Laryngeal carcinoma represents a frequently diagnosed head and neck cancer. Despite of the various available treatments, the clinical outcomes of the patients has not been significantly improved during the past three decades [15]. Low early diagnosis rate may be responsible for the high mortality [4]. Surgery and radiotherapy are effective treatments for patients diagnosed at early stages, but the therapeutic effects are limited for those diagnosed with advanced stages, due to the high recurrence rate [16]. Therefore, identification of novel biomarkers for early diagnosis may be a promising approach to improve the outcomes of the patients.
As gene expression regulators, miRNAs play important roles in various biological processes, such as development, cell proliferation, apoptosis, differentiation, as well as carcinogenesis [17, 18]. Growing evidences have demonstrated that miRNAs as oncogenes or suppressors are involved in various human malignancies. Given their functional roles in tumor progression, miRNAs are considered as promising candidate biomarkers for cancer diagnosis, prognosis, and treatments. In laryngeal cancer, a variety of miRNAs biomarkers were identified. For examples, Wu er al. reported that laryngeal cancer tissues exhibited increased expression of miR-148a and miR-375 which might serve as diagnostic biomarkers for the cancer [19]. Zhang et al. reported that up-regulation of miR-23a in laryngeal cancer showed positive correlation with aggressive clinical parameters of the patients, moreover, its elevated expression predicted poor prognosis[20]. Based on the related studies, we speculated that the expression profile of miRNAs showed significant association with tumor development and progression, and they held the potential to serve as predictive biomarkers for human malignancies.
MiR-210, a common member of miRNA family, has been determined to play an important role in tumourgenesis. The increased expression of miR-210 was observed in various cancer, such as lung adenocarcinoma, renal cell carcinoma, colorectal cancer, suggesting its carcinogenic function in these cancers [21–23]. In this study, we found that the expression level of miR-210 was higher in laryngeal carcinoma patients than that in healthy group. Moreover, the increased expression of miR-210 was significantly correlated with advanced TNM stage and positive distant metastasis. All the data revealed that miR-210 as a tumor oncogene played a promoting role in malignant development and progression of laryngeal carcinoma. This conclusion was consistent with the previous results obtained in other types of cancer.
Given its oncogenic roles in tumorigenesis, miR-210 was identified as a biomarker for several cancers. In clear cell renal cell carcinoma, up-regulation of miR-210 showed significant association with tumor recurrence and poor prognosis of the patients, suggesting its capacity as a prognostic indicator for the disease [24]. Wang et al. reported that serum level of miR-210 was significantly higher in colorectal cancer patients than that in the healthy individuals, moreover, its elevated expression was positively correlated with malignant tumor progression and poor prognosis. Circulating miR-210 might be a potential biomarker for early detection and prognosis evaluation of the disease [25]. In this study, we estimated the diagnostic performance of serum miR-210 in laryngeal cancer. The results suggested that miR-210 could distinguish the laryngeal cancer patients from the healthy individuals with high sensitivity and specificity. MiR-210 might be a potential diagnostic biomarker for laryngeal carcinoma patients. However, the sample size was relatively small, and the application value of serum miR-210 for laryngeal carcinoma required further identification. In addition, the carcinogenic mechanisms of miR-210 in laryngeal cancer were poorly known. Further analysis were still needed to address the related issues.