Evaluation of dental pulp tissue damage caused by antineoplastic drugs and search for effective approaches to cariogenic bacteria

Research Project

Project/Area Number	17K11974
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Research Field	Orthodontics/Pediatric dentistry
Research Institution	The Nippon Dental University
Principal Investigator	KAWAKAMI TOMOMI 日本歯科大学, 生命歯学部, 准教授 (30277595)
Co-Investigator(Kenkyū-buntansha)	苅部洋行日本歯科大学, 生命歯学部, 教授 (50234000)
Project Period (FY)	2017-04-01 – 2020-03-31
Project Status	Completed (Fiscal Year 2019)
Budget Amount *help	¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000) Fiscal Year 2019: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000) Fiscal Year 2018: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000) Fiscal Year 2017: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
Keywords	小児 / 歯の形成 / 抗腫瘍薬 / シクロフォスファミド / マウス / 小児がんサバイバー / 小児がん / Streptococcus Mutans / Streptococcus mutans / 齲蝕原因菌 / アルキル化剤 / 歯髄腔形態
Outline of Final Research Achievements	The aim of this study was to investigate the effect of Cyclophosphamide(CY) on dental pulp tissues in growing mice. In the experimental group, morphological changes of odontoblasts were observed, and CY inhibited the regular formation of the roots of molars. We also investigated the effect of antitumor agents on Streptococcus Mutans, which is a cariogenic bacterium. There were differences in the response to SM bacteria depending on the type of antitumor drug. From the above results, the treatment of pediatric cancer would effect on the dental pulp tissues, and also may change the circumstance of the caries- causing bacteria. These results suggests that dental follow-up is important during and after childhood cancer treatment for childhood cancer patients and survivors.
Academic Significance and Societal Importance of the Research Achievements	近年の臨床報告からは，小児がん治療後の長期生存者では晩期合併症である歯の形成異常や口腔疾患のリスクが高まることが明らかとなっている。小児期において化学療法が早期に開始されれば，より多くの歯胚が影響をうけ，障害のおこる歯数や程度も重症化すると考えられる。また，障害の程度は，抗腫瘍薬の投与期間，間隔，薬剤の種類やその組合せなどが関係すると予想されるが，個々の薬剤に対する細胞の感受性時期や障害程度などのデータを蓄積していくことも，将来小児がん治療のプロトコールを改良していく際の資料として重要である。