Areeya Arayataweegool1, Ratakorn Srisuttee2, Patnarin Mahattanasakul3,4, Napadon Tangjaturonsasme3, Virachai Kerekhanjanarong3, Nakarin Kitkumthorn5, Apiwat Mutirangura6. 1. Program of Medical Science, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. 2. Faculty of Medicine, King Mongkut's Institute of Technology Ladkrabang, Bangkok, Thailand. 3. Department of Otolaryngology, Head and Neck Surgery, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand. 4. Department of Otolaryngology, Head and Neck Surgery, King Chulalongkorn Memorial Hospital, Thai Red Cross Society, Bangkok, Thailand. 5. Department of Oral Biology, Faculty of Dentistry, Mahidol University, Bangkok, Thailand. 6. Center of Excellence in Molecular Genetics of Cancer and Human Diseases, Department of Anatomy, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.
Abstract
OBJECTIVE: Alteration of long interspersed element-1 (LINE-1) methylation in peripheral blood mononuclear cells (PBMCs) has been simultaneously activated to breast carcinogenesis due to its secretion. To evaluate the effect in head and neck squamous cell carcinoma (HNSCC), LINE-1 methylation levels and patterns have been measured both in vitro and in vivo. METHODS: Analysis of LINE-1 methylation in cocultured models between HNSCC cell lines and normal PBMCs was performed. The observation of PBMCs of HNSCC patients compared to PBMCs of normal controls was performed using the semiquantitative combined bisulfite restriction analysis technique. RESULTS: Downregulation of LINE-1 methylation was significantly found in the PBMCs cocultured with all HNSCC cell lines compared to normal PBMCs. Likewise, a reduction in LINE-1 methylation levels was observed in PBMCs of HNSCC compared to normal PBMCs (p < 0.0001). Receiver operating characteristic analysis demonstrated the potential of the unmethylated alleles (u Cu C) of LINE-1 for distinguishing the PBMCs of HNSCC patients from normal controls with 100% sensitivity and specificity. CONCLUSION: Our data supported that the alteration of LINE-1 methylation levels in PBMCs was influenced by HNSCC secretions. Moreover, the unmethylated LINE-1 allele of PBMCs was proved to be an effective tumor marker and possesses a potential as HNSCC diagnostic tool.
OBJECTIVE: Alteration of long interspersed element-1 (LINE-1) methylation in peripheral blood mononuclear cells (PBMCs) has been simultaneously activated to breast carcinogenesis due to its secretion. To evaluate the effect in head and neck squamous cell carcinoma (HNSCC), LINE-1 methylation levels and patterns have been measured both in vitro and in vivo. METHODS: Analysis of LINE-1 methylation in cocultured models between HNSCC cell lines and normal PBMCs was performed. The observation of PBMCs of HNSCC patients compared to PBMCs of normal controls was performed using the semiquantitative combined bisulfite restriction analysis technique. RESULTS: Downregulation of LINE-1 methylation was significantly found in the PBMCs cocultured with all HNSCC cell lines compared to normal PBMCs. Likewise, a reduction in LINE-1 methylation levels was observed in PBMCs of HNSCC compared to normal PBMCs (p < 0.0001). Receiver operating characteristic analysis demonstrated the potential of the unmethylated alleles (u Cu C) of LINE-1 for distinguishing the PBMCs of HNSCC patients from normal controls with 100% sensitivity and specificity. CONCLUSION: Our data supported that the alteration of LINE-1 methylation levels in PBMCs was influenced by HNSCC secretions. Moreover, the unmethylated LINE-1 allele of PBMCs was proved to be an effective tumor marker and possesses a potential as HNSCC diagnostic tool.