Expressions of TRPVs in the cholesteatoma epithelium

Abstract

Objective: We have recently proposed a hypothesis that acid leakage through the cholesteatoma epithelium mediates bone resorption in middle ear cholesteatoma. In the present study, we investigated the expressions of transient receptor potential vanilloid (TRPV) channels, which have been shown to play roles in the regulation of epidermal barrier function, in the cholesteatoma epithelium in comparison with the normal skin.

Methods: Cholesteatoma epithelium and postauricular skin were collected from 17 patients with primary acquired middle ear cholesteatoma who underwent tympanomastoidectomy. Expressions of TRPV1, TRPV3, TRPV4, and TRPV6 were explored by fluorescence immunohistochemistry and quantitative reverse transcription-polymerase chain reaction (qRT-PCR).

Results: TRPV1, TRPV3, TRPV4, and TRPV6 mRNAs were all detected by qRT-PCR both in the skin and cholesteatoma tissue. Immunohistochemical staining showed that TRPV1 and TRPV3 were positive in the viable cell layers of the epidermis of the skin, and only TRPV3 was positive in those of the cholesteatoma epithelium. The immunoreactivity for TRPV3 was significantly weaker in cholesteatoma than in the skin.

Conclusions: The lower expression of TRPV3 in cholesteatoma may be one of the mechanisms underlying the increased permeability of this tissue. On the other hand, TRPV1, TRPV4, and TRPV6 are unlikely to be involved in the regulation of epithelial permeability in cholesteatoma.

Chinese abstract

目的: 我们最近提出了一个假说: 透过胆脂瘤上皮的酸渗漏可排解中耳胆脂瘤的骨吸收。在本研究中, 我们研究了与正常皮肤相比, 胆脂瘤上皮细胞中瞬时感官潜在香草素 (TRPV) 通道的表达, 已被证明在调节表皮屏障功能中发挥作用。

方法: 收集了17例患原发性中耳胆脂瘤并接受胆囊切除术的患者的胆脂瘤上皮和耳后皮肤。通过荧光免疫组织化学和定量逆转录聚合酶链反应 (qRT-PCR) 检测TRPV1、TRPV3、TRPV4和TRPV6的表达。

结果: TRPV1、TRPV3、TRPV4和TRPV6 mRNA均在皮肤和胆脂瘤组织中通过qRT-PCR得以测出。免疫组织化学染色显示, TRPV1和TRPV3在皮肤表皮的活细胞层中呈阳性, 在胆脂瘤上皮中只有TRPV3呈阳性。胆脂瘤中TRPV3的免疫反应性明显弱于皮肤中。

结论: TRPV3在胆脂瘤中的较低表达可能是该组织渗透性增加的原因之一。另一方面, TRPV1、TRPV4和TRPV6不太可能参与胆脂瘤上皮通透性的调节作用。

Keywords:

• Cholesteatoma
• transient receptor potential vanilloid
• epidermal barrier
• fluorescence immunohistochemistry
• quantitative reverse transcription-polymerase chain reaction

View correction statement:

Correction to: Ba Hung Do et al., Expressions of TRPVs in the cholesteatoma epithelium

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Additional information

Funding

This study was supported by a Grant-in-Aid for Scientific Research (C) (no. 16K11203; 2016-2018) from the Japan Society for the Promotion of Science. The authors have no other funding or financial relationships.