Inhibitory Effect of Polyphyllin D on Proliferation of Human Colon Cancer Cell Line SW480 via the MicroRNA-21/Phosphatase and Tensin Homolog Deleted on Chromosome 10

Abstract

To evaluate the effects of polyphyllin D on the proliferation and apoptosis of human colon cancer SW480 cell lines and to reveal whether this process is mediated by the micro ribonucleic acid-21/phosphatase and tensin homolog deleted on chromosome 10 pathway. Human colon cancer SW480 cells were transfected with micro ribonucleic acid-21-mimic or mimic-negative control and treated with polyphyllin D at different concentrations (control, 0.25, 0.5, 1 and 2 μM) for 24 h or 48 h. Compared with control polyphyllin D group, the viability of human colon cancer SW480 cells significantly declined but the apoptosis rate significantly rose in 0.5 μM polyphyllin D group and the colony number of SW480 cells significantly decreased in 0.25 μM polyphyllin D group (p<0.05). Compared with control group, 2 μM polyphyllin D group had significantly increased protein expressions of Bcl-2 associated X protein and cleaved caspase-3, but decreased protein expression of B-cell lymphoma-2 in SW480 cells (p<0.001). The protein levels of micro ribonucleic acid-21 and phosphorylated-protein kinase B in SW480 cells were significantly lower, while the phosphatase and tensin homolog deleted on chromosome 10 messenger ribonucleic acid and protein levels were higher in 2 μM polyphyllin D group than those in control group (p<0.001). However, the protein expression of protein kinase B was not changed in 2 μM polyphyllin D group (p>0.05). After transfection with micro ribonucleic acid-21-mimic, the level of micro ribonucleic acid-21 in SW480 cells was significantly higher, while the phosphatase and tensin homolog deleted on chromosome 10 messenger ribonucleic acid and protein levels were significantly lower than those in control group (p<0.001). Compared with control group, the antiproliferative and pro-apoptotic effects of polyphyllin D on SW480 cells were reversed by transfection with micro ribonucleic acid-2-mimic (p<0.001). Polyphyllin D inhibits proliferation and induces apoptosis of human colon cancer SW480 cells via the micro ribonucleic acid-21/phosphatase and tensin homolog deleted on chromosome 10 pathway.