RESUMO
Modifications of epigenetic factors affect our lives and can give important information regarding one's state of health. In cancer, epigenetic modifications play a crucial role, as they influence various programmed cell death types. The purpose of this review is to investigate how epigenetic modifications, such as DNA methylation, histone modifications, and non-coding RNAs, influence various cell death processes in suppressing or promoting cancer development. Autophagy and apoptosis are the most investigated programmed cell death modes, as based on the tumor stage these cell death types can either promote or prevent cancer evolution. Therefore, our discussion focuses on how epigenetic modifications affect autophagy and apoptosis, as well as their diagnostic and therapeutical potential in combination with available chemotherapeutics. Additionally, we summarize the available data regarding the role of epigenetic modifications on other programmed cell death modes, such as ferroptosis, necroptosis, and parthanatos in cancer and discuss current advancements.
Assuntos
Apoptose , Neoplasias , Humanos , Apoptose/genética , Epigênese Genética , Morte Celular/genética , Neoplasias/patologia , Metilação de DNARESUMO
Farnesol is a non-cyclic sesquiterpene (isoprenoid) found in the essential oils of many plants. In cancer biology, farnesylation of mutated Ras oncoproteins allows the proteins to dock to the membrane and be functionalized. Therefore, farnesyltransferase is a target for drug development to inhibit Ras. Farnesol exhibits cytotoxic activity against tumor cells in vitro and in vivo, implying that novel treatment strategies may be devised independent of Ras farnesylation. Tumors frequently develop resistance towards standard chemotherapies, and thus novel agents are urgently required that bypass the cross-resistance evoked by established anticancer drugs. We investigated whether classical mechanisms of drug resistance such as ATP-binding cassette transporters (P-glycoprotein/MDR1, MRP1, BCRP), the tumor suppressor gene TP53, and the oncogene EGFR play a role in the response of tumor cells to farnesol. Remarkably, none of these genes conferred resistance to farnesol, indicating that this compound may be useful for the treatment of otherwise drug-resistant and refractory tumors expressing these mechanisms of resistance. Furthermore, we applied a pharmacogenomic approach to explore molecular determinants of sensitivity and resistance to farnesol. Among the candidates were genes involved in apoptosis (STAB2, NUMBL), regulation of transcription (CDYL, FOXA2) and diverse other functional groups (INE1, CTRL, MRS2, NEB, LMO7, C9orf3, EHBP1). The fact that these genes are not associated with resistance to traditional anticancer drugs suggests farnesol may possess a novel mechanism of action, and consequently might bypass drug resistance to established chemotherapeutics.
Assuntos
Farneseno Álcool/farmacologia , Neoplasias/tratamento farmacológico , Transportadores de Cassetes de Ligação de ATP/metabolismo , Antibióticos Antineoplásicos/farmacologia , Divisão Celular , Linhagem Celular Tumoral , Análise por Conglomerados , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Genes erbB-1/genética , Genes p53/genética , Células HL-60 , Humanos , Análise em Microsséries , Neoplasias/patologia , Oxazinas/farmacologia , RNA Mensageiro/biossíntese , Transfecção , Xantenos/farmacologiaRESUMO
In the present review, we focus on the importance of blood serum factors for tumor growth in vivo. Data from mice experiments indicate the existence of serum factors, which increase the mitotic index of Ehrlich carcinoma cells from 15 to 80%. The impaired production of these factors increases the life span of tumor-bearing animals from 14-20 days to 90 days. Blocking the production of tumor-specific factors causes the complete regression of already developed Ehrlich carcinoma. These serum factors do not affect the malignant carcinoma cells in vitro. We identified serpins as tumor-specific serum factors. Experimental evidence suggests that serpins are not only essential for tumor growth. Serpins are also involved in the regeneration of normal tissues, such - as adipose tissue, recurrence after cosmetic operations (liposuction), inhibiting rejection after liver transplantation, protection of parasitic flat worms living in host tissues and organs etc. We conclude that the inhibition ofserum factors may represent attractive novel strategies for the prevention and treatment of relapsed cancers.
