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Table 2 Time dependence of tumor promotion by iron.

From: Neoplastic transformation of rat liver epithelial cells is enhanced by non-transferrin-bound iron

MNNG Promoter Number of soft agar colonies per 25,000 cells1
   Week 12 Week 14 Week 16 Week 18 Week 20
0 50 μM FAC 0.8 (+/- 0.5) 0.8 (+/- 0.5) 3.5 (+/- 1.2) 2.3 (+/- 0.5) 4.0 (+/- 2.0)
0.5 50 μM FAC 7.5 (+/- 1.4) 4.5*(+/- 0.5) 7.0*(+/- 0.4) 17.8*(+/- 1.3) 52.7*(+/- 1.2)
0 200 μM FAC 5.3 (+/- 1.2) 1.0 (+/- 0.4) 10.8 (+/- 2.4) 9.3 (+/- 1.0) 2.3 (+/- 1.2)
0.5 200 μM FAC 12.8*(+/- 1.0) 21.5*(+/- 0.3) 32.5 (+/- 8.5) 66.0*(+/- 9.0) >99* (n.d.)
0 200 μM AmCit 1.5 (+/- 0.3) 0.0 (+/- 0.0) 1.3 (+/- 0.6) 0.0 (+/- 0.0) 0.3 (+/- 0.3)
0.5 200 μM AmCit 1.3 (+/- 0.5) 0.0 (+/- 0.0) 0.5 (+/- 0.3) 0.0 (+/- 0.0) 0.7 (+/- 0.7)
  1. 1Cells exposed or not to 0.5 μg/ml MNNG were cultured with FAC (or Ammonium Citrate control) for the indicated times, with 2 week passaging intervals, prior to soft agar assay (means of n = 4 soft agar dishes; *p < 0.01 compared to 200 μM AmCit only controls). The agar dishes from cells treated with 0.5 μg/ml MNNG + 20 weeks 200 μM FAC had too many colonies to accurately count (the s.e.m. was not determined).