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INTRODUCTION: The role of IMP3, CDK4, MDM2 and ß-catenin proteins in Enchondroma and Central Chondrosarcoma is not totally understood. The aim of this study is to evaluate the immunoexpression of these proteins, associating histological grade, clinical data and prognosis to these tumors. METHODS: This is a retrospective-analytical study of 32 Enchondroma and 70 Central Chondrosarcoma. RESULTS: IMP3, CDK4, MDM2 and ß-catenin expression was observed in 22.82 %, 13.82 %, 17.17 % and in 8.8 % of cases, respectively. All Enchondromas positive for these immunomarkers were located in short tubular bones. The positivity for these antibodies is directly proportional to Chondrosarcoma's histological grade increase. No difference was found between Enchondroma and Chondrosarcoma, Grade 1 for IMP3, CDK4 and ß-catenin positivity. Significant metastasis outcome was observed for IMP3, CDK4, MDM2 and death for MDM2 expression. CONCLUSION: IMP3, CDK4, MDM2 and ß-catenin expression in Enchondromas of short bones phenotypically characterizes these tumors. Their expression has not proven to be useful either as diagnostic markers of these neoplasms or in distinguishing between Enchondroma and Chondrosarcoma, Grade 1. The significant immunoexpression of IMP3, CDK4 and MDM2 in metastatic Chondrosarcoma and the lower survival in those with positivity for MDM2 suggest a possible association of these proteins with tumor aggressiveness.
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Biomarcadores Tumorais , Neoplasias Ósseas , Condroma , Condrossarcoma , Quinase 4 Dependente de Ciclina , Imuno-Histoquímica , Proteínas Proto-Oncogênicas c-mdm2 , beta Catenina , Humanos , Condrossarcoma/patologia , Condrossarcoma/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/análise , Masculino , Feminino , Neoplasias Ósseas/patologia , Neoplasias Ósseas/metabolismo , Pessoa de Meia-Idade , beta Catenina/análise , beta Catenina/metabolismo , Adulto , Estudos Retrospectivos , Biomarcadores Tumorais/análise , Prognóstico , Condroma/patologia , Quinase 4 Dependente de Ciclina/metabolismo , Quinase 4 Dependente de Ciclina/análise , Idoso , Adulto Jovem , Adolescente , Gradação de Tumores , Criança , Proteínas de Ligação a RNARESUMO
TP53 gene disruption, including 17p13 deletion [del(17p)] and/or TP53 mutations, is a negative prognostic biomarker in chronic lymphocytic leukemia (CLL) associated with disease progression, treatment failure and shorter survival. Germline variants in p53 signaling pathway genes could also lead to p53 dysfunction, but their involvement in CLL has not been thoroughly evaluated. The aim of this study was to determine the association of TP53, MDM2 and NQO1 gene variability with clinical and genetic data of CLL patients. Individual genotype and haplotype data of CLL patients were compared with clinical prognostic factors, cytogenetic and molecular cytogenetic findings as well as IGHV and TP53 mutational status. The study included 116 CLL patients and 161 healthy blood donors. TP53 (rs1042522, rs59758982, rs1625895), NQO1 (rs1800566) and MDM2 (rs2279744, rs150550023) variants were genotyped using different PCR approaches. Analysis of genotype frequencies revealed no association with the risk of CLL. TP53 rs1042522, rs1625895 and MDM2 rs2279744 variants were significantly associated with abnormal karyotype and the presence of del(17p). Similarly, these two TP53 variants were associated with TP53 disruption. Moreover, TP53 C-A-nondel and G-A-del haplotypes (rs1042522-rs1625895-rs59758982) were associated with an increased likelihood of carrying del(17p) and TP53 disruptions. MDM2 T-nondel haplotype (rs2279744-rs150550023) was found to be a low risk factor for del(17p) (OR = 0.32; CI: 0.12-0.82; p = 0.02) and TP53 disruptions (OR = 0.41; CI: 0.18-0.95; p = 0.04). Our findings suggest that TP53 and MDM2 variants may modulate the risk to have chromosome alterations and TP53 disruptions, particularly del(17p). To our knowledge this is the first study of several germline variants in p53 pathway genes in Argentine patients with CLL.
