Neoplasias , Fenotipo , Neoplasias de la Próstata/irrigación sanguínea , Células del Estroma/ultraestructura , Trasplante Heterólogo
9.
Ultrastruct Pathol ; 34(3): 140-60, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20455663

RESUMEN

A human bladder carcinoma cell line RT4 was sham-treated with buffer or treated with ascorbate (VC) alone, menadione alone (VK(3)), or a combination of ascorbate:menadione (VC+VK(3)) for 1, 2, and 4 h. Cytotoxic damage was found to be treatment-dependent in this sequence: VC+VK(3)>VC>VK(3)>sham. The combined treatment induced the greatest oxidative stress, with early tumor cell injury affecting the cytoskeletal architecture and contributing to the self-excisions of pieces of cytoplasm freed from organelles. Additional damage, including a reduction in cell size, organelle alterations, nuclear damage, and nucleic acid degradation as well as compromised lysosome integrity, is caused by reactivation of DNases and the redox cycling of VC or VC+VK(3). In addition, cell death caused by VC+VK(3) treatment as well as by prolonged VC treatment is consistent with cell demise by autoschizis, not apoptosis. This report confirms and complements previous observations about this new mode of tumor cell death. It supports the contention that a combination of VC+VK(3), also named Apatone, could be co-administered as a nontoxic adjuvant with radiation and/or chemotherapies to kill bladder tumor cells and other cancer cells without any supplementary risk or side effects for patients.


Asunto(s)
Antineoplásicos/farmacología , Ácido Ascórbico/farmacología , Muerte Celular/efectos de los fármacos , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Vitamina K 3/farmacología , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/ultraestructura , Supervivencia Celular/efectos de los fármacos , Daño del ADN , Ensayos de Selección de Medicamentos Antitumorales , Quimioterapia Combinada , Humanos , Masculino , Microscopía Electrónica de Transmisión , Orgánulos/efectos de los fármacos , Orgánulos/ultraestructura , Estrés Oxidativo/efectos de los fármacos , Neoplasias de la Vejiga Urinaria/metabolismo , Neoplasias de la Vejiga Urinaria/patología
10.
J Histochem Cytochem ; 58(7): 635-51, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20385787

RESUMEN

Ascorbate and menadione (Apatone) in a ratio of 100:1 kills tumor cells by autoschizis. In this study, vitamin-induced changes in nucleolar structure were evaluated as markers of autoschizis. Human bladder carcinoma (T24) cells were overlain with vitamins or with culture medium. Supernatants were removed at 1-hr intervals from 1 to 4 hr, and the cells were washed with PBS and prepared for assay. Apatone produced marked alterations in nucleolar structure including redistribution of nucleolar components, formation of ring-shaped nucleoli, condensation and increase of the proportion of perinucleolar chromatin, and the enlargement of nucleolar fibrillar centers. Immunogold labeling of the nucleolar rRNA revealed a granular localization in treated and sham-treated cells, and immunogold labeling of the rDNA revealed a shift from the fibrillar centers to the condensed perinucleolar chromatin. Fibrillarin staining shifted from the fibrillar centers and adjacent regions to a more homogeneous staining of the entire nucleolus and was consistent with the percentage of autoschizic cells detected by flow cytometry. Because autoschizis entails sequential reactivation of DNase I and DNase II, and because the fibrillarin redistribution following DNase I and Apatone treatment is identical, it appears that the nucleolar and fibrillarin changes are markers of autoschizis.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Ácido Ascórbico/farmacología , Carcinoma/ultraestructura , Nucléolo Celular/ultraestructura , Proteínas Cromosómicas no Histona/análisis , Neoplasias de la Vejiga Urinaria/ultraestructura , Vitamina K 3/farmacología , Carcinoma/química , Línea Celular Tumoral , Nucléolo Celular/química , Nucléolo Celular/efectos de los fármacos , Humanos , Neoplasias de la Vejiga Urinaria/química , Vitamina K/farmacología
11.
Int J Med Sci ; 5(2): 62-7, 2008 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-18392145

