Intracellular expression of the T-cell factor-1 RNA aptamer as an intramer

Area of Science:

• Molecular Biology
• Cancer Research
• Gene Therapy

Background:

• T-cell factor (TCF)-1 protein, complexed with beta-catenin, is crucial for gene regulation in development and cancer.
• Previous work identified an RNA aptamer that binds TCF-1's DNA-binding domain, inhibiting its DNA binding in vitro.

Purpose of the Study:

• To develop an RNA expression vector for stable intracellular expression of an RNA aptamer targeting TCF-1.
• To evaluate the efficacy of this RNA aptamer intramer in modulating TCF/beta-catenin transcriptional activity and its impact on colon cancer cells.

Main Methods:

• Constructed an RNA expression vector for stable, intracellular expression of an RNA aptamer fused to a transcript.
• Assessed TCF/beta-catenin transcriptional activity using luciferase assays.
• Quantified the expression of target genes (cyclin D1, matrix metalloproteinase-7).
• Evaluated the effect of the RNA intramer on HCT116 colon cancer cell growth and tumorigenicity.

Main Results:

• High-level expression of the RNA aptamer as an intramer was achieved within mammalian cells.
• The RNA intramer significantly inhibited TCF/beta-catenin transcription activity.
• Expression of target genes like cyclin D1 and matrix metalloproteinase-7 was modulated.
• A notable reduction in the growth rate and tumorigenic potential of HCT116 colon cancer cells was observed.

Conclusions:

• The developed RNA aptamer intramer effectively inhibits TCF/beta-catenin transcriptional activity and target gene expression.
• This RNA intramer demonstrates significant anti-cancer effects on colon cancer cells, reducing their growth and tumorigenicity.
• RNA intramers represent a potential gene therapeutic strategy for TCF/beta-catenin-mediated carcinogenesis.