Yin-Hwa Shih1, Kuo-Chou Chiu2, Tong-Hong Wang3, Wan-Chen Lan4, Bi-He Tsai5, Li-Jia Wu6, Shih-Min Hsia7, Tzong-Ming Shieh8. 1. Department of Healthcare Administration, College of Medical and Health Science, Asia University, Taichung, Taiwan; School of Dentistry, College of Dentistry, China Medical University, Taichung, Taiwan. 2. Division of Oral Diagnosis and Family Dentistry, School of Dentistry, National Defense Medical Center, Taipei, Taiwan; School of Dentistry, College of Dentistry, China Medical University, Taichung, Taiwan. 3. Tissue Bank, Chang Gung Memorial Hospital, Linko, Taiwan. 4. Department of Healthcare Administration, College of Medical and Health Science, Asia University, Taichung, Taiwan. 5. Department of Oral Hygiene, Jen-The Junior College of Medicine, Nursing and Management, Miaoli, Taiwan. 6. Department of Dental Hygiene, College of Health Care, China Medical University, Taichung, Taiwan. 7. School of Nutrition and Health Sciences, Taipei Medical University, Taipei, Taiwan; School of Food and Safety, Taipei Medical University, Taipei, Taiwan; Nutrition Research Center, Taipei Medical University Hospital, Taipei, Taiwan. Electronic address: bryanhsia@tmu.edu.tw. 8. Department of Dental Hygiene, College of Health Care, China Medical University, Taichung, Taiwan; School of Dentistry, College of Dentistry, China Medical University, Taichung, Taiwan. Electronic address: tmshieh@mail.cmu.edu.tw.
Abstract
BACKGROUND/ PURPOSE: Arecoline, the major alkaloid of areca nut, is known to induce reactive oxygen species (ROS) and DNA damage during oral cancer progression. This study aim to evaluate whether melatonin, an antioxidant, supported or repressed the arecoline-induced carcinogenesis phenotypes in oral squamous cell carcinoma (OSCC). METHODS: The cytotoxicity of arecoline or melatonin treatment alone and their co-treatment in the OSCC cell line OEC-M1 were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cell cycle, cell death, and total ROS production were analyzed using flow cytometer. The protein expression was determined using western blot analysis. The genotoxicity and mutation rate were determined using micronucleus assay and hypoxanthine phosphoribosyl transferase (HPRT) forward mutation assay, respectively, in CHO-K1 cells. The ataxia telangiectasia mutated (ATM) promoter activity and DNA repair ability were determined through reporter assay. RESULTS: The result showed that both the arecoline and melatonin induced ROS production and antioxidant enzymes expression. Melatonin treatment enhanced arecoline-induced ROS production, cytotoxicity, G2/M phase arrest, and cell apoptosis in OSCC cells. On the other hand, melatonin treatment activated DNA repair activity to reverse arecoline-induced DNA damage and mutation. CONCLUSION: These results indicated that melatonin is a potential chemopreventive agent for betel quid chewers to prevent OSCC initiation and progression.
BACKGROUND/ PURPOSE:Arecoline, the major alkaloid of areca nut, is known to induce reactive oxygen species (ROS) and DNA damage during oral cancer progression. This study aim to evaluate whether melatonin, an antioxidant, supported or repressed the arecoline-induced carcinogenesis phenotypes in oral squamous cell carcinoma (OSCC). METHODS: The cytotoxicity of arecoline or melatonin treatment alone and their co-treatment in the OSCC cell line OEC-M1 were analyzed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The cell cycle, cell death, and total ROS production were analyzed using flow cytometer. The protein expression was determined using western blot analysis. The genotoxicity and mutation rate were determined using micronucleus assay and hypoxanthine phosphoribosyl transferase (HPRT) forward mutation assay, respectively, in CHO-K1 cells. The ataxia telangiectasia mutated (ATM) promoter activity and DNA repair ability were determined through reporter assay. RESULTS: The result showed that both the arecoline and melatonin induced ROS production and antioxidant enzymes expression. Melatonin treatment enhanced arecoline-induced ROS production, cytotoxicity, G2/M phase arrest, and cell apoptosis in OSCC cells. On the other hand, melatonin treatment activated DNA repair activity to reverse arecoline-induced DNA damage and mutation. CONCLUSION: These results indicated that melatonin is a potential chemopreventive agent for betel quid chewers to prevent OSCC initiation and progression.