Effect of actin-related protein 2 modulation of human antigenr R stability on radiotherapy resistance in lung cancer cells
Objective To investigate the effect of actin-related protein 2 on radiotherapy resistance of lung cancer cells through HuR.Methods After treatment with ionizing radiation of 6 Gy,the apoptosis level of lung cancer cells in each group was detected by flow cytometry.The protein expression level of HuR in lung cancer cells was detected by immunoblotting.Radiotherapy resistance of lung cancer cells was indicated by apoptosis level.The half-life of HuR expression level was passed to indicate the stability of HuR.All data were statistically analyzed using prism7,in which the measurement data in line with normal distribution were expressed as mean±standard deviation((x)±s),and the comparison was performed using unpaired two tailed t-test,while the comparison between multiple groups was performed using analysis of variance.Results The expression levels of ARPC2 mRNA and protein in A549(0.43±0.08,1.88±0.15),Calu-1(0.38±0.05,1.90±0.14),HCC827(0.37±0.07,1.89±0.23),MSTO-211H(0.39±0.06,1.95±0.29),NCI-H1299(0.40±0.07,1.92±0.32),NCI-H520(0.42±0.10,1.85±0.30),SK-MES-1(0.44±0.09,1.90±0.30)were higher than in BEAS-2(0.12±0.03,1.19±0.19)and BNHLF(0.08±0.02,1.16±0.20)(t=11.473,14.100,13.825,15.627,18.364,20.594,24.504,9.107,10.335,9.634,11.910,10.882,9.027,10.658,P<0.05).The protein expression level of ARPC2 in the ionizing radiation group(0.81±0.15,1.25±0.25,0.63±0.12,0.51±0.10,0.64±0.15,1.86±0.30,0.85±0.14)was higher than that in the untreated group(0.17±0.04,0.15±0.04,0.16±0.04,0.17±0.05,0.16±0.04,0.17±0.05,0.18±0.06,t=13.037,21.035,13.610,7.331,9.925,28.567,14.814,P<0.05).The apoptosis of lung cancer cells in ARPC2 overexpression group[(16.48±6.11)%,(16.03±5.35)%,(18.28±8.22)%,(24.70±9.71)%,(17.68±9.11)%after ionizing radiation treatment]was lower than that in control group[(47.92±6.58)%,(55.31±6.94)%,(51.29±7.16)%,(51.96±9.17)%,(54.16±2.24)%,t=11.071,14.183,9.579,6.453,12.311,P<0.05].The apoptosis of lung cancer cells in ARPC2 knockdown group[(70.47±8.46)%,(84.16±0.73)%,(76.71±1.87)%,(76.05±0.47)%,(88.07±9.14)%]was higher than that in control group[(55.21±6.29)%,(51.59±7.04)%,(50.07±5.33)%,(47.14±7.53)%,(44.41±9.38)%,t=4.584,14.550,14.912,12.124,10.543,P<0.05].The protein expression levels of HuR,p-HuR,JAK1 and p-STAT3 in ARPC2 overexpression group(0.81±0.11,0.92±0.14,0.55±0.10,0.63±0.12)were higher than those in control group(0.15±0.03,0.14±0.04,0.15±0.03,0.16±0.05,t=18.305,22.614,8.391,11.287,P<0.05).The protein expression levels of p-HuR,JAK1,p-STAT3 in ARPC2 overex-pression group(0.19±0.05,0.15±0.04,0.14±0.03,0.17±0.05)were lower than those in the con-trol group(0.90±0.15,0.85±0.13,0.63±0.12,0.71±0.14,t=14.200,15.628,11.307,13.462,P<0.05).The half-life of HuR in ARPC2 overexpression group[(11.32±0.26),(10.17±0.22),(10.49±0.21),(10.17±0.03),(10.53±0.06)h]was significantly longer than that in the control group[(5.61±1.31),(5.30±2.53),(5.72±1.95),(5.34±0.70),(5.86±1.09)h,t=13.523,6.056,7.691,21.819,13.533,P<0.05].The half-life of HuR in the ARPC2 knockdown group[(2.02±0.71),(2.96±1.23),(2.61±0.68),(3.04±0.82),(2.23±0.22)h]was signifi-cantly shorter than that in the control group[(4.92±1.69),(5.05±0.45),(5.38±0.56),(5.64±0.21),(4.62±0.37)h,t=5.012,5.047,9.941,9.714,17.558,P<0.05].As compared with the control group(47.30±6.59,51.10±4.58,46.44±9.00,53.36±9.56,45.97±2.54),the apoptosis of lung cancer cells was significantly inhibited in the HuR overexpression group(23.01±3.83,17.30±6.59,21.10±4.58,16.44±9.04,23.36±4.56)(t=10.077,13.322,7.935,8.869,13.716,P<0.05).The apoptosis of lung cancer cells in the HuR knockdown group(80.90±17.46、72.24±10.84、77.82±18.9、84.16±10.98、83.50±11.54)was significantly increased as compared with the control group(t=5.693,4.918,5.163,6.025,5.925,P<0.05).Conclusion ARPC2 promotes the radio-therapy resistance of lung cancer cells by improving the protein stability of HuR.
Actin-related protein 2Lung cancerRadiotherapy resistance