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1.
Int J Mol Sci ; 25(10)2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38791506

RESUMO

Breast cancer, the most invasive cancer in women globally, necessitates novel treatments due to prevailing limitations of therapeutics. Search of news anticancer targets is more necessary than ever to tackle this pathology. Heat-Shock Protein 90 (HSP90), a chaperone protein, is implicated in breast cancer pathogenesis, rendering it an appealing target. Looking for alternative approach such as Plant-based compounds and natural HSP90 inhibitors offer promising prospects for innovative therapeutic strategies. This study aims to identify plant-based compounds with anticancer effects on breast cancer models and elucidate their mechanism of action in inhibiting the HSP90 protein. A systematic review was conducted and completed in January 2024 and included in vitro, in vivo, and in silico studies that investigated the effectiveness of plant-based HSP90 inhibitors tested on breast cancer models. Eleven studies were included in the review. Six plants and 24 compounds from six different classes were identified and proved to be effective against HSP90 in breast cancer models. The studied plant extracts showed a dose- and time-dependent decrease in cell viability. Variable IC50 values showed antiproliferative effects, with the plant Tubocapsicum anomalum demonstrating the lowest value. Withanolides was the most studied class. Fennel, Trianthema portulacastrum, and Spatholobus suberectus extracts were shown to inhibit tumor growth and angiogenesis and modulate HSP90 expression as well as its cochaperone interactions in breast cancer mouse models. The identified plant extracts and compounds were proven effective against HSP90 in breast cancer models, and this inhibition showed promising effects on breast cancer biology. Collectively, these results urge the need of further studies to better understand the mechanism of action of HSP90 inhibitors using comparable methods for preclinical observations.


Assuntos
Neoplasias da Mama , Proteínas de Choque Térmico HSP90 , Animais , Feminino , Humanos , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/metabolismo , Extratos Vegetais/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia
2.
BMC Cancer ; 22(1): 1142, 2022 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-36344948

RESUMO

BACKGROUND: Our review discuss (i) the findings from analyzed data that have examined KRAS, NRAS and BRAF mutations in patients with colorectal cancer (CRC) in North Africa and to compare its prevalence with that shown in other populations and (ii) the possible role of dietary and lifestyle factors with CRC risk.  METHODS: Using electronic databases, a systematic literature search was performed for the KRAS, NRAS, and BRAF mutations in CRC patients from Morocco, Tunisia, Algeria and Lybia.  RESULTS: Seventeen studies were identified through electronic searches with six studies conducted in Morocco, eight in Tunisia, two in Algeria, and one in Libya. A total of 1843 CRC patients were included 576 (31.3%) in Morocco, 641 (34.8%) in Tunisia, 592 (32.1%) in Algeria, and 34 (1.8%) in Libya. Overall, the average age of patients was 52.7 years old. Patients were predominantly male (56.6%). The mutation rates of KRAS, NRAS and BRAF were 46.4%, 3.2% and 3.5% of all patients, respectively. A broad range of reported KRAS mutation frequencies have been reported in North Africa countries. The KRAS mutation frequency was 23.9% to 51% in Morocco, 23.1% to 68.2% in Tunisia, 31.4% to 50% in Algeria, and 38.2% in Libya. The G12D was the most frequently identified KRAS exon 2 mutations (31.6%), followed by G12V (25.4%), G13D (15.5%), G12C (10.2%), G12A (6.9%), and G12S (6.4%). G12R, G13V, G13C and G13R are less than 5%. There are important differences among North Africa countries. In Morocco and Tunisia, there is a higher prevalence of G12D mutation in KRAS exon 2 (≈50%). The most frequently mutation type in KRAS exon 3 was Q61L (40%). A59T and Q61E mutations were also found. In KRAS exon 4, the most common mutation was A146T (50%), followed by K117N (33.3%), A146P (8.3%) and A146V (8.3%). CONCLUSION: KRAS mutated CRC patients in North Africa have been identified with incidence closer to the European figures. Beside established anti-CRC treatment, better understanding of the causality of CRC can be established by combining epidemiology and genetic/epigenetic on CRC etiology. This approach may be able to significantly reduce the burden of CRC in North Africa.


