BACKGROUND: Fanconi Anemia (FA) is an autosomal recessive inherited disease, which is characterized by developmental abnormalities, progressive bone marrow failure and a predisposition to cancer. The phenotypes of FA cells show extreme sensitivities towards oxygen and DNA cross linking agents, such as diepoxybutane and mitomycin C (MMC). METHODS: In the current study, retroviruses expressing the FANCA gene were prepared to create the stable cell lines, Hela (cervical carcinoma) and MCF10A (breast). The expression of FANCA protein in the Hela and MCF10A stable cells, following puromycin selection, was checked using Western blot. The difference in the cell growth between the parent and FANCA expressing cells following MMC treatment was checked using the MTT assay. RESULTS: The expression of exogenous FANCA protein in the Hela and MCF10A stable cells was observed using Western blot. The MCF10A cells expressing exogenous FANCA were resistant to MMC concentrations with the range 0.01~1 micrometer compared with the MCF10 parent cells. However, at an MMC concentration of 10 micrometer, there was no difference in the susceptibility between the parent and FANCA expressing MCF10 cells. The Hela cells expressing FANCA showed no resistance at any MMC concentration (0.01~10 micrometer). CONCLUSION: FANCA protein is an important factor for resistance to the cross linking agent, MMC, in MCF10A breast cells, but not in Hela cervical carcinoma cells.