Effects of interleukin-21 gene combined with different doses of γ-ray radiation on growth of breast carcinoma cells

Objective To study the effect of recombinant adenovirus vector carrying interleukin-21 gene(Ad-IL-21) combined with different doses of γ-ray radiation on the growth of breast neoplasms.

Methods MCF-7 cells were transfected by Ad-IL-21 and exposed from 0 to 10 Gy ¹³⁷Cs γ-ray 6 h after transfection. The cohorts were divided into 5 groups:blank control group, adenovirus vector containing β-galactosidase gene(Ad-LacZ) group, Ad-IL-21 group, γ-ray radiation group and Ad- IL-21 combined with radiation group. The inhibition rates of MCF-7 cells were detected by MTT assay.

Results MCF-7 cells transfected with Ad- IL-21 were inhibited significantly greater than that of Ad-LacZ(F=26.34, P < 0.05). The inhibition rates of γ-ray radiation group and Ad-IL-21 combined with radiation group were significantly higher than that of Ad- IL-21 group(F=23.51, F=27.55, both P < 0.05)and the inhibition rate increased when γ-ray radiation doses increased. The inhibition rate of Ad- IL-21 combined with radiation group was higher than that of γ-ray radiation group at the same dose. The inhibition rate of Ad- IL-21 combined with radiation group was the highest, which was significantly higher than that of Ad- IL-21 group and γ-ray radiation group(F=35.68, F=38.67, both P < 0.05).

Conclusion The recombinant Ad- IL-21 transfection combined with γ-ray radiation shows the synergism for the inhibition of the growth of MCF-7 cells.