Related Experiment Video
Updated: Jul 5, 2026
Analysis of Combinatorial miRNA Treatments to Regulate Cell Cycle and Angiogenesis
Published on: March 30, 2019
[Effects of RNA interference of COX-2 gene expression on malignant proliferation of A549 cells in vitro]
Wei-Ying Li1, Hui Wang, Bai-Tang Lai
1Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing 101149, China.
Objective:
To investigate the inhibition of COX-2 gene expression and its effects on malignant proliferation of human lung adenocarcinoma A549 cells after interfering at different target sites in vitro.
Methods:
The 3rd, 7th and 10th exon of COX-2 were selected as the targets and three COX-2 siRNA expression vectors with human U6 promoter were constructed. Three siRNA expression vectors and two vacant vectors were transfected into A549 cells expressing COX-2 with lipofectamine, respectively. The transfected cell strains were constructed and the change of COX-2 expression levels was examined by Western blot and RT-PCR. The effects on the proliferation of A549 cells after interfering at different target sites were studied by cell growth curve and colony formation assay in vitro.
Results:
The three siRNAs and U6 promoter were validated by PCR, restriction endonuclease digestion, DNA sequencing and BLAST alignment, and cloned into the pEGFP vector. The cell strains transfected were named as A549-3, A549-7, A549-10, A549-p and A549-pU6, respectively. A549-p cells showed expression of GFP and A549-3, A549-7, A549-10, A549-p and A549-pU6 cells did not show at 24, 48 and 72 hours after transfection. The results of RT-PCR and Western blot showed an inhibition of COX-2 expression after interfering at three target sites (3rd, 7th and 10th exons). In contrast to A549 cells, the levels of COX-2 mRNA of A549-3, A549-7 and A549-10 cells were reduced by 10.6%, 33.4% and 61.2%, respectively. The levels of COX-2 protein of A549-3, A549-7 and A549-10 cells were reduced by 26.7%, 44.7% and 56.2%, respectively. The results of cell growth curve and colony formation assay showed a slowing down of the growth of A549-10 cells and reduction of their colony formation rate. The other two targets had no apparent effect on the growth of A549 cells.
Conclusion:
There is a significant inhibiting effect of RNA interference on the malignant proliferation of A549 cells in vitro, and the most striking effect can be seen when the 10th exon of COX-2 is taken as the interference target.
Insights
RNA interference targeting the 10th exon of cyclooxygenase-2 (COX-2) significantly inhibits lung adenocarcinoma A549 cell proliferation. This study demonstrates COX-2 siRNA
Area of Science:
- Molecular biology
- Cancer research
- Gene expression analysis
Context:
- Lung adenocarcinoma is a major cause of cancer mortality.
- Cyclooxygenase-2 (COX-2) is implicated in tumor progression.
- Targeting COX-2 offers a potential therapeutic strategy.
Purpose:
- To investigate the efficacy of RNA interference (RNAi) in inhibiting COX-2 gene expression.
- To assess the impact of targeting different COX-2 exons on A549 cell proliferation.
- To identify the optimal target site for COX-2-mediated anti-proliferative effects.
Summary:
- Three small interfering RNA (siRNA) expression vectors targeting the 3rd, 7th, and 10th exons of COX-2 were constructed and transfected into A549 cells.
- RT-PCR and Western blot analysis confirmed significant inhibition of COX-2 mRNA and protein levels, with the 10th exon target showing the greatest reduction.
- Cell proliferation assays (growth curve and colony formation) revealed that targeting the 10th exon markedly reduced A549 cell growth and colony formation.
Impact:
- RNA interference targeting COX-2 demonstrates significant anti-proliferative effects on lung adenocarcinoma cells in vitro.
- Targeting the 10th exon of COX-2 is the most effective strategy for inhibiting A549 cell malignant proliferation.
- These findings support the potential of COX-2 as a therapeutic target in lung adenocarcinoma.
More Related Videos
Related Concept Videos
02:15Experimental RNAi
01:23RNA Interference
This process occurs naturally in cells, often through the activity of genomically-encoded microRNAs. Researchers can take advantage of this mechanism by introducing synthetic RNAs to deactivate specific genes for research or therapeutic purposes. For example, RNAi could be used...
01:22MicroRNAs
02:34Inhibition of Cdk Activity