To observe the inhibitory effect of CTNNB1 gene expression and cell proliferation of the human colon cancer cell line SW480 caused by CTNNB1-targeted ShRNA.

The shRNA against CTNNB1 was constructed and transfected into SW480 cells. The down-regulations of CTNNB1 expressions were detected by RT-PCR and Western blotting analysis. The cell proliferation was determined by soft agar colony formation assay. The effect of these shRNAs on cell cycle distribution and apoptosis was examined by flow cytometry.

The CTNNB1-shRNA efficiently suppressed the expression of CTNNB1 mRNA and protein, P<0.05. The expression inhibition rates were 43.87% and 45.16% at the mRNA and protein level respectively. The MTT assay indicated that the specific shRNA resulted in significant inhibition of cell growth on the culture plates on a time-dependent manner. Seventy-two hours after transfection, the cell viability of CTN group was 46.4%, which was of statistical significance when compared with that of blank control group, P<0.05. Moreover, the cancer cells showed significant G0/G1 arrest and increased apoptosis in the CTN group by flow cytometry, P<0.05.

The specific CTNNB1-shRNA may down-regulate the expression of CTNNB1 gene, increase apoptosis and inhibit the growth of SW480 cells.