Synergistic effects of nuclear factor-kappa B inhibition by small interferece RNA on 131I therapy in differentiated thyroid cancer cells
10.3760/cma.j.issn.2095-2848.2013.03.013
- VernacularTitle:小干扰RNA抑制核因子-κB增强131I治疗甲状腺癌疗效的研究
- Author:
Yajing HE
;
Zhaowei MENG
;
Jian TAN
- Publication Type:Journal Article
- Keywords:
Thyroid neoplasms;
Cell apoptosis;
Iodine radioisotopes;
RNA,small interfering;
Nuclear factor-kappa B
- From:
Chinese Journal of Nuclear Medicine and Molecular Imaging
2013;(3):207-212
- CountryChina
- Language:Chinese
-
Abstract:
Objective To study the effect of nuclear factor-kappa B (NF-κB) inhibition by small interference RNA (siRNA) on the apoptosis of DTC cells treated by 131 I.Methods DNA binding assay was performed at 24 h after 131I treatment (2 × 104 MBq/L) on KTC-1 cells.The cell survival assay was conducted at 48 h after 131 I treatment.Western blot was used to detect the changes of NF-κB p65 at 6 h after 131I treatment,and the changes of anti-apoptotic factors and apoptotic key factors at 24 h after 131 I treatment.The anti-apoptotic factors included in this study were X chromosome-linked inhibitor of apoptosis (XIAP),cellular inhibitor of apoptosis 1 (cIAP1) and B-cell lymphoma extra large (Bcl-xL),and the apoptotic key factors were caspase 3 and poly-ADP-ribose polymerase (PARP).A total of 4 groups were studied for the detection of p65 and anti-apoptotic factors by Western blot:no oligonucleotide transfection control group (A),no oligonucleotide transfection + 131I group (B),scrambled oligonucleotides transfection + 131I group (C) and p65 siRNA transfection + 131I group (D).Another 6 groups of studies were:oligonucleotide transfection control group (1),scrambled oligonucleotides transfection group (2),p65 siRNA transfection group (3),no oligonueleotide transfection + 131I group (4),scrambled oligonucleotides transfection +131I group (5) and p65 siRNA transfection + 131I group (6).One-way analysis of variance and q test were performed for statistical analysis.Results The results of DNA binding assays for the 6 groups (1,2,3,4,5,6) were (100.00 ± 11.65)％,(96.00 ± 17.98)％,(9.28 ±5.01)％,(322.72 ±50.81)％,(311.36 ±44.81)％ and (36.96 ± 15.66)％,respectively (F =137.74,P ＜0.01).NF-κB functions were strengthened with 131 I treatment (qgrouo 4∶1 =10.90,qroup 5∶2 =11.38,both P ＜ 0.01).However,NF-κB p65 siRNA transfection could inhibit NF-κB functions (qgroup1∶3 =18.25,qgroup4∶6 =13.71,both P ＜0.01).Cell survival rates of the 6 groups were (100.00 ± 11.65)％,(96.32 ± 9.44)％,(70.88 ±7.41)％,(64.16 ±9.50)％,(62.24 ±9.37)％ and (28.64 ±6.74)％ (F=52.76,P＜0.01).There were significant differences between groups 3 and 6,groups 4 and 6 (q =10.76 and 7.79,both P ＜ 0.01).Western blot results showed that the expression of NF-κB p65 in the 4 groups (A,B,C,D) were (56.60 ±7.37)％,(111.07 ± 13.31)％,(113.16± 15.04)％ and (12.46 ±2.74)％,respectively (F=60.17,P ＜ 0.01).The t65 levels increased with 131 I treatment (qgroup B∶A =6.20,qroup c∶ A =5.85,both P ＜0.01); while decreased significantly using NF-κB p65 siRNA transfection (qgroup B:D =-12.57; qgroupC∶D =11.41,both P ＜ 0.01).Western blot results showed that XIAP,cIAP1 and Bcl-xL in the 4 groups were (17.59±1.96)％,(16.45± 1.85)％ and (19.92 ±2.22)％; (98.37± 17.92)％,(109.81 ±19.16)％ and (95.59 ±22.20)％ ; (98.43 ±18.71)％,(98.86± 15.88)％ and (100.99 ±21.70)％ ;(7.00 ± 0.95) ％,(5.86 ± 0.35) ％ and (9.52 ± 0.90) ％,respectively (F =44.22,56.51 and 29.11,all P ＜ 0.01).131 I treatment induced higher expression of all the 3 genes (qgroup B∶ A =7.76,8.40 and 5.88,all P ＜0.01),while NF-κB p65 siRNA transfection,on the contrary,reduced the expression of all the 3 genes (qgroupB:D =8.82,9.40 and 6.71,all P ＜0.01).There were significant differences of p19,p17,p116 and p89 in the 6 groups(F =39.03,48.45,32.56,52.20,all P ＜ 0.01),especially among group 3,4 and 6 (q =3.18-9.98,all P ＜ 0.05).Conclusions 131I could activate NF-κB function and enhance the expressions of anti-apoptotic factors.NF-κB p65 siRNA transfection could effectively suppress this effect and therefore magnify 131I induced apoptosis in DTC cells.
