RESUMO
En Chile, el cáncer es la segunda causa de muerte después de las enfermedades cardiovasculares. Los principales cánceres asociados a muerte en mujeres fueron mama, estómago, vesícula biliar, broncopulmonar y cérvico uterino. Alteraciones de las E-cadherinas han sido relacionadas con varios tipos de cáncer, ya que uno de los principales eventos involucrados con su disfunción es el gatillar la invasión y metástasis del tumor. La inactivación del gen CDH1 ha sido demostrada en el cáncer gástrico difuso y el cáncer de mama lobulillar. Asimismo, la inactivación del gen FHIT parece estar asociado con la progresión a neoplasias más agresivas. Se realizaron determinaciones inmunohistoquímicas (IHQ) en fibroadenomas mamarios y cánceres previamente diagnosticados por RE, RPg y Her2, mostrando positividad en todos los casos. La detección (IHQ) de la expresión de FHIT y E-cadherina en tejidos con patologías benignas y malignizados, puede aportar una importante información diagnóstica y pronóstica en el cáncer de mama.
In Chile, cancer is the second leading cause of death after cardiovascular diseases. The major death-related cancers in women were breast, stomach, gallbladder, lung and cervical cancer. Alterations of E-cadherin have been linked to various cancers, as one of the main events involved in its dysfunction is the trigger of tumor invasion and metastasis. CDH1 gene inactivation has been demonstrated in diffuse gastric cancer and lobular breast cancer. Furthermore, inactivation of the FHIT gene to be associated with progression to more aggressive tumors. Immunohistochemistry (IHC) determinations were performed in fibroadenomas and breast cancers previously diagnosed by ER, PgR and Her2, showing positivity in all cases. Immunohistochemical detection of FHIT and E-cadherin expression in tissues with benign disease and malignant, may provide an important diagnostic and prognostic information in breast cancer.
Assuntos
Humanos , Feminino , Hidrolases Anidrido Ácido/metabolismo , Caderinas/metabolismo , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/diagnóstico , Carcinoma Lobular/metabolismo , Fibroadenoma/diagnóstico , Fibroadenoma/metabolismo , Imuno-HistoquímicaRESUMO
Background: The loss of tumor suppresor gene function damages the defensive mechanisms that protect the indemnity of genetic material. Promoter gene methylation is one of the inactivation mechanisms of suppressor genes. Aim: To study the methylation pattern of a group of genes in biopsy samples of gastrointestinal tumors. Material and methods: Forty eight gastric, 25 gallbladder, 24 colon and 6 pancreas cancer biopsy samples were randomly selected. The methylation pattern of CDH1, FHIT, CDKN2A, APC and MLH1 genes, was studied using a specific polymerase chain reaction test for methylation. Demographic, morphological and follow up variables of patients bearing the tumors were also analyzed. Results: The general methylation frequency of CDH1, FHIT, CDKN2A, APC and MLH1 genes was 64.1, 56, 39.8, 18.1 and 34 percent respectively. In gastric cancer samples there was a correlation between APC gene methylation and well differentiated tumors; between CDH1 methylation and Lauren diffuse type and the presence of three or more metastasic lymph nodes; between FHIT, CDKN2A and CDH1 gene methylation and male gender. In ¡ess differentiated gallbladder tumors, the frequency of CDH1 methylation was higher. There was a tendency towards a lower survival in colon and gastric cancer when MLH1 (p =0.07) y CDKN2A (p= 0.06) were methylated, respectively. Conclusions: An abnormal methylation pattern was associated with morphological features in gastric and gallbladder cancer and with a tendency towards a lower survival in colon and gastric cancer.