Silencing human papillomavirus E6/E7 oncoprotein and enterovirus 71 IRES by RNA interference for tumor therapy and virus infection

• Main Authors: Chih-Liang Chiu, 邱志亮
• Other Authors: W.T. Chang
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/78006058190805929307

碩士 === 國立成功大學 === 生物化學研究所 === 95 === Human papillomavirus, causative agent of cervical cancers, encodes the E6 and E7 oncogenes, whose simultaneous expression is pivotal for malignant transformation and maintenance. The E6 and E7 oncoproteins of high-risk HPV, particularly HPV 18 and 16, bind respectively to the p53 and Retinoblastoma (Rb) tumor suppressor proteins, which are involved in the regulation of cell growth. RNA interference (RNAi) is a sequence-specific RNA degradation process in the cytoplasm of eukaryotic cells that is induced by double-stranded RNA. Inhibition of HPV expression by means of RNAi has been reported in many papers. In this study, we have screened the effective siRNA/shRNA by siRNA validation system. By transfection of these shRNA to cervical cancer cell, we found that E6 and E7 shRNA induced accumulation of p53 by decreasing mRNA encoding E6 and E7 protein. We thought that HPV E6 and E7 siRNA as a candidate for gene-specific therapy for HPV-related cervical cancer. Since its discovery in 1969, EV71 has been recognized as a frequent cause of epidemics of hand-foot-mouse disease (HFMD) associated with several neurological sequelae in a small proportion of cases. In 1998, the largest EV71 outbreak in Taiwan, more than 90000 children with HFMD had been reported. Internal ribosomal entry site (IRES), structured RNA sequence, was thought that it is essential to recruit and activate translation machinery. We focus on prevention of EV71 infection by using small interfering RNA to inhibit IRES of EV71. we have screened effective siRNA against the expression of Taiwan/4643 EV71 IRES expression cassettes by screening system. We attempt to use siRNA we selected to knockdown expression of EV71 IRES. Then, the cell, EV71 infection, would be protected from death, and decreased the activation of EV71.