RESUMO
Global cancer burden increased to 14.1 million new cases in 2012; and breast cancer is the most common cancer in women worldwide, with nearly 1.7 million new cases diagnosed in 2012. Curcumin is the major bioactive ingredient extracted from the rhizome of the plant Curcuma longa (turmeric). Paclitaxel is a microtubule-stabilizing agent originally isolated from the bark of Taxus brevifolia. Curcumin and paclitaxel were evaluated with two human breast cancer cell lines as the luminal MCF-7 and the basal-like MDA-MB-231 that are either positive or negative for hormonal receptors estrogen receptor, progesterone receptor and HER2, respectively. Results indicated that curcumin combined with paclitaxel decreased c-Ha-Ras, Rho-A, p53 and Bcl-xL gene expression in comparison to control and substances alone in MCF-7 cell line. These two substances alone and combined decreased gene expression of Bcl-2 and NF-κB. However, CCND1 increased when both substances were combined in MCF-7 cells. Such substances decreased Bcl-2 and increased Bax protein expression. However, curcumin alone decreased IκBα and Stat-3 gene expression. Paclitaxel alone and combined increased IκBα and Stat-3. Curcumin alone and combined with paclitaxel increased p53, Bid, caspase-3, caspase-8 and Bax gene expression in MDA-MB-231, whereas Bcl-xL decreased such expression in MDA-MB-231 cells. When paclitaxel and curcumin were combined the expression of Bcl-2 protein was decreased. However, either substance alone and combined increased Bax protein expression corroborating the apoptotic effect of these substances. It can be concluded that curcumin may be of considerable value in synergistic therapy of breast cancer reducing the associated toxicity with use of drugs.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Neoplasias da Mama/patologia , Carcinogênese/efeitos dos fármacos , Curcumina/farmacologia , Paclitaxel/farmacologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Caspase 3/metabolismo , Caspase 8/metabolismo , Linhagem Celular Tumoral , Ciclina D1/metabolismo , Feminino , Humanos , Células MCF-7 , Inibidor de NF-kappaB alfa/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/genética , Fator de Transcrição STAT3/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética , Proteína bcl-X/biossíntese , Proteína bcl-X/genética , Proteína rhoA de Ligação ao GTP/biossíntese , Proteína rhoA de Ligação ao GTP/genéticaRESUMO
The aim of this study was to investigate the effects of the vascular endothelial growth factor (VEGF)/VEGF receptor (VEGFR)/K-ras signaling pathways on miRNA21 levels in hepatocellular carcinoma tissues in rats. Eighteen male Sprague-Dawley rats were randomly divided into normal control, model, and VEGF blocking agent groups (N = 6/group). The expression of VEGF mRNA, K-ras protein, and miRNA21 increased significantly (P < 0.05) in the model group compared with the normal control group, and decreased dramatically in the VEGF blocking agent group compared to the model group. The expression of VEGFR mRNA in the model group was higher than that of the control group, and the expression of VEGFR mRNA in the VEGF blocking agent group was significantly higher than that of the control group (P < 0.05). Statistically, there was no difference between the expression of VEGFR mRNA for the VEGF blocking agent group and the model group (P > 0.05). Finally, the expression of the miRNA21 gene in the VEGF blocking agent group was higher than in the control group, and there was a significant statistical difference noted; Pearson's correlation analysis demonstrated that the expression of K-ras protein was positively correlated with miRNA21 in the experimental groups (P = 0.001). The above results showed that the VEGF/VEGFR/K-ras signaling pathway might promote the occurrence and development of hepatocellular carcinoma cells through regulating expression of miRNA21, which has potential clinical value for the development of therapies against biological targets and determining prognosis for patients with hepatocellular carcinoma.
Assuntos
Carcinoma Hepatocelular/genética , Neoplasias Hepáticas/genética , MicroRNAs/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Fator A de Crescimento do Endotélio Vascular/biossíntese , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/biossíntese , Animais , Carcinoma Hepatocelular/induzido quimicamente , Carcinoma Hepatocelular/patologia , Dietilnitrosamina/toxicidade , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , MicroRNAs/genética , Neovascularização Patológica/genética , Neovascularização Patológica/patologia , Proteínas Proto-Oncogênicas p21(ras)/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Transdução de Sinais/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genéticaRESUMO
In Argentina, lymphomas account for 13.6% of all pediatric tumors and 47% of them are Hodgkin lymphoma. Previous studies of lymphoma series have reported the expression of apoptotic and cell cycle proteins. Our aim was to study these markers in our pediatric patients and correlate them with their outcome. Immunohistochemical staining with monoclonal antibodies anti-p53, bcl-2, p21, and mdm2 were performed on formalin-fixed paraffin-embedded Hodgkin lymphoma lymph node biopsies from 54 pediatric patients. The analyzed oncogenes p53, bcl-2, p21, and mdm2 exhibited 81%, 44%, 76%, and 90% positive staining, respectively. The most prevalent p53/p21 expression pattern was p53+/p21+, in 57% of cases, whereas concerning p53/mdm2 expression pattern p53+/mdm2+ was observed in 61% of cases. We failed to find any statistically significant correlation between oncogene expression and patient's survival. It seems that p53 plays an important role in lymphomagenesis in our studied population, because it is overexpressed in 81% of Hodgkin lymphoma cases and in more than 50% of cases, it might be able to activate its cellular effectors. Bcl-2 staining observed in 44% of our cases could represent a failure in bcl-2 down-regulation that leads to a rescue event in defective germinal center B-cells, that allows them to develop into Reed-Sternberg and Hodgkin cells.