Assuntos
Neoplasias Colorretais , Proteínas Proto-Oncogênicas B-raf , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/genética , Prevalência , Mutação , Sistema de Sinalização das MAP Quinases , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Tunísia/epidemiologia
3.
BMC Infect Dis ; 18(1): 680, 2018 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-30567502

RESUMO

BACKGROUND: The widespread use of an effective and safe vaccine to measles has substantially decreased morbidity and mortality from this epidemic. Nevertheless, HIV-infected children vaccinated against measles may develop an impaired vaccine response and remain susceptible to this disease. In Morocco, infants are routinely vaccinated against measles, regardless of their HIV serostatus. An evaluation of the immunization of these children may be of paramount importance to implement timely measures aimed at preventing measles transmission. METHODS: In this study, we have enrolled 114 children vaccinated against measles, 50 children prenatally infected with HIV and 64 HIV-uninfected children. For all children, blood samples were taken to measure anti-measles IgG by EIA and CD4 count by flow cytometry. Additionally, HIV viral load was determined by automated real time PCR, for HIV-infected children. RESULTS: The seroprotective rate of IgG anti-measles antibodies was significantly lower among HIV-infected children (26%) compared with HIV-uninfected children (73%) (p < 0.001). Within HIV-infected children group, the comparison of variables between children without seroprotective seroconversion to measles and those with seroprotective immunity, displayed that sex and age were not statistically different, p > 0.999 and p = 0.730, respectively. However, CD4 count was lower among children with negative serostatus to measles (23% versus 32%, p < 0.001). Furthermore, viral load was higher, with 2.91 log10 ± 2.24 versus 1.7 log10 ± 1.5 (p = 0.042). Finally, 62% of children with a negative vaccine response to measles were under HAART therapy, versus 92% (p = 0.008). CONCLUSION: The majority of HIV-infected children vaccinated against measles develop a suboptimal seroprotective titer, and therefore remain at risk for this highly infectious disease. These data in combination with international recommendations, including recent WHO guidance on vaccination of HIV-infected children, suggest there is a need for national measures to prevent these children from measles.


Assuntos
Anticorpos Antivirais/sangue , Formação de Anticorpos , Infecções por HIV/epidemiologia , Transmissão Vertical de Doenças Infecciosas , Vacina contra Sarampo/uso terapêutico , Sarampo/epidemiologia , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , HIV , Infecções por HIV/sangue , Infecções por HIV/complicações , Infecções por HIV/imunologia , Humanos , Lactente , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Masculino , Sarampo/sangue , Sarampo/complicações , Vacina contra Sarampo/imunologia , Vírus do Sarampo/imunologia , Marrocos/epidemiologia , Estudos Soroepidemiológicos , Vacinação
4.
Enzyme Microb Technol ; 114: 1-6, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29685347

RESUMO

The present work describes a method for detecting the ingress of gas phase oxygen into packed food. It uses the enzyme polyphenol oxidase (PPO)from Mushroom and Mediterranean dwarf palm. The PPO is incorporated into an indubiose film along with a non-toxic polyphenol such as gallic acid or chlorogenic acid. If exposed to oxygen, the test spot undergoes an irreversible and visible color change from pale to deep brown due to the PPO catalyzed oxidation of the respective polyphenol by oxygen. The color change can be detected visually or by spectrophotometry at 470 nm. The effect of the amount of oxygen or substrate, type of enzyme substrate, enzyme source, temperature and duration of storage on the response were studied. Air oxygen can be detected within 30 min under optimized condition. The smallest amount of oxygen that can be detected with acceptable response time (120 min) is 5%. The test is highly selective for oxygen and the detector is stable over time. The detector may be used in any application as long as the presence or absence of oxygen in a sealed space is determined prior to the application using the detector.


Assuntos
Agaricales/enzimologia , Arecaceae/enzimologia , Técnicas Biossensoriais/métodos , Catecol Oxidase/química , Proteínas Fúngicas/química , Oxigênio/análise , Proteínas de Plantas/química , Biocatálise , Técnicas Biossensoriais/instrumentação , Cor , Cinética , Espectrofotometria , Especificidade por Substrato , Temperatura
5.
Nat Commun ; 7: 12203, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27417143

RESUMO

The accumulation of lipid droplets (LD) is frequently observed in hepatitis C virus (HCV) infection and represents an important risk factor for the development of liver steatosis and cirrhosis. The mechanisms of LD biogenesis and growth remain open questions. Here, transcriptome analysis reveals a significant upregulation of septin 9 in HCV-induced cirrhosis compared with the normal liver. HCV infection increases septin 9 expression and induces its assembly into filaments. Septin 9 regulates LD growth and perinuclear accumulation in a manner dependent on dynamic microtubules. The effects of septin 9 on LDs are also dependent on binding to PtdIns5P, which, in turn, controls the formation of septin 9 filaments and its interaction with microtubules. This previously undescribed cooperation between PtdIns5P and septin 9 regulates oleate-induced accumulation of LDs. Overall, our data offer a novel route for LD growth through the involvement of a septin 9/PtdIns5P signalling pathway.


