Michele Conceição Pereira

Recurrent peripheral odontogenic keratocyst: a case report

A case of peripheral odontogenic keratocyst arising in a 57-year-old white female patient involving the posterior mandibular gingiva that recurred after 12 months of follow-up is presented. This reported case reinforces that patients presenting peripheral odontogenic keratocyst should be carefully followed up after conservative surgical treatment.

Eosinophil Cationic Protein: Overview of Biological and Genetic Features

The eosinophil cationic protein (ECP) is a small polypeptide that originates from activated eosinophil granulocytes. A wide range of stimuli has been shown to induce the secretion of ECP. The gene that encodes the human ECP is located on chromosome 14, and the protein shares the overall three-dimensional structure and the RNase active-site residues with other proteins in the RNase A superfamily. Several single-nucleotide polymorphisms in the human ECP gene have been currently described. ECP has many biological functions, including an immunoregulatory function, the regulation of fibroblast activity, and the induction of mucus secretion in the airway. Additionally, the protein is a potent cytotoxic molecule and has the capacity to kill mammalian and nonmammalian cells. The purpose of this article was to review the known biological and genetic characteristics of ECP that contribute to the understanding of this proteins role in the development and progression of a wide variety of diseases.

The 434(G>C) polymorphism in the eosinophil cationic protein gene and its association with tissue eosinophilia in oral squamous cell carcinomas

OBJECTIVE The aim of this study was to investigate the prevalence of the Eosinophil cationic protein (ECP)-gene polymorphism 434(G>C) in oral squamous cell carcinoma (OSCC) patients and its association with tumor-associated tissue eosinophilia (TATE), demographic, clinical, and microscopic variables. METHODS The ECP genotypes of 165 healthy individuals and 157 OSCC patients were detected by PCR-RFLP analysis after cleavage of the amplified DNA sequence with enzyme PstI. TATE was obtained by morphometric analysis. Chi-square test or Fishers exact test was used to analyze the association of ECP-gene polymorphism 434(G>C) with TATE, demographic, clinical, and microscopic variables in OSCC patients. Disease-free survival and overall survival were calculated by the Kaplan-Meier product-limit actuarial method and the comparison of the survival curves were performed using log rank test. RESULTS Most of healthy individuals (53.33%) and OSCC patients (57.97%) were heterozygous for the ECP 434(G>C) polymorphism. Based on numerical differences, our results showed that OSCC patients with intense TATE and at least one C allele had a higher frequency of bilateral neck dissection, local recurrence, vascular embolization, involved resection margins, and postoperative radiotherapy. No statistically significant differences on survival rates were found in OSCC patients presenting different ECP 434(G>C) genotypes. CONCLUSIONS These results suggest a tendency towards a poor clinical outcome in OSCC patients with intense TATE and 434GC/CC genotypes, probably due to an ECP genetic variant with altered cytotoxic activity.

Associação do polimorfismo do gene da proteína catiônica eosinofílica com a eosinofilia tecidual associada aos tumores em carcinomas espinocelulares de boca

A proteina cationica eosinofilica (ECP) presente nos grânulos especificos dos eosinofilos apresenta atividade citotoxica, particularmente para celulas tumorais, entretanto a funcao exata dos eosinofilos e de seus produtos nas neoplasias malignas continua obscura. O objetivo desse trabalho foi investigar a prevalencia do polimorfismo 434(G>C) do gene ECP em pacientes com carcinoma espinocelular (CEC) de boca e sua correlacao com a eosinofilia tecidual associada aos tumores (TATE), bem como com as caracteristicas demograficas, clinicas e microscopicas. O genotipo 434 do gene ECP em 165 pacientes saudaveis e em 157 pacientes com CEC de boca, tratados no Hospital do Câncer A. C. Camargo entre 1984 a 2002, foi detectado pela clivagem da sequencia especifica de DNA amplificada com a enzima de restricao PstI e analise dos produtos de clivagem pela eletroforese em gel de agarose. A TATE foi determinada por analise morfometrica. A associacao entre os genotipos, a intensidade da TATE e as variaveis demograficas, clinicas e microscopicas foi avaliada pelo teste qui-quadrado ou teste exato de Fisher. As analises das sobrevidas global, livre de doenca e especifica por câncer foram feitas pelo estimador limite de Kaplan-Meier e a comparacao das curvas de sobrevida foi realizada utilizando-se o teste log-rank. Notou-se uma predominância dos individuos heterozigotos para o polimorfismo 434(G>C) do gene ECP. Nenhuma diferenca estatistica significativa foi obtida entre os diferentes genotipos, a intensidade da TATE e as variaveis demograficas, clinicas e microscopicas. Uma maior frequencia de esvaziamento cervical bilateral, recidiva local, embolizacao vascular, comprometimento das margens cirurgicas e realizacao de radioterapia pos-operatoria foi observada nos pacientes com CEC de boca, TATE intensa e genotipos 434GC/CC. Nao houve correlacao estatistica significativa entre os diferentes genotipos 434 do gene ECP e as sobrevidas global, livre de doenca e especifica por câncer. Baseados em nossos resultados, concluimos que houve uma tendencia de os pacientes com CEC de boca, intensa eosinofilia tecidual e genotipos 434GC/CC do gene ECP apresentarem uma evolucao clinica desfavoravel, quando comparados aos individuos com genotipo 434GG, provavelmente pela presenca de uma variante genetica dessa proteina com propriedades citotoxicas alteradas. Eosinophil cationic protein (ECP), found in secretory granules of human eosinophils, presents cytotoxic activity, particularly against cancer cells. The specific functional role of eosinophils in solid malignant tumors remains unclear. The aim of this study was to investigate the prevalence of the ECP-gene polymorphism 434(G>C) in oral squamous cell carcinoma (OSCC) patients and its association with tumor-associated tissue eosinophilia (TATE), as well as demographic, clinical and microscopic variables. The 434 genotypes in the ECP-gene of 165 healthy individuals and 157 OSCC patients, submitted to surgical treatment at the Hospital A. C. Camargo from 1984 to 2002, were detected by cleavage of the amplified DNA sequence with restriction enzyme PstI and analyses of the cleaved product by agarose gel electrophoresis. TATE, in OSCC, was obtained by morphometric analysis. Chisquare test or Fisher’s exact test was used to analyze the association among ECP-gene polymorphism 434(G>C), TATE, demographic, clinical and microscopic variables. Diseasefree survival and overall survival were calculated by the Kaplan-Meier product-limit actuarial method and the comparison of the survival curves were performed using log rank test. Most of healthy individuals and OSCC patients showed the genotype 434GC. There was no statistical association among 434 genotypes, TATE intensity and demographic, clinical or microscopic variables of OSCC patients. Higher frequency of bilateral neck dissection, local recurrence, vascular embolization, involved resection margins and postoperative radiotherapy was detected in OSCC patients with intense TATE and 434GC/CC genotypes. No statistically significant differences on survival rates were found among 434 genotypes. In conclusion, these results suggest a tendency of worse clinical outcome in OSCC patients with intense TATE and 434GC/CC genotypes, probably due an ECP genetic variant with altered cytotoxic activity.