IMMUNOEXPRESSION OF DEK AND PHOSPHO-P38 PROTEINS IN RECTAL CANCER BEFORE CHEMORADIATION THERAPY.

BACKGROUND: Colorectal cancer is the third cause of cancer worldwide and a quarter of them are in the rectum. DEK oncogene is involved in several nuclear processes and can accelerate tumorigenesis. OBJECTIVE: This study aims to evaluate the immunoexpression of DEK and Phospho-P38 proteins before neoadjuvant therapy in patients with rectum adenocarcinoma and correlate it with a clinical response and survival. METHODS: Patients with adenocarcinoma of the middle and low rectum who underwent chemotherapy and radiotherapy followed by surgical tumor resection were included. The expression and quantification were studied by immunohistochemistry in the tumor biopsy tissues using a HScore system. Score ≥4 were considered positive and those with <4 negative. RESULTS: 22 patients were included with a mean age of 63.55 years (SD: ±13.49). The clinical-stage before treatment was T3 on 72.7%, T4 on 18.2%, 31.8% were N1, 50% N0 and all M0. After chemo and radiotherapy, 54.6% were T3; 22.7% were classified as T2; 9.1% as T1, and 13.6% were T0. Among the tumors, 22.7% were positive for DEK and 63.6% positive for Phospho-P38. There was a positive correlation between DEK protein before treatment and pTNM stage (P=0.011). Phospho-P38 protein showed no correlation with these parameters. Patients with a negative HScore had a mean survival of 141.33 months (95%CI: 112.41-170.25) and those with a positive HSscore had a mean survival of 25.10 months (95%CI: 17.36-32.84; P<0.001). CONCLUSION: A higher expression of DEK was observed in advanced stages. Patients who presented DEK expression <4 had a higher survival, being a factor of worst prognosis.

Immunoexpressão das proteínas DEK e Fosfo-P38 no câncer retal antes da quimiorradioterapia / Immunoexpression of dek and phospho-p38 proteins in rectal cancer before chemoradiation therapy

ABSTRACT Background: Colorectal cancer is the third cause of cancer worldwide and a quarter of them are in the rectum. DEK oncogene is involved in several nuclear processes and can accelerate tumorigenesis. Objective: This study aims to evaluate the immunoexpression of DEK and Phospho-P38 proteins before neoadjuvant therapy in patients with rectum adenocarcinoma and correlate it with a clinical response and survival. Methods: Patients with adenocarcinoma of the middle and low rectum who underwent chemotherapy and radiotherapy followed by surgical tumor resection were included. The expression and quantification were studied by immunohistochemistry in the tumor biopsy tissues using a HScore system. Score ≥4 were considered positive and those with <4 negative. Results: 22 patients were included with a mean age of 63.55 years (SD: ±13.49). The clinical-stage before treatment was T3 on 72.7%, T4 on 18.2%, 31.8% were N1, 50% N0 and all M0. After chemo and radiotherapy, 54.6% were T3; 22.7% were classified as T2; 9.1% as T1, and 13.6% were T0. Among the tumors, 22.7% were positive for DEK and 63.6% positive for Phospho-P38. There was a positive correlation between DEK protein before treatment and pTNM stage (P=0.011). Phospho-P38 protein showed no correlation with these parameters. Patients with a negative HScore had a mean survival of 141.33 months (95%CI: 112.41-170.25) and those with a positive HSscore had a mean survival of 25.10 months (95%CI: 17.36-32.84; P<0.001). Conclusion: A higher expression of DEK was observed in advanced stages. Patients who presented DEK expression <4 had a higher survival, being a factor of worst prognosis.

RESUMO Contexto: O câncer colorretal é mundialmente, a terceira causa de câncer e um quarto destes estão localizados no reto. O oncogene DEK está envolvido em vários processos nucleares e pode acelerar a tumorigênese. Objetivo: Este estudo tem como objetivo avaliar a imunoexpressão das proteínas DEK e Fosfo-P38 antes da terapia neoadjuvante em pacientes com adenocarcinoma de reto e correlacioná-la com resposta clínica e sobrevida. Métodos: Foram incluídos pacientes com adenocarcinoma de reto médio e baixo submetidos à quimio e radioterapia seguida de ressecção cirúrgica do tumor. A expressão e quantificação foram estudadas por imuno-histoquímica nos tecidos de biópsia tumoral utilizando um sistema HScore. Escores ≥4 foram considerados positivos e aqueles com <4 negativos. Resultados: Foram incluídos 22 pacientes com média de idade de 63,55 anos (DP: ±13,49). O estágio clínico antes do tratamento era T3 em 72,7%, T4 em 18,2%, 31,8% eram N1, 50% N0 e todos M0. Após a quimio e radioterapia, 54,6% eram T3; 22,7% eram T2; 9,1% eram T1 e 13,6% T0. Entre os tumores, 22,7% foram positivos para DEK e 63,6% positivos para Phospho-P38. Houve uma correlação positiva para a imunoexpressão da proteína DEK e o estágio pTNM (P=0,011). A proteína fosfo-P38 não apresentou correlação com esses parâmetros. Pacientes com HScore negativo para DEK tiveram sobrevida média de 141,33 meses (IC95%: 112,41-170,25) e aqueles com HScore positivo tiveram sobrevida média de 25,10 meses (IC95%: 17,36-32,84) (P<0,001). Conclusão: Observou-se maior expressão de DEK em estágios avançados. Os pacientes que apresentaram expressão de DEK <4 tiveram maior sobrevida, sendo um fator de pior prognóstico.

