Table 2

Time dependence of tumor promotion by 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)


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).

Messner and Kowdley BMC Gastroenterology 2008 8:2   doi:10.1186/1471-230X-8-2

Open Data