Assuntos
Hepacivirus/patogenicidade , Gotículas Lipídicas/metabolismo , Microtúbulos/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Septinas/metabolismo , Linhagem Celular Tumoral , Regulação da Expressão Gênica , Hepacivirus/fisiologia , Hepatite C/metabolismo , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Gotículas Lipídicas/efeitos dos fármacos , Metabolismo dos Lipídeos/fisiologia , Cirrose Hepática/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/virologia , Microtúbulos/virologia , Ácido Oleico/farmacologia , Septinas/genética , Replicação Viral
6.
Nutr Cancer ; 68(1): 131-43, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26771897

RESUMO

Telomerase is activated in human papillomavirus (HPV) positive cervical cancer and targeting telomeres offers a novel anticancer therapeutic strategy. In this study, the telomere targeting properties, the cytotoxic as well as the pro-apoptotic effects of hexane (IV-HE) and dichloromethane (IV-DF) fractions from Inula viscosa L. extracts were investigated on human cervical HeLa and SiHa cancer cells. Our data demonstrate that IV-HE and IV-DF extracts were able to inhibit cell growth in HeLa and SiHa cells in a dose-dependent manner and studied resistant cell lines exhibited a resistance factor less than 2 when treated with the extracts. IV-HE and IV-DF extracts were able to inhibit telomerase activity and to induce telomere shortening as shown by telomeric repeat amplification protocol and TTAGGG telomere length assay, respectively. The sensitivity of fibroblasts to the extracts was increased when telomerase was expressed. Finally, IV-HE and IV-DF were able to induce apoptosis as evidenced by an increase in annexin-V labeling and caspase-3 activity. This study provides the first evidence that the IV-HE and IV-DF extracts from Inula viscosa L. target telomeres induce apoptosis and overcome drug resistance in tumor cells. Future studies will focus on the identification of the molecules involved in the anticancer activity.


Assuntos
Apoptose/efeitos dos fármacos , Inula , Extratos Vegetais/farmacologia , Encurtamento do Telômero/efeitos dos fármacos , Anexina A5/análise , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Humanos , Telomerase/metabolismo
7.
Therapie ; 64(2): 121-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19664406

RESUMO

Extracts of Withania adpressa Coss. (Solanaceae), a medicinal plant endemic to Moroccan Sahara, were tested for their cytotoxicity towards a panel of cancer cell lines (Hep2, HT29, RD, Vero and MDCK), using the (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) [MTT assay, Sigma-Aldrich]. The bioassay-guided fractionation of this plant extracts results a novel withanolide 14alpha,15alpha,17beta ,20beta-tetrahydroxy-1-oxo-(22R)-witha-2,5,24-trienolide and the already identified withanolides F and J extract, semi-purified fractions and pure compounds exhibits potent cytotoxicity against human cancer cell lines tested, in dose-dependent manner. Morphological features of treated Hep2 cells with the novel withanolide and characteristic DNA fragmentation revealed that the cytotoxicity was due to induction of apoptosis. Taken together, the results suggest that withanolides from W. adpressa Coss. hold potential as antiproliferative agents.


Assuntos
Antineoplásicos Fitogênicos , Proliferação de Células/efeitos dos fármacos , Withania/química , Vitanolídeos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular , Linhagem Celular Tumoral , Corantes , Fragmentação do DNA/efeitos dos fármacos , Humanos , Extratos Vegetais/farmacologia , Folhas de Planta/química , Sais de Tetrazólio , Tiazóis
8.
Pediatr Hematol Oncol ; 26(4): 216-31, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19437324

RESUMO

CD10 and CD34 expression in 86 Moroccan children with acute lymphoblastic leukemias (ALL) and the relevance to prognosis, diagnosis, and outcome during a 5-year follow-up were examined. At diagnosis, 57% of patients had CD10(+) blasts, while 35% had CD34(+) blasts. The CD10(+) blast frequency was much higher (80%) in B-ALL than in T-ALL (20%). The frequency of CD34(+) blasts was higher in B-ALL (48%) compared to T-ALL (16%). The 5-year survival curves showed that children with CD10(+) B-ALL had a significantly longer survival rate than those with CD10(-), as observed for T-ALL. The survival rate of B-ALL expressing CD34 was higher than that of CD34(-). Thus, CD34 and CD10 expression may have prognostic value and is associated with a better clinical outcome.