Assuntos
Carcinoma de Ehrlich/sangue , Serpinas/sangue , Tecido Adiposo/fisiologia , Animais , Carcinoma de Ehrlich/patologia , Proliferação de Células , Humanos , Regeneração , Serpinas/metabolismoRESUMO
BACKGROUND: Every year there are several hundred thousand new cases of oral cancer worldwide. Clinical oncology is still challenged by toxicity and side effects of multimodal therapy strategies in which is associated with poor prognosis for patients. There is an urgent necessity to develop novel therapy strategies. As the majority of anticancer drugs are of natural origin, natural products represent a valuable source for the identification and development of novel treatment options for cancer. The aim of this investigation was to study the cytotoxicity of Salvia officinalis L. (sage) essential oil. METHODS: Salvia officinalis essential oil was gained by aqueous extraction from plant material and subsequently analyzed by gas chromatography. The cytotoxicity of the essential oil on the squamous human cell carcinoma cell line of the oral cavity (UMSCC1) was assessed with the XTT assay. These experiments revealed the half maximal inhibitory concentration (IC(50)) of the essential oil. It was used in the microarray-based analysis of gene expression of UMSSC1 cells. The results were submitted to a signaling pathway analysis. RESULTS: The main constituents of Salvia officinalis essential oil include the monoterpenes thujone, ß-pinene, and 1,8-cineol. Low concentrations of the essential oil increased vitality of the UMSCC1 cells. Beyond the concentration of the IC(50) of 135 µg/ml, sage essential oil reduced UMSSC1 cells viability to a minimum. In the microarray gene expression analysis, genes involved in cancer, cellular growth and proliferation, cell death, cell morphology, cell cycle, gene expression, and DNA repair were the most prominent. The three most significantly regulated pathways by sage were aryl hydrocarbon receptor signaling, cell cycle (G1/S checkpoint) regulation, and p53 signaling. CONCLUSION: To the best of our knowledge, this study suggests for the first time the ability of Salvia officinalis essential oil to inhibit human HNSCC cell growth. The therapeutic potential of sage essential oil might exceed that of its common use in otorhinolaryngology.
Assuntos
Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/fisiopatologia , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/fisiopatologia , Óleos Voláteis/administração & dosagem , Extratos Vegetais/administração & dosagem , Salvia officinalis/química , Antineoplásicos Fitogênicos/administração & dosagem , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pulmonares/patologia , Resultado do TratamentoRESUMO
Lipid rafts are involved in the life cycle of many viruses. In this study, we investigated the role of lipids in the life cycle of vesicular stomatitis virus (VSV). Cholesterol depletion by pretreatment of BHK cells or VSV particles with methyl-beta-cyclodextrin (MbetaCD), a cholesterol-sequestering drug, inhibited the production of VSV dramatically. This effect was reversible, and virus production was restored by the addition of cholesterol, indicating that the reduction was caused by the loss of cholesterol in the cell membrane and virus, respectively. Cholesterol depletion at the adsorption stage also reduced the production of VSV significantly, but in contrast, only had a limited effect on virus production at the post-entry stage. Inhibition of sphingomyelin by myriocin treatment only showed a minor effect on VSV production. However, reduction of cholesterol and sphingomyelin at the same time dramatically reduced VSV production, showed a significant synergistic effect. These results suggest that lipid rafts play an important role in the life cycle of VSV.
Assuntos
Microdomínios da Membrana/virologia , Vesiculovirus/fisiologia , Internalização do Vírus , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colesterol/metabolismo , Cricetinae , Ácidos Graxos Monoinsaturados/metabolismo , Ácidos Graxos Monoinsaturados/toxicidade , Esfingomielinas/metabolismo , beta-Ciclodextrinas/metabolismo , beta-Ciclodextrinas/toxicidadeRESUMO
Multidrug resistance (MDR) is still a major threat to successful clinical application of cancer chemotherapy. Copper plays an important role in biological systems, and copper is also involved in carcinogenesis. In the present investigation, we addressed the question whether metal copper might be involved in drug resistance of murine and human tumors. By means of atomic absorption spectroscopy, we determined serum copper concentrations. We found that the blood serum of tumor-bearing mice contained higher amounts of copper than healthy mice with tumors. Secondly, mice bearing doxorubicin-resistant Ehrlich ascites carcinoma- or cyclophosphamide-resistant Lewis lung carcinoma contained more copper in their serum than mice bearing the corresponding drug-sensitive parental tumors. Furthermore, the analysis of patients with breast cancer, colon carcinoma or lung cancer showed that the serum copper contents were higher in patients not responding to chemotherapy when compared to patients whose tumors responded to treatment. The copper levels in serum of healthy volunteers were lower than in cancer patients irrespective of their response to chemotherapy. Our results imply that the level of serum copper may be considered as a biomarker for treatment response.