p53, Cyclin-D1, ß-catenin, APC and c-myc in Tumor Tissue from Colorectal and Gastric Cancer Patients with Suspected Lynch Syndrome by the Bethesda Criteria.

Colorectal cancer (CRC) is one of the most frequent neoplasms worldwide, and up to 15% have a family history. Lynch syndrome (LS) is a hereditary cause of CRC and gastric (GC). Individuals with LS have mutations in mismatch genes repair. p53, cyclin D1, ß-catenin, APC and c-myc proteins are involved in the cell cycle and carcinogenesis. OBJECTIVE: To study the expression of p53, Cyclin D1, ß-catenin, APC and c-myc proteins in patients with CRC and GC with at least one of the Bethesda positive criteria. Compare the expression of these proteins with the presence or absence of expression of the DNA repair proteins. PATIENTS AND METHODS: We included 70 individuals with CRC or GC with at least one of the Bethesda positive criteria. Protein expression of MLH1, MSH2, MSH6, PMS2, p53, cyclin D1, ß-catenin, APC and c-myc were analized by immunohistochemistry tumours tissues. RESULTS: Deficient expression of MLH1, MSH2, MSH6 and PMS2 were respectively 38.7%; 17.7%; 26.22% and 48.38%. We found a negative association between deficiency of PMS2 and age, and positive association between PMS2 deficiency and APC positive. The positive imunoexpression of APC increases by 4 times the chance of having deficiency of PMS2. CONCLUSIONS: Patients with loss of expression of PMS2 had a higher risk of mutation or deletion of APC and tumours with positive immunoexpression of cyclin D1 had an increased risk of loss of expression of MSH2. These results suggest that tumours with loss of expression of DNA repair proteins had a higher loss of cell control cycle.
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The Role of Dimethoate and UV-B on Skin of Wistar Rats.

BACKGROUND/AIM: The pesticide dimethoate (O-dimethyl-S- Nmethylcarbamoylmethyl phosphorodithioate) is able to induce severe acute toxicity in living organisms. The aim of this study was to evaluate the effects of ultraviolet radiation, alone or combined with exposure to dimethoate, on the rat skin. MATERIALS AND METHODS: A total of 38 Wistar female rats (Rattus norvegicus albinus), were distributed into four groups: A (n=9) control group, B (n=10) exposed to ultraviolet-B radiation (UV-B), C (n=10) exposed to UV-B followed by application of dimethoate (UV-B+AGRO) and group D (n=9) exposed to dimethoate (AGRO). Histological examination of the tissues, as well as immunohistochemistry for cleaved caspase 3, Ki-67 and COX-2 expression were performed to all groups. RESULTS: Animals submitted to UV-B exhibited hyperkeratosis with moderate cell atypia. Regarding exposure to UV-B+AGRO, the animals presented hyperkeratosis and atrophy, whereas in animals exposed to AGRO, only atrophy was noticed. The immunohistochemical results on skin revealed that UVB, AGRO and UVB+AGRO decreased cleaved caspase 3 and Ki-67 expression when compared to the control group (p<0.05). COX-2 expression decreased to UVB or AGRO groups compared to controls (p<0.05). CONCLUSION: UV-B or AGRO exposure is able to induce histopathological changes and altered expression of cleaved caspase-3 and Ki-67 in rat skin, thus being categorized as a risk condition for skin carcinogenesis.

Association of expression of inflammatory response genes and DNA repair genes in colorectal carcinoma.

Inflammation is an important etiological factor of colorectal carcinoma and may be related to colorectal carcinoma growth and proliferation. This study aimed to verify whether the presence of chronic inflammation represented by tumor necrosis factor-α, interleukin-2, interleukin-6, and interleukin-10 gene expression is related to hMLH1, hMSH2, hMSH6, and PMS2 gene expression and the corresponding protein levels of these genes from the DNA repair system. A total of 83 patients were operated on for curative or palliative colorectal carcinoma. Expression of the inflammatory response genes tumor necrosis factor-α, interleukin-2, interleukin-6, and interleukin-10 as well as expression of the hMLH1, hMSH2, hMSH6, and PMS2 genes of the DNA repair system (mismatch repair) and the expression levels of the corresponding mismatch repair proteins were measured in neoplastic tissue by reverse transcription polymerase chain reaction and immunohistochemistry, respectively. Associations were observed between hMSH6 mRNA expression and interleukin-2 mRNA expression (p = 0.026) as well as between hMLH1 and hMSH2 gene expression and tumor necrosis factor-α gene expression (p = 0.042). Higher tissue levels of interleukin-2 and tumor necrosis factor-α gene expression were associated with lower hMSH6, hMLH1, and hMSH2 gene expression.

