Ten Have-Opbroek A A, Benfield J R, Hammond W G, Dijkman J H
Department of Pneumology, Leiden University, The Netherlands.
Cancer Lett. 1996 Mar 29;101(2):211-7. doi: 10.1016/0304-3835(96)04137-7.
Alveolar type II cells are not present in normal epithelium of canine segmental bronchi but after carcinogen exposure they do occur in intra-epithelial lesions with all degrees of atypia and in invasive lesions with different glandular growth patterns. Immunohistochemistry for proliferation markers (PCNA; Ki-67) strongly suggest that such novel type II cells are pluripotential stem cells in canine bronchial carcinogenesis. Very likely, bronchial carcinogenesis is subject to an oncofetal mechanism of differentiation: bronchial epithelial retrodifferentiation followed by novel differentiation of alveolar tumor stem cells.