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Primary hepatic liposarcoma is an extremely rare malignant tumour derived from adipocytes and is part of the group of mesenchymal tumours. We present the case of a 43-year-old Hispanic male patient with a pleomorphic hepatic liposarcoma and absence of MDM2 gene amplification. Two years and six months after surgery, the patient is asymptomatic. The present case is the first report of this entity with positive immunohistochemical testing for p16, p53, S100, vimentin and absence of MDM2 gene amplification.
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Lipossarcoma , Proteínas Proto-Oncogênicas c-mdm2 , Humanos , Masculino , Adulto , Proteínas Proto-Oncogênicas c-mdm2/genética , Lipossarcoma/patologia , Adipócitos/patologiaRESUMO
Oral squamous cell carcinoma (OSCC) represents ~90% of all oral cancers, being the eighth most common cancer in men. The overall 5-year survival rate is only 39% for metastatic cancers, and currently used chemotherapeutics can cause important side effects. Thus, there is an urgency in developing new and effective anti-cancer agents. As both chalcones and 1,2,3-triazoles are valuable pharmacophores/privileged structures in the search for anticancer compounds, in this work, new 1,2,3-triazole-chalcone hybrids were synthesized and evaluated against oral squamous cell carcinoma. By using different in silico, in vitro, and in vivo approaches, we demonstrated that compound 1f has great cytotoxicity and selectivity against OSCC (higher than carboplatin and doxorubicin) and other cancer cells in addition to showing minimal toxicity in mice. Furthermore, we demonstrate that induced cell death occurs by apoptosis and cell cycle arrest at the G2/M phase. Moreover, we found that 1f has a potential affinity for MDM2 protein, similar to the known ligand nutlin-3, and presents a better selectivity, pharmacological profile, and potential to be orally absorbed and is not a substrate of Pg-P when compared to nutlin-3. Therefore, we conclude that 1f is a good lead for a new chemotherapeutic drug against OSCC and possibly other types of cancers.
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OBJECTIVE: The embryo implantation includes a complex sequence of signaling events, comprising numerous molecular mediators, such as ovarian hormones, cytokines, adhesion molecules and, growth factors. One of the critical factors in angiogenesis is the vascular endothelial growth factor (VEGF). The VEGF plays a pivotal role in embryonic development, decidua vascularization and placental angiogenesis. Furthermore, the P53 gene and its negative regulator, murine double minute 2 (MDM2), are major players in reproductive processes. This study aimed to assess the association of polymorphisms of the VEGF and the MDM2 genes with idiopathic recurrent implantation failure. METHODS: We genotyped 60 women with previous idiopathic recurrent implantation failures and 60 fertile women as controls. Restriction Fragment Length Polymorphism (RFLP) and Sanger sequencing were used for genotyping the rs2010963 and the rs1570360 polymorphisms in VEGF; and the rs2279744 in MDM2 genes. RESULTS: Results indicated a higher frequency of the VEGF rs1570360 AA genotype and A allele in patients with a history of idiopathic implantation failure [OR=6.4 (1.22 - 33.64), p-value=0.02)]. However, the frequency of VEGF +405 G/C and MDM2 SNP309 T/G [(OR=3 (0.5 - 16) p-value=0.2, OR=1.18 (0.3 - 3.7) p-value=0.7, respectively)] genotypes were not significantly different between cases and controls. CONCLUSIONS: The VEGF polymorphism may influence embryo implantation and the VEGF rs1570360 AA genotype may predispose to the risk of recurrent implantation failure after IVF.