THE CANONICAL WNT PATHWAY IN GASTRIC CARCINOMA.

BACKGROUND: It is believed that the Wnt pathway is one of the most important signaling involved in gastric carcinogenesis. AIM: To analyze the protein expression of canonical and non-canonical Wnt pathways in gastric carcinoma. METHOD: The immunohistochemistry was performed in 72 specimens of gastric carcinomas for evaluating the expression of Wnt-5a, FZD5, GSK3ß, axin, CK1, ubiquitin, cyclin D1 and c-myc. RESULTS: There were significant differences for cytoplasm and nucleus ubiquitin for moderately and well differentiated tumors (p=0.03) and for those of the intestinal type of the Lauren classification (p=0.03). The absence of c-myc was related to Lauren's intestinal tumors (p=0.03). Expression of CK1 in the cytoplasm was related to compromised margin (p=0.03). Expression of cyclin D1 protein was more intense in male patients (p=0.03) There was no relation of the positive or negative expression of the Wnt-5a, FZD5, GSK3 and Axin with any clinicopathological variables. CONCLUSION: The canonical WNT pathway is involved in gastric carcinoma.

The canonical wnt pathway in gastric carcinoma / Via canônica do wnt no carcinoma gástrico

ABSTRACT Background : It is believed that the Wnt pathway is one of the most important signaling involved in gastric carcinogenesis. Aim : To analyze the protein expression of canonical and non-canonical Wnt pathways in gastric carcinoma. Method : The immunohistochemistry was performed in 72 specimens of gastric carcinomas for evaluating the expression of Wnt-5a, FZD5, GSK3β, axin, CK1, ubiquitin, cyclin D1 and c-myc. Results : There were significant differences for cytoplasm and nucleus ubiquitin for moderately and well differentiated tumors (p=0.03) and for those of the intestinal type of the Lauren classification (p=0.03). The absence of c-myc was related to Lauren's intestinal tumors (p=0.03). Expression of CK1 in the cytoplasm was related to compromised margin (p=0.03). Expression of cyclin D1 protein was more intense in male patients (p=0.03) There was no relation of the positive or negative expression of the Wnt-5a, FZD5, GSK3 and Axin with any clinicopathological variables. Conclusion: The canonical WNT pathway is involved in gastric carcinoma.

RESUMO Racional : Acredita-se que a via Wnt é uma das mais importantes da sinalização envolvidas na carcinogênese gástrica. Objetivos : Analisar a expressão das proteínas das vias Wnt canônicas e não-canônicas no carcinoma gástrico e relacionar sua expressão com as variáveisclinicopatológicas. Método : Foram coletadas 72 amostras de carcinoma gástrico, e áreas representativas do tumor foram selecionadas para o Tissue Microarray. Imunoistoquímica foi realizada para avaliar a expressão de Wnt-5a, FZD5, GSK3β, axina, CK1, ubiquitina, ciclina D1 e c-myc. Resultados : Houve diferenças significativas para a expressão de ubiquitina no citoplasma e núcleo para tumores moderadamente e bem diferenciados (p=0,03) e para aqueles do tipo intestinal da classificação de Lauren (p=0,03). A expressão negativa da proteína c-myc no citoplasma foi relacionada aos tumores intestinais de Lauren (p=0,028). A expressão positiva de CK1 no citoplasma das células neoplásicas foi relacionada a tumores com margens cirúrgicas livre de envolvimento neoplásico (p=0,03). A expressão positiva da proteína ciclina D1 foi maior nos tumores dos homens (p=0,03). Não houve relação da expressão positiva ou negativa das proteínas Wnt-5a e FZD5 no citoplasma ou núcleo com quaisquer variáveis clinicopatológicas. O mesmo foi observado para GSK3β e Axin. Conclusões : A relação da expressão das proteínas da via canônica com as variáveis epidemiológicas e tumorais sugere sua participação na carcinogênese gástrica. Por outro lado, a ausência da relação das expressões das proteínas da via não-canônica sugere sua não participação na carcinogênese gástrica.

The Anti-Inflammatory Potential of Mimosa caesalpiniifolia Following Experimental Colitis: Role of COX-2 and TNF-Alpha Expression.

