Interference of RNAi to CD133 gene and the comparison of the interferential effects in KATO-III cells of human gastric cancer

Objective To compare the inhibition effects of three synthesized fragments used in small interfering RNA(siRNA) against CD133 gene in KATO-Ⅲ gastric cancer cells,and to study effects of suppressed CD133 on the proliferating ability of intervened cells.Methods Three fragments of siRNA were designed and synthesized targeted at the mRNA of CD133.Cell fluorescence counting under confocal laser scanning microscope was used to determine the transfection efficiency after transfection with the CD133FITC-siRNA.The knock-down effect of the CD133 gene was detected by RT-PCR and Western blotting.CCK-8 (cell counting kit-8 assay) was performed to measure the variation of the cell proliferative viability after the above-mentioned treatment.Results The transfection efficiency of siRNA was (85 ± 8) ％ in KATO Ⅲ Gastric cacer cell.All these three fragments of CD133 siRNA effectively inhibited the expression of CD133 gene,the inhibition rate being (11 ± 2) ％,(19 ± 2) ％,(24 ± 3) ％respectively.Compared with the control group,the cell proliferation viability was restrained (42 ± 4)％ in CD133siRNA-3 group (P ＜0.05).Conclusions CD133siRNAs were successfully transfected into KATO Ⅲ Gastric cacer cells and repressed the expression of CD133.Meanwhile,the CD133siRNA fragment 3 was screened from three CD133 siRNA,which has the best inhibition effect.The results provide preliminary evidence for the intereference of CD133+ gastric cancer cells subsequently. Key words: Stomach neoplasms;  Carcinoma;  Stem cells;  RNAi;  CD133