FIG. 1.

Exposure to low concentrations of arsenic combined with ethanol exhibits low toxicity in colon cancer cells but high toxicity in normal colon cells. (A–C) DLD-1, HCT116, and CRL-1807 cells were exposed to arsenic (As), 0.4% ethanol (EtOH), or arsenic combined with ethanol at indicated concentrations for 24h, after which an MTT assay was performed. (D) Colony formation assays were carried out with DLD-1 cells exposed to arsenic and/or ethanol for 6 days at the indicated concentrations. The quantitative results were shown by manual counting of colonies.

Columns, mean of three or six duplicates; bars, SE (*p ≤ 0.05).