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Updated: May 5, 2026
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Deficient Pms2, ERCC1, Ku86, CcOI in Field Defects During Progression to Colon Cancer
Published on: July 29, 2010
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High frequency of K-ras mutations in human colorectal hyperplastic polyps
1Investigative Treatment Division, National Cancer Center Research Institute, Chiba, Japan.
Gut
|May 1, 1997
Summary
Common hyperplastic polyps may transform into cancerous colorectal neoplasms. Genetic analysis revealed K-ras mutations in nearly half of these polyps, suggesting they are neoplastic lesions.
Area of Science:
- Gastroenterology
- Molecular Biology
- Oncology
Background:
- Hyperplastic polyps are common benign colorectal growths.
- Traditionally considered low-risk, some evidence suggests they can become neoplastic.
Purpose of the Study:
- To investigate genetic alterations in colorectal hyperplastic polyps.
- To determine if hyperplastic polyps possess neoplastic potential.
Main Methods:
- Endoscopic resection of 28 colorectal polyps with serrated features.
- Analysis of K-ras gene mutations (codons 12 and 13) using PCR-RFLP.
- Immunohistochemical staining for intranuclear p53 protein.
Main Results:
- K-ras gene mutations were found in 47% of hyperplastic polyps and 56% of adenomas.
- p53 protein nuclear accumulation was observed in 22% of adenomas but not in hyperplastic polyps.
- Serrated polyps with K-ras mutations indicate neoplastic potential.
Conclusions:
- Certain hyperplastic polyps exhibit genetic alterations characteristic of neoplastic lesions.
- These findings suggest hyperplastic polyps can be precursors to colorectal cancer.
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