Reference SummaryWang QS, Carcinogenesis 1998 Nov;19(11):2001-6

Title

Altered expression of cyclin D1 and cyclin-dependent kinase 4 in azoxymethane-induced mouse colon tumorigenesis.

Authors

Wang QS; Papanikolaou A; Sabourin CL; Rosenberg DW

Journal

Carcinogenesis

Volume

19

Issue

11

Year

1998

Pages

2001-6

Abstract

Alterations in the expression of the cell cycle regulators, cyclin D1 and cyclin-dependent kinase 4 (Cdk4), have been implicated in malignancies of both humans and experimental animal models. We hypothesize that altered expression of cyclin D1 and Cdk4 may also be involved in mouse colon tumorigenesis induced by the chemical carcinogen, azoxymethane (AOM). In the present study, SWR/J mice were given AOM by i.p. injection at a dose of 10 mg/kg once a week for 8 weeks, and colonic tissue and tumors were isolated 18 weeks later. The expression and localization of cyclin D1 and Cdk4 were examined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemical analyses. Cyclin D1 and Cdk4 mRNA levels in tumor samples were increased 1.3-fold (P < 0.01) and 1.2-fold (P < 0.01), respectively, when compared with control mouse colon tissue. Control colon epithelium was uniformly negative for cyclin D1 immunoreactivity, whereas minimal Cdk4 nuclear staining was confined to the lower portion of the crypts within the control tissue. Both cyclin D1 and Cdk4 immunoreactive cells were markedly increased in preneoplastic lesions and in adenomas isolated from AOM-treated mice. Furthermore, some morphologically normal colon crypts from AOM-treated mice showed positive cyclin D1 immunoreactivity. These findings suggest that overexpression of cyclin D1 and Cdk4 occurs early in the AOM-induced mouse colon tumorigenesis and may contribute to tumor progression in this model.

Links

J:51245 – MGI References
9855016 – National Library of Medicine/PubMed

Strain Notes

Strain Note
SWR/J The wild type alleles of the Ccnd1 and Cdk4 genes were reported to be expressed in the colon of these mice

Models

Strain Model Name Treatment Agent(s) Organ Affected Frequency Model Details
SWR/J Intestine - Large Intestine - Colon adenoma
  • azoxymethane (AOM)
Intestine - Large Intestine - Colon

observed

SWR/J Intestine - Large Intestine - Colon dysplasia
  • azoxymethane (AOM)
Intestine - Large Intestine - Colon

observed

SWR/J Intestine - Large Intestine - Colon hyperplasia
  • azoxymethane (AOM)
Intestine - Large Intestine - Colon

observed