Expression of CYLD, c-jun and Ki-67 in Middle Ear Cholesteatoma Epithelium and Its Significance

XIAO Zhiwen; JIANG Lixin

doi:10.3969/j.issn.1672-2922.2014.04.030

Abstract：Objective To study expression of the tumor suppressor gene CYLD (cylindromatosis), proto-oncogene c-jun and proliferating cell nuclear antigen Ki-67 in middle ear cholesteatoma epithelium, and their correlation, as well as their possible roles in the pathogenesis of middle ear cholesteatoma. Method Immunohistochemical techniques were used to detect expression of CYLD, c-jun and Ki-67 in middle ear cholesteatoma tissues from 30 patients (the experimental group) and in normal retroauricular skin from 20 of the patients (the control group). Results CYLD immunoreactivity was detected in the cytoplasm of epithelial cells. The reaction was mildly positive and mainly in the basal layer in middle ear cholesteatoma, while strong in all epithelial layers in the control group (normal retroauricular skin) (X2=14.901, p<0.05). The c-jun immuno?reactivity was detected in the cytoplasm and nuclei of epithelial cells, and positive or strong positive in all epithelial layers in middle ear cholesteatoma, but showing relative weak expression only in the basal layers in the control group (X2=16.333, p<0.05). Ki-67 immunoreactivity was detected in the nuclei of epithelial cells but not in cytoplasm. It showed strong positive ex? pression mainly in the basal and spinous layers (and sporadically in the granularlayer layer) in cholesteatoma epithelium, but relatively weak expression limited to the basal layer in the control groups (X2=13.675, p<0.05). In middle ear cholesteatoma epithelium, CYLD expression showed negative correlation to the expression of c-jun (rs=-0.401, p<0.05). Conclusion Middle ear cholesteatoma epithelium has a high proliferative capacity compared to epithelial cells of the normal skin. The abnormal ex?pression of CYLD and c-jun in middle ear cholesteatoma epithelium suggests their important roles in the formation and devel?opment of cholesteatoma. The negative correlation between CYLD and c-jun expression may exist in middle ear cholesteatoma.