The aim of this study was to evaluate the preventive and/or protective action of Mimosa caesalpiniifolia (M. caesalpiniifolia) following experimental colitis in rats. The rats were randomized into ten groups (n=10 per group), as follows: G1 - Sham group:; G2 - TNBS group; G3, G4 -colitis and treated with hydroalcoholic extract of M. caesalpiniifolia 250 mg/kg/day after and before/after inducing colitis, respectively; G5, G6 - colitis and treated with hydroalcoholic extract of M. caesalpiniifolia at 125 mg/kg/day after and before/after inducing colitis respectively; G7,G8 - colitis and treated with ethylacetate fraction of M. caesalpiniifolia at 50 mg/kg/day after and before/after inducing colitis, respectively; G9,G10 - colitis and treated with ethylacetate fraction of M. caesalpiniifolia at 50 mg/kg/day after and before/after inducing colitis, respectively. Rats treated with hydroalcoholic extract of M. caesalpiniifolia for both doses showed lower tissue damage in the distal colon. Ethylacetate fraction was effective at the highest dose only when administrated after inducing colitis. A downregulation of COX-2 was detected to rats suffering colitis and treated with M. caesalpiniifolia at high dose. On the other hand, TNF-alpha immunoexpression decreased in groups treated with M. caesalpiniifolia at low dose after inducing colitis. In summary, our results suggest that M. caesalpiniifolia attenuated the lesions of the colon, reduced inflammation, and modulates the expression of COX-2 and TNF-α during chronic colitis induced by TNBS when using for therapeutic purposes on a dose-dependent manner.

Do Dental X-Rays Induce Genotoxicity and Cytotoxicity in Oral Mucosa Cells? A Critical Review.

Dental X-rays are widely used in clinical practice, since the technique is an important approach for diagnosing diseases in dental and periodontal tissues. However, it is widely known that radiation is capable of causing damage to cellular systems, such as genotoxicity or cytotoxicity. Thus, the aim of this review was to present a critical analysis regarding the studies published on genotoxicity and cytotoxicity induced by dental X-rays in oral mucosa cells. Such studies have revealed that some oral cell types are more sensitive than others following exposure to dental X-rays. Certainly, this review will contribute to a better understanding of this matter as well as to highlighting perspectives for further studies. Ultimately, such data will promote better safety for both patients and dental professionals.

Fluoride Induces Apoptosis in Mammalian Cells: In Vitro and In Vivo Studies.

Apoptosis is genetically programmed cell death, an irreversible process of cell senescence with characteristic features different from other cellular mechanisms of death such as necrosis. In the last years, apoptosis has been extensively studied in the scientific literature, because it has been established that apoptosis plays a crucial role following the time course of chronic degenerative diseases, such as cancer. Thus, several researchers have strugged to detect what chemical agents are able to inter fere with the apoptotic process. Thus, the purpose of this literature review is to assess if fluoride induces apoptosis in mammalian cells using in vivo and in vitro test systems. Certain mammalian cell types such as oral cells, blood and brain were exetensively investigated; the results showed that fluoride is able to induce apoptosis in both intrinsinc and extrinsic pathways. Moreover, other cells types have been poorly investigated such as bone, kidney and reproductive cells with conflicting results so far. Therefore, this area needs further investigation for the safety of human populations exposed to fluoride in a chronic way, as for example in developing countries.

Putative mechanisms of genotoxicity induced by fluoride: a comprehensive review.

Genotoxicity is the ability of an agent to produce damage on the DNA molecule. Considering the strong evidence for a relationship between genetic damage and carcinogenesis, to elucidate the putative mechanisms of genotoxicity induced by fluoride are important to measure the degree of risk involved to human populations. The purpose of this article is to provide a comprehensive review on genotoxicity induced by fluoride on the basis of its mechanisms of action. In the last 10 years, all published data showed some evidence related to genotoxicity, which is due to mitochondrial disruption, oxidative stress, and cell cycle disturbances. However, this is an area that still requires a lot of investigation since the published data are not sufficient for clarifying the genotoxicity induced by fluoride. Certainly, the new information will be added to those already established for regulatory purposes as a safe way to promote oral healthcare and prevent oral carcinogenesis.

Cytogenetic Biomonitoring in Buccal Mucosal Cells from Municipal Solid Waste Collectors.

Waste collectors collect, transport, and process the garbage produced by people living in the city. Nowadays, this activity requires special attention due to the environmental impact of garbage and its potential consequences on human health. The aim of this study was to evaluate potential cytotoxic and mutagenic effects of garbage collection on waste collectors. For this purpose, a total of 47 male waste collectors aged from 24 to 53 years were included in the experimental group. A total of 30 men matched by age were used as the control group. Cytotoxicity and mutagenicity were analyzed by micronucleus test in buccal mucosaI cells. No statistically significant difference (p>0.05) in the frequency of micronuclei was detected in the waste collectors when compared to controls. Nevertheless, higher frequencies of karyolysis and pyknosis (p<0.05) were detected in buccal mucosaI cells from waste collectors when compared to matched controls. Taken together, our results indicate that waste collectors comprise an at-risk group as a result of increased cytotoxicity apparent from buccal mucosa cells.