Assuntos
Antígenos CD34/imunologia , Biomarcadores Tumorais/imunologia , Neprilisina/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/mortalidade , Leucemia-Linfoma Linfoblástico de Células T Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células T Precursoras/mortalidade , Adolescente , Linfócitos B/imunologia , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Estimativa de Kaplan-Meier , Masculino , Marrocos , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células T Precursoras/diagnóstico , Taxa de Sobrevida , Linfócitos T/imunologia
9.
Tuberculosis (Edinb) ; 89(3): 210-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19447677

RESUMO

In vitro diagnosis of MTB-infection uses MTB-proteins coded for by genes of the region of differentiation 1 (RD1) of the MTB genome. This study wants to test if proteins preferentially expressed during MTB-intracellular growth might provide new targets for the diagnosis of MTB-infection. To this end seventy-five multiepitopic HLA-promiscuous MTB-peptides were designed by quantitative implemented peptide-binding motif analysis from 3 MTB-protein genes expressed in activated human macrophages (MA), 4 genes expressed during growth in non-activated human macrophages (MN-A), 12 housekeeping genes (HKG) and 6 genes of the RD1 region (RD1) as control. ELISpot for IFN-was performed to measure the responses of PBMCs deriving from 45 patients affected by active tuberculosis and 34 controls. In active-TB patients, the mean response to RD1-derived peptides was higher than that to either MA (p<0.01), MN-A (p<0.008) or HKG (p<0.01) derived peptides. In TST-positive subjects all selected peptides elicited significant IFN-T-cell responses (p<0.02 compared to TST-negatives), but without differences between the subgroups. Further, T-cell responses to RD1 peptides were lower in the 23 active-TB treated patients than in the untreated ones (p<0.01). The response to MA peptides in treated active-TB was higher than when untreated (p<0.01). These results demonstrate that the use of in vitro models of MTB-intracellular infection to select MTB gene products for further in silico and in vitro assessment of their immunogenicity have the potential to identify novel antigens amenable to the design of new tools for diagnosis and monitoring of tuberculosis.


Assuntos
Antígenos de Bactérias/genética , Proteínas de Bactérias/metabolismo , Mycobacterium tuberculosis/genética , Peptídeos/metabolismo , Linfócitos T/imunologia , Tuberculose Pulmonar/diagnóstico , Adulto , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Biomarcadores/metabolismo , Feminino , Humanos , Interferon gama/metabolismo , Tuberculose Latente/diagnóstico , Tuberculose Latente/imunologia , Macrófagos/metabolismo , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/metabolismo , Peptídeos/genética , Peptídeos/imunologia , Análise de Sequência de Proteína , Linfócitos T/metabolismo , Tuberculose Pulmonar/imunologia
10.
J Pediatr Hematol Oncol ; 29(8): 574-80, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17762501

RESUMO

Immunophenotyping in leukemia offers a precise delineation of the hematopoietic lineage and differentiation stage of the malignant cell. In this study, we used flow cytometry to determine the frequency of the immunologic types of acute lymphoblastic leukemia (ALL) in Moroccan children. We analyzed 100 samples from ALL patients within an age ranging from 6 months to 16 years presented over a 4-year period (1996 to 2000). Immunophenotyping allowed classification into 2 major categories: T-ALL (37%) and B-ALL (63%), with a higher percentage of males (69%). Comparison of the clinical characteristics showed that the frequency of splenomegaly was similar in B-ALL and T-ALL patients (53% and 47%, respectively). Hepatomegaly and mediastinal masses were more often associated with T-ALL (62% and 71%, respectively). Splenomegaly, hepatomegaly, and mediastinal masses were more frequent in immature than mature B-ALL, whereas the reverse was observed for T-ALL. Complete remission was obtained in 88% and 84% of B-ALL and T-ALL, respectively and relapse after 1 year occurred in 30% and 37% of cases, respectively. CD10 expressing B-ALL showed a slightly higher complete remission rate, whereas the reverse was observed for CD10 expressing T-ALL. The overall 5-year survival rate of ALL was 38%, whereas patients with B-ALL showed better survival than children with T-ALL.


