KAI1 gene is a metastasis suppressor gene discovered in 1995, the product of which is a member of the transmembrane-4 superfamily. The expression of KAI1 gene correlate with metastasis of almost all cancer. But some results of some study are different. This article reviewed the study of the genomic structure of KAI1 gene and the relationship between KAI1 gene and neoplastic invasion, metastasis, prognosis.

Objective From knowledge,attitude,practice,and environment dimensions to investigate the status of oral health self-management in adolescents receiving fixed orthodontics and analyze its influencing factors.Methods A self-designed questionnaire developed from an evaluation index system for adolescents receiving fixed orthodontics was used to investigate 300 adolescent orthodontic patients in a stonatological hospital in Shanghai,who were 11 to 17 years old,receiving fixed orthodontics for more than three months.Results For adolescents receiving fixed orthodontics,self-management knowledge score was 0.99-±0.18,attitude score was 0.92±0.13,practice score was 1.11±0.21,and environment score was 0.66±0.15.The scores of oral health self-management knowledge,attitude,practice,and environment were significantly different between boys and girls(P＜0.01).There was significant difference in the scores of oral health self-management practice in adolescents with different age(P＜0.05).The scores of oral health selfmanagement were significantly different for adolescents with different stages of receiving fixed orthodontics(P＜0.05).Multiple stepwise regression analysis showed that oral health self-management status was affected by gender and age.Conclusion The oral health self-management status of adolescents receiving fixed orthodontics needs to be further improved.Female adolescents have better oral health self-management status than male adolescents.The increasing of age cannot necessarily improve self-management status.Orthodontic time has the greatest influence on oral health self-management practice.Medical staffs can provide targeted health education and guidance based on the status and influencing factors for adolescent orthodontic patients in order to improve their oral health self-management status.