Regulatory effect of overexpressed Id3 on the expression of β-catenin in different tumor cells
10.16571/j.cnki.1008-8199.2017.05.004
- VernacularTitle:Id3过表达对不同肿瘤细胞中β-catenin的调节
- Author:
Qinfei ZHAO
;
Fangfang CHEN
;
Yuzhong XU
;
Haiyong WANG
;
Xiaolong GUAN
;
Ning SUN
;
Ang LI
;
Shusheng SONG
;
Wei YU
;
Xiaojun LI
- Keywords:
Inhibitor of differentiation 3;
β-catenin;
Tumor cell
- From:
Journal of Medical Postgraduates
2017;30(5):464-469
- CountryChina
- Language:Chinese
-
Abstract:
Objective The inhibitor of differentiation 3 (Id3) is an important transcriptional regulation factor, which participates in tumorigenesis, cell proliferation, and cell apoptosis.β-catenin, as a central molecule of the Wnt signaling pathway, is critical for tumor development.This study aimed to evaluate the expressions of these two molecules and the regulatory effect of Id3 on β-catenin in different tumor cells.Methods Total RNA was extracted using the Trizol Reagent.The relative mRNA expression levels of Id3 and β-catenin in tumor cells were detected by quantitative real-timePCR(qRT-PCR).The recombinant eukaryotic expression vector pEGFP/Id3 with the human Id3 gene was transfected into A549, A549/ DDP and SW-480 cells using the non-liposome-mediated method.The protein expressions of Id3 and β-catenin were determined by Western blot.Results The expression of Id3 was significantly lower in the colorectal cancer cell lines SW-480 and HT-29 than in A549 and other tumor cells (P<0.05), but remarkably higher in nasopharyngeal carcinoma CNE and 5-8F cells than in other tumor cells (P<0.05).The expression of β-catenin was the highest in SW-480in comparison withother malignant tumor cells(P<0.05), and the second highest was in gastric cancer AGS and colorectal cancer HT-29 cell lines, but low in H446, A549, SPC-A-1, A549/DDP, and SK-MES-1 cell lines and extremely low or almost absent in CNE and 5-8F cells (P<0.05).After transfected with pEGFP/Id3, the cells showed a decreased volume, wrinkled membrane and absent refraction under the fluorescence microscope, which, however, were not observed in most of the cells transfected with the empty vector pEGFP.Compared with the control, the Id3/pEGFP group showed remarkably increased expressions of Id3 mRNA in the A549, A549/DDI, and SW-480 cells (1.24±0.12 vs 193.12±2.80, 1.09±0.11 vs 188.30±2.60, and 0.92±0.29 vs 19.08±0.59, P<0.01), and the expression of β-catenin was significantly down-regulated in the transfected SW-480 cells with an overexpression of Id3 (0.98±0.05 vs 0.32±0.03, P<0.01), but exhibited no statistically significant differences from those in the transfected A549 and A549/DDP cells (0.98±0.07 vs 1.04±0.08 and 0.98±0.05 vs 0.32±0.03, P>0.05).Western blot showed the same results.Conclusion The expression levels of Id3 and β-catenin vary in different tumor cell lines.Anabnormally high level of β-catenin is an important risk factor for colorectal cancer, and the down-regulatedexpression of β-catenin after eogenous transfection of Id3 may provide some new ideas for target gene therapies of colorectal cancer.
