<正> Objective: To acquire a ribozyme against the E6 gene of human papillomaviruses type 16 （ HPV16E6） and investigate its effects on the phenotypes and gene expression of cervical cancer cell line. Methods: Anti-HPV16E6 ribozyme （ HRz） was designed by computer programs and its activity identified by cleavage experiment in vitro before its transfection via lipofectin into CaSKi cells with the empty eucaryotic expression plasmid transfection of the cells also performed

the resultant cells designated as CaSKi-R

CaSKi-P respectively. The morphology and the soft agar forming ability were studied in CaSKi cells and the transfected cells

and the expression of E6

proliferating cell nuclear antigen （ PCNA） and C-erbB-2 genes assayed by flow cytometry. The tumorgenicity of each cell line was evaluated in nude mice receiving inoculations of CaSKi

CaSKi-R and CaSKi-P cells separately

while in one group

both CaSKi and CaS-Ki-R cells were inoculated on different sides of the mice. Results: HRz was able to cleave H