Can Apoptosis Influence Initiation of Chemical Hepatocarcinogenesis?
Although the mechanism of action of cell proliferation in the carcinogenic process has not been clearly defined so far, it appears that cell proliferation is essential for the initiation phase, and it also characterizes the promotion phase, as well as the progression from hepatocyte nodules to cancer1–7. Undoubtedly, most of the studies aimed to determine the exact role of cell proliferation in the development of liver cancer have been focused on the initiation step. The evidence that stems out from these studies is that at least one round of cell proliferation is necessary for the accomplishment of the initiation process; replication of DNA containing carcinogen-induced miscoding lesions such as 06-alkylguanine8, 04-alkylthymine9, or non-coding lesions such as apurinic sites10, or certain types of gap filling mechanisms11, have been implicated as the key event.
KeywordsLead Nitrate Cyproterone Acetate Preneoplastic Lesion Proliferative Stimulus Ethylene Dibromide
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