RESUMEN

PURPOSE: To evaluate the safety and efficacy of oral Apatone (Vitamin C and Vitamin K3) administration in the treatment of prostate cancer in patients who failed standard therapy. MATERIALS AND METHODS: Seventeen patients with 2 successive rises in PSA after failure of standard local therapy were treated with (5,000 mg of VC and 50 mg of VK3 each day) for a period of 12 weeks. Prostate Specific Antigen (PSA) levels, PSA velocity (PSAV) and PSA doubling times (PSADT) were calculated before and during treatment at 6 week intervals. Following the initial 12 week trial, 15 of 17 patients opted to continue treatment for an additional period ranging from 6 to 24 months. PSA values were followed for these patients. RESULTS: At the conclusion of the 12 week treatment period, PSAV decreased and PSADT increased in 13 of 17 patients (p < or = 0.05). There were no dose-limiting adverse effects. Of the 15 patients who continued on Apatone after 12 weeks, only 1 death occurred after 14 months of treatment. CONCLUSION: Apatone showed promise in delaying biochemical progression in this group of end stage prostate cancer patients.


Asunto(s)
Ácido Ascórbico/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Vitamina K 3/uso terapéutico , Administración Oral , Anciano , Ácido Ascórbico/administración & dosificación , Quimioterapia Combinada , Humanos , Masculino , Persona de Mediana Edad , Terapia Recuperativa , Vitamina K 3/administración & dosificación
12.
Anat Rec A Discov Mol Cell Evol Biol ; 288(1): 58-83, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16345077

RESUMEN

Feulgen and actin-phalloidin staining as well as gel electrophoresis have been employed in conjunction with cell ultrastructure to describe the effects of 1-, 2-, and 4-hr ascorbate (VC), menadione (VK(3)), and ascorbate:menadione (VC:VK(3)) treatments on the T24 human bladder carcinoma cell line. T24 cells exposed to VC alone display blebs and other superficial membrane defects related to membrane alterations and to superficial cytoskeleton changes. VK(3) treatment damages the cell nucleus and organelles, leads to the redistribution of the organelles in the perikaryon as a consequence of cytoskeletal damage, and results in cytoplasmic self-excisions. After VC:VK(3) treatment, the cells show exaggerated alterations characteristic of each vitamin treatment alone, including damaged mitochondria, self-excision of organelle-free pieces of cytoplasm, and extrusion of the perikaryon containing a nucleus surrounded by the damaged organelles. The nuclear envelope appears intact and contains chromatin that decondenses and dissipates. During the cellular demise that concludes with apparent karyolysis, the cells significantly decrease their size and alter their shape. However, the cisterns of rough endoplasmic reticulum are undamaged, but may become dilated. Since the cellular phenomena leading to cell death differ morphologically from apoptosis and necrosis, but entail self-cutting without nuclear bodies, this new form of cell death was called autoschizis. In addition, gel electrophoresis and Feulgen staining demonstrate that autoschizis is accompanied by random DNA degeneration.


Asunto(s)
Muerte Celular/fisiología , Línea Celular Tumoral/ultraestructura , Ácido Ascórbico/farmacología , Carcinoma/patología , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral/efectos de los fármacos , Fragmentación del ADN , Densitometría , Sinergismo Farmacológico , Electroforesis , Histocitoquímica , Humanos , Colorantes de Rosanilina , Neoplasias de la Vejiga Urinaria/patología , Vitamina K 3/farmacología
13.
Ultrastruct Pathol ; 29(3-4): 221-35, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16036878

RESUMEN

A prostate carcinoma cell line derived from the transgenic murine prostate cancer model (TRAMP) was treated with ascorbate (VC) alone, menadione (VK(3)) alone, or a combination of ascorbate:menadione (VC + VK(3)) for 1, 2, and 4 h. Cytotoxic cell alterations examined by light and electron microscopy were treatment-dependent with VC + VK(3) > VC > VK(3). Induced by oxidative stress, these alterations included cytokeletal changes conducive to cytoplasmic blebbing, self-excisions, and progressive nuclear alterations. While the excised parts contained ribosomes, they were devoid of nuclear fragments or other organelles. The organelle-free self-excisions caused an extreme reduction in cell size as well as chromatolysis and karyolysis that were consistent with cell death by autoschizis, but not with apoptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Ácido Ascórbico/farmacología , Vitamina K 3/farmacología , Animales , Antioxidantes/farmacología , Línea Celular Tumoral , Núcleo Celular/efectos de los fármacos , Núcleo Celular/patología , Núcleo Celular/ultraestructura , Proliferación Celular/efectos de los fármacos , Citoplasma/efectos de los fármacos , Citoplasma/patología , Citoplasma/ultraestructura , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Citoesqueleto/ultraestructura , Sinergismo Farmacológico , Masculino , Ratones , Ratones Transgénicos , Microscopía Electrónica , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/ultraestructura , Factores de Tiempo
14.
Life Sci ; 75(8): 955-67, 2004 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-15193956

