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1.
Exp Oncol ; 45(1): 130-136, 2023 06 26.
Artigo em Inglês | MEDLINE | ID: mdl-37417273

RESUMO

Studying the biological characteristics of bladder cancer in primary culture can be an effective way for diagnostic and prognostic purposes, as well as choosing a scheme for personalized therapy. AIM: To characterize and compare 2D and 3D primary cell cultures obtained from the same tumor sample resected from a patient with high-grade bladder cancer. MATERIALS AND METHODS: 2D and 3D primary cell cultures were obtained from explants of resected bladder cancer. Glucose metabolism, lactate dehydrogenase (LDH) activity, and level of apoptosis were studied. RESULTS: Multicellular tumor spheroids (3D) differ from planar culture (2D) by more pronounced consumption of glucose from the culture medium (1.7 times higher than 2D on Day 3 of culture), increased lactate dehydrogenase activity (2.5 times higher on Day 3 vs. Day 1 of cultivation, while in 2D culture LDH activity is constant), stronger acidification of the extracellular environment (pH dropped by 1 in 3D and by 0.5 in 2D). Spheroids demonstrate enhanced resistance to apoptosis (1.4 times higher). CONCLUSION: This methodological technique can be used both for tumor characterization and for selection of optimal postoperative chemotherapeutic schemes.


Assuntos
Técnicas de Cultura de Células , Neoplasias da Bexiga Urinária , Humanos , Técnicas de Cultura de Células/métodos , Cultura Primária de Células , Esferoides Celulares , Lactato Desidrogenases , Linhagem Celular Tumoral
2.
BBA Adv ; 3: 100072, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37082262

RESUMO

Background: Fibrinogen is a large polyfunctional plasma protein consisting of a number of structural and functional domains. Among them, two αC-domains, each formed by the amino acid residues Аα392-610, are involved in fibrin polymerization, activation of fibrinolysis, platelet aggregation, and interaction with different cell types. Previous study revealed that each fibrinogen αC-domain consists of the N-terminal and C-terminal sub-domains. The major objections of the present study were to test functional role of these sub-domains in the above mentioned processes. Methods: To achieve these objections, we used specific proteases to prepare two truncated forms of fibrinogen, fibrinogen desAα505-610 and fibrinogen desAα414-610, missing their N-terminal and both N- and C-terminal sub-domains, respectively. Results: Our study with these truncated forms using turbidity measurements and electron microscopy revealed that the N- and C-terminal subdomains both contribute to protofibril formation and their lateral aggregation into fibers during fibrin polymerization process. These two sub-domains also contributed to platelet aggregation with the N-terminal sub-domains playing a more significant role in this process. At the same time, the C-terminal sub-domains make the major contribution to the plasminogen activation process. Further, our experiments revealed that the C-terminal sub-domains are involved in endothelial cell viability and migration of cancer cells. Conclusions: Thus, the results obtained establish the functional role of individual sub-domains of the αC-domains in fibrin polymerization, activation of fibrinolytic system, platelet aggregation, and cellular interactions. General significance: The present study expands our understanding of the functional role of individual fibrinogen domains and their specific portions in various fibrin(ogen)-dependent processes.