Assuntos
Cobre/química , Resistencia a Medicamentos Antineoplásicos , Neoplasias/tratamento farmacológico , Adulto , Idoso , Animais , Linhagem Celular Tumoral , Cobre/sangue , Cobre/fisiologia , Resistência a Múltiplos Medicamentos , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Transplante de NeoplasiasRESUMO
Glutathione (GSH), an important component of the phase II detoxification system, plays a major role in storage, metabolism and transport of metals across the cell membrane. The role of copper, its metabolism and storage in living systems is not completely understood. Copper plays an important role in a number of physiological processes, e.g. several growth and transcription factors require copper for activity. In the present investigation, we focused on copper (II) (N-2-hydroxyacetophenone) glycinate (CuNG), a novel in vitro and in vivo resistance modifying agent. A conjugate of GSH and CuNG was detected in vivo in mice and was characterized by spectroscopic studies. Based on UV, IR, proton NMR and elemental analyses, the chemical structure of the conjugate was elucidated. By means of atomic absorption data, the distribution and metabolism of CuNG is described.
Assuntos
Cobre/metabolismo , Glutationa/metabolismo , Animais , Cromatografia Líquida , Cobre/química , Glutationa/química , Masculino , Camundongos , Modelos Moleculares , Análise Espectral/métodosRESUMO
In the present study, we analyzed differential composition of blood serum from Ehrlich carcinoma-bearing and healthy male C57Bl/6 mice by isolating complexes of hemoglobin and other serum proteins by a proteomic approach (gel filtration, gel electrophoresis, and mass spectrometry). The hemoglobin fractions isolated from the serum of mice- bearing tumors contained several proteins with molecular weights of 15, 65, 68, and 100 kDa, while hemoglobin fractions isolated from the serum of healthy mice did not contain additional protein bands. These bands were identified by MALDI-TOF as haptoglobin, serum albumin, a homologue of alpha-fetoprotein, and hemoglobin-alpha. Ion exchange chromatography indicated complex formation of these proteins. Injection of hemoglobin-associated blood serum proteins (HAP) isolated from tumor-bearing animals, leads to tumor regression. Intraperitoneally injected HAP-induced apoptosis in Ehrlich carcinoma cells but not normal peritoneal cells and led to a complete regression of the ascitic or solid Ehrlich carcinoma. A one-year follow up of the animals did not reveal any signs of tumor growth. In conclusion, HAP might be a novel principle of tumor regression. The clinical relevance of these findings with Ehrlich carcinoma should be investigated in the future.
Assuntos
Proteínas Sanguíneas/isolamento & purificação , Carcinoma de Ehrlich/sangue , Hemoglobinas/isolamento & purificação , Sequência de Aminoácidos , Animais , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por MatrizRESUMO
Multiple drug resistance (MDR) represents a major obstacle to successful application of chemotherapy and a basic problem in cancer biology. MDR occurs at the cellular level and is multi-factorial in nature. The multidrug resistance gene, MDR1, and its gene product P-glycoprotein (P-gp) are now well known as an important determinant of MDR. Much effort has been devoted to develop P-gp inhibitors to modulate resistance. However, most of these resistance-modifying agents (RMA) are too toxic at the required doses. Therefore, the development of novel RMAs to overcome MDR represents a major challenge to modern cancer chemotherapy. In the present investigation, we describe the effect of oxalyl bis (N-phenyl) hydroxamic acid (OBPHA) and copper N-(2-hydroxy acetophenone) glycinate (CuNG) on multidrug-resistant P-gp-expressing CEM/ADR5000 T-cell acute lymphoblastic leukemia cells. CuNG, a known depleting agent for glutathione (GSH) and inhibitor of glutathione S-transferase (GST) and multidrug resistance-related protein 1 (MRP1), also inhibited P-gp-mediated doxorubicin accumulation and retention. The resistance-modifying effects of OBPHA were stronger than that of CuNG. Both novel RMAs overcame drug resistance more efficiently than verapamil, a well-known P-gp inhibitor. OBPHA and CuNG exposure resulted in an increased doxorubicin accumulation after 1-3h incubation by down-regulation of P-gp expression after 24h incubation. This is a clue that different mechanisms may contribute to modulation of P-gp-mediated drug resistance by these compounds.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Benzenoacetamidas/farmacologia , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Glicina/análogos & derivados , Ácidos Hidroxâmicos/farmacologia , Leucemia-Linfoma de Células T do Adulto/tratamento farmacológico , Compostos Organometálicos/farmacologia , Oxalatos/farmacologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Antibióticos Antineoplásicos/farmacologia , Bloqueadores dos Canais de Cálcio/farmacologia , Doxorrubicina/farmacologia , Glicina/farmacologia , Humanos , Leucemia-Linfoma de Células T do Adulto/metabolismo , Células Tumorais Cultivadas , Verapamil/farmacologiaRESUMO
To evaluate the prognostic significance of cytogenetic findings in clear cell renal cell carcinoma (RCC), cytogenetic results of 118 primary RCCs were evaluated in relation to classical indicators of prognosis and overall survival. Losses in 3p (98.3%) were most prevalent and included 32 (27.6%) monosomies of chromosome 3 and 84 (72.4%) structural aberrations involving 3p, of which 36 were unbalanced translocations, der(3)t(3;5)(p11-p22;q13-q31), resulting in duplication of 5q sequences. Patients with gain of 5q31-qter resulting from either polysomies or structural rearrangements of 5q, the most frequent of which was der(3)t(3;5), had a significantly better outcome than those without this aberration (P = 0.001). There was no association between gain of 5q or der(3)t(3;5) and any of the well-known variables for prognosis, including low versus high clinical stage and grade of malignancy. Among additional chromosomal aberrations, loss of chromosome 9/9p was associated with distant metastasis at diagnosis (P = 0.006). The data indicate that gain of 5q identifies a clinically favorable cytogenetic variant of clear cell RCC and demonstrate the impact of specific chromosome aberrations as additional prognostic indicators in clear cell RCC.