RESUMEN

The tumor growth-inhibiting and chemo-potentiating effects of vitamin C and K(3)combinations have been demonstrated both in vitro and in vivo. The purpose of this study was to investigate the influence of orally administered vitamin C and K(3) on the metastasis of mouse liver tumor (T.L.T.) cells implanted in C3H mice. Adult male C3H mice were given water containing vitamin C and K3 (15 g/0.15 g dissolved in 1000 ml) beginning 2 weeks before tumor transplantation until the end of the experiment. T.L.T. cells (106) were implanted intramuscularly in the right thigh of mice. All mice were sacrificed 42 days after tumor transplantation. Primary tumor, lungs, lymph nodes and other organs or tissues suspected of harboring metastases were macroscopically examined. Samples of primary tumors, their local lymph nodes, lungs and main organs such as liver, kidneys, spleen were taken for histological examination. Forty-two percent of control mice exhibited lung metastases and 27% possessed metastases in local lymph nodes whereas 24% of vitamin-treated mice exhibited lung metastases and 10% possessed local lymph nodes metastases. The total number of lung metastases was 19 in control group and 10 in vitamin C and K(3)-treated mice. Histopathological examination of the metastatic tumors from the vitamin-treated mice revealed the presence of many tumor cells undergoing autoschizic cell death. These results demonstrate that oral vitamin C and K(3) significantly inhibited the metastases of T.L.T. tumors in C3H mice. At least a portion of this inhibition was due to tumor cell death by autoschizis.


Asunto(s)
Ácido Ascórbico/administración & dosificación , Neoplasias Hepáticas Experimentales/patología , Metástasis de la Neoplasia/prevención & control , Vitamina K 3/administración & dosificación , Adyuvantes Inmunológicos/administración & dosificación , Animales , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Masculino , Ratones , Ratones Endogámicos C3H , Trasplante de Neoplasias
15.
Tissue Cell ; 36(3): 197-209, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15140597

RESUMEN

Microscopic aspects, densitometric evaluation of Feulgen-stained DNA, and gel electrophoresis of total DNA have been used to elucidate the effects of 1, 2, and 3 h VC (ascorbic acid), VK3 (menadione), and combined VC:VK3 treatments on the cellular and nuclear morphology and DNA content of a human ovarian carcinoma cell line (MDAH 2774). Optical densitometry showed a significant decrease in cancer cell DNA content directly related to VC and VC:VK3 treatments while VK3 and VC:VK3 treated cells exhibited cytoskeletal changes that included self-excision of cytoplasmic pieces with no membranous organelles. Nuclei decreased in size and exhibited poor contrast consistent with progressive decondensation of their chromatin. Degraded chromatin was also detected in cytoplasmic autophagosomes. Nucleoli segregated their components and fragmented into small pieces. Gel electrophoretic analysis of total DNA revealed evidence of generalized DNA degradation specific to treated tumor cells. These results are consistent with previous observations [Scanning 20 (1998a) 564; Ultrastruct. Pathol. 25 (2001b) 183; J. Histochem. Cytochem. 49 (2001) 109] which demonstrated that the VC:VK3 combination induced autoschizic cell death by a series of cytoplasmic excisions without organelles along with specific nuclear ultrastructural damage.


Asunto(s)
Ácido Ascórbico/farmacología , Núcleo Celular/efectos de los fármacos , Núcleo Celular/patología , ADN de Neoplasias/metabolismo , Neoplasias Ováricas/patología , Vitamina K 3/farmacología , Antineoplásicos/farmacología , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Línea Celular , Línea Celular Tumoral , Núcleo Celular/ultraestructura , Proliferación Celular/efectos de los fármacos , Cromatina/efectos de los fármacos , Cromatina/metabolismo , Ensamble y Desensamble de Cromatina/efectos de los fármacos , Citoesqueleto/efectos de los fármacos , Citoesqueleto/metabolismo , Fragmentación del ADN/efectos de los fármacos , ADN de Neoplasias/ultraestructura , Femenino , Humanos , Membranas Intracelulares/efectos de los fármacos , Membranas Intracelulares/metabolismo , Neoplasias Ováricas/enzimología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/ultraestructura , Especies Reactivas de Oxígeno/metabolismo
16.
Biochem Pharmacol ; 67(2): 337-51, 2004 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-14698046