Assuntos
Biomarcadores Tumorais/análise , Doença de Hodgkin/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Proteína Supressora de Tumor p53/biossíntese , Adolescente , Argentina , Criança , Pré-Escolar , Feminino , Doença de Hodgkin/mortalidade , Doença de Hodgkin/patologia , Humanos , Imuno-Histoquímica , Masculino , Prognóstico , Proteínas Proto-Oncogênicas c-mdm2/biossíntese , Estudos RetrospectivosRESUMO
The aim of this study was immunolabeling oncoproteins Ck14, p53, p21 and Bcl-2 in order to evaluate their expression in premalignant and malignant stomatological lesions in oral epithelial, and to compare this expression with exfoliative cytology alterations in the same patients. It was studied biopsies and cytologies of 13 subjects with oral lichen planus, with or without Human Papilloma Virus (HPV), leukoplakia and squamous cell carcinoma clinically diagnosed and confirmed by anatomopathological studies. The oral lichen planus lesion presented binuclei orange cells; and in leukoplakia lesions only orange stained was observed; meanwhile koilocytes, inflammatory cells, enlarge nuclear volume and pathogenic microorganisms were observed in the HPV infections and squamous cells carcinoma (SCC). The Ck14, p53, p21 and Bcl-2 proteins were found modified in the leukoplakia, oral lichen planus and cancer. Cytological alterations and positive immunolabeling or over-expression of Ck14 cytokeratine in the upper epithelial stratus should be indicator of malignant transformations as doing subsequence exams.
Assuntos
Carcinoma de Células Escamosas/química , Citodiagnóstico , Leucoplasia Oral/química , Líquen Plano Bucal/metabolismo , Mucosa Bucal/química , Neoplasias Bucais/química , Proteínas de Neoplasias/análise , Adulto , Idoso , Carcinoma de Células Escamosas/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Queratinas/análise , Queratinas/biossíntese , Leucoplasia Oral/metabolismo , Líquen Plano Bucal/patologia , Líquen Plano Bucal/virologia , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/metabolismo , Mucosa Bucal/patologia , Neoplasias Bucais/metabolismo , Proteínas de Neoplasias/biossíntese , Papillomaviridae/isolamento & purificação , Prognóstico , Proteínas Proto-Oncogênicas c-bcl-2/análise , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteínas Proto-Oncogênicas p21(ras)/análise , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Proteína Supressora de Tumor p53/análise , Proteína Supressora de Tumor p53/biossínteseRESUMO
BACKGROUND: Murine double minute 2 (mdm2) is a cellular protooncogene, which, in conditions of overexpression or amplification, is capable of inactivating the functions of p53, leading to tumorigenesis. Immunoexpression of mdm2 in salivary gland tumours was previously found; however, it was necessary to find out if mdm2 was overexpressed. The aim of this study was to analyse the mRNA expression of mdm2 in salivary gland neoplasms and to correlate it to immunoexpression of p53 and p21 proteins. METHODS: Specimens of different salivary gland neoplasms were obtained from surgical resections, and cell lineages derived from these tissues were established. RNA extraction was performed and mRNA expression was investigated using reverse transcription-polymerase chain reaction (RT-PCR). Cellular expression of p53 and p21 proteins was investigated by immunofluorescence technique. RESULTS: Increased expression of mdm2 was found in the majority of cell lines analysed. CONCLUSIONS: Comparing all results, we postulated that overexpression of mdm2 is related to the tumorigenesis and/or tumour progression of salivary gland neoplasms.
