RESUMO
Although the B-cell translocation gene 1 (BTG1) plays an important role in apoptosis and negatively regulatescell proliferation, BTG1 expression in skin squamous cell carcinoma (SCC) has not been reported. In this study,we wanted to investigate the significance of BTG1 expression in SCC and adjacent tissues. The expression ofBTG1 protein and mRNA in SCC tissues and adjacent tissues were detected by immunohistochemistrytechnique (IHC), Western blot and reverse transcriptase-polymerase chain reaction (RT-PCR). IHC stainingshowed that the positive expression rate of BTG1 protein in SCC tissues was 54.00%; and the positive rate was90.50% in the adjacent tissues. Western blot showed that the expression of BTG1 protein in SCC tissues wassignificantly lower than that in the adjacent tissues (P\0.05). RT-PCR showed that the positive rate of BTG1mRNA in SCC was 50.50%, which was significantly lower than that in adjacent tissues 89.00% (P\0.05).Both BTG1 mRNA and protein expression are related to tumor diameter, stage, tumor metastasis and thedegree of tumor differentiation in SCC. Patients exhibiting lower BTG1 protein expression in the SCC tissueshad a significantly shorter disease-specific survival rate. BTG1 protein expression, tumor diameter, tumors siteand stage were independent factors affecting the overall survival of postoperative patients. Further, BTG1overexpression inhibited A431 cell proliferation ability, while BTG silencing enhanced A431 cell proliferationability. The lower expression of BTG1 in SCC may be associated with the occurrence, development andprognosis of SCC.
RESUMO
Introducción: en otros países se han descrito ciertos factores relacionados con el desarrollo de queratosis actínica (QA). Objetivo: describir las características clínicas, epidemiológicas e histopatológicas de pacientes institucionales de Medellín, con diagnóstico de QA. Metodología: estudio descriptivo de pacientes con QA. Se aplicó una encuesta estructurada tomando datos demográficos, clínicos y relacionados con el desarrollo de la QA. Resultados: se incluyeron 153 pacientes (58 hombres [37,9%] y 95 mujeres [62,1%]), con edad promedio de 70 años. Tenían 75 años o más 64 pacientes (41,8%). Ciento ocho pacientes (70,6%) refirieron haber tenido un grado alto de exposición solar en la niñez; 76 (49,7%) tenían el antecedente de fumar y 16 de estos (21,1%) aún fumaban; 46 (30,1%) informaron el antecedente de un familiar con cáncer de piel. Setenta y tres (47,7%) realizaban las actividades tanto bajo techo como al aire libre; 80 (52,3%) informaron que se aplicaban protector solar y 37 (24,4%) usaban gorra o sombrero por la época en que fueron encuestados. Predominó el fototipo II (101 pacientes; 66%) y había daño actínico moderado en 76 (49,7%). Cuando hubo un solo patrón histológico predominó el atrófico (12%) y cuando hubo dos, el atróficohiperqueratósico (18,7%). Conclusiones: las características fenotípicas y de exposición de los pacientes con QA estudiados en Medellín (Colombia) son similares a las reportadas en la literatura.
Introduction: Several factors related with the development of actinic keratosis (AK) have been reported in other countries. Objective: To describe the clinical, epidemiological and histopathological characteristics of patients with diagnosis of AK in Medellín, Colombia. Methodology: This was a descriptive study of patients with AK. A structured survey including demographic, clinical and epidemiological information was applied. Results: 153 patients were included (58 men [37.9%] and 95 women [62.1%]) with an average age of 70 years. Sixty four patients (41.8%) were aged 75 years or more. With regard to their personal history, 108 individuals (70.6%) had a high degree of solar exposure during childhood; 76 (49.7%) reported the habit of smoking and 16 out of these (21.1%) still smoked. In 46 (30.1%) there was a family history of skin cancer. Regarding individual habits, 73 (47.7%) carried out both indoor and outdoor activities, 80 (52.3%) reported the use of sunscreen and 37 (24.4%) used hat or cap at the time of the study. Fitzpatrick´s type II phototype predominated (101 patients; 66%) and 76 (49.7%) had moderate actinic damage. The predominant single histologic subtype corresponded to the atrophic type (12%) and the main mixed subtype was the atrophichyperkeratotic subtype (18.7%). Conclusions: Clinical, epidemiological and histopathological features found among two institutional populations with AK in Medellin (Colombia) were similar to those reported in the literature.