3.
Exp Oncol ; 44(3): 213-216, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36325705

RESUMO

BACKGROUND: The anticancer effects of phytohormones of cytokinin nature are similar to those of medicinal mushrooms, which are able to synthesize cytokinins in large amounts. AIM: To determine the antiproliferative effect of crude extracts and cytokinin fractions from the mycelial biomass of seven fungi species on colon cancer cells in vitro. MATERIALS AND METHODS: Cytokinin content in mycelial biomass of Ganoderma lucidum, Lentinula edodes, Trametes versicolor, Pleurotus ostreatus, Morchella esculenta, Hericium coralloides, and Fomitopsis officinalis was determined by high performance liquid chromatography mass spectrometry. The antiproliferative effect of the mushroom extracts on the human colon adenocarcinoma Colo 205 cells was assessed by MTT-test. RESULTS: The content of cytokinins (trans-zeatin, zeatin riboside, isopentenyladenosine, isopentenyladenine and zeatin-O-glucoside) was determined in the mycelial biomass of the medicinal macromycetes. Zeatin-type hormones prevailed in all species, though trans-zeatin was the most abundant in H. coralloides and M. esculenta. In P. ostreatus, only zeatin-O-glucoside was detected. The lowest IC50 was found for both the cytokinin fraction (0.21 µg/ml) and the crude extract (0.17 µg/ml) from mycelial biomass of H. coralloides. F. officinalis also demonstrated high antiproliferative effect against Colo 205 cells: IC50 was 0.9 µg/ml for the crude extract and almost twice lower for the cytokinin fraction. In the studied concentration range (0.016-2 µg/ml), the crude extracts from G. lucidum and M. esculenta and the cytokinin fraction from L. edodes did not reach IC50 values. CONCLUSIONS: The present study showed that crude extracts and/or cytokinin fractions of several medicinal Basidiomycetes species are capable to inhibit proliferation of colon cancer cells in vitro. Crude extract cytotoxicity of H. coralloides, P. ostreatus and T. versicolor was higher than that of cytokinin fraction while antiproliferative effect of cytokinin fraction from F. officinalis was higher than that in its crude extract.


Assuntos
Adenocarcinoma , Neoplasias do Colo , Humanos , Zeatina , Biomassa , Trametes , Neoplasias do Colo/tratamento farmacológico , Citocininas/química , Misturas Complexas
4.
Exp Oncol ; 43(2): 142-148, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34190522

RESUMO

BACKGROUND: The bladder cancer is immunogenic, and neoantigens generated by tumor cells trigger a notable immune response in the host. On the other hand, multiple immune escape mechanisms allow for avoiding the recognition by the host immune system. Toll-like receptor type 4 and inflammatory cytokines play major role in the immune response to bladder cancer. AIM: To assess the expression of TLR4 and the genes of major inflammatory cytokines in tumor cells and in unaffected tissue of the bladder. MATERIALS AND METHODS: The pairs of samples from the urinary bladder tumor and unaffected adjacent tissue were obtained from 50 surgically treated patients with bladder cancer. The level of expression of TLR4, TGF-ß1, INF-γ, TNF-α genes was evaluated by real-time polymerase chain reaction. RESULTS: Bladder cancer cells are characterized by lower expression levels of TLR4, TGF-ß1, INF-γ, TNF-α as compared to unaffected tissue. In patients with recurrent cancer, expression of TLR-4 and cytokines does not change both in tumor and in unaffected tissue of the bladder. Expression of TLR4 is identically low both in low- and high-grade cancer. Expression levels of the INF-γ and TNF-α are remarkably low in muscle-invasive cancer compared to the unaffected bladder tissue. The level of TGF-ß1 in bladder cancer is comparable to the unaffected tissue of the bladder, while in the intact and metastatic lymph nodes it is significantly upregulated. CONCLUSION: Bladder cancer tissue differs from the unaffected part of the bladder wall in the level of TLR4, TGF-ß1, INF-γ, TNF-α expression.


Assuntos
Citocinas/biossíntese , Receptor 4 Toll-Like/biossíntese , Evasão Tumoral/imunologia , Neoplasias da Bexiga Urinária/imunologia , Adulto , Idoso , Citocinas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Receptor 4 Toll-Like/imunologia , Neoplasias da Bexiga Urinária/patologia
5.
Exp Oncol ; 43(1): 7-14, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33785718