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Placenta , Fator A de Crescimento do Endotélio Vascular , Animais , Feminino , Humanos , Camundongos , Gravidez , Estudos de Casos e Controles , Irã (Geográfico) , Polimorfismo Genético , Proteínas Proto-Oncogênicas c-mdm2/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fatores de Crescimento do Endotélio Vascular/genéticaRESUMO
Cancer is one of the leading causes of mortality in the world. Despite the existence of diverse antineoplastic treatments, these do not possess the expected efficacy in many cases. Knowledge of the molecular mechanisms involved in tumor processes allows the identification of a greater number of therapeutic targets employed in the study of new anticancer drugs. In the last decades, peptide-based therapy design using computational chemistry has gained importance in the field of oncology therapeutics. This work aims to evaluate the electronic structure, physicochemical properties, stability, and inhibition of ETFS amino acids and peptides derived from the p53-MDM2 binding domain with action in cancer cells; by means of chemical descriptors at the DFT-BHandHLYP level in an aqueous solution, and its intermolecular interactions through molecular docking studies. The results show that The ETFS fragment plays a critical role in the intermolecular interactions. Thus, the amino acids E17, T18 and S20 increase intermolecular interactions through hydrogen bonds and enhance structural stability. F19, W23 and V25 enhance the formation of the alpha-helix. The hydrogen bonds formed by the backbone atoms for PNC-27, PNC-27-B and PNC-28 stabilize the α-helices more than hydrogen bonds formed by the side chains atoms. Also, molecular docking indicated that the PNC27B-MDM2, PNC28B-MDM2, PNC27-MDM2 and PNC28A-MDM2 complexes show the best binding energy. Therefore, DFT and molecular docking studies showed that the proposed peptides: PNC-28B, PNC-27B and PNC-28A could inhibit the binding of MDM2 to the p53 protein, decreasing the translocation and degradation of p53 native protein.
Assuntos
Aminoácidos , Proteína Supressora de Tumor p53 , Proteína Supressora de Tumor p53/química , Simulação de Acoplamento Molecular , Aminoácidos/farmacologia , Aminoácidos/metabolismo , Teoria da Densidade Funcional , Proteínas Proto-Oncogênicas c-mdm2/química , Peptídeos/química , Ligação ProteicaRESUMO
Central nervous system tumors, especially astrocytomas, are the solid neoplasms with the highest incidence and mortality rates in childhood. The diagnosis is based on histopathological characteristics, but molecular methods have been increasingly used. Translationally controlled tumor protein (TCTP) protein, encoded by the tumor protein, translationally controlled 1 (TPT1) gene, is a multifunctional protein with an important physiological role in the cell cycle. Expression of this protein has been associated with several neoplasms, including astrocytomas in adults. However, the role of this protein in pediatric astrocytomas is largely unknown. We aim to evaluate in cases of pediatric astrocytomas, the frequency of polymorphisms in the TPT1 gene and other genes associated with its molecular pathways, such as MTOR, MDM2, TP53, and CDKN1A, correlating it with protein expression and clinical variables, in formalin-fixed, paraffin-embedded (FFPE) samples. These samples were submitted to genotyping and immunohistochemistry analyses. The most revealing results refer to the MDM2 gene, rs117039649 [G/C], in which C polymorphic allele was observed only in the glioblastomas (p = .028). The CDKN1A gene, rs3176334 [T/C] presented a homozygous polymorphic genotype only in high-grade astrocytomas, when infiltrating tumors were compared (p = .039). The immunohistochemical expression of cytoplasmic MDM2 correlated with better survival rates in patients with glioblastoma (p = .018). The presence of polymorphisms in the MDM2 and CDKN1A genes, as well as a specific correlation between MDM2 expression, suggests a likely association with risk in pediatric astrocytomas. This study sought the probable role involved in the TCTP pathway, and associated proteins, in the tumorigenesis of pediatric astrocytomas, and some could have potential impact as prognostic markers in these patients.
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Astrocitoma , Neoplasias Encefálicas , Glioblastoma , Proteína Tumoral 1 Controlada por Tradução , Criança , Humanos , Astrocitoma/genética , Astrocitoma/metabolismo , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Genótipo , Polimorfismo Genético , Proteína Tumoral 1 Controlada por Tradução/genéticaRESUMO
In order to investigate the possible correlation between p53 and MDM2 co-expression with clinicopathological features of differentiated thyroid cancer (DTC) and its use as diagnostic and/or prognostic markers, we used immunohistochemistry to evaluate 317 thyroid samples including 208 DTC and 94 benign nodules, in addition to 15 normal tissues. MDM2 and p53 expression were highly associated (r = 0.7161; p < 0.0001). The co-expression of p53-MDM2 was observed more frequently in malignant lesions (p < 0.0001) and helped characterize follicular patterned lesions distinguishing FVPTC from FA (p < 0.0001) and FVPTC from FTC (p < 0.0001). In addition, p53-MDM2 co-expression was associated with characteristics of less aggressiveness. It was more frequent in patients ≤45 years old (p = 0.0035), with unique tumors (p = 0.0095), tumors <2 cm (p < 0.0001), tumors without extrathyroid invasion (p = 0.0425), without metastasis at evolution (p = 0.0179), and in patients evolving free of disease after treatment (p = 0.0485). We suggest that p53-MDM2 co-expression profile analysis might help establishing diagnostic and determining prognostic of DTC patients.