Assuntos
Imunofenotipagem , Leucemia-Linfoma Linfoblástico de Células Precursoras/imunologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidade , Adolescente , Criança , Pré-Escolar , Humanos , Lactente , Masculino , Marrocos/epidemiologia , Neprilisina/análise , Leucemia-Linfoma Linfoblástico de Células Precursoras/classificação
11.
J Immunol Methods ; 266(1-2): 53-65, 2002 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12133622

RESUMO

Development of specifically labeled chemokines that retain their biological properties should be useful for analyzing their mechanisms of action both under physiological and pathological conditions. Here, we report the chemical synthesis and characterization of RANTES (regulated upon activation normal T cell expressed and secreted) derivatives that were biotinylated at residues 1, 25, 33, 45, or 67. Gel filtration and ultracentrifugation experiments showed that biotinylation at position 45 or 67 decreased the aggregation tendency of the chemokine to a dimeric state. Competition experiments, using a stably transfected CHO-K1 cell line overexpressing human CCR5, a RANTES receptor, indicated that derivatives biotinylated at positions 1, 25, and 67 bound to CCR5 with the same affinity as native RANTES. Flow cytometry analysis showed that RANTES biotinylated at residue 67 (B67-RANTES) bound more efficiently to primary macrophages than the other derivatives. Such binding was dependent on cell surface glycosaminoglycans (GAGs) since it was reduced when macrophages or HeLa cells expressing or not CCR5 were first treated with GAG-specific enzymes. In addition, B67-RANTES modulated CCR5 expression on lymphocytes and elicited chemotaxis of monocytes in the same manner as unmodified RANTES. Thus, B67-RANTES acts as a CCR5 agonist and may be useful to study the role of RANTES in pathologies such as, for example, human immunodeficiency virus (HIV) infection and inflammatory disorders.


Assuntos
Quimiocina CCL5/análogos & derivados , Quimiocina CCL5/farmacologia , Animais , Ligação Competitiva , Biotinilação , Células CHO , Células Cultivadas , Quimiocina CCL5/química , Quimiocina CCL5/fisiologia , Quimiotaxia , Cricetinae , Glicosaminoglicanos/metabolismo , Células HeLa , Humanos , Macrófagos/metabolismo , Monócitos/fisiologia , Receptores CCR5/metabolismo , Linfócitos T/metabolismo
12.
AIDS Res Hum Retroviruses ; 18(2): 103-13, 2002 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-11839143

RESUMO

Activating cells of the immune system may stimulate human immunodeficiency virus type 1 (HIV-1) replication and contribute to select pathogenic variants in vivo. Here, we examined the possible effect of a major pathway of immune activation, CD40 interaction with its ligand (CD40L), on the susceptibility of monocyte-derived macrophages (MDMs) to various HIV-1 strains. Stimulation of MDMs with CD40L led to reduced replication of R5 HIV-1(Ba-L), whereas this strongly enhanced the replication of X4 HIV-1(Lai) as well as of X4 primary isolates, and this was associated with strong cytopathic effects. The replication of X4 strains was inhibited by stromal cell-derived factor 1, an indication of the restricted usage of CXCR4 as virus coreceptor in this case. CD40L induced the activation of mitogen-activated protein kinases ERK1/ERK2 and stimulated MDMs to secrete RANTES (regulated on activation, normal T cell expressed and secreted), macrophage inflammatory protein 1alpha (MIP-1alpha), MIP-1beta, interleukin 6 (IL-6), IL-1beta, and tumor necrosis factor alpha. From this data, it may be hypothesized that activated macrophages represent a favorable environment for the replication of classically T lymphocyte-tropic X4 variants and, thus, may contribute significantly to the selection of such variants at late stages of clinical HIV-1 infection.


Assuntos
Antígenos CD40/imunologia , HIV-1/imunologia , Ativação de Macrófagos/imunologia , Macrófagos/imunologia , Ligante de CD40/farmacologia , Células Cultivadas , Citocinas/biossíntese , Ativação Enzimática , HIV-1/efeitos dos fármacos , HIV-1/isolamento & purificação , HIV-1/fisiologia , Humanos , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/virologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fenótipo , Replicação Viral
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