The Hyperproliferation Mechanism of Cholesteatoma Based on Proteomics: SNCA Promotes Autophagy-Mediated Cell Proliferation Through the PI3K/AKT/CyclinD1 Signaling Pathway.

Cholesteatoma is a chronic inflammatory ear disease with abnormal keratinized epithelium proliferation and tissue damage. However, the mechanism of keratinized epithelium hyperproliferation in cholesteatoma remains unknown. Hence, our study sought to shed light on mechanisms affecting the pathology and development of cholesteatoma, which could help develop adjunctive treatments. To investigate molecular changes in cholesteatoma pathogenesis, we analyzed clinical cholesteatoma specimens and paired ear canal skin with mass spectrometry-based proteomics and bioinformatics. From our screen, alpha-synuclein (SNCA) was overexpressed in middle ear cholesteatoma and might be a key hub protein associated with inflammation, proliferation, and autophagy in cholesteatoma. SNCA was more sensitive to lipopolysaccharide-induced inflammation, and autophagy marker increase was accompanied by autophagy activation in middle ear cholesteatoma tissues. Overexpression of SNCA activated autophagy and promoted cell proliferation and migration, especially under lipopolysaccharide inflammatory stimulation. Moreover, inhibiting autophagy impaired SNCA-mediated keratinocyte proliferation and corresponded with inhibition of the PI3K/AKT/CyclinD1 pathways. Also, 740Y-P, a PI3K activator reversed the suppression of autophagy and PI3K signaling by siATG5 in SNCA-overexpressing cells, which restored proliferative activity. Besides, knockdown of SNCA in RHEK-1 and HaCaT cells or knockdown of PI3K in RHEK-1 and HaCaT cells overexpressing SNCA both resulted in attenuated cell proliferation. Our studies indicated that SNCA overexpression in cholesteatoma might maintain the proliferative ability of cholesteatoma keratinocytes by promoting autophagy under inflammatory conditions. This suggests that dual inhibition of SNCA and autophagy may be a promising new target for treating cholesteatoma.

Clinical efficacy of the 'sandwich technique' in repairing cholesteatoma with labyrinthine fistula.

BACKGROUND: Labyrinthine fistula is the most common complication of middle ear cholesteatoma. AIMS/OBJECTIVES: To explore the postoperative hearing changes and surgical results of repairing middle ear cholesteatoma with labyrinthine fistula using the 'sandwich technique'. MATERIALS AND METHODS: We retrospectively studied the clinical data of 36 patients (36 ears) who underwent surgical treatment for cholesteatoma with labyrinthine fistula. All patients were treated by completely removing the cholesteatoma matrix and repairing the fistula using the 'sandwich technique'. The hearing, clinical features, radiological data, intraoperative findings, and surgical results were respectively analyzed. RESULTS: Most labyrinthine fistulas were located in the lateral semicircular canal (94%). Fifty percent of fistulas were of medium size. Based on Dornhoffer classification, 17 cases of labyrinthine fistulas were classified as I. In 34 patients, the average bone conduction threshold improved or did not change after surgery. Two patients had preoperative facial paralysis. During follow-up (3-60 months), all patients had no postoperative vertigo symptoms and disease recurrence. CONCLUSIONS: Following the removal of the cholesteatoma matrix, the fistula is repaired using the "sandwich technique", which preserves or increases hearing and achieves an anti-vertiginous effect. SIGNIFICANCE: This finding suggests that, 'sandwich technique' is a feasible procedure to treat cholesteatoma with labyrinthine fistula.

A retrospective study of 20 patients with Kimura's disease from China.

BACKGROUND: Kimura's disease (KD) is an eosinophilic proliferative lymphoid disease with rare incidence rate and nonspecific clinical symptoms. OBJECTIVES: To investigate the clinical characteristics, diagnosis, treatment, and prognosis of KD. MATERIALS AND METHODS: The clinical manifestations, laboratory examination, imaging examination, proposed treatment, and prognosis of 20 patients with KD treated in our hospital were retrospectively analyzed. RESULTS: All cases showed painless masses. The proportion of peripheral blood eosinophils rose in 18 cases (90%), the eosinophil count increased in 14 cases (70%) and the serum immunoglobulin E (IgE) levels were significantly increased in 5 patients (100%). Pathological examination revealed follicular hyperplasia, eosinophils infiltration, and tiny vessels proliferation in KD samples. CONCLUSIONS: KD should be considered when the patients suffered head and neck subcutaneous painless mass, increased peripheral blood eosinophils and raised serum IgE level. Pathological examination is the golden standard for diagnosing KD. Surgical intervention, medical treatments, and radiotherapy may be effective for KD treatment. SIGNIFICANCE: This study might shed a light on improving the diagnosis and treatment for KD.