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Carcinoma Papilar/metabolismo , Imuno-Histoquímica/métodos , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Nódulo da Glândula Tireoide/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Adulto , Carcinoma Papilar/diagnóstico , Carcinoma Papilar/cirurgia , Carcinoma Papilar/ultraestrutura , Diferenciação Celular , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Recidiva , Estudos Retrospectivos , Sensibilidade e Especificidade , Glândula Tireoide/metabolismo , Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/metabolismo , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/diagnóstico , Nódulo da Glândula Tireoide/cirurgia , Nódulo da Glândula Tireoide/ultraestruturaRESUMO
p53 regulates the cellular response to genotoxic damage and prevents carcinogenic events. Theoretical and experimental studies state that the p53-Mdm2 network constitutes the core module of regulatory interactions activated by cellular stress induced by a variety of signaling pathways. In this paper, a strategy to control the p53-Mdm2 network regulated by p14ARF is developed, based on the pinning control technique, which consists into applying local feedback controllers to a small number of nodes (pinned ones) in the network. Pinned nodes are selected on the basis of their importance level in a topological hierarchy, their degree of connectivity within the network, and the biological role they perform. In this paper, two cases are considered. For the first case, the oscillatory pattern under gamma-radiation is recovered; afterward, as the second case, increased expression of p53 level is taken into account. For both cases, the control law is applied to p14ARF (pinned node based on a virtual leader methodology), and overexpressed Mdm2-mediated p53 degradation condition is considered as carcinogenic initial behavior. The approach in this paper uses a computational algorithm, which opens an alternative path to understand the cellular responses to stress, doing it possible to model and control the gene regulatory network dynamics in two different biological contexts. As the main result of the proposed control technique, the two mentioned desired behaviors are obtained.
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The tumor suppressor protein p53 is often called "the genome guardian" and controls the cell cycle and the integrity of DNA, as well as other important cellular functions. Its main function is to trigger the process of apoptosis in tumor cells, and approximately 50% of all cancers are related to the inactivation of the p53 protein through mutations in the TP53 gene. Due to the association of mutant p53 with cancer therapy resistance, different forms of restoration of p53 have been subject of intense research in recent years. In this sense, this review focus on the main currently adopted approaches for activation and reactivation of p53 tumor suppressor function, focusing on the synthetic approaches that are involved in the development and preparation of such small molecules.
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Bibliotecas de Moléculas Pequenas/farmacologia , Biologia Sintética/métodos , Proteína Supressora de Tumor p53/metabolismo , Animais , Humanos , Mutação/genética , Oncogenes , Transdução de Sinais/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Proteína Supressora de Tumor p53/genéticaRESUMO
Our group designed and synthesized the N-phenyl-piperazine LQFM030 [1-(4-((1-(4-chlorophenyl)-1H-pyrazol-4-yl)methyl) piperazin-1-yl) ethanone], a small molecule derived from molecular simplification of the Nutlin-1, an inhibitor of the human homologue of murine double minute 2 (MDM2) protein that is expressed in several types of cancer. To better investigate the effects of LQFM030 regarding the p53 mutation status, this study investigated the antiproliferative activity of LQFM030 against the p53-null K562 leukemia cells as well as the cell death pathways involved. In addition, the effects of LQFM030 on the levels of the p53/MDM2 complex were also carried out using 3T3 cells as a p53 wild-type model. Our data suggest that LQFM030 triggered apoptosis in K562 cells via different mechanisms including cell cycle arrest, caspase activation, reduction of mitochondrial activity, decrease in MDM2 expression, and transcriptional modulation of MDMX, p73, MYC, and NF-ĸB. Additionally, it promoted effects in p53/MDM2 binding in p53 wild-type 3T3 cells. Therefore, LQFM030 has antiproliferative effects in cancer cells by a p53 mutation status-independent manner with different signaling pathways. These findings open new perspectives to the treatment of leukemic cells considering the resistance development associated with cancer treatment with conventional cytotoxic drugs.
