Promoter hypermethylation and mRNA expression of TSLC1 gene in laryngeal squamous cell carcinoma

    WANG Junª²Li, ZHANG Huiª²Zhong, BAI Wanª²Sheng, LIU Li, BIAN Ka, CHENG Shiª²Yin

    1Department of Otorhinolaryngology

    2Department of Clinical Laboratory, Tangdu Hospital, Fourth Military Medical University, Xi¬ðan 710038, China

    ¡¾Abstract¡¿ AIM: To explore the relationship between hyperª²methylation of the promoter of TSLC1 gene and laryngeal squamous cell cancer. METHODS: Promoter hypermethylation and mRNA expression of TSLC1 gene were respectively detected by methylationª²specific PCR and RTª²PCR in normal laryngeal mucosa (n=4) and laryngeal squamous cell cancer (n=40). RESULTS: Among the 40 patients with laryngeal squamous cell cancer, hypermethylation of TSLC1 promoter was seen in 21 cases (52.5%). There was no significant difference in hypermethylation in relation to pathological grade and clinical stage and classification (P>0.05), but a highly significant difference was observed between the patients with and without lymph node metastasis (N0 and N1) (P<0.05). TSLC1 promoter hypermethylation was observed in human laryngeal squamous cell line Hepª²2. TSLC1 mRNA was not expressed in all laryngeal squamous cell cancers with hypermethylation of TSLC1 promoter and Hepª²2 cells, whereas it was expressed in normal laryngeal mucosa, polyp of vocal cord and laryngeal squamous cell cancers without hyperª²methylation. CONCLUSION: Hypermethylation of TSLC1 promoter is associated with loss of its transcription in laryngeal squamous cell carcinoma.The highª² frequency hypermethylation of TSLC1 promoter illustrates its potential clinical application as tumor marker for diagnosis and prognosis. ......