Expression of e-cadherin and wnt pathway proteins betacatenin, apc, tcf-4 and survivin in gastric adenocarcinoma: clinical and pathological implication / Expressão da e-caderina e das proteínas da via de sinalização wnt betacatenina, apc, tcf-4 e survivina no adenocarcinoma gástrico: implicações clínica e patológica

ABSTRACT Background: Gastric cancer is the fifth most frequent cancer and the third most common cause of cancer-related deaths worldwide.It has been reported that Wnt/ betacatenin pathway is activated in 30-50% of these tumors. However,the deregulation of this pathway has not been fully elucidated. Aim: To determine the expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins in gastric adenocarcinoma tissues and correlate with clinical and pathological parameters. Method: Seventy-one patients with gastric adenocarcinoma undergoing gastrectomy were enrolled. The expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins was detected by immunohistochemistryand related to the clinical and pathological parameters. Results: The expression rates of E-cadherin in the membrane was 3%; betacatenin in the cytoplasm and nucleus were 23,4% and 3,1% respectively; APC in the cytoplasm was 94,6%; TCF-4 in the nucleus was 19,4%; and survivin in the nucleus 93,9%. The expression rate of E-cadherin was correlated with older patients (p=0,007), while betacatenin with tumors <5 cm (p=0,041) and APC with proximal tumors (p=0,047). Moreover, the expression of TCF-4 was significantly higher in the diffuse type (p=0,017) and T4 tumors (p=0,002). Conclusion: The Wnt/betacatenin is not involved in gastric carcinogenesis. However, the high frequency of survivin allows to suggest that other signaling pathways must be involved in the transformation of gastric tissue.

RESUMO Racional: O câncer gástrico encontra-se entre as principais neoplasias malignas do mundo sendo o quinto mais incidente e o terceiro em relação ao índice de mortalidade. Acredita-se que a via Wnt/betacatenina esteja ativada em 30-50% desses tumores, porém a desregulação dela ainda não está completamente esclarecida. Objetivo: Avaliar a imunoexpressão das proteínas E-caderina, betacatenina, APC, TCF-4 e survivina em tecidos de adenocarcinoma gástrico e correlacioná-las com as variáveis clínicas dos doentes e anatomopatológicas do tumor. Método: Foram coletados os dados clínicos e anatomopatológicos dos prontuários de 71 doentes com adenocarcinoma gástrico submetidos à gastrectomia. O material obtido na operação foi submetido à análise imunoistoquímica e a frequência da expressão de cada proteína pôde ser analisada de acordo com a sua localização na célula e relacionada com as variáveis clinicopatológicas. Resultados: A graduação percentualda expressão e da localização das proteínas foi a seguinte: E-caderina em 3% na membrana; betacatenina em 23,4% no citoplasma e 3,1% no núcleo; APC em 94,6% no citoplasma; TCF-4 em19,4% no núcleo; e survivina em 93,9% no núcleo. Houve relação entre expressão da proteína E-caderina com a idade mais avançada (p=0,007); betacatenina com tumores <5 cm de diâmetro (p=0,041);APC com tumores proximais (p=0,047); e TCF-4 com tipo difuso da classificação de Lauren (p=0,017) e com o grau de penetração tumoral (p=0,002). Conclusão: A via Wnt/betacatenina não está envolvida na carcinogênese gástrica. Porém, a frequência elevada de survivina permite sugerir que outras vias sinalizadoras devam estar envolvidas na transformação do tecido gástrico.

The destruction complex of beta-catenin in colorectal carcinoma and colonic adenoma.

