[Biological change of normal human breast epithelial cells induced by B( a )P and NNK].

Objective: To explore the changes of biological characters of normal human epithelial cells treated chronicly with carcinogens.

Method: At picomolar concentrations of NNK and B [ a ] P carcinogens, noncancerous MCF10A cells were repeatedly treated. Properties of biological target endpoint were studied in cells after 20 cycle's treatment.

Results: It was found that the treatment can induce cell acquisition of properties of reduced dependence on growth factors, anchorage-independent growth,and acinar-conformational disruption.

Conclusion: MCF10A cells can acquire cancer-related properties after long-term,low-concentration treatment with carcinogens.