ABSTRACT
SUMMARY OBJECTIVE: This study aimed to determine the frequencies of Epstein-Barr virus, types 1 and 2 infection, and 30 bp del-latent membrane protein 1 viral polymorphism in gastric adenocarcinomas, as well as to investigate the association between Epstein-Barr virus infection and tumor location, type, and the patient's sex. METHODS: Samples were collected from 38 patients treated at a university hospital in Rio de Janeiro, Brazil. Epstein-Barr virus detection and genotyping were performed by polymerase chain reaction, followed by polyacrylamide gel electrophoresis and staining by the silver nitrate method. RESULTS: Overall, 68.4% of patients had Epstein-Barr virus-positive tumors. Of these, 65.4% presented infection by Epstein-Barr virus type 1, 23.1% by Epstein-Barr virus type 2, and 11.5% had coinfection with types 1 and 2. The 30 bp del-latent membrane protein 1 polymorphism was found in 42.3% of Epstein-Barr virus-positive tumors, 23.1% had the wild-type virus, and 23.1% had the wild-type and the polymorphism concomitantly. In 11.5% of Epstein-Barr virus-positive tumors, it was impossible to determine whether there was polymorphism or not. Tumor location in the antrum (22 of 38) and diffuse type (27 of 38) were predominant. There was no significant difference in Epstein-Barr virus infection or the 30 bp del-latent membrane protein 1 polymorphism between men and women. CONCLUSION: Epstein-Barr virus infection was found in 68.4% of tumors investigated in this study. To the best of our knowledge, this is the first article showing the coinfection of Epstein-Barr virus types 1 and 2 in gastric carcinoma in Brazil.
ABSTRACT
BACKGROUND: DNA methylation is commonly linked with the silencing of the gene expression for many tumor suppressor genes. As such, determining DNA methylation patterns should aid, in times to come, in the diagnosis and personal treatment for various types of cancers. Here, we analyzed the methylation pattern from five colorectal cancer patients from the Amazon state in Brazil for four tumor suppressor genes, viz.: DAPK, CDH1, CDKN2A, and TIMP2 by employing a polymerase chain reaction (PCR) specific to methylation. Efforts in the study of colorectal cancer are fundamental as it is the third most of highest incidence in the world. RESULTS: Tumor biopsies were methylated in 1/5 (20 %), 2/5 (40 %), 4/5 (80 %), and 4/5 (80 %) for CDH1, CDKN2A, DAPK, and TIMP2 genes, respectively. The margin biopsies were methylated in 3/7 (43 %), 2/7 (28 %), 7/7 (100 %), and 6/7 (86 %) for CDH1, CDKN2A, DAPK, and TIMP2, respectively. CONCLUSIONS: Our findings showed DAPK and TIMP2 to be methylated in most samples from both tumor tissues and adjacent non-neoplastic margins; thus presenting distinct methylation patterns. This emphasizes the importance of better understanding of the relation of these patterns with cancer in the context of different populations.
Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Colorectal Neoplasms/genetics , Genes, Tumor Suppressor , DNA Methylation/genetics , Brazil , Polymerase Chain Reaction , Promoter Regions, Genetic , Gene SilencingABSTRACT
OBJETIVO: Estudar a ação do álcool perílico na expressão gênica de células de adenocarcinoma de pulmão humano. MÉTODOS: Incubaram-se células de adenocarcinoma de pulmão com álcool perílico em diluições que variaram entre 0,03 por cento e 0,0003 por cento por 48 horas. Observaram-se as alterações na morfologia celular e quantificou-se a viabilidade celular pelo método do MTT (3-(4,5-dimetiltiazol-2-yl)-2,5 difeniltertrazolim brometo). Analisou-se a síntese de proteínas das amostras previamente marcadas radioativamente com 35S, através de eletroforese em gel de poliacrilamida. Determinou-se a expressão das proteínas p53 e p42/44 através do método de Western Blot. RESULTADOS: Após 48 horas de incubação, observaram-se alterações na morfologia celular para a diluição de 0,03 por cento de álcool perílico, as quais foram pouco verificadas em diluições superiores a 0,003 por cento. A inibição da viabilidade celular foi de 60,17 por cento (p < 0,001), 15,62 por cento (p < 0,001) e 11,53 por cento (p < 0,05) para as diluições de 0,03 por cento, 0,003 por cento e 0,0003 por cento de álcool perílico, respectivamente. Os resultados mostram a indução de proteínas de 110 kDa, 42 kDa e 28 kDa. Não se observou variação estatisticamente significativa para a expressão da proteína p53. Em comparação com a expressão de alfa-tubulina, a diluição de 0,003 por cento de álcool perílico provocou uma diminuição marcante da fosforilação da p44 e um aumento da fosforilação da p42. CONCLUSÃO: Os resultados apresentados sugerem novos caminhos metabólicos da ação do álcool perílico em células de adenocarcinoma de pulmão humano.
OBJECTIVE: To study the effect of perillyl alcohol on the gene expression of human pulmonary adenocarcinoma cells. METHODS: Pulmonary adenocarcinoma cells were incubated with perillyl alcohol in dilutions ranging from 0.03 percent to 0.0003 percent for 48 hours. Alterations were observed in the cell morphology, and cell viability was quantified using [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assays. Protein synthesis of samples previously targeted with S35 was analyzed using electrophoresis on a polyacrylamide gel. Expression of the proteins p53 and p44/42 was determined using the Western blot method. RESULTS: After 48 hours of incubation, greater nsumbers of morphological alterations were observed in cells treated with the 0.03 percent perillyl alcohol dilution than in those treated with perillyl alcohol diluted to 0.003 percent or further. Treatment with perillyl alcohol dilutions of 0.03 percent, 0.003 percent and 0.0003 percent inhibited cellular viability by 60.17 percent (p < 0.001), 15.62 percent (p < 0.001) and 11.53 percent (p < 0.05), respectively. The results show that 28-kDa, 42-kDa and 110-kDa proteins were induced. No statistically significant effect on p53 expression was observed. In comparison with the expression of alpha-tubulin, the 0.003 percent perillyl alcohol dilution induced an increase in p42 phosphorylation and a marked decrease in p44 phosphorylation. CONCLUSION: The results suggest that there are other, previously undescribed, metabolic pathways for perillyl alcohol effects in human pulmonary adenocarcinoma cells.