Navegando por Assunto "Biomarcadores tumorais"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Homocisteína vitamina B12 e ácido fólico como biomarcadores de triagem no diagnóstico precoce e monitoramento do câncer gástrico
(Universidade Federal do Pará, 2018-10-11) ALCÂNTARA, Fernanda Farias de; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Gastric cancer in the last decades has shown a decrease in the number of cases, which is much due to the progress in sanitary health, and the greater access of the population to educational policies. However, it remains the third leading cause of death worldwide between men and women. Such deaths are usually linked to late diagnosis. The present study intends to establish a profile of screening biomarkers by the homocysteine, vitamin B12 and folic acid dosages, which can be inserted in the routine routine of examinations, aiming the rapid diagnosis of the disease. A total of 207 control and 207 cases of gastric cancer patients were analyzed, both of which were biochemical measurements of homocysteine, folic acid and vitamin B12, matched in relation to age, tumor location, subtype, tumor classification, EBV (Epstein-Barr Virus), and Helicobacter pylori. For the triad dosage, chemiluminescence techniques were used, and the other variables were obtained by hospital information. As results, significant differences were found between the means of the triad of cancer patients in relation to the control, in all paired variables. In conclusion, our study showed that the triad analysis (homocysteine, vitamin b12 and folic acid) has its value in the diagnosis of gastric cancer, and may in the future be an effective marker of screening for this type of cancer.
Acesso aberto (Open Access)
Significado da expressão de p16INK4A e da perda de heterozigosidade do gene PTEN no carcinoma epidermóide bucal relacionado ao papilomavírus humano
(Universidade Federal do Pará, 2023-06) KATO, Valdenira de Jesus Oliveira; ALCÂNTARA, Diego Di Felipe Ávila; http://lattes.cnpq.br/1794240697748468; https://orcid.org/0000-0001-5045-2265; BURBANO, Rommel Mario Rodríguez; http://lattes.cnpq.br/4362051219348099; https://orcid.org/0000-0002-4872-234X
The p16 and PTEN genes are part of the family of tumor suppressor genes commonly associated with the inactivation of a variety of human cancers. The loss of its expression has been studied worldwide in oral squamous cell carcinoma (OSCC). In this study, we evaluated the hypothesis that p16 cooperates with inactive PTEN during OSCC pathogenesis, especially in tumor aggressiveness and proliferation. For that, 119 OSCC samples were used in which the relationship between HPV infection, p16 expression and PTEN mutations were evaluated throug himmunohistochemistry (IHC), western blot, immunofluorescence and sequencing techniques. The results of this study demonstrated that PTEN has high positivity in patients with more advanced tumor size (p < 0.01) and lymph node metastasis (p = 0.02). Statistical analysis showed that p16 expression was strongly associated with the presence of HPV (p<0.0001), but that its aberrant expression is not related to altered PTEN (p=0.52). It was also observed that 60% of the samples in stage IV (advanced stage of the tumor) were statistically associated with the presence of mutation. It is concluded that PTEN and p16 are suppressor genes that control tumor progression. In the current study, PTEN showed great erreactivity in advanced stages of the disease (greater than seven times). p16 was strongly associated with HPV, but did not show a significant association with any clinical-pathological factor analyzed. Both proteins are of great importance in the prognosis of patients. Viral presence has been shown to decrease tumor aggressiveness. Lesions in advanced stages have a shorter survival, in addition, the presence of mutation was more commonly observed in advanced stages of the disease. It was observed that smoking patients witht he absenceof p16 are significantly associated with a survival rate twice as low.