RESUMEN

Exponentially growing cultures of human bladder tumor cells (T24) were treated with Vitamin C (VC) alone, Vitamin K(3) (VK(3)) alone, or with a VC:VK(3) combination for 1, 2, or 4hr. Flow cytometry of T24 cells exposed to the vitamins for 1h revealed a growth arrested population and a population undergoing cell death. Cells in G(1) during vitamin treatment arrested in G(1) while those in S phase progressed through S phase and arrested in G(2)/M. DNA synthesis decreased to 14 to 21% of control levels which agreed with the percent of cells in S phase during treatment. Annexin V labeling demonstrated the majority of the cells died by autoschizis, but necrosis and apoptosis also were observed. Catalase treatment abrogated both cell cycle arrest and cell death which implicated hydrogen peroxide (H(2)O(2)) in these processes. Redox cycling of VC and VK(3) increased H(2)O(2) production and decreased cellular thiol levels and DNA content, while increasing intracellular Ca(2+) levels and lipid peroxidation. Feulgen staining of treated cells revealed a time-dependent decrease in tumor cell DNA, while electrophoresis revealed a spread pattern. These results suggest that Ca(2+) disregulation activates at least one DNase which degrades tumor cell DNA and induces tumor cell death.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Ciclo Celular/efectos de los fármacos , Vitamina K 3/farmacología , Calcio/metabolismo , ADN de Neoplasias/efectos de los fármacos , Citometría de Flujo , Humanos , Peróxido de Hidrógeno/metabolismo , Masculino , Compuestos de Sulfhidrilo/metabolismo , Células Tumorales Cultivadas , Neoplasias de la Vejiga Urinaria/patología
17.
Anticancer Res ; 23(4): 3279-87, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12926064

RESUMEN

BACKGROUND: The objective was to evaluate the cytotoxic effect and mechanism of action of vitamins C (VC) and K3 (VK3) on ovarian carcinoma. MATERIALS AND METHODS: Cytotoxicity assays were performed on ovarian cancer cell lines with VC, VK3 or a VC/VK3 combination. FIC index was employed to evaluate synergism. Flow cytometry was accomplished at 90% cytotoxic doses. Light, transmission electron microscopy and DNA isolation were performed. RESULTS: Antitumor activity was exhibited by both VC, VK3 and VC/VK3. VC/VK3 demonstrated synergistic activity. VC/VK3 may induce a G1 block in the cell cycle. Combined vitamin treatment resulted in cells that maintain apparently intact nuclei while extruding pieces of organelle-free cytoplasm. Degradation of chromosomal DNA was observed. CONCLUSION: Cell death (autoschizis) displayed characteristics of both apoptosis and necrosis. The cytotoxic effects observed may enable vitamins C and K3 to play an adjuvant role in the treatment of ovarian cancer.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Ácido Ascórbico/farmacología , Neoplasias Ováricas/tratamiento farmacológico , Vitamina K 3/farmacología , Ácido Ascórbico/administración & dosificación , División Celular/efectos de los fármacos , ADN de Neoplasias/aislamiento & purificación , ADN de Neoplasias/metabolismo , Sinergismo Farmacológico , Femenino , Citometría de Flujo , Humanos , Microscopía Electrónica , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Células Tumorales Cultivadas , Vitamina K 3/administración & dosificación
18.
Microsc Microanal ; 9(4): 311-29, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12901765

RESUMEN

Human ovarian carcinoma cells (MDAH 2774) were treated with sodium ascorbate (VC), menadione (VK3), or with a VC:VK3 combination for 1 h and then studied using light microscopy (LM) and scanning (SEM) and transmission electron (TEM) microscopy. Plasma membrane damage (blisters and blebs, hairy aspect) results from vitamin C (VC) treatment, while cytoskeletal damage and self-morsellation are caused by vitamin K3 (VK3) treatment. VC:VK3-treated cells exhibit exacerbated injuries characteristic of both VC and VK3 treatment as well as a significant decrease in cell diameters from 20-35 microm for control cells to 7-12 microm for VC:VK3 treatment. Moreover, after a 1-h exposure to the vitamin combination, autoschizis (43%), apoptosis (3%), and oncosis (1.9%) are observed at the percentages indicated. All cellular changes associated with autoschizis observed with SEM were confirmed by LM and TEM observations and are consistent with cell death by autoschizis: decrease in cell size, cytoplasmic self-excisions, degradation of the nucleus and nucleolus without formation of apoptotic bodies and, ultimately, karyorrhexis and karyolysis. These results also suggest that the vitamin combination may find clinical use in the treatment of ovarian cancer.


