ABSTRACT
El polimorfismo del codón 72 del gen TP53 ha sido asociado con un riesgo elevado para el desarrollo de cáncer. Este polimorfismo origina dos variantes de la proteína, una con un residuo de Arginina (CGC), y otra con Prolina (CCC). El objetivo del estudio fue analizar la asociación de este polimorfismo con el riesgo de desarrollar cáncer gástrico en individuos procedentes de la región centroccidental de Venezuela, considerada de alto riesgo para esta neoplasia maligna. El ADN fue extraído de biopsias de adenocarcinoma gástrico incluídas en parafina (n = 65) y biopsias endoscópicas de pacientes con gastritis crónica (n = 87). El polimorfismo del codón 72 de TP53 fue determinado por PCR-RFLP. Se observó un incremento significativo de la frecuencia del alelo Arg en los pacientes con cáncer gástrico (P = 0,037), originando un riesgo 4,6 veces mayor (95% IC 1,0-21,3) de desarrollar esta enfermedad. Se evidenció un incremento del genotipo Arg/Arg en adenocarcinoma gástrico poco diferenciado (OR: 3,1; 95% IC 1,0-9,2), y del genotipo Arg/Pro en adenocarcinoma de moderado/buen grado de diferenciación (OR: 3,5; 95% IC 1,1-11,0) al comparar con el grupo de cáncer gástrico, y este último también al contrastar con los individuos con gastritis crónica (OR: 2,4; 95% IC 1,1-5,2). Los resultados de este estudio sugieren que la condición de portador del alelo Arg podría estar asociado con el desarrollo de cáncer gástrico en esta región de Venezuela.
Codon 72 polymorphism of the tumor suppressor gene TP53 has been associated with a higher risk in the development of several types of cancer. The polymorphism results in a variant protein with either an arginine (CGC) or a proline residue (CCC). The aim of this study was to analyze the association of the TP53 codon 72 polymorphism with the risk of developing gastric cancer in a high-risk population from the central-western region of Venezuela. DNA was extracted from paraffin-embedded gastric adenocarcinoma biopsies (n = 65) and endoscopic biopsies from chronic gastritis patients (n = 87). TP53 codon 72 polymorphism was determined by PCR-RFLP from all samples. Patients with gastric cancer had a significantly higher frequency (P = 0.037) of the Arg allele than those with chronic gastritis. A logistic regression analysis suggested that Arg carrier individuals had a 4.6-fold higher risk (95% CI 1.0-21.3) of developing gastric cancer. An increment of the Arg/Arg genotype was observed in poor-differentiated gastric adenocarcinoma (OR: 3.1; 95% CI 1.0-9.2), and of the Arg/Pro genotype in well/ moderate-differentiated adenocarcinoma samples (OR: 3.5; 95% CI 1.1-11.0), when comparing within the gastric cancer samples; and the last group also when contrasting it with chronic gastritis patients (OR: 2.4; 95% CI 1.1-5.2). The results of this study suggest that the carriage of the Arg allele could be associated with the development of gastric cancer in this Venezuelan population.
Subject(s)
Humans , Male , Female , Adenocarcinoma/pathology , Biopsy/methods , Codon/adverse effects , Polymorphism, Genetic , Stomach Neoplasms , Medical OncologyABSTRACT
Background: Genetic predisposition may play a role in the prevalence of gastric cancer (GC). Aim: To investigate the relationship between selected interleukin-1 (IL-1) loci polymorphisms and gastric cancer risk in the Central-Western region of Venezuela, where gastric cancer represents the first cause of cancer-related deaths. Material and methods: In a case-control study, we compared the frequencies of IL-1B-511 and IL-1B+3954 biallelic polymorphism, and the pentallelic VNTR of IL-IRN in 84 gastric adenocarcinoma paraffin-embedded biopsies and 84 endoscopic biopsies from cancer-free controls. Results: No significant increase in genotypic frequencies in gastric cancer was observed for any of the IL-1B-511 allelic combinations. However, in alogistic regression analysis, a significant association emerged for the IL- 1B+3954C carrier genotype (odds ratio (OR): 6.2; 95% confidence intervals (CI) 1.3-28.8). On the other hand, a significantly higher risk was evidenced for the IL-IRN*2/*2 genotype (OR: 7.0; 95% CI 2.3-21.5). Only patients with awell/moderately-differentiated adenocarcinoma that were homozygotes for the IL-IRN*2/*2 genotype, had a higher risk than the complete gastric cancer group (OR: 8.1, 95% CI 2.5-26.8). Some genotype combinations among IL-1B-511, IL-1B+3954 and IL-IRN showed an increased risk for developing gastric cancer and well/moderate differentiated adenocarcinoma, that was dependent of the presence of IL-IRN*2/*2 genotype. Conclusions: IL-IRN*2/*2 genotype is associated with increased risk of gastriccancer in the Venezuelan population.
Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Young Adult , Adenocarcinoma/genetics , Genetic Predisposition to Disease , Interleukin-1/genetics , Polymorphism, Genetic , Stomach Neoplasms/genetics , Adenocarcinoma/pathology , Case-Control Studies , Gene Frequency , Odds Ratio , Risk Factors , Stomach Neoplasms/pathology , Venezuela , Young AdultABSTRACT
El objetivo del estudio fue determinar los niveles séricos de zinc en una población rural menor de 15 años del estado Lara-Venezuela, con el fin de conocer las deficiencias en este oligoelemento y emprender a través de los organismos competentes la intervención nutricional. Se estudiaron 310 niños (M:163; F:147) menores de 15 años, con edad promedio de 86,39 meses. El zinc sérico se midió por espectrofotometría de absorción atómica. El nivel sérico de zinc fue de 0,83 ± 0,18 μg/ml. Se observó deficiencia de zinc (valores ≤ 0,72 μg/ml) en 19,7 por ciento de los niños, siendo los menores de 2 años los más afectados. Asimismo, se observó un mayor porcentaje de deficiencia de zinc en niños con déficit nutricional seguidos por aquellos que tenían un estado nutricional normal. Al distribuir los deficientes de zinc por grupo de edad y estado nutricional se observó que el 55,6 por ciento de los menores de 2 años tenía un estado nutricional normal y otro 44,4 por ciento presentó déficit nutricional, mientras que más del 70 por ciento de los deficientes de zinc en los grupos de edades de 2-6 y 7-14 años mostraron un estado nutricional normal. Todos los niños con deficiencia pertenecían a familias con pobreza extrema. En vista de las consecuencias negativas que implica la carencia de zinc, es necesario realizar un diagnóstico más preciso de su deficiencia a través de métodos indirectos como el test de tolerancia de zinc o suplementación oral de zinc, para identificar poblaciones en riesgo de deficiencia de zinc. Asimismo, iniciar programas de intervención con este oligoelemento, especialmente en la población infantil vulnerable, como las que aquí habitan.
The aim of this research was to determine the levels of serum zinc in a rural population under 15 years old, in Lara State, Venezuela, in order to know the deficiencies of this oligoelement and start the nutritional intervention by the involved organizations. The sample was made up of 310 subjects (M: 163; F: 147) under 15 years old, with an average age of 86.39 months. The serum zinc was measured by atomic absortion spectrophotometry. The serum zinc level was 0.83 ± 0.18 μg/ml. Deficiency of zinc (values = 0.72 μg/ml) was presented in 19.7% of the subjects; the most affected were those under two years old. Likewise, the highest percentage of zinc deficiency was observed in subjects with nutritional deficit followed by those that had a normal nutritional condition. By splitting the group of subjects with zinc deficiencies by age and nutritional condition, it was observed that 55.6% of those under two years old had a normal nutritional condition and the remaining 44.4% showed nutritional deficiency. Meanwhile, more than 70% of the subjects with zinc deficiency belonging to the groups aged 2-6 and 7-14 showed a normal nutritional condition. All the subjects with nutritional deficit belonged to families living in extreme poverty. Due to the negative consecuences that imply the lack of zinc, it is necessary to make a more accurate diagnosis of its deficiency through indirect methods like the zinc tolerance test or oral supplementation of zinc, in order to identify population with risk of zinc deficiencies. Likewise, to start intervention programs with this oligoelement, especially in the vulnerable child population like the one studied.