Assuntos
Adenocarcinoma de Células Claras/genética , Carcinoma de Células Renais/genética , Aberrações Cromossômicas , Cromossomos Humanos Par 5 , Neoplasias Renais/genética , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Renais/patologia , Feminino , Seguimentos , Humanos , Cariotipagem , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Taxa de SobrevidaRESUMO
ETHNOPHARMACOLOGIC RELEVANCE: Artemisia judaica L. (Arabic name: Beithran), is a medicinal and aromatic plant growing in the valley bottoms of desert areas, particularly in the southern desert of Jordan nearest to the Jordan-Saudi Arabia borders and in Wadi Araba in the Southern Badia. In Jordan, A. judaica is widely used in traditional medicine being recommended by aboriginal Bedouins in the North Badia region of Jordan as calmative. Furthermore, it is used for the treatment of stomach ache, heart diseases, sexual weakness, diabetes, gastro-intestinal disorders and external wounding. Additionally, other folk medicines of the Arabic region commonly use this aromatic plant for the treatment of inflammatory-related diseases, for instance fungal infections, diabetes, atherosclerosis, cancer and arthritis. AIM OF THE STUDY: Considering the traditional medicinal uses and the lack of scientific studies addressing the cellular and molecular mechanisms behind A. judaica claimed activities, the present study was designed to validate some of the traditional uses ascribed to this species, specifically the antifungal and anti-inflammatory activities of A. judaica essential oil at doses devoid of cytotoxicity to mammalian cells. MATERIALS AND METHODS: Chemical analysis of A. judaica essential oil isolated by hydrodistillation from aerial parts was carried out by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antifungal activity (minimal inhibitory concentrations and minimal lethal concentrations) was evaluated against yeasts, dermatophyte and Aspergillus strains. In order to deeply explore the mechanisms behind the anti-fungal effect of the essential oil, the germ tube inhibition assay and the biofilms formation assay were evaluated using Candida albicans. The assessment of cell viability was accomplished using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay in both hepatocytes and macrophages. Furthermore, the in vitro anti-inflammatory potential of A. judaica oil was evaluated by measuring nitric oxide (NO) production using lipopolysaccharide (LPS)-stimulated mouse macrophages. RESULTS: Oxygen containing monoterpenes are a representative group of constituents (68.7%) with piperitone (30.4%), camphor (16.1%) and ethyl cinnamate (11.0%) as main compounds. The highest antifungal activity of the oil was observed against Cryptococcus neoformans, with a MIC value of 0.16µL/mL. The oil revealed an important inhibitory effect on germ tube formation in C. albicans with 80% inhibition of filamentation at a concentration of 0.16µL/mL. Importantly, the oil also interfered with pre-formed biofilms by reducing the amount of the attached biomass. Furthermore, the essential oil significantly inhibited NO production evoked by LPS on macrophages at concentrations with very low toxicity (0.32µL/mL) or without toxicity (0.16µL/mL) to both macrophages and hepatocytes. CONCLUSIONS: The present study revealed that A. judaica essential oil from Jordan significantly inhibited germ tube formation and disrupted preformed biofilms of C. albicans, emphasizing the therapeutic potential for the treatment of disseminated candidiasis. Additionally, safe concentrations of this essential oil significantly inhibited NO production elicited by LPS in macrophages, highlighting its potential anti-inflammatory activity. Overall, A. judaica bears promising therapeutic potential for further drug development. Importantly, this work also validates some of the traditional uses of A. judaica.