Asunto(s)
Ácido Ascórbico/farmacología , Muerte Celular , Neoplasias Ováricas/patología , Vitamina K 3/farmacología , Muerte Celular/efectos de los fármacos , Combinación de Medicamentos , Femenino , Humanos , Microscopía/métodos , Microscopía Electrónica de Rastreo , Neoplasias Ováricas/ultraestructura , Células Tumorales Cultivadas/efectos de los fármacos
19.
Eur J Med Chem ; 38(5): 451-7, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12767595

RESUMEN

Deficiency of alkaline and acid DNase is a hallmark in all non-necrotic cancer cells in animals and humans. These enzymes are reactivated at early stages of cancer cell death by vitamin C (acid DNase) and vitamin K(3) (alkaline DNase). Moreover, the coadministration of these vitamins (in a ratio of 100:1, for C and K(3), respectively) produced selective cancer cell death. Detailed morphological studies indicated that cell death is produced mainly by autoschizis, a new type of cancer cell death. Several mechanisms are involved in such a cell death induced by CK(3), they included: formation of H(2)O(2) during vitamins redox cycling, oxidative stress, DNA fragmentation, no caspase-3 activation, and cell membrane injury with progressive loss of organelle-free cytoplasm. Changes in the phosphorylation level of some critical proteins leading to inactivation of NF-kappaB appear as main intracellular signal transduction pathways. The increase knowledge in the mechanisms underlying cancer cells death by CK(3) may ameliorate the techniques of their in vivo administration. The aim is to prepare the introduction of the association of vitamins C and K(3) into human clinics as a new, non-toxic adjuvant cancer therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Muerte Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Ácido Ascórbico/administración & dosificación , Muerte Celular/fisiología , Quimioterapia Adyuvante , ADN/metabolismo , Sinergismo Farmacológico , Inhibidores Enzimáticos/farmacología , Humanos , FN-kappa B/metabolismo , Neoplasias/patología , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Fosforilación , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Células Tumorales Cultivadas , Vanadatos/farmacología , Vitamina K 3/administración & dosificación
20.
Biochem Pharmacol ; 63(10): 1773-83, 2002 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-12034362

RESUMEN

Vitamin C (VC) and vitamin K(3) (VK(3)) administered in a VC:VK(3) ratio of 100:1 exhibit synergistic antitumor activity and preferentially kill tumor cells by autoschizis, a novel type of necrosis characterized by exaggerated membrane damage and progressive loss of organelle-free cytoplasm through a series of self-excisions. During this process, the nucleus becomes smaller, cell size decreases one-half to one-third of its original size, and most organelles surround an intact nucleus in a narrow rim of cytoplasm. While the mitochondria are condensed, tumor cell death does not result from ATP depletion. However, vitamin treatment induces a G(1)/S block, diminishes DNA synthesis, increases H(2)O(2) production, and decreases cellular thiol levels. These effects can be prevented by the addition of catalase to scavenge the H(2)O(2). There is a concurrent 8- to 10-fold increase in intracellular Ca(2+) levels. Electrophoretic analysis of DNA reveals degradation due to the caspase-3-independent reactivation of deoxyribonuclease I and II (DNase I, DNase II). Redox cycling of the vitamins is believed to increase oxidative stress until it surpasses the reducing ability of cellular thiols and induces Ca(2+) release, which triggers activation of Ca(2+)-dependent DNase and leads to degradation of DNA. Recent experiments indicate that oral VC:VK(3) increases the life-span of tumor-bearing nude mice and significantly reduces the growth rate of solid tumors without any significant toxicity by reactivating DNase I and II and inducing autoschizis. This report discusses the mechanisms of action employed by these vitamins to induce tumor-specific death by autoschizis.


Asunto(s)
Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Muerte Celular/fisiología , Neoplasias/patología , Estrés Oxidativo/efectos de los fármacos , Vitamina K/farmacología , Animales , Antioxidantes/química , Antioxidantes/uso terapéutico , Ácido Ascórbico/química , Ácido Ascórbico/uso terapéutico , Humanos , Necrosis , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Vitamina K/química , Vitamina K/uso terapéutico
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...