PDCD4 enhances the inhibitory effect of As2O3 on the growth and NF-κB signaling pathway in neuroblastoma cells / 中华肿瘤杂志

ABSTRACT

Objective@#To investigate the inhibitory effect of programmed cell death factor 4 (PDCD4) on arsenic trioxide (As2O3)-induced cell growth and nuclear factor kappa B (NF-κB) signaling pathway in neuroblastoma.@*Methods@#The PDCD4 overexpression vector was transfected into neuroblastoma cells and detected by fluorescence quantitative PCR and Western blot. As2O3 was used to treat PDCD4 overexpressing neuroblastoma cells. MTT assay was used to measure the proliferation. Colony formation assay was used to determine the cell clone forming ability. Apoptosis was measured by flow cytometry. Western blot was used to detect the expression of NF-κB p65 and cleaved caspase-3 protein in cells.@*Results@#The transfection of PDCD4 overexpression vector significantly increased the expression level of PDCD4 in neuroblastoma cells. The cell survival rates of the control group, PDCD4 group, As2O3 group and As2O3+ PDCD4 group were 100%, (72.14±5.20)%, (62.58±3.14)% and (40.87±2.47)%, respectively. The colony formation rates in these four groups were (91.25±8.36)%, (65.32±7.14)%, (57.23±5.28)% and (37.14±3.64)%, respectively. In addition, the cell apoptotic rates of these four groups were (3.57±0.24)%, (28.64±3.20)%, (36.41±4.58)% and (49.65±5.27)%, respectively. Therefore, overexpression of PDCD4 in the absence or presence of As2O3 inhibited cell proliferation and clone formation ability, while promoted apoptosis. Furthermore, the expression levels of cleaved caspase-3 in the control group, PDCD4 group, As2O3 group and As2O3+ PDCD4 group were 0.21±0.03, 0.30±0.02, 0.43±0.05 and 0.57±0.06, respectively. And the expression levels of NF-κB p65 protein were 0.68±0.04, 0.52±0.03, 0.43±0.04, and 0.32±0.02, respectively. Compared with the control group, the expression levels of NF-κB p65 protein in PDCD4 group, As2O3 group and As2O3+ PDCD4 group were significantly decreased (P<0.05), whereas the expression level of cleaved Caspase-3 protein was significantly increased (P<0.05). The changes in As2O3+ PDCD4 group were more significant than those in PDCD4 group and As2O3 groups (both P<0.05).@*Conclusion@#PDCD4 enhances the inhibitory effect of As2O3 on the growth and NF-κB signaling pathway in neuroblastoma cells.