Reference SummarySteffensen IL, Cancer Res 2001 Dec 15;61(24):8689-96

Title

Intestinal tumorigenesis in multiple intestinal neoplasia mice induced by the food mutagen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine: perinatal susceptibility, regional variation, and correlation with DNA adducts.

Authors

Steffensen IL; Schut HA; Paulsen JE; Andreassen A; Alexander J

Journal

Cancer Res

Volume

61

Issue

24

Year

2001

Pages

8689-96

Abstract

In our previous experiments, multiple injections with the food mutagen 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP) were used to induce intestinal tumors in C57BL/6J-multiple intestinal neoplasia (Min)/+ mice. To define the period of highest susceptibility to PhIP perinatally, we first determined the effect of a single s.c. injection. Ten or 50 mg/kg PhIP increased the number and diameter of small intestinal tumors dose-dependently in 3-day-old Min/+ mice. In the colon, only 50 mg/kg PhIP increased the incidence and number of tumors. The number of dysplastic aberrant crypt foci decreased from weeks 7 to 11. In the same period, an increase in the number of tumors was seen, indicating that over time the dysplastic aberrant crypt foci develop into tumors. Min/+ mice were then exposed in utero through their dams being given one s.c. injection of 50 mg/kg PhIP 3 days before giving birth or were exposed directly to the same dose on day 3, 12, or 36 after birth. Remarkably, the most susceptible period for tumorigenesis in the small intestine was between days 3-12 after birth, whereas in the colon it was from day 3 before to day 3 after birth. Furthermore, we examined whether the formation of DNA adducts determined after 24 h could explain the observed time-dependent and regional susceptibility to PhIP. A higher level of PhIP-DNA adducts was found after exposure on day 12 after birth, compared with day 36 after birth, in all parts of the small intestine but not in the colon, which was in close accordance with the numbers of tumors present. The levels of PhIP-DNA adducts along the intestines were highest in the middle and distal parts of the small intestine, where tumor numbers were also the highest. In conclusion, Min/+ mice are most susceptible to intestinal tumor induction by PhIP from day 3 before to day 12 after birth, and this susceptibility could at least partly be explained by the formation of PhIP-DNA adducts.

Links

J:73361 – MGI References
11751386 – National Library of Medicine/PubMed

Strain Notes

Strain Note
C57BL/6J-ApcMin/+ Mice were generated by mating C57BL/6J females with C57BL/6J-ApcMin/+J males originally purchased from The Jackson Laboratory.

Models

Strain Model Name Treatment Agent(s) Organ Affected Frequency Model Details
C57BL/6J-ApcMin/+ Intestine - Large Intestine - Colon foci - aberrant crypt (ACF)
  • 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)
Intestine - Large Intestine - Colon

observed - 93

C57BL/6J-ApcMin/+ Intestine - Large Intestine - Colon foci - aberrant crypt (ACF) Intestine - Large Intestine - Colon

86 - 90

C57BL/6J-ApcMin/+ Intestine - Large Intestine - Colon tumor
  • 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)
Intestine - Large Intestine - Colon

observed - 88

C57BL/6J-ApcMin/+ Intestine - Large Intestine - Colon tumor Intestine - Large Intestine - Colon

30 - 45

C57BL/6J-ApcMin/+ Intestine - Small Intestine - Distal tumor
  • 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)
Intestine - Small Intestine - Distal

observed

C57BL/6J-ApcMin/+ Intestine - Small Intestine - Medial tumor
  • 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)
Intestine - Small Intestine - Medial

observed

C57BL/6J-ApcMin/+ Intestine - Small Intestine - Proximal tumor
  • 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)
Intestine - Small Intestine - Proximal

observed

C57BL/6J-ApcMin/+ Intestine - Small Intestine tumor
  • 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP)
Intestine - Small Intestine

observed - 100

C57BL/6J-ApcMin/+ Intestine - Small Intestine tumor Intestine - Small Intestine

100