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Published on: February 2, 2024
Abnormal DNA end-joining activity in human head and neck cancer
Ki-Hyuk Shin1, Mo K Kang, Reuben H Kim
1UCLA School of Dentistry, Los Angeles, CA 90095-1668, USA.
International Journal of Molecular Medicine
|April 6, 2006
Summary
Abnormal DNA end-joining (EJ) activities, particularly diminished precise repair, were found in immortalized and cancerous human oral cells. This aberrant DNA repair may contribute to genetic instability and cancer development.
Area of Science:
- Molecular Biology
- Genetics
- Cancer Research
Background:
- DNA double-strand breaks (DSBs) are critical DNA lesions repaired by DNA end-joining (EJ).
- Aberrant EJ activity can lead to mutations, aneuploidy, and genetic instability, a hallmark of cancer.
- Understanding the role of EJ in carcinogenesis is crucial for developing cancer therapies.
Purpose of the Study:
- To investigate the association between DNA EJ activities and carcinogenesis.
- To compare DNA EJ activities in normal, immortalized, and malignant human epithelial cells.
Main Methods:
- Assessed DNA end-joining activities in normal human oral keratinocytes (NHOK), immortalized HOK-16B cells, and head and neck squamous cell carcinoma (HNSCC) cells.
- Analyzed precise (error-free) and aberrant (microhomology-mediated and non-microhomology-mediated) end-joining activities.
Main Results:
- A significant decrease in precise DNA EJ activities was observed in HOK-16B and HNSCC cells compared to NHOK cells.
- Abnormal DNA EJ activities, including microhomology-mediated and non-microhomology-mediated end-joining, were exclusively detected in HOK-16B and HNSCC cells.
- These findings suggest a link between diminished precise DNA EJ and the presence of genetic instability in cancerous and pre-cancerous cells.
Conclusions:
- Aberrant DNA end-joining activity is prevalent in immortalized and malignant human oral cells.
- Diminished precise DNA EJ may contribute to genetic instability and oncogenic transformation.
- Targeting DNA EJ pathways could offer novel therapeutic strategies for head and neck squamous cell carcinoma.
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