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Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Piperidinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Pirazóis/farmacologia , Proteína Supressora de Tumor p53/deficiência , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Células 3T3 BALB , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/enzimologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Camundongos , Mutação , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Transdução de Sinais , Proteína Supressora de Tumor p53/genéticaRESUMO
Stapled peptides are chemical entities in-between biologics and small molecules, which have proven to be the solution to high affinity protein-protein interaction antagonism, while keeping control over pharmacological performance such as stability and membrane penetration. We demonstrate that the multicomponent reaction-based stapling is an effective strategy for the development of α-helical peptides with highly potent dual antagonistic action of MDM2 and MDMX binding p53. Such a potent inhibitory activity of p53-MDM2/X interactions was assessed by fluorescence polarization, microscale thermophoresis, and 2D NMR, while several cocrystal structures with MDM2 were obtained. This MCR stapling protocol proved efficient and versatile in terms of diversity generation at the staple, as evidenced by the incorporation of both exo- and endo-cyclic hydrophobic moieties at the side chain cross-linkers. The interaction of the Ugi-staple fragments with the target protein was demonstrated by crystallography.
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Peptídeos/química , Peptídeos/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/química , Proteína Supressora de Tumor p53/química , Aldeídos/química , Aminas/química , Sequência de Aminoácidos , Domínio Catalítico , Cristalografia por Raios X , Cianetos/química , Polarização de Fluorescência , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Ligação Proteica , Conformação ProteicaRESUMO
PURPOSE: Dedifferentiated liposarcoma (DDLPS) is a soft tissue malignancy characterized by amplification of the mouse double minute 2 homolog (MDM2) gene. MDM2 is a negative regulator of tumor protein 53 (TP53). We tested the in vivo efficacy of BI-907828, a small molecule inhibitor of the MDM2-TP53 interaction, in two DDLPS patient-derived xenografts (PDX). METHODS: Partially immunodeficient mice were bilaterally engrafted with UZLX-STS3 (n = 24) and UZLX-STS5 (n = 24) human DDLPS tissue harboring MDM2 amplifications. Mice were grouped as follows: (a) vehicle (0.5% hydroxyethylcellullose) 10 ml/kg daily per os (p.o.); (b) doxorubicin 5 mg/kg weekly intraperitoneally (i.p.); (c) BI-907828 2.5 mg/kg daily p.o. and (d) BI-907828 10 mg/kg daily p.o. The treatment lasted for 15 days, all mice treated with BI-907828 were followed for 37 days post-treatment. Efficacy was assessed by tumor volume and histopathological evaluation. RESULTS: The 15-day treatment with 2.5 mg/kg and 10 mg/kg BI-907828 significantly inhibited tumor growth in UZLX-STS5 and -STS3 (p < 0.0001 compared to control for both models). All UZLX-STS5 and -STS3 tumors treated with BI-907828 decreased in size during treatment, and BI-907828-treated UZLX-STS5 tumors even disappeared completely. During the follow-up period, no tumor regrowth was observed in the UZLX-STS5 model and both doses of BI-907828 led to a pathological complete response, whereas a dose-dependent regrowth was seen in the UZLX-STS3 model. CONCLUSION: BI-907828 showed significant anti-tumor activity in DDLPS PDX harboring MDM2 amplifications, providing a strong rationale for early clinical testing of BI-907828 in a DDLPS patient population.
