A growing body of evidence indicates that telomere dysfunction is a biological marker of progression in several types of cancer. However, the association between head and neck squamous cell carcinoma (HNSCC) and telomere length (TL) remains unknown. We measured the absolute TL levels in a well-characterised dataset of 211 tumoral vs normal tissues obtained from the same patients by quantitative polymerase chain reaction assay. Normalised TL levels were significantly lower in tumour samples than in normal tissue (P < 0.001) and there was a positive correlation between tumour tissue and normal mucosal tissue (R 2 = 0.176, P < 0.001). We were able to distinguish two classes, one with a tumour/normal TL ratio ≤ 0.3 (38.4%), which showed clear telomere erosion, and the other with a tumour/normal TL ratio > 0.3 (61.6%), in which the TL was slightly shorter or longer than that in normal tissue. Notably, the tumour/normal TL ratio was correlated with the likelihood of disease recurrence (P = 0.002), the 5-hydroxymethylcytosine level (P = 0.043), and expression of the ten-eleven translocation (TET) gene (P = 0.043). Our findings show that TL shortening and subsequent low levels of 5-hydroxymethylcytosine and TET expression may contribute to development of HNSCC.

Background: Infants admitted to the neonatal intensive care unit (NICU) have a higher incidence of congenital hearing loss compared with the healthy newborn population. Objectives: To clarify the relationship between risk factors for hearing impairment in NICU-treated infants and deterioration of the auditory brainstem response (ABR) threshold during childhood. Method: We screened 1,071 high-risk infants admitted to the NICU for hearing impairment. One-hundred forty-eight infants exhibited an abnormal ABR threshold of ≥40 dB nHL. We analyzed the correlation of change in ABR threshold with risk factors for future hearing impairment. Results: Among infants treated in the NICU, 148 (13.8%) exhibited an ABR threshold of ≥40 dB nHL; 107 of these 148 (72.3%) showed hearing change in the process (102 showed improvement to normal hearing level, whereas 5 showed further deterioration). Our analysis showed that the factors contributing to the elevation of ABR threshold were oxygen administration and chromosomal aberrations. Conclusions: Factors related to the elevation of ABR threshold were oxygen administration and the presence of chromosomal aberrations. Awareness of risk factors that are more likely to cause hearing loss in infants may aid in follow-up treatment of these children.

Background: Chronic inflammation is a risk factor for head and neck squamous cell carcinoma (HNSCC) and other diseases. Prostanoid receptors are clearly involved in the development of many types of cancer. However, their role is not simple and is poorly understood in HNSCC. Methods: Methylation profiles of prostanoid receptor family genes were generated for tumour samples obtained from 274 patients with HNSCC, including 69 hypopharynx, 51 larynx, 79 oral cavity, and 75 oropharynx tumour samples, by quantitative methylation-specific PCR. Promoter methylation was then evaluated with respect to various clinical characteristics and patient survival. Results: The mean number of methylated genes per sample was 2.05 ± 2.59 (range 0 to 9). Promoters of PTGDR1,

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