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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Aflatoxin B1, Carcinogens, Environmental, Carcinoma, Hepatocellular, Chi-Square Distribution, China, DNA Adducts, DNA Methylation, Environmental Exposure, Female, Gene Expression Regulation, Neoplastic, Gene-Environment Interaction, Genetic Predisposition to Disease, Humans, Immunohistochemistry, Kaplan-Meier Estimate, Liver Neoplasms, Male, Middle Aged, Multivariate Analysis, Polycyclic Aromatic Hydrocarbons, Prognosis, RNA, Messenger, Risk Assessment, Risk Factors, Time Factors, Tumor Suppressor Proteins.
user
Is rASSF1A hypermethylation associated with aflatoxin B1 and polycyclic aromatic hydrocarbon exposure in hepatocellular carcinoma? Context: RASSF1A hypermethylation is frequently observed in hepatocellular carcinomas (HCC). But the possible related risk factors and prognosis evaluation for this epigenetic alteration are still unknown. Methylation status, mRNA and protein expression of RASSF1A, aflatoxin B1 (AFB1) and polycyclic aromatic hydrocarbon (PAH)-DNA adducts, were examined in 103 cases of HCC. The expression of RASSF1A mRNA (20/103, r=-0.665) and protein (21/103, r=-0.761) were negatively related to RASSF1A hypermethylation (82/103). Multivariate analysis indicated that RASSF1A hypermethylation was related to AFB1- (p=0.046) and PAH-DNA adducts (p=0.040). Other factors including smoking, alcohol drinking, hepatitis B virus infection and clinicopathological parameters were not significantly associated with RASSF1A methylation. No difference in overall survival was observed between patients with and without RASSF1A hypermethylation (p=0.267).
assistant
AFB1- and PAH-DNA adducts may be associated with RASSF1A hypermethylation in hepatocarcinogenesis. RASSF1A methylation status may not be a proper predictor of overall survival for HCC. Final Decision: yes