Progressive stages of "transdifferentiation" from epidermal to mesenchymal phenotype induced by MyoD1 transfection, 5-aza-2'-deoxycytidine treatment, and selection for reduced cell attachment in the human keratinocyte line HaCaT.

摘要: The ability of the myogenic determination gene (MyoD1) to convert differentiating human keratinocytes (HaCaT cell-line) pathway and effect MyoD1 on epidermal phenotype was studied in culture surface transplants nude mice. transfection induced synthesis myosin, desmin, vimentin without substantially altering differentiation properties (morphology, keratin profile) vitro nor morphogenesis (formation a complex stratified squamous epithelium) transplants, demonstrating stability keratinocyte phenotype. 5-Aza-CdR treatment these MyoD1-transfected cells had little cultured but morphologically unstructured epithelium formed with no indications typical cell layers including cornification. Since prevention strata not accompanied by blocked markers (keratins K1 K10, involucrin, filaggrin), dissociation expression argues for independently controlled processes. A subpopulation less adhesive cells, isolated from 5-aza-CdR treated MyoD1-transfectants, lost most epithelial characteristics (epidermal keratins, desmosomal proteins, surface-glycoprotein Gp90) shifted mesenchymal/myogenic (fibroblastic morphology, transactivation Myf3 myogenin, vimentin, Gp130). Moreover, stratify remained as monolayer flat elongated transplants. These subsequent changes fully differentiated strongly argue "transdifferentiation" process which occurred original monoclonal HaCaT cells.