Assuntos
Anti-Inflamatórios/farmacologia , Antifúngicos/farmacologia , Artemisia/química , Candida albicans/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Óleos de Plantas/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/toxicidade , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/toxicidade , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Candida albicans/crescimento & desenvolvimento , Sobrevivência Celular/efeitos dos fármacos , Cryptococcus neoformans/crescimento & desenvolvimento , Clima Desértico , Relação Dose-Resposta a Droga , Cromatografia Gasosa-Espectrometria de Massas , Células Hep G2 , Humanos , Jordânia , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Óxido Nítrico/metabolismo , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Óleos Voláteis/toxicidade , Fitoterapia , Componentes Aéreos da Planta/química , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Óleos de Plantas/química , Óleos de Plantas/isolamento & purificação , Óleos de Plantas/toxicidade , Plantas Medicinais , Células RAW 264.7RESUMO
ETHNOPHARMACOLOGIC RELEVANCE: Ziziphora tenuior L. (Lamiaceae) is a medicinal plant in Jordan, which is included in various antimicrobial, antiseptic, expectorant and wound healing preparations. It is used for the treatment of cough, stomach ache, dysentery, fever, uterus infection, gut inflammation and painful menstruation. AIM OF THE STUDY: The aim of this study was to assess, for the first time, the chemical composition of the essential oil of Z. tenuior originated from southern Jordan and its antifungal effects against several yeasts. Concomitantly, the mechanisms behind the anti-fungal activity against Candida albicans were also disclosed. Since the Z. tenuior traditional uses are related with inflammatory-associated conditions, the putative anti-inflammatory activity of the oil was also unveiled. Importantly, the potential toxicity of pharmacologically active concentrations was screened in different types of mammalian cells. MATERIALS AND METHODS: Z. tenuior essential oil, isolated by hydrodistillation, was analyzed by gas chromatography, gas chromatography-mass spectrometry and 13C nuclear magnetic resonance spectroscopy. Antifungal activity was evaluated against yeasts, dermatophytes and Aspergillus strains. Germ tube inhibition and biofilm formation assays were evaluated using C. albicans. Assessment of cell viability was made by the MTT assay using different types of mammalian cells, including hepatocytes, keratinocytes and macrophages. The in vitro anti-inflammatory potential of the oil was evaluated by measuring nitric oxide production using lipopolysaccharide-stimulated mouse macrophages. RESULTS: Oxygen-containing monoterpenes are the main oil compounds: pulegone (46.8%), p-menth-3-en-8-ol (12.5%), isomenthone (6.6%) and 8-hydroxymenthone (6.2%). The highest antifungal activity was against Cryptococcus neoformans, with a MIC value of 0.16µL/mL. The oil revealed an important inhibitory effect on germ tube formation with a filamentation inhibition rate higher than 80% at 0.16µL/mL. The amount of the attached biomass was reduced. Importantly, concentrations devoid of toxicity on several mammalian cell types still displayed anti-inflammatory activity (0.16 and 0.32µL/mL). CONCLUSIONS: These findings add significant information to the pharmacological activity of Z. tenuior, thus justifying and reinforcing the use of this plant in traditional medicine. Additionally, the antifungal and anti-inflammatory potential of the oil at non-toxic concentrations, opens new avenues for its further exploitation, for instance in health-care product development.
Assuntos
Lamiaceae/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Biomassa , Candida albicans/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Cryptococcus neoformans/efeitos dos fármacos , Monoterpenos Cicloexânicos , Células Hep G2 , Humanos , Jordânia , Macrófagos/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana/métodos , Monoterpenos/química , Monoterpenos/farmacologia , Óleos Voláteis/química , Óleos de Plantas/química , Terpenos/química , Terpenos/farmacologiaRESUMO
So far, the problem of an influence of translocations on the telomeres of the involved chromosomes has not been addressed yet in human cells. Therefore, the telomeres of a karyotypically rather well characterized T-cell acute lymphoblastic leukemia (T-ALL) cell line (CCRF-CEM) with several marker chromosomes were examined using peptide nucleic acid (PNA) telomere FISH probes to compare the telomere length of these markers with that of the chromosome arms of their origin. In addition, chromosome libraries, centromeric probes, and subtelomeric DNA probes were used to further define the marker chromosomes. Two markers could be newly defined and a concise karyotype of the cell line could be obtained by these detailed examinations: 42-47,X,-X,del(5) (q35?),t(5;15)(q14;q13.2),t(8;9)(p11;p24),del(9)(:p13-->qter)/inv(9)(pter-->p12::q21-->p12::q21-->qter),+13,+20,+der(22)(p+ [HSR?])[cp]. The relative telomere length of all chromosomes showed considerable interchromosomal, intercellular, and inter-passage variation. However, it could be shown, that in four different passages of the examined cell line the observed differences between relative telomere lengths of the markers and the chromosomes of their origin, with two exceptions (short arms of del/inv9 and der22), were not significant. On the other hand, because of its mentioned variability, telomere length alone is not sufficient to reliably define the derivation of markers.