RESUMO

BACKGROUND: Toll-like receptor 4 (TLR4) is known to be involved in carcinogenesis and cancer progression. Changes in TLR4 expression are associated with changes in the expression of key cellular cytokines (transforming growth factor-ß (TGF-ß), tumor necrosis factor-α (TNF-α), interferon-γ (IFN-γ)), which affect cancer progression and metastasis. AIM: To study changes in the expression of TLR4, TGF-ß, TNF-α, IFN-γ genes, the level of apoptosis and cell cycle distribution in human invasive urothelial carcinoma T24/83 cells under the treatment with polyphenolic adjuvant compound of fungal origin melanin, cytotoxic drug cisplatin, and combination of both. MATERIALS AND METHODS: T24/83 cells were incubated with cisplatin (0.05 mM), melanin (5 µg/ml), or their combination. The expression level of TLR-4, TGF-ß, INF-γ, TNF-α was evaluated by the real time polymerase chain reaction. The flow cytometry was used to study cell cycle distribution, proliferative activity and level of apoptosis. Morphological analysis of the Т24/83 cells was performed as well. RESULTS: Melanin, cisplatin, and their combination downregulate TLR4 expression (2.67; 1.28; and 2.73-fold decrease, respectively) and TNF-α expression (6.5; 1.4; and 1.7-fold decrease, respectively). Melanin did not affect TGF-ß expression while cisplatin caused 13-fold downregulation of TGF-ß. The combined use of cisplatin and melanin decreased TGF-ß expression by 6.5 times. The upregulation of IFN-γ by melanin, cisplatin, and their combination was demonstrated (4.3; 6.7; and 2-fold increase, respectively). All treatment modalities increased the level of apoptosis in T24/83 cells. Melanin treatment increased significantly the proportion of fibroblast-like cells in T24/83 culture with decreased cell adhesion to the substrate. CONCLUSIONS: Melanin, cisplatin, and combination of both agents affect significantly TLR4, TNF-α, TGF-ß, INF-γ expression, cell cycle distribution and morphology in T24/83 cells suggesting their transition to less aggressive phenotype.


Assuntos
Antineoplásicos/farmacologia , Carcinoma de Células de Transição/patologia , Cisplatino/farmacologia , Melaninas/farmacologia , Neoplasias da Bexiga Urinária/patologia , Carcinoma de Células de Transição/metabolismo , Linhagem Celular Tumoral , Humanos , Interferon gama/efeitos dos fármacos , Receptor 4 Toll-Like/efeitos dos fármacos , Fator de Crescimento Transformador beta/efeitos dos fármacos , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Neoplasias da Bexiga Urinária/metabolismo
6.
J Inorg Biochem ; 168: 98-106, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28086144

RESUMO

Four novel Pd2+ and Pt2+ mononuclear π-coordination compounds with general formula [M(HL)1,2Cl2], M=Pd2+, Pt2+ have been synthesized by reaction of [PdCl4]2-, [PtCl4]2- anions with N-allyl-4-morpholinethiocarboxamide (HL1) and N-Allyl-N'-tert-butylthiourea (HL2). All complexes have been characterized by single-crystal X-ray diffraction study and 1H, 13C NMR spectroscopy. Cytotoxic, cytostatic and proapoptotic activities of compounds have been determined in vitro on HeLa cell line and compared with cisplatin as etalon drug. All complex compounds possessed pronounced cytotoxic activity with IC50 indexes in range of 2·10-6-1.5·10-4М (IC50 of cisplatin is 5.7∙10-5М) and showed proapoptotic, cytostatic and antisyntetic influence higher or comparable with cisplatin. The comparative influence of cisplatin and synthesized metal complexes on pTZ19R* plasmid DNA was monitored by agarose gel electrophoresis. All compounds showed high affinity to DNA that correlates with observed cytostatic and proapoptotic levels. In general Pd(II) compounds showed higher activity than Pt(II) ones.


