ABSTRACT
BACKGROUND AND AIM: Hepatocellular carcinoma (HCC) is the most common primary liver cancer diagnosed worldwide. Deregulation of Wnt/beta-catenin pathway has been associated with the development of HCC in a substantial number of cases in Europe and far less in Asia. Nothing is known about this pathway in HCC cases from South America. This study aimed to investigate the frequency of mutations in beta-catenin gene (CTNNB1) and the subcellular localization of beta-catenin in HCC cases from Colombia. MATERIAL AND METHODS: We determine by direct sequencing the frequency of mutations in exon 3 of CTNNB1 gene and by immunohistochemistry the subcellular localization of beta-catenin in 54 samples of HCC obtained from three pathology units in Bogota and Medellin cities. RESULTS: Only three HCC cases (5.6%) were found mutated at residues (G34E, S45P, P44S, T41I) important for phosphorylation and ubiquitination of beta-catenin protein. Strikingly, nuclear or cytoplasmic accumulation of beta-catenin, hallmark of Wnt pathway activation, was found in 42.6% HCC cases (23/54). Interestingly, beta-catenin accumulation was significantly more frequent in young patients and hepatitis B virus-related HCC. CONCLUSIONS: Although, CTNNB1 exon 3 mutations are not frequent in HCC from Colombian patients, our findings indicate that Wnt/beta-catenin signaling is activated in 42.6% of HCC samples. Furthermore, Wnt signaling was demonstrated in HCC cases associated of HBV infection, one of the most important HCC risk factors in Colombia.
Subject(s)
Carcinoma, Hepatocellular/genetics , Liver Neoplasms/genetics , Mutation , Wnt Signaling Pathway/genetics , beta Catenin/genetics , Age Factors , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/etiology , Carcinoma, Hepatocellular/pathology , Cohort Studies , Colombia , Exons , Female , Hepatitis B, Chronic/complications , Humans , Immunohistochemistry , Liver Neoplasms/etiology , Liver Neoplasms/pathology , Male , Middle Aged , Neoplasm Grading , Retrospective Studies , beta Catenin/metabolismABSTRACT
In 2012, a female wildlife biologist experienced fever, malaise, headache, generalized myalgia and arthralgia, neck stiffness, and a sore throat shortly after returning to the United States from a 6-week field expedition to South Sudan and Uganda. She was hospitalized, after which a maculopapular rash developed and became confluent. When the patient was discharged from the hospital on day 14, arthralgia and myalgia had improved, oropharynx ulcerations had healed, the rash had resolved without desquamation, and blood counts and hepatic enzyme levels were returning to reference levels. After several known suspect pathogens were ruled out as the cause of her illness, deep sequencing and metagenomics analysis revealed a novel paramyxovirus related to rubula-like viruses isolated from fruit bats.
