Serum levels of microRNA-21 and microRNA-10a can predict long-term prognosis in laryngeal cancer patients: a multicenter study

Background: Laryngeal squamous cell carcinoma (LSCC) ranks as the second most common subtype of squamous cell sarcoma (SCC) of the head and neck. In clinical practice, more tools are required to assist doctors in identifying patients who are at risk of poor prognosis at an early stage. Many studies have shown that microRNA-21 plays an important role in LSCC. MicroRNA-10a has also been found to be differentially expressed in squamous cell carcinomas of the head and neck. This study aimed to test whether circulating microRNA-21 and microRNA-10a could serve as prognostic predictors for patients with LSCC. Methods: Between May 2009 and Jan 2015, laryngeal cancer patients who were treated at three medical centers were enrolled based on inclusion and exclusion criteria. Baseline blood samples were obtained before surgery, chemotherapy, or radiotherapy. MicroRNA array was used to detect the microRNAs that were differently expressed between the LSCC patients and healthy controls. The serum levels of selected microRNAs were tested in each patient using qRT-PCR. Clinical information was acquired from the patients' clinic or in-hospital records and all of the patients were followed-up. Results: A total of 236 patients (average age, 59.4 +/- 10.7 years; male, 223; 33.5% with supraglottic LSCC, and 66.5% with glottis LSCC) were enrolled into the final analysis. MicroRNA array showed that the serum level of microRNA-21 was higher and that of microRNA-10a was lower in the LSCC patients compared with the healthy controls. Patients at T I/II stage, N0 stage, M0 stage had lower serum level of microRNA-21 and higher serum level of microRNA-10a. Serum level of microRNA-21 and microRNA-10a both differed significantly between patients with LSCC of well, moderate and poor differentiation. Cox proportional hazards model revealed that T stage, N stage, M stage, age, and ratio of serum level of microRNA-21 and microRNA-10a were risk factors associated with 5-year survival rate in patients with LSCC. Kaplan Meier survival analysis revealed that lower baseline ratio of serum level of microRNA-21 and microRNA-10a predict better 5 years survival. The receiver-operating characteristic curve demonstrated the ratio had a good ability to discriminate patients survive at the end of five years follow-up, with an area under the curve (AUC) of 0.8965 (95% CI: 0.7849-0.9811). Conclusions: The serum levels of microRNA-21 and microRNA-10a are associated with long-term prognosis in laryngeal cancer patients. Lower serum level of microRNA-21 and higher serum level of microRNA-10a predict better prognosis in LSCC patients.