title: Spinal cord biological safety of image-guided radiation therapy versus conventional radiation therapy.
abstract: Tumor models were simulated in purebred Beagles at the T9-10 levels of the spinal cord and treated with spinal image-guided radiation therapy or conventional radiation therapy with 50 or 70 Gy total radiation. Three months after radiation, neuronal injury at the T9-10 levels was observed, including reversible injury induced by spinal image-guided radiation therapy and apoptosis induced by conventional radiation therapy. The number of apoptotic cells and expression of the proapoptotic protein Fas were significantly reduced, but expression of the anti-apoptotic protein heat shock protein 70 was significantly increased after image-guided radiation therapy compared with the conventional method of the same radiation dose. Moreover, the spinal cord cell apoptotic index positively correlated with the ratio of Fas/heat shock protein 70. These findings indicate that 3 months of radiation therapy can induce a late response in the spinal cord to radiation therapy; image-guided radiation therapy is safer and results in less neuronal injury compared with conventional radiation therapy.
authors.affiliation: The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi 830000, Xinjiang Uygur Autonomous Region, China ; People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi 830000, Xinjiang Uygur Autonomous Region, China.
authors.forename: Wanlong
authors.initials: W
authors.lastname: Xu
authors.affiliation: The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi 830000, Xinjiang Uygur Autonomous Region, China.
authors.lastname: Xilinbaoleri
authors.affiliation: The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi 830000, Xinjiang Uygur Autonomous Region, China.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.affiliation: The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi 830000, Xinjiang Uygur Autonomous Region, China.
authors.forename: Ruozheng
authors.initials: R
authors.lastname: Wang
authors.affiliation: The Affiliated Tumor Hospital of Xinjiang Medical University, Urumqi 830000, Xinjiang Uygur Autonomous Region, China.
authors.forename: Jingping
authors.initials: J
authors.lastname: Bai
keywords: Fas; Image-guided radiation therapy; apoptosis; biological safety; conventional radiation therapy; heat shock protein 70; neurons; spinal cord; tumor; vertebral body