Assuntos
Leucemia-Linfoma de Células T do Adulto/genética , Telômero/genética , Linhagem Celular Tumoral , Aberrações Cromossômicas , Mapeamento Cromossômico , Marcadores Genéticos , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Telômero/ultraestruturaRESUMO
The detection of multidrug resistance (MDR) in clinical hospital practice represents an important strategy to combat clinical tumor drug resistance. Predicting the response of tumors to cytostatic drugs is of prognostic value. The 'Debate Round-Table on Phenotypic and Genotypic Analyses of Multidrug Resistance (MDR) in Clinical Hospital Practice' was launched in 1997 to address specific questions on this topic. The results published thus far are a rich source to learn about the promises and pitfalls of methods, eg surrogate and functional tests and protein or mRNA expression assays as well. In the present paper, some requirements are discussed for applications of drug resistance testing in clinical routine diagnostics. To improve the detection of low-level resistance, established methodologies may be strengthened with respect to: (1) standardization of sample handling, antibodies, PCR primers, and detection reagents; (2) standardization of protocols and far reaching automation in performance and evaluation of results to ensure high quality control criteria. Sophisticated new techniques will feature: (1) high-throughput analyses for the 'horizontal screening' of single drug resistance genes in large numbers of patient samples at economically fair costs; (2) 'vertical screening' of a large number of resistance mechanisms operating upstream or downstream of the actual drug-target interaction sites, in order to detect more complex and multifaceted genotypes and phenotypes of multidrug resistance.
Assuntos
Resistência a Múltiplos Medicamentos/genética , Resistencia a Medicamentos Antineoplásicos/genética , Reação em Cadeia da Polimerase , Genótipo , Hospitais , Humanos , FenótipoRESUMO
We compared test methods based on specific mechanisms of daunorubicin (DNR) resistance to more global procedures. Assessment of P-glycoprotein (P-gp) expression and function by means of immunocytochemistry, DNR accumulation, and modulation of resistance and accumulation by the P-gp inhibitor cyclosporin A (CsA) were selected as parameters for multidrug resistance (MDR). On the other hand, we used the MTT assay and measured apoptosis and proliferative activity (S- and G2M-phases of the cell cycle) by flow cytometry. Validation of test methods was achieved for four leukemic cell lines (HL-60, KG-1a, K562/WT, K562/ADM). This battery of tests was then applied to mononuclear cells (MNC) from 18 leukemic patients. Low proficiency of MNC to undergo apoptosis and low proliferative activity rather than P-gp-mediated MDR correlated with DNR resistance as measured by the MTT assay. Bell-shaped dose-response curves for apoptosis, however, which reflect a switch from the apoptotic to the necrotic death mode with increasing cellular damage tend to limit practicability in clinical testing, because appropriate dose range and time points need to be explored. Thus, measurement of apoptosis by flow cytometry may be less convenient than the MTT assay for determination of chemosensitivity, if clinical samples with unknown patterns of responsiveness are to be tested. Spontaneous apoptosis in untreated MNC following 24 h incubation in vitro correlated significantly with DNR sensitivity in the MTT assay. A lack of essential viability factors (eg growth factors or cytokines) in vitro which are known to prevent apoptosis may contribute to DNR sensitivity.
