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Bcl-2 oncogene blocks differentiation and extends viability but does not immortalize normal human keratinocytes
A Nataraj1, S Pathak, V Hopwood
1UNIV TEXAS,MD ANDERSON CANC CTR,DEPT IMMUNOL,BOX 178,1515 HOLCOMBE BLVD,HOUSTON,TX 77030. UNIV TEXAS,MD ANDERSON CANC CTR,DEPT CELL BIOL,HOUSTON,TX 77030. UNIV TEXAS,MD ANDERSON CANC CTR,DEPT MOLEC PATHOL,HOUSTON,TX 77030.
International Journal of Oncology
|May 14, 2011
Summary
The bcl-2 oncogene prevents human keratinocyte differentiation and extends cell lifespan, suggesting its role in skin cancer development. It may be necessary, but not sufficient, for keratinocyte immortalization.
Area of Science:
- Oncology
- Cell Biology
- Dermatology
Background:
- Skin carcinogenesis involves uncontrolled cell growth and differentiation.
- The bcl-2 oncogene is known to inhibit apoptosis.
- Understanding keratinocyte differentiation is crucial for skin cancer research.
Purpose of the Study:
- To investigate the role of the bcl-2 oncogene in the early stages of skin cancer.
- To determine if bcl-2 prevents epidermal keratinocyte differentiation.
Main Methods:
- Primary human keratinocytes were transfected with the human bcl-2 gene.
- Transfected cells were assessed for differentiation under high calcium and serum conditions.
- Cell lifespan and chromosomal changes were monitored.
Main Results:
- The bcl-2 oncogene blocked keratinocyte differentiation.
- Human keratinocytes transfected with bcl-2 survived for over 24 weeks, compared to 5 weeks for controls.
- Late-stage bcl-2 transfected cells showed apoptotic bodies and telomere associations.
Conclusions:
- The bcl-2 oncogene appears to prevent keratinocyte differentiation.
- bcl-2 may be a key factor in keratinocyte immortalization during skin carcinogenesis.
- bcl-2 alone is not sufficient for the complete immortalization of human keratinocytes.
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