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Emerging pathways in colorectal-cancer development.

Andrew M M Haydon·Jeremy R Jass
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Abstract

The past decade has seen the emergence of new pathways in the development of colorectal cancer. There is now clear evidence that subsets of these tumours do not show chromosomal instability and do not follow the suppressor pathway. Instead, about 15% of colorectal cancers are characterised by microsatellite instability (MSI). This feature arises through defective DNA mismatch repair, which is related either to a germline mutation (as in hereditary non-polyposis colorectal carcinoma) or to failure to express a mismatch-repair gene. CpG-island methylation has been linked to sporadic cancers with a high frequency of MSI. This type of methylation leads to loss of gene expression when it occurs in the promoter region of a gene. Tumours may have high or low type C (cancer-related) CpG-island methylation. When methylation affects hMLH1 (mismatch repair gene), the resultant cancer has high MSI.

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Biopsy, NeedleColorectal NeoplasmsDNA MethylationDNA, NeoplasmFemaleGene Expression RegulationGenetic Predisposition to DiseaseHumansMaleMicrosatellite RepeatsPrognosisPromoter Regions, GeneticSensitivity and SpecificityJournal ArticleReview

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Andrew M M Haydon, Jeremy R Jass. 2002. Emerging pathways in colorectal-cancer development.. https://doi.org/10.1016/s1470-2045(02)00649-6

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Targeting difficult accessible breast lesions: MRI-guided needle localization using a freehand technique in a 3.0 T closed bore magnet.

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Biopsy, Needle↗