Assuntos
Complexos de Coordenação/síntese química , Complexos de Coordenação/farmacologia , DNA/química , Paládio/química , Platina/química , Tioureia/análogos & derivados , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/química , Células HeLa , Humanos , Concentração Inibidora 50 , Tioureia/química , Difração de Raios X
7.
Ukr Biochem J ; 88(4): 12-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-29235752

RESUMO

The mechanisms of VEGF-mediated effects on endothelial cells during cancer development and progression is not clear. In present study the biological effects of VEGF, VEGF-rich culture medium of peritoneal macrophages from mice with Lewis lung carcinoma were studied on MAEC cell line under conditions of unfed culture. We have shown that VEGF increased cell proliferation by the 5th day of culturing vs control and anti-VEGF-treated cells. This effect was associated with increased consumption of glucose and NO production by the 2nd day while decreased ­ on the 5th day of cell culturing. VEGF-mediated NO production was dependent on Ca2+ ions. Block of Ca2+-channels (LaCl3) had more pronounced inhibitory effect vs chelator of Ca2+ ions (EDTA). It was shown that peritoneal macrophages are the main suppliers of VEGF at tumor angiogenesis, as evidenced by the data obtained on model system of endothelial cells synchronized in G0/G1 phase.


Assuntos
Cálcio/metabolismo , Carcinoma Pulmonar de Lewis/metabolismo , Células Endoteliais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Neovascularização Patológica/metabolismo , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Anticorpos Monoclonais/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Transformada , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Cocultura , Meios de Cultivo Condicionados/química , Meios de Cultivo Condicionados/farmacologia , Ácido Edético/farmacologia , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Glucose/metabolismo , Lantânio/farmacologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/patologia , Camundongos , Neovascularização Patológica/patologia , Óxido Nítrico/biossíntese , Cultura Primária de Células , Fator A de Crescimento do Endotélio Vascular/biossíntese
8.
Ukr Biochem J ; 87(1): 64-74, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26036132

RESUMO

Pd(I) and Ni(II) complex compounds: [Pd(AMMT)2]Cl2 (1), [Pd(AMMT)4]Cl2 (2) and [Ni(AMMT)2(H2O)](NO3)2 (3) with 4-amino-3-mercapto-5-methyl-1,2,4-triazole (AMMT) have been synthesized. The spectral characteristics of 1, 2 were studied by 1H (13C) NMR and UV-Vis spectroscopy. X-ray diffraction studies established that all complexes contain the AMMT molecule, which are coordinated to the central metal ion in the thione tautomeric form. At the ratio M: L = 1:2 ligand is coordinated in bidentate chelate manner by the nitrogen of amino- and sulfur of mercapto group (compounds 1, 3). But the molar ratio M: L = 1:4 leads to monodentate coordination of AMMT molecules only by sulfur of mercaptogroup (complex 2). Vacant coordination sites of the metal ion are occupied by water molecules (complex 3). The screening of complexes 1-3 and starting compounds [AMMT, K2PdCl4 (4), Ni(NO3)2 · 6H2O (5)] by their mitochondrial dehydrogenase activity have been performed by us for the first time, resulting in established that the Pd(II) complexes (1, 2), Pd(II) salt (4) and AMMT normalize the activity of mitochondrial dehydrogenases of cancer HeLa cells, identified by MTT-test. In contrast, the Ni(II) complex (3) and Ni(II) salt (5) do not stimulate the activity of mitochondrial dehydrogenases. It has been found, that all investigated compounds do not affect on the cell cycle and the level of apoptotic cells as well as do not show a toxic effect. Thus, these results indicate that AMMT and Pd(II) complexes may be used as modifiers of mitochondrial respiration, which dysfunction is particularly evident in the tumor cells.


