Effects of X-ray and heavy-ion beam on the DNA and genes in head and neck carcinomas

2004 Fiscal Year Final Research Report Summary

• Project/Area Number: 15592135
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Surgical dentistry
• Research Institution: TOKYO DENTAL COLLEGE
• Principal Investigator: SHIBAHARA Takahiko TOKYO DENTAL COLLEGE, DEPARTMENT OF DENTISTRY, PROFFESSOR, 歯学部, 教授 (50178919)
• Co-Investigator(Kenkyū-buntansha): MIZOE Zyun-etsu NATIONAL INSTITUTE OF RADIATION SCIENCES, HOSPITAL, DIRECTOR, 重粒子医科学センター病院, 病院長 (80091510) ; NOMURA Takeshi TOKYO DENTAL COLLEGE, DEPARTMENT OF DENTISTRY, LECTURER, 歯学部, 助手 (60328268)
• Project Period (FY): 2003 – 2004
• Keywords: Heavy ion beams / head and neck cancer / malignant melanoma / squamous cell carcinoma / adeno carcinoma / damage of DNA / cahnge of gene expression / X-ray

Research Abstract

Effects of X-ray and heavy ion beam on the DNA and genes in head and neck carcinoma cells were examined. Four head and neck cancer cell lines, squamous cell carcinoma, salivary gland cancer, malignant melanoma, normal keratinocyte), were treated with 1,4,and 7 GyE of carbon-ray and 1,4,and 8 Gy of X-ray and DNA, respectively. DNA and RNA in the treated cells were extracted and purified. PCR-LOH analysis with 6 micro-satellite regions on chromosome 17 was performed for DNA structural damages, and then micro-array analysis was performed to reveal the changes of gene expressions in the cells. PCR-LOH analysis detected many LOH in the cells treated by radiation, indicating that most of the damage by X-ray occurred on the single chain of the two DNA chains. However, Carbon-ray caused the homo-deletion, which means the deletion of the both of the double chains. Moreover, microarray analysis indicated that Carbon-ray caused not only suppression but also up-regulation of the many gene-expressions. Especially, the gene group of "structural protein" strongly reacted, suggesting the cell damage and resistant to the Carbon-ray. "Microtubular Dynamics" and "Motor" group genes were suppressed by Carbon-ray, resulting in the disorder in the intracellular transport systems and chromosome separation.