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Updated: Jul 6, 2026
05:21
Real-time Imaging of Myeloid Cells Dynamics in ApcMin/+ Intestinal Tumors by Spinning Disk Confocal Microscopy
Published on: October 6, 2014
Loss of Rassf1a cooperates with Apc(Min) to accelerate intestinal tumourigenesis
L van der Weyden1, M J Arends, O M Dovey
1Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Cambridge, UK. lvdw@sanger.ac.uk
Oncogene
|April 9, 2008
Summary
Loss of Rassf1a accelerates intestinal tumor development in mice with Apc mutations. This study shows Rassf1a inactivation cooperates with Apc inactivation, increasing adenomas and decreasing survival.
Area of Science:
- Oncology
- Molecular Biology
- Genetics
Background:
- Promoter methylation of RAS-association domain family 1, isoform A (RASSF1A) is a common event in human tumors.
- Adenomatous polyposis coli (APC) gene inactivation is an early event in intestinal cancer genesis.
- RASSF1A loss occurs in premalignant bowel adenomas and is implicated in cell cycle, apoptosis, and beta-catenin signaling.
Purpose of the Study:
- To test if Rassf1a loss cooperates with Apc inactivation to accelerate intestinal tumorigenesis.
- To investigate the mechanistic link between Rassf1a, Apc, and beta-catenin signaling in intestinal cancer.
Main Methods:
- Interbreeding isoform-specific Rassf1a knockout mice with Apc(+/Min) mice.
- Comparative genomic hybridization (CGH) of adenomas.
- Immunohistochemical analysis for beta-catenin and Ki67.
Main Results:
- Loss of Rassf1a significantly increased small intestinal adenomas and accelerated tumor progression.
- Mice lacking Rassf1a showed earlier death from adenocarcinoma and decreased overall survival.
- Increased nuclear beta-catenin accumulation was observed in adenomas from Rassf1a(-/-); Apc(+/Min) mice, without changes in proliferation or chromosomal instability.
Conclusions:
- Rassf1a inactivation cooperates with Apc inactivation to promote intestinal tumorigenesis.
- The mechanism involves increased beta-catenin accumulation, likely due to disrupted Rassf1-beta-TrCP interaction.
- These findings highlight RASSF1A as a potential tumor suppressor in intestinal cancer.
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