Assuntos
Complexos de Coordenação/farmacologia , Mitocôndrias/efeitos dos fármacos , Níquel/química , Oxirredutases/metabolismo , Paládio/química , Triazóis/química , Cátions Bivalentes , Ciclo Celular/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Células HeLa , Humanos , Mitocôndrias/enzimologia , Proteínas Mitocondriais/agonistas , Proteínas Mitocondriais/metabolismo
9.
Tsitol Genet ; 48(6): 56-61, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25536823

RESUMO

We investigated the effects of teichoic acid (TA) from Staphylococcus aureus Wood 46 on tumor growth and metastasis of the experimental Lewis lung carcinoma (LLC) in mice. Intranasal administration of TA alone aggravated both tumor growth and metastasis, whereas combined administration of TA with a synthetic bimetallic (copper : cadmium) ethylene diamine complex PO244 resulted in pronounced antitumor and antimetastatic effects. The group of animals subjected to the combined treatment with TA and PO244 manifested the highest degree of lymphocyte infiltration into the tumor tissue, compared to the control group and those exposed to TA or PO244 alone. Moreover, the combined treatment negatively affected the adhesive properties of peritoneal macrophages in the LLC bearing mice. Co-cultivation of the isolated macrophages with primary LLC cultures revealed significant (p < 0.05) cytotoxic and cytostatic effects, detected as an increased level of apoptosis and a reduced fraction of replicating cells.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Macrófagos Peritoneais/efeitos dos fármacos , Staphylococcus aureus/química , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Cádmio/química , Carcinoma Pulmonar de Lewis/patologia , Ciclo Celular/efeitos dos fármacos , Técnicas de Cocultura , Complexos de Coordenação/administração & dosagem , Complexos de Coordenação/química , Cobre/química , Etilenodiaminas/química , Macrófagos Peritoneais/patologia , Camundongos Endogâmicos C57BL , Metástase Neoplásica , Cultura Primária de Células , Ácidos Teicoicos/administração & dosagem , Células Tumorais Cultivadas
10.
Eksp Klin Farmakol ; 76(8): 39-42, 2013.
Artigo em Russo | MEDLINE | ID: mdl-24228489

RESUMO

The cytostatic/cytotoxic effects of the maleimide derivative 1-(4-Cl-Benzyl)-3-Cl-4-(CF3-phenylamino)-1H-pyrrol-2,5-dione (MI-1) have been estimated on epithelial derived human cell cultures (Colo 205, MCF-7, and Hela). The anticancer and toxic effects of MI-1 have been investigated on DMH-induced cancer development and normal colon morphology in rats. The results showed that the compound studied has low cytotoxicity but produces a strong antiproliferative effect on cell cultures and partially suppresses colon cancer development in DMH-induced model. The MI-1 effect on normal colon mucosa is insignificant, and no destructive changes have been detected in the intestine of rats. This maleimide derivate can be considered as a promising anticancer drug.


Assuntos
Compostos de Anilina/farmacologia , Antineoplásicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Citotoxinas/farmacologia , Ácidos Linoleicos/farmacologia , Maleimidas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Pirróis/farmacologia , Compostos de Anilina/química , Animais , Antineoplásicos/química , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Citotoxinas/química , Dimenidrinato/toxicidade , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Ácidos Linoleicos/química , Masculino , Maleimidas/química , Alcamidas Poli-Insaturadas/química , Pirróis/química , Ratos
11.
Eksp Klin Farmakol ; 72(4): 28-32, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19803367

RESUMO

Effects of the nootropic neuropeptide drugs cerebrolysin (Ebewe, Austria) and cortexin (Geterofarm, Russia) on the immunocompetent cells (T-lymphocytes of the MT-4 cell line and B-lymphocytes of the Raji cell line) were studied in vitro. The cell viability was evaluated using the MTT test by counting living and dead cells upon incubation under various conditions with a vital stain (Trypan Blue). It is established that cerebrolysin exhibits cytoprotective properties with respect to both T- and B-lymphocytes and favors the survival of immunocompetent cells. In addition, cerebrolysin in certain concentrations produces a proliferative effect on B-lymphocytes, thus stimulating the formation of immune memory B cells. In contrast, cortexin in certain concentrations produces a cytotoxic and antiproliferative action on T-lymphocytes. The parameters of influence for both drugs depend on their concentration in the cell incubation medium, the duration of action, and (most significantly) the cell type. These properties may account for one of the possible mechanisms of the immunoprotective action of cerebrolysin in various neurological states accompanied by immune response disorders.