OBJECTIVE: To evaluate the destruction complex of beta-catenin by the expression of the proteins beta-catetenin, adenomatous polyposis coli, GSK3ß, axin and ubiquitin in colorectal carcinoma and colonic adenoma. METHODS: Tissue samples from 64 patients with colorectal carcinoma and 53 patients with colonic adenoma were analyzed. Tissue microarray blocks and slides were prepared and subjected to immunohistochemistry with polyclonal antibodies in carcinoma, adjacent non-neoplastic mucosa, and adenoma tissues. The immunoreactivity was evaluated by the percentage of positive stained cells and by the intensity assessed through of the stained grade of proteins in the cytoplasm and nucleus of cells. In the statistical analysis, the Spearman correlation coefficient, Student's t, χ2, Mann-Whitney, and McNemar tests, and univariate logistic regression analysis were used. RESULTS: In colorectal carcinoma, the expressions of beta-catenin and adenomatous polyposis coli proteins were significantly higher than in colonic adenomas (p<0.001 and p<0.0001, respectively). The immunoreactivity of GSK3ß, axin 1 and ubiquitin proteins was significantly higher (p=0.03, p=0.039 and p=0.03, respectively) in colorectal carcinoma than in the colonic adenoma and adjacent non-neoplastic mucosa. The immunohistochemistry staining of these proteins did not show significant differences with the clinical and pathological characteristics of colorectal cancer and colonic adenoma. CONCLUSIONS: These results suggest that, in adenomas, the lower expression of the beta-catenin, axin 1 and GSK3ß proteins indicated that the destruction complex of beta-catenin was maintained, while in colorectal carcinoma, the increased expression of beta-catenin, GSK3ß, axin 1, and ubiquitin proteins indicated that the destruction complex of beta-catenin was disrupted. OBJETIVO: Avaliar o complexo de destruição da betacatenina no carcinoma colorretal e no adenoma do colo pela expressão das proteínas betacatenina, adenomatous polyposis coli, GSK3ß, axina e ubiquitina. MÉTODOS: Amostras de tecidos de 64 doentes com carcinoma colorretal e de 53 pacientes com adenoma do colo foram analisadas. Blocos de tecidos foram submetidos ao estudo imuno-histoquímico com anticorpos policlonais nos tecidos do carcinoma, mucosa não neoplásica adjacente e adenoma. A imunorreatividade foi avaliada pela porcentagem de positividade de células coradas e pela intensidade do grau de coloração das proteínas no citoplasma e no núcleo das células. Na análise estatística, foram utilizados o coeficiente de correlação de Spearman, os testes t de Student, χ2, Mann-Whitney e de McNemar, e a análise de regressão logística univariada. RESULTADOS: No carcinoma colorretal, as expressões da betacatenina e da adenomatous polyposis coli foram significativamente maiores do que em adenomas do colo (p<0,001 e p<0,0001, respectivamente). A imunorreatividade das proteínas GSK3ß, axina 1 e ubiquitina foi significativamente maior (p=0,03, p=0,039 e p=0,03, respectivamente) no carcinoma colorretal do que no adenoma e na mucosa não neoplásica adjacente. A coloração imuno-histoquímica dessas proteínas não apresentou diferenças significantes em relação às características clinicopatológicas do câncer colorretal e do adenoma. CONCLUSÕES: Em adenomas, as menores expressões de betacatenina, axina 1 e GSK3ß indicaram que o complexo de destruição da betacatenina estava conservado, enquanto que, no carcinoma colorretal, o aumento das expressões da betacatenina, GSK3ß, 1 axina, e ubiquitina indicaram que o complexo de destruição de betacatenina estava alterado.

The destruction complex of beta-catenin in colorectal carcinoma and colonic adenoma / O complexo destruidor de betacatenina no carcinoma colorretal e no adenoma cólico

ABSTRACT Objective To evaluate the destruction complex of beta-catenin by the expression of the proteins beta-catetenin, adenomatous polyposis coli, GSK3β, axin and ubiquitin in colorectal carcinoma and colonic adenoma. Methods Tissue samples from 64 patients with colorectal carcinoma and 53 patients with colonic adenoma were analyzed. Tissue microarray blocks and slides were prepared and subjected to immunohistochemistry with polyclonal antibodies in carcinoma, adjacent non-neoplastic mucosa, and adenoma tissues. The immunoreactivity was evaluated by the percentage of positive stained cells and by the intensity assessed through of the stained grade of proteins in the cytoplasm and nucleus of cells. In the statistical analysis, the Spearman correlation coefficient, Student’s t, χ2, Mann-Whitney, and McNemar tests, and univariate logistic regression analysis were used. Results In colorectal carcinoma, the expressions of beta-catenin and adenomatous polyposis coli proteins were significantly higher than in colonic adenomas (p<0.001 and p<0.0001, respectively). The immunoreactivity of GSK3β, axin 1 and ubiquitin proteins was significantly higher (p=0.03, p=0.039 and p=0.03, respectively) in colorectal carcinoma than in the colonic adenoma and adjacent non-neoplastic mucosa. The immunohistochemistry staining of these proteins did not show significant differences with the clinical and pathological characteristics of colorectal cancer and colonic adenoma. Conclusions These results suggest that, in adenomas, the lower expression of the beta-catenin, axin 1 and GSK3β proteins indicated that the destruction complex of beta-catenin was maintained, while in colorectal carcinoma, the increased expression of beta-catenin, GSK3β, axin 1, and ubiquitin proteins indicated that the destruction complex of beta-catenin was disrupted.

