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1.
Ultrastruct Pathol ; 46(5): 413-438, 2022 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-36165802

RESUMO

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.


Assuntos
Carcinoma , Neoplasias da Próstata , Androgênios , Animais , Linhagem Celular Tumoral , Diafragma/patologia , Epitélio/patologia , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Nus , Próstata/patologia , Neoplasias da Próstata/patologia
2.
Ultrastruct Pathol ; 40(5): 231-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27163289

RESUMO

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.


Assuntos
Entose/fisiologia , Neoplasias da Próstata/patologia , Animais , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Masculino , Camundongos , Microscopia Eletrônica de Transmissão
3.
Ultrastruct Pathol ; 40(4): 189-99, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27044781

RESUMO

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.


Assuntos
Carcinoma/patologia , Carcinoma/ultraestrutura , Neoplasias da Próstata/patologia , Neoplasias da Próstata/ultraestrutura , Animais , Diferenciação Celular , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Nus , Microscopia Eletrônica de Transmissão
4.
Ultrastruct Pathol ; 38(5): 315-28, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24955925

RESUMO

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.


Assuntos
Autofagia , Citoplasma/ultraestrutura , Mitocôndrias/ultraestrutura , Neoplasias da Próstata/patologia , Morte Celular , Linhagem Celular Tumoral , Humanos , Lisossomos/patologia , Masculino , Neoplasias da Próstata/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Vitamina K 3/metabolismo
5.
Ultrastruct Pathol ; 38(2): 116-40, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24460713

RESUMO

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.


Assuntos
Adenocarcinoma/ultraestrutura , Ácido Ascórbico/farmacologia , Morte Celular/efeitos dos fármacos , Neoplasias da Próstata/ultraestrutura , Vitamina K 3/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/ultraestrutura , Humanos , Masculino , Microscopia Eletrônica , Organelas/efeitos dos fármacos , Organelas/ultraestrutura
6.
Ultrastruct Pathol ; 37(6): 440-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23957452

RESUMO

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.


Assuntos
Adenocarcinoma/ultraestrutura , Neoplasias Encefálicas/ultraestrutura , Células Oxífilas/ultraestrutura , Neoplasias da Próstata/ultraestrutura , Adenocarcinoma/química , Adenocarcinoma/secundário , Neoplasias Encefálicas/química , Neoplasias Encefálicas/secundário , Linhagem Celular Tumoral , Forma do Núcleo Celular , Tamanho Celular , Glicogênio/análise , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Mitocôndrias/ultraestrutura , Células Oxífilas/química , Neoplasias da Próstata/química , Ribonucleoproteínas/análise
7.
Anat Rec (Hoboken) ; 296(1): 40-55, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23109249

RESUMO

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.


Assuntos
Proliferação de Células , Peritônio/patologia , Neoplasias da Próstata/patologia , Neoplasias da Próstata/fisiopatologia , Animais , Linhagem Celular Tumoral , Epitélio/patologia , Epitélio/fisiopatologia , Epitélio/ultraestrutura , Humanos , Masculino , Camundongos , Camundongos Nus , Microvilosidades/patologia , Microvilosidades/ultraestrutura , Invasividade Neoplásica/patologia , Invasividade Neoplásica/fisiopatologia , Invasividade Neoplásica/ultraestrutura , Neoplasias Peritoneais/fisiopatologia , Neoplasias Peritoneais/secundário , Neoplasias Peritoneais/ultraestrutura , Peritônio/fisiopatologia , Peritônio/ultraestrutura , Neoplasias da Próstata/ultraestrutura , Transplante Heterólogo
8.
Ultrastruct Pathol ; 36(5): 294-311, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23025648

RESUMO

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.


Assuntos
Adenocarcinoma/ultraestrutura , Carcinoma/ultraestrutura , Neoplasias da Próstata/ultraestrutura , Adenocarcinoma/irrigação sanguínea , Animais , Apoptose , Basófilos/ultraestrutura , Carcinoma/irrigação sanguínea , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Entose , Humanos , Vasos Linfáticos/ultraestrutura , Lisossomos/ultraestrutura , Masculino , Camundongos , Camundongos Nus , Microscopia Eletrônica de Transmissão , Invasividade Neoplásica , Transplante de Neoplasias , Fenótipo , Neoplasias da Próstata/irrigação sanguínea , Células Estromais/ultraestrutura , Transplante Heterólogo
9.
Ultrastruct Pathol ; 34(3): 140-60, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20455663

RESUMO

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.


Assuntos
Antineoplásicos/farmacologia , Ácido Ascórbico/farmacologia , Morte Celular/efeitos dos fármacos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Vitamina K 3/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/ultraestrutura , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA , Ensaios de Seleção de Medicamentos Antitumorais , Quimioterapia Combinada , Humanos , Masculino , Microscopia Eletrônica de Transmissão , Organelas/efeitos dos fármacos , Organelas/ultraestrutura , Estresse Oxidativo/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo , Neoplasias da Bexiga Urinária/patologia
10.
J Histochem Cytochem ; 58(7): 635-51, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20385787

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácido Ascórbico/farmacologia , Carcinoma/ultraestrutura , Nucléolo Celular/ultraestrutura , Proteínas Cromossômicas não Histona/análise , Neoplasias da Bexiga Urinária/ultraestrutura , Vitamina K 3/farmacologia , Carcinoma/química , Linhagem Celular Tumoral , Nucléolo Celular/química , Nucléolo Celular/efeitos dos fármacos , Humanos , Neoplasias da Bexiga Urinária/química , Vitamina K/farmacologia
11.
Int J Med Sci ; 5(2): 62-7, 2008 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-18392145

RESUMO

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.


