Expression of PPL in normal, atypical epithelium and cancer of the pharyngeal mucosa. (A) In normal hypopharyngeal mucosa, PPL is expressed in the upper layer of the squamous epithelium (arrows). (B) In atypical hypopharyngeal epithelium, PPL expression is rare (arrows). (C) In the pharyngeal cancer epithelium, PPL expression is slight and occurs on the ridge of the cornified epithelium. Note that in both the non-keratinized (asterisk) and keratinized cancer areas (arrows), PPL expression was scarce. Bar: 100 μm.
Tonoike et al. BMC Cell Biology 2011 12:41 doi:10.1186/1471-2121-12-41