{'fraction_non_alphanumeric': 0.03597560975609756, 'fraction_numerical': 0.036585365853658534, 'mean_word_length': 5.0777777777777775, 'pattern_counts': {'":': 0, '<': 1, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Expression Patterns of Ki-67 and Telomerase Activity in Middle Ear Cholesteatoma

Background: Keratinocytes in cholesteatoma demonstrate uncoordinated hyperproliferation, migration, and invasion properties. There is a controversy regarding the impact of Ki-67 and telomerase activities on cellular proliferation in cholesteatoma. We studied expression of Ki-67 protein and telomerase activity in cholesteatoma and its relationship with clinical findings. Methods: The expression level of Ki-67 protein was examined by immunohistochemical analysis of 51 cholesteatomas and 6 skin tissues obtained from patients during ear surgery. Telomerase activity was determined in 23 samples of cholesteatomas and 6 skin samples by polymerase chain reaction-based telomeric-repeat amplification protocol assay. Results: The presence of Ki-67 protein was observed in 21 (41.2%) of 51 samples of acquired cholesteatoma. The average Ki-67 labeling index in the cholesteatoma group was 28.9 ± 9.2 and was higher than that in the skin group (18.2 ± 6.1). Telomerase activity was detected in 2 (8.7%) of 23 samples of cholesteatoma (21 of them were Ki-67 staining positive and 2, negative) and in 3 (50%) of 6 of control skin samples (p < 0.05). Conclusion: This study showed increased expression of Ki-67 in cholesteatoma, whereas there was no significant difference in rate of Ki-67 positive staining between skin and cholesteatoma (p = 0.066). Telomerase activation is a rare event in cholesteatoma. We assume that the absence of telomerase may lead to generation dysfunctional telomeres what in turn may impair the proliferative capacity of cholesteatoma.