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Antineoplásicos/uso terapêutico , Amplificação de Genes , Lipossarcoma/tratamento farmacológico , Compostos Orgânicos/uso terapêutico , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-mdm2/genética , Proteína Supressora de Tumor p53/antagonistas & inibidores , Animais , Antineoplásicos/farmacologia , Doxorrubicina/efeitos adversos , Doxorrubicina/uso terapêutico , Dosagem de Genes , Humanos , Lipossarcoma/genética , Lipossarcoma/patologia , Camundongos , Compostos Orgânicos/farmacologia , Proteína Supressora de Tumor p53/genética , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
The colon is a rare site of occurrence of liposarcoma, as either the primary site or by secondary involvement from a retroperitoneal liposarcoma. Liposarcomatosis denotes simultaneous occurrence of multiple liposarcomas. There are only 17 cases of primary colonic liposarcoma reported in the English literature-one of which was primary colonic liposarcomatosis. We depict the second case of primary colonic liposarcomatosis in a 57-year-old female who presented with abdominal swelling and pain. On exploratory laparotomy, two large masses were seen arising from the wall of the right colon along with multiple smaller masses attached to the colon. Right hemicolectomy with en bloc excision of the masses was performed along with hysterectomy and pelvic floor repair. Macroscopically, multiple exophytic masses and one endophytic mass were identified. The exophytic masses were of variable size and were found to hang from the colon by a thin pedicle simulating variable-sized appendices epiploicae. Histopathologically, the lesions showed the morphology of well-differentiated liposarcoma. This appears to be a case of primary colonic liposarcomatosis. There is only one other similar case reported in the English literature, to the best of our knowledge.
RESUMO
The colon is a rare site of occurrence of liposarcoma, as either the primary site or by secondary involvement from a retroperitoneal liposarcoma. Liposarcomatosis denotes simultaneous occurrence of multiple liposarcomas. There are only 17 cases of primary colonic liposarcoma reported in the English literatureone of which was primary colonic liposarcomatosis. We depict the second case of primary colonic liposarcomatosis in a 57-year-old female who presented with abdominal swelling and pain. On exploratory laparotomy, two large masses were seen arising from the wall of the right colon along with multiple smaller masses attached to the colon. Right hemicolectomy with en bloc excision of the masses was performed along with hysterectomy and pelvic floor repair. Macroscopically, multiple exophytic masses and one endophytic mass were identified. The exophytic masses were of variable size and were found to hang from the colon by a thin pedicle simulating variable-sized appendices epiploicae. Histopathologically, the lesions showed the morphology of well-differentiated liposarcoma. This appears to be a case of primary colonic liposarcomatosis. There is only one other similar case reported in the English literature, to the best of our knowledge.
Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias do Colo/patologia , Lipossarcoma/patologia , Proteínas Proto-Oncogênicas c-mdm2/uso terapêuticoRESUMO
Inhibition of p53-MDM2 complex has been emerging as a strategy for antitumoral drug development considering the pro-apoptotic role of functional p53 in tumor cells. In our study, the prototype LQFM166 (2), designed through molecular simplification strategy inspired in the Nutlins compounds, was synthetized, characterized and the mechanisms of cell death were investigated. In addition, we estimated the starting doses for acute oral systemic toxicity tests according to the OECD Guidance Document No.129 - 3T3 NRU. The cytotoxic profile of LQFM166 (2) was determined in K-562â¯cells, a p53-null cell line, since previous studies also showed activity of LQFM166 (2) on this cells. After 24, 48 or 72â¯h of compound treatment, using MTT reduction assay, the IC50 values found were 100.1⯵M, 56.76⯵M and 45.11⯵M, respectively. LQFM166 (2) was cytotoxic for leukemia cells in a concentration-time-dependent manner. Cell death mechanisms studies of LQFM166 on K-562â¯cells, revealed that the compound induced cell cycle arrest, increased the expression of caspase 3/7, 8 and 9, cytochrome c, Bax, p21 and p27. Additionally, a decrease in the expression of the Bcl-2 and cyclin-B1 was observed. The apoptotic inducer profile of the compound was confirmed by phosphatidylserine externalization. Investigation of complexation of p53/MDM2 was carried out by ELISA assay using 3T3 cell, showing a decrease in the p53-MDM2 complex induced by the compound. Furthermore, the cytotoxicity in basal fibroblasts 3T3 was determined to estimate LD50. LQFM166 (2) reduced 3T3 cells viability with the IC50 of 185.3⯵M and estimated LD50 of 706.7â¯mg/kg (category 4 of GHS). The rationally designed of the prototype LQFM166 (2) induced cell death by apoptotic mechanisms in leukemic cells and showed MDM2 complexation antagonism in 3T3 cells.
