Charimen’s Overview on Carcinogen-Induced Modification in DNA
Carcinogen-induced modifications in DNA deserve consideration as endpoints in carcinogenicity testing because of the evidence implicating genetic determinants in carcinogenesis; e.g., inherited differences in susceptibility to cancer (6), the common and sometimes specific occurrence of chromosomal abnormalities in cancer cells (8), the frequent correlation in chemicals between genotoxicity and carcinogenicity (7), and the transforming activity of oncogenic nucleotide sequences (2). At the same time, however, the kinetics of carcinogenesis in vivo and of cell transformation in vitro imply that neoplastic transformation usually involves sequential genetic changes, which may vary with the carcinogenic stimulus in question, the stage in the cancer process affected, the target cells at risk, and the capability of affected cells to repair or modify carcinogen-induced alterations in DNA (3,5,10).
KeywordsTumor Promoter Aberrant Methylation Transforming Activity Strand Breakage Affected Cell
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