title: Effects of irradiation on growth and differentiation-related gene expression in osteoblasts.
abstract: Osteoblasts are bone-forming cells that are responsible for the production of bone extracellular matrix. Osteoradionecrosis is a complication of radiation therapy for carcinoma of the head and neck that occurs in 3% to 8.2% of irradiated patients. The irradiation effect on osteoblast differentiation has not been fully elucidated. The objective of our research was to elucidate the effects of radiation on the growth and differentiation-related gene expression in osteoblast in vitro. Three differentiation-related genes, alkaline phosphatase, type I collagen, and osteocalcin, were tested in our experiment. The results showed that radiation inhibited the proliferation of the osteoblasts in a dose-dependent manner and induced G2/M cell cycle arrest. Irradiation, 4 and 8 Gy, enhanced the differentiation-related gene expression of MC3T3-E1 cells 7 days after irradiation. However, the differentiation-related gene expression was decreased 21 days after irradiation in the 4- and 8-Gy groups. This work presents the dynamic phenotypic expression changes of osteoblastic cells after x-ray irradiation.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Shanghai Jiao-tong University, School of Medicine, Shanghai Ninth People's Hospital, Shanghai, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: He
authors.forename: Weiliu
authors.initials: W
authors.lastname: Qiu
authors.forename: Zhiyuan
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zhonghe
authors.initials: Z
authors.lastname: Wang
authors.forename: Xiuli
authors.initials: X
authors.lastname: Zhang
authors.forename: Yue
authors.initials: Y
authors.lastname: He
mesh_terms: D000469:Alkaline Phosphatase / Q000235:genetics; D000704:Analysis of Variance; D000818:Animals; D002453:Cell Cycle; D002454:Cell Differentiation / Q000235:genetics* / Q000528:radiation effects*; D049109:Cell Proliferation / Q000528:radiation effects*; D003094:Collagen / Q000235:genetics; D004307:Dose-Response Relationship, Radiation; D005786:Gene Expression Regulation / Q000528:radiation effects*; D051379:Mice; D010006:Osteoblasts / Q000528:radiation effects*; D015675:Osteocalcin / Q000235:genetics; D010641:Phenotype; D014965:X-Rays
chemical_list: D015675:Osteocalcin; D003094:Collagen; D000469:Alkaline Phosphatase