Mutant KRAS in aberrant crypt foci (ACF): initiation of colorectal cancer?

Biochim Biophys Acta. 2005 Nov 25;1756(2):83-96. doi: 10.1016/j.bbcan.2005.06.002. Epub 2005 Jul 18.


Since aberrant crypt foci (ACF) were first described in 1987, they have been the subjects of hundreds of papers; however, the debate continues about their role in colorectal tumorigenesis. This review focuses on the many phenotypic, genetic and epigenetic alterations in ACF that support the hypothesis that ACF are putative precursors of colorectal cancer in both humans and experimental animals. Human ACF, both with and without dysplasia, are monoclonal and display evidence of chromosomal instability. Both of these characteristics are shared by colorectal cancers. While most ACF do not have APC mutations, a large proportion has KRAS mutations and methylated SFRP1 and SFRP2 genes. This epigenetic inactivation gives rise to constitutive Wnt signaling in these putative precursors of colorectal cancer.

Publication types

  • Research Support, N.I.H., Extramural
  • Review

MeSH terms

  • Adenomatous Polyposis Coli / genetics*
  • Animals
  • Colorectal Neoplasms / genetics*
  • DNA Methylation
  • Disease Models, Animal
  • Genes*
  • Genes, ras*
  • Humans
  • Mutation*