论文部分内容阅读
Human papillomaviruses (HPV) are simple,doublestrand,DNA viruses that infect squamous ormucosal epithelia and induce a range of epithelialneoplasms,both benign and malignant. HPVis the major risk factor responsible for the development and progress of most cervical cancersandprecancerous lesions,cervical intraepithelial neoplasia (CIN). More than hundred types of HPV have been characterized,with approximately 40 of them being anogenital types. Of these,15 are associated with cervical carcinoma[1-4].According to the risk of causing cancerous transformation,the types of HPV are divided into two groups: high-risk and low-risk types. High-risk(HR)HPVtypes includesHPV-16,-18,-31,-33,-35,-39,-45,-51,-56,-58,-59,and-68 etc. More recently genotypes 59,68,73,and 82 have been newly identified as high risk,while types 26,53,and 66havebeen designated as probable high risk types.Most of cervical carcinoma was considered to concern with high-risk HPV infection.Therefore it is necessaryto develop effective prophylactic and therapeutic vaccines against HPV infection.However,low-risk(LR)HPVtypes consists of HPV-6,-11,-40,-42,-43,-44,-55 and so on[5-7],whichis associatedmore often with genital warts and benign lesions thanwith cervical cancer. The most frequently associated to malignancies are HR-HPVtypes 16 and 18.And it is reported that HPV16is responsible for nearly 50% andHPV18for nearly 20% ofall invasive cervical cancercases in the world[8].