Cholesteatoma in Transition

Introduction:

Cholesteatoma is a destructing process of the middle ear due to non-self-limiting chronic proliferative inflammation. Possible consequences include destruction of bony structures with hearing loss, vestibular dysfunction, facial nerve paralysis and intracranial complications. The therapy of choice is surgical. So far, little is known for the etiopathogenesis of cholesteatoma. New studies focus on the innate immune system and the microbiome.

Methods:

Samples of cholesteatoma and healthy ear canal skin were taken during ear operations. Affymetrix Microarray experiments were conducted by 332 cholesteatom genes, and further expression of target-related genes was confirmed using qPCR. Using TUNEL staining, immunohistochemistry on cryosections and in Situ apoptosis detection kit, apoptosis was determined and quantified. The microbiome was determined from tissue biopsies.

Results:

Cholesteatoma shows an upregulation of different gene networks, including signalling pathways of the innate immune system, the NFkB pathway, B/T-cell activation, apoptosis and NOD pathway. Compared to healthy ear canal skin (EAS), in cholesteatoma NOD2 and TNFα mRNA and protein expression are significantly upregulated. Whereas apoptosis genes are dysregulated and genes of DNA repair are significantly down-regulated. Microbiome analysis show a heterogeneous colonization of different microorganisms. The families of the Pseudomonadaceae, Corynebacteriaceae and Micrococcaceae were particularly prominent.

Conclusions:

These results demonstrate that the etiopathogenesis of cholesteatoma is in transition and that the immune system and microbiome are in the focus of new research and therapeutic approaches.

PD. Dr. Anke Leichtle

Universitätsklinikum Schleswig-Holstein -Campus Lü,

Ratzeburger Allee 160, 23538

Lübeck

Email: [e-mail]

Publication History

Publication Date:
23 April 2019 (online)