Assuntos
Proteínas Nucleares , Proteínas Proto-Oncogênicas/biossíntese , Neoplasias das Glândulas Salivares/metabolismo , Adenoma Pleomorfo/metabolismo , Carcinoma/metabolismo , Carcinoma Adenoide Cístico/metabolismo , Linhagem Celular Tumoral/metabolismo , Humanos , Mioepitelioma/metabolismo , Proteínas Proto-Oncogênicas c-mdm2 , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , RNA Mensageiro/biossíntese , Proteína Supressora de Tumor p53/biossínteseRESUMO
BACKGROUND: The invasive and metastatic potential of malignant cells results from complex interactions of numerous factors not yet fully understood. Genomic alterations such as ras overexpression and nm23-H1 inhibition have been found to be frequently associated with increased invasiveness in various cancers. On the other hand, secretion of different proteinases are necessary for malignant cells to traverse a network of matrix macromolecules, but the relationship between the genomic alterations and the proteolytic phenotype is still unclear. Our aim was to investigate whether the appearance of the proteolytic phenotype had any correlation with the expression of H-ras and nm23-H1 genes in carcinoma of the uterine cervix. METHODS: Twenty-five samples from patients with carcinoma of the uterine cervix at different clinical stages were studied. Cathepsin B1, plasminogen activator, and collagenase activity were assessed in tissue cytosols using specific synthetic oligopeptides as substrates. The expression of H-ras and nm23-H1 was investigated by means of immunohistochemistry and in situ hybridization. RESULTS: Our results showed that cathepsin B1 was the most consistently elevated proteinase, demonstrating a linear correlation with clinical staging. H-ras expression was found elevated in 40% of the cases. Nm23-H1 protein immunoreactivity was positive in 40% of the cases. No correlation was found among H-ras, cathepsin B1 activity, and survival rate. Among cases with high cysteine proteinase activity, a different clinical behavior depending on the expression of Nm23-H1 was observed. The cases with Nm23-H1 protein had a markedly better survival rate than those lacking this protein. In contrast, the absence of Nm23-H1 in association with high cathepsin B1 activity was a clear indicator of a poor prognosis. CONCLUSIONS: These findings suggest a complex interaction between the proteolytic phenotype and the expression of H-ras and nm23-H1 genes in carcinoma of the cervix that influences the clinical behavior of the tumor.
Assuntos
Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Genes ras , Proteínas Monoméricas de Ligação ao GTP/biossíntese , Proteínas de Neoplasias/biossíntese , Núcleosídeo-Difosfato Quinase , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Fatores de Transcrição/biossíntese , Neoplasias do Colo do Útero/genética , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Catepsina B/análise , Colagenases/análise , Citosol/química , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Hibridização In Situ , Proteínas Monoméricas de Ligação ao GTP/genética , Nucleosídeo NM23 Difosfato Quinases , Invasividade Neoplásica/genética , Proteínas de Neoplasias/genética , Estadiamento de Neoplasias , Inibidor 1 de Ativador de Plasminogênio/análise , Fatores de Transcrição/genética , Neoplasias do Colo do Útero/metabolismo , Neoplasias do Colo do Útero/patologiaRESUMO
When HeLa cells were selected for stable expression of a neo gene, linked either to mutated or wt c-H-ras genes, morphological examination of selected clones from several experiments revealed formation of giant multinucleated cells. These morphological alterations culminate in cell death, as a consequence of mitotic catastrophe (or mitotic death). Although clones expressing the mutated gene produced significantly larger numbers of these giant cells, those transfected with the normal allele were also found to produce significantly more giant multinucleated cells than non-transfected HeLa cells. Northern blot analysis of mRNA revealed overexpression of the normal H-ras gene in these clones. Chromatin structure analysis of these clones showed gross alterations, including the presence of micronuclei and heteroploid nuclei. Interestingly, odd numbers of nuclei were found in colonies of these giant cells. In addition, alterations in cell cycle parameters were observed, including the appearance of a subpopulation of cells with an abnormal content of DNA, probably representing dying cells. Our data support the notion that abnormal expression of H-ras contributes to mitotic catastrophe and death of a subpopulation of HeLa cells.
Assuntos
Morte Celular , Expressão Gênica , Genes ras , Mitose/genética , Proteínas Proto-Oncogênicas p21(ras)/biossíntese , Northern Blotting , Ciclo Celular/genética , Núcleo Celular/ultraestrutura , Aberrações Cromossômicas , Transtornos Cromossômicos , Células HeLa , Humanos , Canamicina Quinase , Cinética , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Proteínas Recombinantes/biossíntese , Fatores de Tempo , TransfecçãoRESUMO
The expression of c-myc and p-ras-21 oncogenes was studied using an immunohistochemical method with monoclonal antibodies in 126 samples of gallbladder carcinoma (103 primary tumors and 23 metastatic lesions). Twenty five gallbladder samples without tumor evidence were used as controls. C-myc oncoprotein was positive in one control sample and p-ras-21 oncoprotein was negative in all. Among primary carcinomas c-myc was positive in 9 (9%) and p-ras-21 in 4 (4%); among metastatic carcinomas c-myc was positive in 6 (26%, p = 0.03 vs primary carcinoma) and p-ras-21 in 11 (48%, p < 0.001 vs primary carcinoma). There was a non significant association between c-myc and p-ras-21 expression and degree of histological differentiation and level of tumoral infiltration. It is concluded that c-myc and p-ras-21 oncoprotein expression is observed in less than 10% of primary gallbladder carcinomas and that this expression is significantly higher in metastatic carcinomas. This may reflect an activation or overexpression of these oncogenes in metastatic cells.