Celecoxib: Antiangiogenic and Antitumoral Action / Celecoxib: Acción Antiangiogénica y Antitumoral

SUMMARY: Angiogenesis, a process by which new blood vessels are generated from pre-existing ones, is significantly compromised in tumor development, given that due to the nutritional need of tumor cells, pro-angiogenic signals will be generated to promote this process and thus receive the oxygen and nutrients necessary for its development, in addition to being a key escape route for tumor spread. Although there is currently an increase in the number of studies of various anti-angiogenic therapies that help reduce tumor progression, it is necessary to conduct a review of existing studies of therapeutic alternatives to demonstrate their importance.

La angiogénesis, proceso por el cual se generan nuevos vasos sanguíneos a partir de otros preexistentes, se encuentra comprometida de forma importante en el desarrollo tumoral, dado que por necesidad nutritiva de las células tumorales se generarán señales pro angiogénicas para promover este proceso y así recibir el oxígeno y los nutrientes necesarios para su desarrollo, además de ser una ruta de escape clave para la diseminación tumoral. Si bien, actualmente existe un aumento en la cantidad de estudios de diversas terapias anti angiogénicas que ayudan a reducir el avance tumoral, es necesario realizar una revisión de los estudios existentes de alternativas terapéuticas para demostrar su importancia.

Patrón de metilación génico en el cáncer de mama / Promoter methylation profile in breast cancer

BACKGROUND: Genomic DNA methylation, mutations and allelic deletions explain the inactivation of genes involved in cell proliferation and cell cycle control mechanisms. AIM: To analyze the methylation pattern of important genes related to different carcinogenic mechanisms in patients with breast cancer and the relationship with its biological behavior. MATERIAL AND METHODS: Seventy fresh-frozen breast cancer samples were selected. The methylation specific PCR (MSP) test was used to analyze promoter methylation status for genes CDKN2A (p16), hMLH1, APC, CDH1 (Cadherin E) and FHIT. RESULTS: We found methylation in at least one of the genes studied in 88% of cases and in 3 or more genes in 40.5% of cases. The frequencies of promoter hypermethylation of CDKN2A, hMLH1, APC, CDH1 and FHT were 41.4%, 11.4%, 52.9%, 70% and 42.9%, respectively. We found a relationship between CDKN2A methylatlon and better survival (p=0.002). CDH1 methylation and poor histological differentiation (p=0.007), hMLH1 methylation and non-Mapuche ethnicity (p=-0.03), APC methylation and larger tumor size (p<0.05), FHIT methylatton and lack of estrogen rectptor IHC expression (p<0.05). CONCLUSIONS: The high frequency of promoter methylation in patients with breast cancer confirms its role in breast carcinogenesis. The finding of alterations in the methylation pattern of genes studied and its association with prognostic factors is a helpful tool in the search of new criteria for clinical and therapeutic decision making.

Carcinoma subseroso de la vesícula biliar: expresión del complejo caderina-catenina / Subserous gallbladder carcinoma: expression of cadherine-catenine complex

BACKGROUND: Subserous gallbladder carcinoma is difficult to diagnose and treat. There are no tissue markers with prognostic value in this type of tumor. AIM: To study the immunohistochemical expression of E-cadherin alpha and beta catenin in subserous gallbladder carcinoma. PATIENTS AND METHODS: One hundred seventeen subjects (103 women and 14 men aged 62 and 69 years as a mean, respectively), were studied. Thirty five gallbladder samples without evidence of cancer were used as controls. Expression of markers was studied with standard immunohistochemical techniques for formalin fixed and paraffin embedded tissue. RESULTS: Ninety seven percent of tumors were adenocarcinoma. A lower or absent expression of E-cadherin, alpha catenin and beta catenin was observed in 26, 33 and 29 per cent, respectively. Actuarial five years survival was 37 per cent. No association between macroscopic features of the tumor and survival was observed. Well differentiated tumors had a 73 per cent survival, whereas less differentiated tumors had a 30 per cent survival. Tumors with a normal expression of the markers had a slightly better survival, although not significant (p = 0.06). CONCLUSIONS: Approximately 30 per cent of subserous gallbladder carcinoma have an abnormal expression of E-cadherin, alpha catenin and beta catenin. This abnormal expression has no relationship with prognosis and is probably secondary to the aberrant genic expression of the tumor.

Cáncer vesicular: manejo de estadios potencialmente curativos / Gallbladder cancer: management of potentially curables types

Desde mayo de 1988, 35 pacientes con formas potencialmente curables de un cáncer vesicular, han sido tratadas en nuestro Departamento. Del total de pacientes, en sólo 4 el diagnóstico fue sospechado durante el intraoperatorio, mientras que en los restantes éste fue efectuado luego de la observación macrocópica de la pieza o del estudio histopatológico. Como parte de nuestro protocolo, a aquellos pacientes con un tumor que invadía la túnica muscular o la subserosa se les planteó la posibilidad de efectuarles una reintervención con el fin de practicar la resección del lecho vesicular y una linfadenectomía. De los pacientes, 4 rechazaron la intervención, en 2 existieron causas médicas que contraindicaron la reintervención, mientras que en 4 la enfermedad se consideró incurable al momento de la reintervención. De los 7 pacientes con compromiso seroso, sólo 4 puedieron ser resecados debido a que 1 rehusó ser intervenido mientras que los dos restantes tenían compromiso tumoral fuera de los límites de la resección al momento de la reintervención. En relación a las intervenciones practicadas, en 18 pacientes efectuamos una colecistectomía extendida, en dos una bisegmentectomía hepática asociada a la resección de la vía biliar mientras que en una paciente efectuamos una pancreatoduodenectomía