title: Bcl-2 oncogene blocks differentiation and extends viability but does not immortalize normal human keratinocytes.
abstract: To ascertain whether the bcl-2 oncogene plays a role in the initial stages of skin carcinogenesis by preventing differentiation of epidermal keratinocytes, we transfected primary human keratinocytes with the human bcl-2 gene and then determined whether these transfectants escape high calcium- and serum-induced differentiation. We found that the bcl-2 oncogene blocked differentiation and extended the life span of human keratinocytes in culture by over 24 weeks compared with cells transfected with pZip-neo DNA, which only grew for 5 weeks in culture. Keratinocytes transfected with the bcl-2 oncogene exhibited apoptotic bodies and telomere-telomere association between chromosomes toward the end of their life-span. These results suggest that die bcl-2 oncogene may be necessary but not sufficient for the immortalization of human keratinocytes.
authors.affiliation: UNIV 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.
authors.forename: A
authors.initials: A
authors.lastname: Nataraj
authors.forename: S
authors.initials: S
authors.lastname: Pathak
authors.forename: V
authors.initials: V
authors.lastname: Hopwood
authors.forename: T
authors.initials: T
authors.lastname: McDonnell
authors.forename: H
authors.initials: H
authors.lastname: Ananthaswamy