Assuntos
Aminoácidos/farmacologia , Linfócitos B/imunologia , Proliferação de Células/efeitos dos fármacos , Ativação Linfocitária/efeitos dos fármacos , Nootrópicos/farmacologia , Peptídeos/farmacologia , Aminoácidos/imunologia , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Citoproteção/efeitos dos fármacos , Citoproteção/imunologia , Relação Dose-Resposta a Droga , Humanos , Memória Imunológica/efeitos dos fármacos , Memória Imunológica/imunologia , Peptídeos e Proteínas de Sinalização Intercelular , Ativação Linfocitária/imunologia , Camundongos , Nootrópicos/imunologia , Peptídeos/imunologia , Linfócitos T
12.
Tsitol Genet ; 43(5): 14-21, 2009.
Artigo em Russo | MEDLINE | ID: mdl-20458961

RESUMO

A cocultivation system was developed to investigate the interactions between MCF-7 breast cancer epithelial cells and MT-4 (line human T-cell leukemia) by paracrine mechanism (no contact cocultivation). Viability and proliferation were determined in two fractions of MCF-7 cells from spheroid culture and monolayer. It has been shown that the influence of MT-4 reduced the number of cells MCF-7 in fraction of adhesive cells and did not influence on the suspension fraction. Proliferation was reduced in both fractions without MT-4. Cells viability was different in monolayer and spheroids with MT-4 and without MT-4; in monolayer it was lower, in spheroids it was higher. We think that, MT-4 by paracrine signal way stimulated proliferation MCF 7 cells, reduced adhesive to the bottom and led to MTS formation.


Assuntos
Proliferação de Células , Técnicas de Cocultura , Comunicação Parácrina , Adesão Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Meios de Cultura , Humanos , Cinética , Esferoides Celulares
13.
Bull Exp Biol Med ; 138(3): 295-7, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15665927

RESUMO

Growth and metastasizing of Lewis lung carcinoma were accompanied by complex changes in tumor sensitivity to cisplatin. On day 17 of growth, tumor sensitivity was much lower than immediately after transplantation. Further growth of Lewis lung carcinoma was accompanied by a progressive increase in its sensitivity to cytostatic treatment. The study of migration activity of the tumor and dynamics of metastasizing showed that metastatically active carcinoma cells dominated on day 17 of tumor growth, but then the number of these cells progressively decreased to the 29th day of tumor growth. Growth-related changes in the sensitivity of Lewis lung carcinoma were probably due to complex variations in the number of metastatically active tumor cells with high resistance to cisplatin.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Carcinoma Pulmonar de Lewis/patologia , Cisplatino/uso terapêutico , Animais , Resistencia a Medicamentos Antineoplásicos , Camundongos , Metástase Neoplásica
14.
Mol Biol (Mosk) ; 27(4): 833-8, 1993.
Artigo em Russo | MEDLINE | ID: mdl-8361491

RESUMO

Cells of human epidermoid carcinoma A431 were used for obtaining of the cell line constantly expressing TGF-alpha. Recombinant virions were obtained by introducing the proviral DNA into PA317 cells by means of electrotransfection. A protein with the EGF-competing activity was found in a conditioned media of the chosen clone A431/1522-4. The concentration of this protein was several times higher than in a conditioned media of wild type A431 cells. By means of electrophoresis, isoelectric focusing, and immunochemical analysis it was shown that the protein is TGF-alpha. Similarly to EGF, the extracted TGF-alpha entirely displaced 125I-EGF specifically bound to receptor. TGF-alpha produced by the A431/1522 cells also stimulated autophosphorylation of the EGF receptor.


