The 15 day-cultured cBAL111 cells and, for comparison, hepatoblastoma derived HepG2 cells were characterized for three progenitor cell markers by flow cytometry, i.e. CD146, a marker for various cells including mesenchymal progenitor cells and hepatocytes during liver regeneration [25,26], CD326 (EpCAM), an epithelial marker upregulated in gastrointestinal carcinomas [27] and CD133, a marker for progenitor cells of various origins, like endothelial cells, haematopoietic cells and neural cells [28]. The gene discussed is PROM1; the disease is hepatoblastoma.