Hypermethylation of TIG1 in Head and Neck Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Decreased expression and growth suppression of Tazarotene-Induced Gene 1 (TIG1) were reported in prostate cancer. In this study, we examined the possibility of TIG1 transcriptional silencing by hypermethylation in head and neck cancer. SUBJECTS AND METHOD: We extracted DNA and total RNA from five head and neck cell lines (O11, O12, O19, O22 and O28), and three prostate cell lines (PC3, LNCap and DU145). We checked the methylation status of TIG1 by methylation-specific PCR (MSP) and RT-PCR. We also examined primary cancer tissues of 32 head and neck cancer, 31 prostate cancer and 10 normal samples. RESULTS: We found that all of five head and neck (100%) cell lines and two of three prostate (66.7%) cell lines were methylated. RT-PCR analysis confirmed the absence of TIG1 expression in six cell lines with methylation. We checked primary cancer by MSP and found TIG1 methylation in 16 of 32 (50%) head and neck cancers, and 17 of 31 (54.8%) prostate cancers. Normal head and neck and prostate tissues were free of methylation. CONCLUSION: Our results support the notion that methylation might be an important mechanism of TIG1 inactivation and a target event in head and neck cancer.

Functional Results of Voice and Swallowing in Patients Treated with Surgery or Radiation Therapy for Early Glottic Cancer / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: Laryngeal neoplasms such as early glottic cancer can be effectively treated with several methods, namely laser surgery, conservation laryngeal surgery and radiotherapy. Therefore, the preservation of the ability to speak and swallow normally is another important consideration in the selection of therapy for early glottic cancer. The purpose of this study is to compare the functional results of voice and deglutition for early glottic cancer patients treated with surgery or radiation. SUBJECTS AND METHOD: Between January 2002 and September 2004, 17 patients with the early glottic cancer who had undergone radiotherapy (n=6) or surgery (n=11) were retrospectively investigated. All the patients were phonetically analysed using CSL and Fo, Jitter, Shimmer and NHR were evaluated. For aerodynamic test, maximum phonation time (MPT) and mean air flow rate (MFR) were also evaluated. Modified barium swallow (MBS) was performed to evaluate swallowing function. RESULTS: There were no significant difference in all the vocal parameters between radiotherapy group and surgery group. But Shimmer differed significantly between radiotherapy group and laser cordectomy group. In aerodynamic study, MPT was significantly longer in the radiotherapy group than in the surgery group, but no significant difference was observed between the radiotherapy group and laser cordectomy group. MBS showed better results in the surgery group than in the radiotherapy group. CONCLUSION: Therapeutic modality for patients with early glottic cancer should be chosen in consideration of voice quality and swallowing, and according to multiple parameters of the patients' conditions.