Assuntos
Ácido Ascórbico/uso terapêutico , Neoplasias da Próstata/tratamento farmacológico , Vitamina K 3/uso terapêutico , Administração Oral , Idoso , Ácido Ascórbico/administração & dosagem , Quimioterapia Combinada , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Salvação , Vitamina K 3/administração & dosagem
12.
Anat Rec A Discov Mol Cell Evol Biol ; 288(1): 58-83, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16345077

RESUMO

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.


Assuntos
Morte Celular/fisiologia , Linhagem Celular Tumoral/ultraestrutura , Ácido Ascórbico/farmacologia , Carcinoma/patologia , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Fragmentação do DNA , Densitometria , Sinergismo Farmacológico , Eletroforese , Histocitoquímica , Humanos , Corantes de Rosanilina , Neoplasias da Bexiga Urinária/patologia , Vitamina K 3/farmacologia
13.
Ultrastruct Pathol ; 29(3-4): 221-35, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16036878

RESUMO

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.


Assuntos
Apoptose/efeitos dos fármacos , Ácido Ascórbico/farmacologia , Vitamina K 3/farmacologia , Animais , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Núcleo Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Citoplasma/patologia , Citoplasma/ultraestrutura , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Citoesqueleto/ultraestrutura , Sinergismo Farmacológico , Masculino , Camundongos , Camundongos Transgênicos , Microscopia Eletrônica , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Neoplasias da Próstata/ultraestrutura , Fatores de Tempo
14.
Life Sci ; 75(8): 955-67, 2004 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-15193956

RESUMO

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.


Assuntos
Ácido Ascórbico/administração & dosagem , Neoplasias Hepáticas Experimentais/patologia , Metástase Neoplásica/prevenção & controle , Vitamina K 3/administração & dosagem , Adjuvantes Imunológicos/administração & dosagem , Animais , Neoplasias Hepáticas Experimentais/tratamento farmacológico , Masculino , Camundongos , Camundongos Endogâmicos C3H , Transplante de Neoplasias
15.
Tissue Cell ; 36(3): 197-209, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15140597

RESUMO

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.


Assuntos
Ácido Ascórbico/farmacologia , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , DNA de Neoplasias/metabolismo , Neoplasias Ovarianas/patologia , Vitamina K 3/farmacologia , Antineoplásicos/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Núcleo Celular/ultraestrutura , Proliferação de Células/efeitos dos fármacos , Cromatina/efeitos dos fármacos , Cromatina/metabolismo , Montagem e Desmontagem da Cromatina/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Fragmentação do DNA/efeitos dos fármacos , DNA de Neoplasias/ultraestrutura , Feminino , Humanos , Membranas Intracelulares/efeitos dos fármacos , Membranas Intracelulares/metabolismo , Neoplasias Ovarianas/enzimologia , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/ultraestrutura , Espécies Reativas de Oxigênio/metabolismo
16.
Biochem Pharmacol ; 67(2): 337-51, 2004 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-14698046

RESUMO

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.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Ciclo Celular/efeitos dos fármacos , Vitamina K 3/farmacologia , Cálcio/metabolismo , DNA de Neoplasias/efeitos dos fármacos , Citometria de Fluxo , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Compostos de Sulfidrila/metabolismo , Células Tumorais Cultivadas , Neoplasias da Bexiga Urinária/patologia
17.
Anticancer Res ; 23(4): 3279-87, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12926064

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Ácido Ascórbico/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Vitamina K 3/farmacologia , Ácido Ascórbico/administração & dosagem , Divisão Celular/efeitos dos fármacos , DNA de Neoplasias/isolamento & purificação , DNA de Neoplasias/metabolismo , Sinergismo Farmacológico , Feminino , Citometria de Fluxo , Humanos , Microscopia Eletrônica , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas , Vitamina K 3/administração & dosagem
18.
Microsc Microanal ; 9(4): 311-29, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12901765

RESUMO

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.


Assuntos
Ácido Ascórbico/farmacologia , Morte Celular , Neoplasias Ovarianas/patologia , Vitamina K 3/farmacologia , Morte Celular/efeitos dos fármacos , Combinação de Medicamentos , Feminino , Humanos , Microscopia/métodos , Microscopia Eletrônica de Varredura , Neoplasias Ovarianas/ultraestrutura , Células Tumorais Cultivadas/efeitos dos fármacos
19.
Eur J Med Chem ; 38(5): 451-7, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12767595

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Morte Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Ácido Ascórbico/administração & dosagem , Morte Celular/fisiologia , Quimioterapia Adjuvante , DNA/metabolismo , Sinergismo Farmacológico , Inibidores Enzimáticos/farmacologia , Humanos , NF-kappa B/metabolismo , Neoplasias/patologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Células Tumorais Cultivadas , Vanadatos/farmacologia , Vitamina K 3/administração & dosagem
20.
Biochem Pharmacol ; 63(10): 1773-83, 2002 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-12034362

RESUMO

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.


Assuntos
Antioxidantes/farmacologia , Ácido Ascórbico/farmacologia , Morte Celular/fisiologia , Neoplasias/patologia , Estresse Oxidativo/efeitos dos fármacos , Vitamina K/farmacologia , Animais , Antioxidantes/química , Antioxidantes/uso terapêutico , Ácido Ascórbico/química , Ácido Ascórbico/uso terapêutico , Humanos , Necrose , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Vitamina K/química , Vitamina K/uso terapêutico
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