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Apoptose/efeitos dos fármacos , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-mdm2/antagonistas & inibidores , Pirazóis/farmacologia , Células 3T3 , Animais , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ciclina B1/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Citocromos c/metabolismo , Humanos , Camundongos , Piperazinas/síntese química , Piperazinas/química , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Pirazóis/síntese química , Pirazóis/química , Proteína Supressora de Tumor p53/metabolismoRESUMO
AIM: Based upon a microarray assay, we have identified that triiodothyronine (T3) upregulates MDM2 gene expression in the rat skeletal muscle. As MDM2 protein is an E3 ligase, we hypothesized that this enzyme could play a role in T3 effects on skeletal muscle mass control. METHODS: To test our hypothesis, male rats (2 months old) were randomly assigned into the following groups: intact controls, treated with 20 physiological doses of T3 for 0.5, 1 and 7 days, or with 5, 20 and 50 physiological doses of T3 for 7 days. For in vitro experiments, myotubes and C2C12 cells were treated with T3 for 3 days. RESULTS: After validation of the microarray finding throughout RT-PCR and confirmation that T3 induces increases in MDM2 protein expression in a dose-dependent manner, we observed that MDM2 was upregulated by T3 exclusively in fibre type I. Moreover, detailed histological evaluation showed that MDM2 overexpression distributes punctiformily along the cross section of the fibre and also inside nuclei. MDM2 colocalizes with PAX7 in control muscle and T3 downregulates this myogenic factor. Pharmacological inhibition of MDM2 in cultured myotubes caused a severe decrease in their diameter (~35%, P < .001 vs Control), enhancing the effect of T3 (from ~12% to ~35%, P < .001) alone upon myotube diameter and mRNA levels of atrogenes. Finally, we observed that FOXO3 (MDM2 target) is kept outside the nucleus under T3 stimulation. CONCLUSION: Our results indicate that MDM2 might be involved in the pro-trophic effects of T3 in skeletal muscle.
Assuntos
Fibras Musculares de Contração Lenta/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-mdm2/biossíntese , Tri-Iodotironina/farmacologia , Animais , Masculino , Ratos , Ratos Wistar , Ativação Transcricional/efeitos dos fármacos , Regulação para CimaRESUMO
AIMS: This study reports the biological properties of LQFM030 in vivo, a molecular simplification of the compound nutlin-1. MAIN METHODS: Ehrlich ascites tumor (EAT)-bearing mice were treated intraperitoneally with LQFM030 (50, 75 or 150mg/kg) for 10days to determine changes in ascites tumor volume, body weight, cytotoxicity and angiogenesis. Moreover, flow cytometric expression of p53 and p21 proteins and caspase-3/7, -8 and -9 activation were investigated in EAT cells from mice treated. Acute oral systemic toxicity potential of LQFM030 in mice was also investigated using an alternative method. KEY FINDINGS: Treatment of EAT-bearing mice with LQFM030 resulted in a marked decline in tumor cell proliferation and the vascular endothelial growth factor (VEGF) levels along with enhanced survival of the mice. Apoptotic tumor cell death was detected through p53 and p21 modulation and increase of caspase-3/7, -8 and -9 activity. LQFM030 also showed orally well tolerated, being classified in the UN GHS category 5 (LD50>2000-5000mg/Kg). SIGNIFICANCE: LQFM030 seems to be a promising antitumor candidate for combinatory therapy with typical cytotoxic compounds, reducing the toxicity burden while allowing a superior anticancer activity. Moreover, these data also open new perspectives for LQFM030 as an antiangiogenic agent for treatment of diseases involving VEGF overexpression.
