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Abstract. Laryngeal squamous cell carcinoma (LSCC) is one of the most common head and neck malignancies with a poor prognosis. The aim of this study was to detect the expression of microRNAs (miRNAs) in supraglottic LSCC and attached normal mucosa using microarray assay, and explore the role of miRNAs in supraglottic LSCC. Fresh-frozen samples of five supraglottic LSCC and attached normal mucosa were obtained, and their various endogenous miRNAs were screened by microarray. miRNAs of interest were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR) in 48 supraglottic LSCC tumors and 10 normal mucosa tissues. In total, 38 miRNAs were differentially expressed in supraglottic LSCC, with 22 miRNAs being upregulated and 16 downregulated. Of the six miRNAs selected for qRT-PCR, miR-375, miR-139-3P, miR-1290 and miR-106b were differentially expressed in supraglottic LSCC with and without lymphatic metastasis.

Plasma miRNAs have been reported as biomarkers for various diseases. In this study, we investigated whether plasma concentrations of miR-126 may be useful as biomarkers for laryngeal squamous cell carcinoma (LSCC). We examined the function and mechanism of miR-126 in LSCC by using cell biology and molecular pathology techniques such as western blotting, quantitative PCR, IHC and IF. The expression of Camsap1 mRNA and protein is higher in cancer tissues compared to that in normal tissues. Both miR-126 and Camsap1 were related with the prognosis of LSCC patients. We found that miR-126 was able to inhibit LSCC partly by suppressing Camsap1 expression. In addition, Camsap1 expression induced microtubule formation and aggregation. This mechanism possibly explains why loss of miR-126 is frequently associated with tumor metastasis.

Cortical representation of time-varying features of acoustic signals is a fundamental issue of acoustic processing remaining unresolved. The rat is a widely used animal model for auditory cortical processing. Though some electrophysiological studies have investigated the neural responses to temporal repetitive sounds in the auditory cortex (AC) of rats, most of them were conducted under anesthetized condition. Recently, it has been shown that anesthesia could significantly alter the temporal patterns of neural response. For this reason, we systematically examined the single-unit neural responses to click-trains in the core region of rat AC under awake condition. Consistent with the reports on anesthetized rats, we confirmed the existence of characteristic tonotopic organizations, which were used to divide the AC into anterior auditory field (AAF), primary auditory cortex (A1) and posterior auditory field (PAF). We further found that the neuron's capability to synchronize to the temporal repetitive stimuli progressively decreased along the anterior-to-posterior direction of AC. The median of maximum synchronization rate was 64, 32 and 16 Hz in AAF, A1 and PAF, respectively. On the other hand, the percentage of neurons, which showed non-synchronized responses and could represent the stimulus repetition rate by the mean firing rate, increased from 7% in AAF and A1 to 20% in PAF. These results suggest that the temporal resolution of acoustic processing gradually increases from the anterior to posterior part of AC, and thus there may be a hierarchical stream along this direction of rat AC.

Abstract. Forkhead box Q1 (FOXQ1) is a forkhead transcription factor that is involved in numerous biological processes and has been shown to participate in tumorigenesis. However, the clinical significance of the expression of this protein in laryngeal carcinoma, and the mechanisms underlying its regulation in this disease remain unclear. The aim of present study was to measure the expression of FOXQ1 in laryngeal carcinoma, and to examine its effect on tumorigenesis. In the present study, reverse transcription-quantitative polymerase chain reaction and western blotting were employed to measure FOXQ1 expression in laryngeal carcinoma tissue samples, small interfering RNA specific to FOXQ1, was transfected into Hep2 cells and its effect on cell proliferation, cell cycle progression and cell migration was examined, using a CCK-8 assay, flow cytometry and a transwell migration assay, respectively. The results showed overexpression of FOXQ1 mRNA and protein in laryngeal cancer tissue samples. Inhibition of FOXQ1 suppressed cell growth and invasion, and arrested cells in the G0/G1 phase. Overexpression of FOXQ1 is associated with the development of laryngeal carcinoma and may enhance tumorigenesis through its effects on cell proliferation, cell cycle progression and cell migration.