Assuntos
Antibióticos Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Daunorrubicina/farmacologia , Leucemia/tratamento farmacológico , Resistência a Medicamentos , Humanos , Leucemia/patologia , Sais de Tetrazólio/metabolismo , Tiazóis/metabolismo , Células Tumorais CultivadasRESUMO
Glucose-6-phosphate dehydrogenase (G6PD) deficiency belongs to the most common human disorders of metabolism. In affected patients generation of free radicals causes life-threatening hemolytic crises, for example, after consumption of certain drugs and foods or after infections. Rather than erythrocytes we analyzed mononuclear white blood cells of a patient suffering from G6PD deficiency with respect to their ability to enter apoptosis after treatment with daunorubicin, ionizing radiation, or dexamethasone. The induction of apoptosis was increased in G6PD-deficient cells compared to cells from eight normal donors. In parallel, the glutathione content of mononuclear cells from the G6PD-deficient patient was significantly decreased. While in affected patients decreased life span of erythrocytes damaged by oxidative stress has long been recognized as the mechanism underlying hemolysis, peripheral leukocytes have not received similar attention. Induction of apoptosis is a relatively complex process that has been linked to cellular glutathione content. This is the first report investigating G6PD deficiency and apoptosis.
Assuntos
Apoptose , Deficiência de Glucosefosfato Desidrogenase/sangue , Leucócitos Mononucleares/fisiologia , Adulto , DNA/sangue , Daunorrubicina/farmacologia , Dexametasona/farmacologia , Citometria de Fluxo , Glutationa/sangue , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/efeitos da radiação , Radiação IonizanteRESUMO
Patients affected with X chromosome-linked, hereditary glucose-6-phosphate dehydrogenase (G6PD) deficiency suffer from life-threatening hemolytic crises after intake of certain drugs or foods. G6PD deficiency is associated with low levels of reduced glutathione. We analyzed mononuclear white blood cells (MNC) of three males suffering from the German G6PD Aachen variant, four heterozygote females of this family, one G6PD-deficient male from another family coming from Iran, and six healthy male volunteers with respect to their DNA damage in two different genes (G6PD and T-cell receptor-delta) and their propensity to enter apoptosis after UV illumination (0.08-5.28 J/cm2). As determined by PCR stop assays, there was more UV-induced DNA damage in MNC of G6PD-deficient male patients than in those of healthy subjects. MNC of G6PD-deficient patients showed a higher rate of apoptosis after UV irradiation than MNC of healthy donors. MNC of heterozygote females showed intermediate rates of DNA damage and apoptosis. It is concluded that increased DNA damage may be a result of deficient detoxification of reactive oxygen species by glutathione and may ultimately account for the higher rate of apoptosis in G6PD-deficient MNC.
Assuntos
Apoptose/efeitos da radiação , Dano ao DNA , Deficiência de Glucosefosfato Desidrogenase/sangue , Leucócitos Mononucleares/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Adolescente , Adulto , Idoso , DNA/efeitos da radiação , Feminino , Genes Codificadores da Cadeia delta de Receptores de Linfócitos T/genética , Genes Codificadores da Cadeia delta de Receptores de Linfócitos T/efeitos da radiação , Variação Genética , Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/patologia , Glutationa/sangue , Heterozigoto , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Leucócitos Mononucleares/fisiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da PolimeraseRESUMO
ATP-binding cassette (ABC) transporter genes are ubiquitously present in most organisms from bacteria to man. This gene family is the largest one known as of yet. Still growing, the number of human ABC transporters counts currently 47 members which belong to seven subfamilies. ABC transporters share a similar molecular architecture: (1) Full-structured transporters harbor two symmetric halves each consisting of one nucleotide binding domain (NBD) and one transmembrane domain (TMD). (2) Half-transporters with one NBD and one TMD homo- or heterodimerize to functional transporter complexes. ABC transporters are "traffic ATPases" which hydrolyze ATP and which transport a wide array of molecules or conduct the transport of molecules by stimulating other translocation mechanisms. Many ABC transporters are involved in human inherited or sporadic diseases such as cystic fibrosis, adrenoleukodystrophy, Stargardt's disease, drug-resistant tumors, Dubin-Johnson syndrome, Byler's disease, progressive familiar intrahepatic cholestasis, X-linked sideroblastic anemia and ataxia, persistent hyperinsulimenic hypoglycemia of infancy, and others. The present review summarizes the current findings in basic research and the efforts for bridging the gap to clinical applications in therapy and diagnostics.