RESUMO Objetivo Avaliar o complexo de destruição da betacatenina no carcinoma colorretal e no adenoma do colo pela expressão das proteínas betacatenina, adenomatous polyposis coli, GSK3β, axina e ubiquitina. Métodos Amostras de tecidos de 64 doentes com carcinoma colorretal e de 53 pacientes com adenoma do colo foram analisadas. Blocos de tecidos foram submetidos ao estudo imuno-histoquímico com anticorpos policlonais nos tecidos do carcinoma, mucosa não neoplásica adjacente e adenoma. A imunorreatividade foi avaliada pela porcentagem de positividade de células coradas e pela intensidade do grau de coloração das proteínas no citoplasma e no núcleo das células. Na análise estatística, foram utilizados o coeficiente de correlação de Spearman, os testes t de Student, χ2, Mann-Whitney e de McNemar, e a análise de regressão logística univariada. Resultados No carcinoma colorretal, as expressões da betacatenina e da adenomatous polyposis coli foram significativamente maiores do que em adenomas do colo (p<0,001 e p<0,0001, respectivamente). A imunorreatividade das proteínas GSK3β, axina 1 e ubiquitina foi significativamente maior (p=0,03, p=0,039 e p=0,03, respectivamente) no carcinoma colorretal do que no adenoma e na mucosa não neoplásica adjacente. A coloração imuno-histoquímica dessas proteínas não apresentou diferenças significantes em relação às características clinicopatológicas do câncer colorretal e do adenoma. Conclusões Em adenomas, as menores expressões de betacatenina, axina 1 e GSK3β indicaram que o complexo de destruição da betacatenina estava conservado, enquanto que, no carcinoma colorretal, o aumento das expressões da betacatenina, GSK3β, 1 axina, e ubiquitina indicaram que o complexo de destruição de betacatenina estava alterado.

EXPRESSION OF E-CADHERIN AND WNT PATHWAY PROTEINS BETACATENIN, APC, TCF-4 AND SURVIVIN IN GASTRIC ADENOCARCINOMA: CLINICAL AND PATHOLOGICAL IMPLICATION.

Background: Gastric cancer is the fifth most frequent cancer and the third most common cause of cancer-related deaths worldwide.It has been reported that Wnt/ betacatenin pathway is activated in 30-50% of these tumors. However,the deregulation of this pathway has not been fully elucidated. Aim: To determine the expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins in gastric adenocarcinoma tissues and correlate with clinical and pathological parameters. Method: Seventy-one patients with gastric adenocarcinoma undergoing gastrectomy were enrolled. The expression of E-cadherin, betacatenin, APC, TCF-4 and survivin proteins was detected by immunohistochemistryand related to the clinical and pathological parameters. Results: The expression rates of E-cadherin in the membrane was 3%; betacatenin in the cytoplasm and nucleus were 23,4% and 3,1% respectively; APC in the cytoplasm was 94,6%; TCF-4 in the nucleus was 19,4%; and survivin in the nucleus 93,9%. The expression rate of E-cadherin was correlated with older patients (p=0,007), while betacatenin with tumors <5 cm (p=0,041) and APC with proximal tumors (p=0,047). Moreover, the expression of TCF-4 was significantly higher in the diffuse type (p=0,017) and T4 tumors (p=0,002). Conclusion: The Wnt/betacatenin is not involved in gastric carcinogenesis. However, the high frequency of survivin allows to suggest that other signaling pathways must be involved in the transformation of gastric tissue.

Racional: O câncer gástrico encontra-se entre as principais neoplasias malignas do mundo sendo o quinto mais incidente e o terceiro em relação ao índice de mortalidade. Acredita-se que a via Wnt/betacatenina esteja ativada em 30-50% desses tumores, porém a desregulação dela ainda não está completamente esclarecida. Objetivo: Avaliar a imunoexpressão das proteínas E-caderina, betacatenina, APC, TCF-4 e survivina em tecidos de adenocarcinoma gástrico e correlacioná-las com as variáveis clínicas dos doentes e anatomopatológicas do tumor. Método: Foram coletados os dados clínicos e anatomopatológicos dos prontuários de 71 doentes com adenocarcinoma gástrico submetidos à gastrectomia. O material obtido na operação foi submetido à análise imunoistoquímica e a frequência da expressão de cada proteína pôde ser analisada de acordo com a sua localização na célula e relacionada com as variáveis clinicopatológicas. Resultados: A graduação percentualda expressão e da localização das proteínas foi a seguinte: E-caderina em 3% na membrana; betacatenina em 23,4% no citoplasma e 3,1% no núcleo; APC em 94,6% no citoplasma; TCF-4 em19,4% no núcleo; e survivina em 93,9% no núcleo. Houve relação entre expressão da proteína E-caderina com a idade mais avançada (p=0,007); betacatenina com tumores <5 cm de diâmetro (p=0,041);APC com tumores proximais (p=0,047); e TCF-4 com tipo difuso da classificação de Lauren (p=0,017) e com o grau de penetração tumoral (p=0,002). Conclusão: A via Wnt/betacatenina não está envolvida na carcinogênese gástrica. Porém, a frequência elevada de survivina permite sugerir que outras vias sinalizadoras devam estar envolvidas na transformação do tecido gástrico.

Genotoxicity and mutagenicity induced by acute crack cocaine exposure in mice.

