Department of Otolaryngology and Communication Sciences, Medical College of Wisconsin, Milwaukee, Wisconsin 53226, USA.
Otol Neurotol. 2009 Oct;30(7):998-1005. doi: 10.1097/MAO.0b013e3181b4e91f.
The goal of this study was to identify novel regulatory mechanisms controlling the growth and proliferation of cholesteatoma. Specifically, the potential role of microRNAs, regulators of protein translation, was studied in cholesteatoma.
This study represents a molecular biologic investigation characterizing and comparing microRNA and protein expression in cholesteatoma and normal postauricular skin.
Cholesteatoma and normal skin were taken from patients at the time of surgery. Tissue was processed for RNA and protein extraction. Real-time reverse-transcriptase-polymerase chain reaction was used to assess levels of human microRNAs, reverse-transcriptase-polymerase chain reaction was used to confirm the presence of upstream regulators, and Western blot analyses were used to assess levels of downstream target proteins.
Among the microRNAs investigated, human microRNA-21 (hsa-miR-21) showed a 4.4-fold higher expression in cholesteatoma as compared with normal skin (p = 0.0011). The downstream targets of hsa-miR-21, PTEN and programmed cell death 4, were found to be greatly reduced in 3 of 4 cholesteatoma samples. Proposed upstream regulators of hsa-miR-21 expression (CD14, interleukin 6R, gp130, and signal transducer and activator of transcription 3) were present in all cholesteatoma tissues.
MicroRNAs represent powerful regulators of protein translation, and their dysregulation has been implicated in many neoplastic diseases. This study specifically identified up-regulation of hsa-miR-21 concurrent with down-regulation of potent tumor suppressor proteins PTEN and programmed cell death 4. These proteins control aspects of apoptosis, proliferation, invasion, and migration. The results of this study were used to develop a model for cholesteatoma proliferation through microRNA dysregulation. This model can serve as a template for further study into potential RNA-based therapies for the treatment of cholesteatoma.
本研究旨在确定控制胆脂瘤生长和增殖的新调控机制。具体而言，研究了调控蛋白翻译的 microRNA 在胆脂瘤中的潜在作用。
本研究是一项分子生物学研究，对胆脂瘤和正常耳后皮肤中的 microRNA 和蛋白质表达进行了特征描述和比较。
在手术时从患者中获取胆脂瘤和正常皮肤组织。对组织进行 RNA 和蛋白质提取处理。采用实时逆转录聚合酶链反应评估人 microRNA 的水平，采用逆转录聚合酶链反应确认上游调节剂的存在，采用 Western blot 分析评估下游靶蛋白的水平。
在所研究的 microRNA 中，hsa-miR-21 在胆脂瘤中的表达水平比正常皮肤高 4.4 倍（p=0.0011）。hsa-miR-21 的下游靶标 PTEN 和程序性细胞死亡 4 在 4 个胆脂瘤样本中的 3 个中发现大量减少。hsa-miR-21 表达的拟议上游调节剂（CD14、白细胞介素 6R、gp130 和信号转导和转录激活因子 3）均存在于所有胆脂瘤组织中。
microRNA 是蛋白质翻译的强大调控因子，其失调与许多肿瘤性疾病有关。本研究特别鉴定出 hsa-miR-21 的上调与强效肿瘤抑制蛋白 PTEN 和程序性细胞死亡 4 的下调同时发生。这些蛋白质控制凋亡、增殖、侵袭和迁移的各个方面。本研究的结果被用于通过 microRNA 失调开发胆脂瘤增殖模型。该模型可以作为进一步研究潜在 RNA 治疗胆脂瘤的模板。