Assuntos
Inibidores da Angiogênese/farmacologia , Carcinoma de Ehrlich/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Piperidinas/farmacologia , Pirazóis/farmacologia , Fator A de Crescimento do Endotélio Vascular/biossíntese , Inibidores da Angiogênese/toxicidade , Animais , Apoptose/efeitos dos fármacos , Carcinoma de Ehrlich/patologia , Caspases/biossíntese , Feminino , Injeções Intraperitoneais , Masculino , Camundongos , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/patologia , Proteína Oncogênica p21(ras)/biossíntese , Proteína Oncogênica p21(ras)/genética , Piperidinas/toxicidade , Pirazóis/toxicidade , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genéticaRESUMO
The tumor suppressive role of oridonin, an active compound extracted from Rabdosia rubescens, has been proven in several gastric cancer (GC) cell lines. The present study aimed to evaluate the effect of oridonin on another GC cell line, SNU-216, and explore the potential mechanisms. The viable cell numbers, cell migration, survival fraction, and cell viability were, respectively, evaluated by trypan blue exclusion assay, wound healing assay, clonogenic assay, and CCK-8 assay. Cell apoptosis was determined by flow cytometry assay and western blot. The expression of p53 was inhibited by transient transfection, and the efficiency was verified by western blot. qRT-PCR was performed to measure the mRNA expression of p53. Western blot was used to evaluate the protein expression of apoptosis, DNA damage and p53 function related factors. We found that oridonin significantly inhibited cell proliferation, migration, and survivability, and enhanced cell apoptosis in SNU-216 cells. However, it had no influence on HEK293 cell viability. Oridonin also remarkably enhanced the anti-tumor effect of cisplatin on SNU-216 cells, as it significantly increased apoptotic cells and decreased cell viability. Moreover, the mRNA and protein expression of p53 was significantly up-regulated in oridonin-treated cells, while Mdm2 expression was down-regulated. Furthermore, oridonin enhanced p53 function and induced DNA damage. Knockdown of p53 or employing the caspase inhibitor, Boc-D-FMK, reversed the effect of oridonin on cell viability and apoptosis-related protein expression. The present study demonstrated that oridonin exhibited an anti-tumor effect on GC SNU-216 cells through regulating p53 expression and function.
Assuntos
Humanos , Neoplasias Gástricas/patologia , Carcinoma/patologia , Proteína Supressora de Tumor p53/análise , Diterpenos do Tipo Caurano/farmacologia , Antineoplásicos/farmacologia , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Dano ao DNA/efeitos dos fármacos , Carcinoma/metabolismo , Carcinoma/tratamento farmacológico , Sobrevivência Celular/efeitos dos fármacos , Western Blotting , Reprodutibilidade dos Testes , Apoptose/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Caspase 3/análise , Caspase 9/análise , Células HEK293 , Citometria de FluxoRESUMO
INTRODUCTION: The MDM2 gene plays an important role in tumorigenesis. The data on the Del1518 promoter polymorphism in the MDM2 gene have revealed associations with cancer. MATERIAL AND METHODS: We examined the role of the MDM2 Del1518 polymorphism through a comparison of the genotypes of 345 healthy Mexican women with those of 742 Mexican women with breast cancer (BC). RESULTS: The genotype frequencies of the MDM2 Del1518 polymorphism in controls and patients with BC were 64% and 55.5% for ins/ins, 32% and 31.5% for ins/del, and 4% and 13% for del/del, respectively. The obtained odds ratio (OR) was 3.26, with a 95% confidence interval (95% CI) of 1.86-5.72 and p=0.0001, for the del/del genotype. An association was evident when we examined the distribution of the del/del genotype in patients with elevated levels of transaminase SGPT (OR=2.268; 95% CI=1.40-3.65; p=0.0001). Additionally, we observed an association of the genotypes del/del - ins/del in menopausal patients with BC with the following characteristics: tobacco consumption (OR = 1.93, 95% CI = 1.07-3.4, p=0.025), pregnancy loss (OR=2.44, 95% CI=1.37-4.35, p=0.0024), obesity (I-IV) (OR=1.8, 95% CI=1.1-2.9, p= 0.018), and elevated serum glucose levels (OR=3.72, 95% CI=2.0-6.85, p=0.0001). CONCLUSIONS: The MDM2 Del1518 polymorphism was associated with BC susceptibility, particularly in menopausal patients with BC who reported tobacco consumption, pregnancy loss, obesity and high glucose levels in the analyzed Mexican population.