Assuntos
Expressão Gênica , Vetores Genéticos , Retroviridae/genética , Fator de Crescimento Transformador alfa/genética , Autorradiografia , Southern Blotting , Eletroforese em Gel de Poliacrilamida , Humanos , Radioisótopos do Iodo , Focalização Isoelétrica , Fator de Crescimento Transformador alfa/análise , Células Tumorais Cultivadas
15.
Eksp Onkol ; 12(5): 15-8, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2226252

RESUMO

A sharp decrease in the number of epidermal growth factor receptors (EGF-R) in the rat liver plasma membranes had been found at different stages of diethylnitrosamine-induced carcinogenesis. The complete loss of high-affinity binding sites for EGF did not prevent EGF-dependent autophosphorylation of EGF-R. Hepatocytes from the rat liver tumors in the primary culture had two classes of EGF-R: high and low affinity ones, though their number had been twice less than in the normal hepatocytes. The dynamics of internalization and down-regulation of EGF-R was very similar in the primary culture of transformed and normal hepatocytes. It testifies that there are some factors of microenvironment in the liver during carcinogenesis which cause the loss of EGF-R (down-regulation) and a decrease of their affinity (activation of protein kinase C). A possible autocrine or paracrine nature of these factors is discussed.


Assuntos
Dietilnitrosamina/toxicidade , Receptores ErbB/efeitos dos fármacos , Neoplasias Hepáticas Experimentais/metabolismo , Fígado/efeitos dos fármacos , Animais , Membrana Celular/química , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/fisiologia , Fator de Crescimento Epidérmico/metabolismo , Receptores ErbB/análise , Receptores ErbB/metabolismo , Fígado/química , Fígado/metabolismo , Neoplasias Hepáticas Experimentais/induzido quimicamente , Masculino , Fosforilação/efeitos dos fármacos , Ratos
16.
Eksp Onkol ; 12(4): 17-21, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2199185

RESUMO

It has been established for the first time that in extracts of the regenerating and preneoplastic (4 months after the beginning of carcinogen introduction) intestine as well as in the peritumor tissue the content of EPR-similar polypeptides and insulin raises, whereas in tumours it remains not high. Proteins with molecular weight greater than 120 kD able to compete with 125I-EPR for the binding with the receptors of EPR and being, evidently, the precursors of EPP are found in case of carcinogenesis. Besides, the content of insulin receptors rises, this process being most typical of the large intestine.


Assuntos
Fator de Crescimento Epidérmico/análise , Receptores ErbB/análise , Mucosa Intestinal/análise , Neoplasias Intestinais/análise , Lesões Pré-Cancerosas/análise , Precursores de Proteínas/análise , Animais , Cromatografia em Gel , Eletroforese , Insulina/análise , Masculino , Ratos , Receptor de Insulina/análise , Regeneração
17.
Eksp Onkol ; 12(6): 31-3, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2261874

RESUMO

It has been determined that concentration of EGF-like substances in the liver of rats with N-diethylnitrosamine-induced hepatocarcinogenesis increases and reaches its maximum in tumours (50-150 ng/mg protein). In the regenerating liver the amount of these peptides does not exceed 10 ng/mg protein. High pressure gel-filtration of appropriate extracts has revealed EGF-competing substances with m. w. about 20-30 kD in the liver carcinomas. The presented data confirm that registered EGF-like substances belong to TGF-alpha peptides.


Assuntos
Fator de Crescimento Epidérmico/análise , Neoplasias Hepáticas Experimentais/metabolismo , Fígado/química , Fator de Crescimento Transformador alfa/análise , Animais , Cromatografia em Gel , Dietilnitrosamina , Neoplasias Hepáticas Experimentais/induzido quimicamente , Regeneração Hepática , Camundongos , Ratos , Células Tumorais Cultivadas
18.
Tsitologiia ; 31(4): 453-9, 1989 Apr.
Artigo em Russo | MEDLINE | ID: mdl-2787940

RESUMO

The number of epidermal growth factor (EGF) receptors was determined for rat's hepatocytes under condition of their regeneratory proliferation, following a partial hepatectomy. In the normal hepatocytes two classes of EGF-receptors are distinguished, with high and low affinity, respectively. As early as 2 hours after the partial hepatectomy the total number of EGF-receptors sharply decreases, those with high affinity being not determined at all. The patterns of autophosphorylation of EGF-receptors with low affinity, examined in regenerating liver hepatocytes, remained the same as in the intact liver: their kinase activity was EGF-dependent, tyrosine residues of receptor molecules, with molecular mass equal to 150-170 kDa, underwent phosphorylation.