Assuntos
Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Transporte Biológico , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/química , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Transportadores de Cassetes de Ligação de ATP/química , Transportadores de Cassetes de Ligação de ATP/classificação , Adrenoleucodistrofia/terapia , Animais , Fibrose Cística/terapia , Terapia Genética/métodos , HumanosRESUMO
Cancer is a leading cause of mortality and the annual incidence of new cancer cases is rising worldwide. Due to the frequent development of resistance and the side effects of established anti-cancer drugs, the quest for new drugs with improved therapeutic features goes on. In contrast to cytotoxic chemotherapy of the past, the concept of targeted chemotherapy attempts to increase specificity of therapy by attacking tumor-related mechanisms. A novel emerging treatment concept represents the inhibition of centrosomal clustering. The centrosome regulates mitotic spindle formation assuring uniform separation of chromosomes to daughter cells. Many tumors contain supernumerary centrosomes, which contribute to aneuploidy induction via multipolar mitotic spindle formation. As spindle multipolarity leads to cell death, tumor cells developed centrosomal clustering mechanism to prevent multipolar spindle formation by coalescence of multiple centrosomes into two functional spindle poles. Inhibition of centrosome clustering represents a novel strategy for drug development and leads to the formation of multipolar spindles and subsequent cell death. In the present review, we report advances in understanding the biology of centrosomal clustering as well as enlist compounds capable of inducing the formation of multipolar spindles such as indolquinolizines, integrin-linked kinase inhibitors (QLT-0267), noscapinoids (EM011), phthalamide derivatives (TC11), griseofulvin, phenanthridines (PJ-34), CCC1-01, CW069 GF-15, colcemid, nocodazole, paclitaxel, and vinblastine. We also present in silico result of compounds that bind to γ-tubulin under the ambit of centrosomal clustering inhibition. We observed maximum binding efficacy in GF-15, CW069, paclitaxel and larotaxel with GF-15 exhibiting least energy of -8.4 Kcal/mol and 0.7 µM Pki value.
Assuntos
Centrossomo/patologia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Animais , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Centrossomo/efeitos dos fármacos , HumanosRESUMO
ETHNOPHARMACOLOGIC RELEVANCE: Artemisia herba-alba Asso ("desert wormwood" in English; "armoise blanche" in French; "shaih" in Arabic), is a medicinal and strongly aromatic plant widely used in traditional medicine by many cultures since ancient times. It is used to treat inflammatory disorders (colds, coughing, bronchitis, diarrhea), infectious diseases (skin diseases, scabies, syphilis) and others (diabetes, neuralgias). In Jordanian traditional medicine, this plant is used as antiseptic and against skin diseases, scabies, syphilis, fever as well as menstrual and nervous disorders. AIM OF THE STUDY: Considering the traditional medicinal uses and the lack of scientific studies addressing the cellular and molecular players involved in these biological activities, the present study was designed to unveil the antifungal and anti-inflammatory activities of A. herba-alba Asso essential oil at doses devoid of toxicity to mammalian cells. MATERIALS AND METHODS: Chemical analysis of A. herba-alba essential oil isolated by hydrodistillation from aerial parts was carried out by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The antifungal activity (minimal inhibitory concentrations and minimal lethal concentrations) was evaluated against yeasts, dermatophyte and Aspergillus strains. In order to explore the mechanisms behind the anti-fungal effect of the essential oil, the germ tube inhibition assay was evaluated using Candida albicans. The assessment of cell viability was accomplished using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and the in vitro anti-inflammatory potential of A. herba-alba oil at the periphery and central nervous system was evaluated by measuring nitric oxide (NO) production using lipopolysaccharide (LPS)-stimulated mouse macrophages and microglia, respectively. RESULTS: Oxygen-containing monoterpenes are the main compounds of the oil, namely 1,8-cineole (20.1%), ß-thujone (25.1%), α-thujone (22.9%) and camphor (10.5%). Among the fungal strains tested, the oil demonstrated potential against Trichophyton rubrum and Epidermophyton floccosum, with minimal inhibitory concentration (MIC) and minimal lethal concentration (MCL) values of 0.32 mg/mL and Cryptococcus neoformans with MIC of 0.64 mg/mL. The oil revealed a strong inhibitory effect on germ tube formation in C. albicans with inhibition of filamentation around 90% at a concentration 0.16 mg/mL. Importantly, the essential oil significantly inhibited NO production evoked by LPS without cytotoxicity at concentrations up to 1.25 µL/mL in macrophages and up to 0.32 µL/mL in microglia. Furthermore, evaluation of cell viability in RAW 264.7 macrophages, BW2 microgliacells and HaCaT keratinocytes showed no cytotoxicity at concentrations up to 0.32 µL/mL. CONCLUSIONS: It was possible to find appropriate doses of A. herba-alba oil with both antifungal and anti-inflammatory activities and without detrimental effects towards several mammalian cell types. These findings add significant information to the pharmacological activity of A. herba-alba essential oil, specifically to its antifungal and anti-inflammatory therapeutic value, thus justifying and reinforcing the use of this plant in traditional medicine.