Co-expression of p16INK4A and Laminin 5 by Keratinocytes: A Wound-Healing Response Coupling Hypermotility with Growth Arrest that Goes Awry During Epithelial Neoplastic Progression

The replicative lifespan of human keratinocytes in culture is restricted by a telomere-unrelated induction of p16INK4A (p16) and p14ARF. We have found that, in vivo, p16 is expressed by epidermal and oral keratinocytes at the migrating fronts of healing wounds and at the stromal interface of severely dysplastic and early invasive lesions and that such cells also invariably display increased expression of Laminin 5 (Lam5). In culture, p16 and...