Assuntos
Receptores ErbB/metabolismo , Regeneração Hepática , Fígado/metabolismo , Animais , Fator de Crescimento Epidérmico/metabolismo , Hepatectomia , Masculino , Fosforilação , Ratos
19.
Eksp Onkol ; 11(4): 16-20, 1989.
Artigo em Russo | MEDLINE | ID: mdl-2788074

RESUMO

The production of EGF and EGF-like polypeptides in the normal intestinal mucosa and during 1,2-dimethylhydrazine (DMH)-induced carcinogenesis and postresection regeneration was studied in albino rats using chromatographic separation of acid-ethanol extracts. Fractions after gel filtration on Biogel P-60 with subsequent reverse-phase high performance liquid chromatography in acetonitrile gradient were tested in radioreceptor assay for competition with EGF. It has been established that intestinal tumours induced by DMH and regenerating intestinal mucosa have amplified production of EGF--alpha-TGF and related proteins of high molecular weight (approx. 30; 45-55; 120 kD) with the EGF-competitive activity. It is supposed that the high molecular weight EGF-competitive material represents nonprocessed forms of EGF and/or alpha-TGF which are accumulated in rapidly proliferating low-differentiated cells due to the intensified expression of their genes.


Assuntos
Carcinógenos/toxicidade , Dimetilidrazinas/toxicidade , Fator de Crescimento Epidérmico/biossíntese , Mucosa Intestinal/efeitos dos fármacos , Neoplasias Intestinais/metabolismo , Intestino Delgado , Metilidrazinas/toxicidade , Biossíntese Peptídica , Regeneração/efeitos dos fármacos , 1,2-Dimetilidrazina , Animais , Cromatografia Líquida de Alta Pressão , Fator de Crescimento Epidérmico/análise , Hiperplasia/metabolismo , Mucosa Intestinal/análise , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/análise , Neoplasias Intestinais/induzido quimicamente , Neoplasias Intestinais/cirurgia , Intestino Delgado/análise , Intestino Delgado/metabolismo , Intestino Delgado/cirurgia , Masculino , Peso Molecular , Peptídeos/análise , Ratos , Fatores de Tempo
20.
Eksp Onkol ; 9(3): 17-20, 1987.
Artigo em Russo | MEDLINE | ID: mdl-3497021

RESUMO

The radioimmunological and radioreceptor methods have been used to show that sialadenectomy leads to the stable decrease of the epidermal growth factor (EGF) concentration in saliva and blood serum. The mean number of colon tumours per rat was significantly lower among the rats which had been sialadenectomized before injections of the carcinogen, than in the control. But a sharp stimulation of carcinogenesis in the duodenal mucosa was observed after sialadenectomy. The production of the alpha-transforming growth factor with the EGF-competing activity for the EGF-receptors was found in the chemically-induced rat colon tumours.


Assuntos
Fator de Crescimento Epidérmico/metabolismo , Mucosa Intestinal/metabolismo , Neoplasias Intestinais/induzido quimicamente , 1,2-Dimetilidrazina , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/patologia , Adenocarcinoma/fisiopatologia , Animais , Dimetilidrazinas , Fator de Crescimento Epidérmico/isolamento & purificação , Neoplasias Intestinais/metabolismo , Neoplasias Intestinais/fisiopatologia , Masculino , Peptídeos/isolamento & purificação , Peptídeos/metabolismo , Ratos , Glândula Submandibular/metabolismo , Fatores de Crescimento Transformadores
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