CONTEXT: Crack cocaine is an illicit drug derived from cocaine, in which use and abuse have increased around the world, especially in developing countries. OBJECTIVES: The aim of this study was to evaluate genomic damage in multiple organs of mice following acute exposure to crack cocaine. For this purpose, single cell gel (comet) assay in peripheral blood, liver, kidney, and brain cells was performed and micronucleus test for bone narrow and liver cells was also made in this setting. MATERIAL AND METHODS: A total of 20 C57BL/10 male mice were distributed into four groups, as follows: 0, 4.5, 9, and 18 mg/kg b.w. of crack cocaine dissolved to 1% dimethyl sulfoxide by intraperitoneal (i.p.) route. All animals were sacrificed 24 h after i.p. injection. RESULTS: The results showed that crack cocaine induced DNA damage in peripheral blood, and brain cells for higher doses used as depicted by single cell gel (comet) assay data. Analysis of kidney cells showed no genetic damage for all groups tested. The number of micronucleated cells did not increase after crack cocaine exposure in bone narrow or liver cells. CONCLUSION: In summary, crack cocaine is a genotoxic agent in peripheral blood, liver, and brain cells but not mutagenic in multiple organs of mice.

Purple carrot extract protects against cadmium intoxication in multiple organs of rats: Genotoxicity, oxidative stress and tissue morphology analyses.

The aim of this study was to investigate if purple carrot extract is able to protect against the noxious activities induced by cadmium exposure in multiple organs of rats. For this purpose, histopathological analysis, genotoxicity and oxidative status were investigated in this setting. A total of twenty Wistar rats weighing 250g on the average, and 8 weeks age were distributed into four groups (n=5), as follows: Control group (non-treated group, CTRL); Cadmium group (Cd) and Purple carrot extract groups at 400mg/L or 800mg/L. Histopathological analysis revealed that liver from animals treated with purple carrot extract improved tissue degeneration induced by cadmium intoxication. Genetic damage was reduced in blood and hepatocytes as depicted by comet and micronucleus assays in animals treated with purple carrot extract. SOD-CuZn and cytocrome C gene expression increased in groups treated with purple carrot extract. Purple carrot extract also reduced the 8OHdG levels in liver cells when compared to cadmium group. Taken together, our results demonstrate that purple carrot extract is able to protect against cadmium intoxication by means of reducing tissue regeneration, genotoxicity and oxidative stress in multiple organs of Wistar rats.

Chemopreventive activity of grape juice concentrate (G8000TM) on rat colon carcinogenesis induced by azoxymethane.

Colorectal cancer is the third most common cancer worldwide in both sexes, with similar geographic patterns between genders. This neoplasm has good prognosis if the disease is diagnosed at early stages. The aim of this study was to evaluate the effect of red grape juice on the expression of COX-2 and Ki-67 expression following colon carcinogenesis induced by azoxymethane (AOM). Thirty-five rats were randomly distributed into seven groups (n=5 per group): G1: SHAM or negative control received only saline; G2 (positive control): animals received 15 mg/kg AOM; G3: animals received 1% red grape juice 2 weeks before the administration of AOM; G4: animals received 2% red grape juice 2 weeks before the administration of AOM; G5: animals received 1% red grape juice 4 weeks after the last administration of AOM; G6: animals received 2% red grape juice 4 weeks after the last administration of AOM; G7: animals received only 2% red grape juice. COX-2 mRNA expression was reduced in animals treated with 1% red grape juice before AOM induction or 2% red grape juice after AOM induction. COX-2 immunoexpression was also reduced to groups treated with red grape juice at 1% before and after AOM induction or 2% red grape juice after AOM induction. Decreased immunoexpression of Ki-67 positive cells was observed in animals treated with 1% grape juice before AOM-treated animals. Taken together, grape juice concentrate is able to exert some chemopreventive activity on rat colon carcinogenesis.

Antioxidant activity of apple extract protects against rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide.

Several studies have shown that apple (Malus sp.) has many components able to exert chemopreventive activity. The aim of this study was to evaluate the chemopreventive potential of apple extract following medium-term oral carcinogenesis assay induced by 4-nitroquinoline 1-oxide (4NQO) by means of histopathological analysis and gene expression of antioxidant enzymes, such as CuZnSOD, MnSOD and catalase. A total of 30 male Wistar rats were distributed into five groups, as follows (n = 6 per group): Group 1 - negative control group (non-treated group); Group 2 - received 4NQO during 8 weeks in drinking water and treated with apple extract by gavage between the 1st and 4th weeks daily (initiation phase); Group 3 - received 4NQO for 8 weeks in drinking water and treated with apple extract by gavage between the 5th and 8th weeks daily (promotion phase); Group 4 - received apple extract by gavage for eight consecutive weeks only; and Group 5 - received 4NQO for 8 weeks in drinking water daily. Histopathological analysis revealed that apple extract protect oral lesions induced by 4NQO at initiation or promotion phase. Higher gene expression of CuZnSOD and MnSOD enzymes were noticed in groups treated with apple extract as well. Taken together, our results demonstrate that the apple extract is able to modulate medium-term oral carcinogenesis assay as a result of antioxidant activity.