Department of Otolaryngology-Head and Neck Surgery, Keio University School of Medicine, Tokyo, Japan.
PLoS One. 2013 Aug 14;8(8):e71480. doi: 10.1371/journal.pone.0071480. eCollection 2013.
MicroRNA (miRNA) is an emerging subclass of small non-coding RNAs that regulates gene expression and has a pivotal role for many physiological processes including cancer development. Recent reports revealed the role of miRNAs as ideal biomarkers and therapeutic targets due to their tissue- or disease-specific nature. Head and neck cancer (HNC) is a major cause of cancer-related mortality and morbidity, and laryngeal cancer has the highest incidence in it. However, the molecular mechanisms involved in laryngeal cancer development remain to be known and highly sensitive biomarkers and novel promising therapy is necessary.
METHODOLOGY/PRINCIPAL FINDINGS: To explore laryngeal cancer-specific miRNAs, RNA from 5 laryngeal surgical specimens including cancer and non-cancer tissues were hybridized to microarray carrying 723 human miRNAs. The resultant differentially expressed miRNAs were further tested by using quantitative real time PCR (qRT-PCR) on 43 laryngeal tissue samples including cancers, noncancerous counterparts, benign diseases and precancerous dysplasias. Significant expressional differences between matched pairs were reproduced in miR-133b, miR-455-5p, and miR-196a, among which miR-196a being the most promising cancer biomarker as validated by qRT-PCR analyses on additional 84 tissue samples. Deep sequencing analysis revealed both quantitative and qualitative deviation of miR-196a isomiR expression in laryngeal cancer. In situ hybridization confirmed laryngeal cancer-specific expression of miR-196a in both cancer and cancer stroma cells. Finally, inhibition of miR-196a counteracted cancer cell proliferation in both laryngeal cancer-derived cells and mouse xenograft model.
CONCLUSIONS/SIGNIFICANCE: Our study provided the possibilities that miR-196a might be very useful in diagnosing and treating laryngeal cancer.
微小 RNA（miRNA）是一类新兴的小非编码 RNA，在包括癌症发展在内的许多生理过程中调节基因表达，具有关键作用。最近的报告显示，由于 miRNA 的组织或疾病特异性，它们可以作为理想的生物标志物和治疗靶点。头颈部癌症（HNC）是癌症相关死亡率和发病率的主要原因，其中喉癌的发病率最高。然而，喉癌发生发展中涉及的分子机制尚不清楚，因此需要高度敏感的生物标志物和新的有前途的治疗方法。
方法/主要发现：为了探索喉癌特异性 miRNA，我们将 5 例喉外科标本（包括癌症和非癌症组织）的 RNA 与载有人 723 个人类 miRNA 的微阵列杂交。在 43 例包括癌症、非癌性对应物、良性疾病和癌前发育不良的喉组织样本中，使用定量实时 PCR（qRT-PCR）进一步测试差异表达的 miRNA。在 miR-133b、miR-455-5p 和 miR-196a 中，配对样本之间的表达差异得到了重现，其中 miR-196a 作为最有前途的癌症生物标志物，在另外 84 个组织样本的 qRT-PCR 分析中得到了验证。深度测序分析显示，miR-196a 异质体的表达在喉癌中存在定量和定性偏差。原位杂交证实 miR-196a 在癌症和癌症基质细胞中均有喉癌特异性表达。最后，抑制 miR-196a 可逆转喉癌细胞系和小鼠异种移植模型中的癌细胞增殖。
结论/意义：我们的研究表明，miR-196a 可能在诊断和治疗喉癌方面非常有用。
