I just picked at U of Pennsylvania’s web site for dermatology and grabbed this bit of info under Cotsarelis bio. Maybe it was discussed and posted before… but this is the first time I heard anything about the possibility of tumors forming. Thoughts.
Basic Science Research Summary
- Epithelial Stem Cells: A major goal of my laboratory is to identify genes controlling epithelial stem cells. We originally localized cutaneous epithelial stem cells to an area of the hair follicle called the bulge in both mouse and human skin. Using expression cloning, we identified keratin 15 (K15) as a marker for bulge cells. K15 is an intermediate filament protein that is preferentially expressed at high levels in bulge cells. We then isolated the K15 promoter. Keratin promoters are powerful tools for studying skin biology that have lead to an improved understanding of the genetic regulation of hair growth and development, as well as cutaneous carcinogenesis. The K15 promoter targets epithelial stem cells and will be valuable for studying the role of bulge cells in alopecia and carcinogenesis.
We are currently targeting several different genes to the bulge cells of transgenic mice using the K15 promoter to address the role of different oncogenes in tumorigenesis and alopecia. Using Real Time PCR, microarray analysis, laser capture microdissection, and a host of other conventional molecular techniques, we are studying the role of novel and known genes in hair follicle cycling and cutaneous biology.
Cutaneous Gene Therapy: We have developed a means for introducing plasmid DNA into human hair follicle progenitor cells by applying a mixture of DNA and liposomes topically to human skin transplanted to immunodeficient (scid) mice. The long-term goals of this project are to treat disorders of the skin and hair using this approach.
Carcinogenesis: Since epithelial stem cells rarely proliferate and are present throughout the lifetime of the individual, they may be susceptible to accumulating DNA damage, which can result in tumor formation. We are currently studying the role of epithelial stem cells in tumors of the skin as well as other epithelial tissues, such as in the eye and gastrointestinal tract.