Derepression of co-silenced tumor suppressor genes by nanoparticle-loaded circular ssDNA reduces tumor malignancy

Area of Science:

• Oncology
• Molecular Biology
• Biotechnology

Background:

• Co-silencing of multiple tumor suppressor genes contributes to cancer progression.
• Current anticancer therapies targeting single genes have limited efficacy.
• MicroRNAs (miRNAs) are key regulators that can silence tumor suppressor genes.

Purpose of the Study:

• To develop small circular single-stranded DNA (CSSD) as a therapeutic strategy to up-regulate co-silenced tumor suppressor genes.
• To investigate the therapeutic potential of CSSDs in inhibiting cancer proliferation, metastasis, and promoting apoptosis.
• To evaluate the efficacy and stability of CSSDs compared to existing miRNA inhibitors.

Main Methods:

• Development of CSSDs designed to sequester specific miRNAs.
• Transfection of CSSDs into cancer cells and assessment of tumor suppressor gene expression.
• In vitro, ex vivo, and patient-derived xenograft models were used to evaluate therapeutic effects.
• Nanoparticle-mediated delivery of CSSDs was employed to enhance transfection efficiency.

Main Results:

• Low expression of tumor suppressor genes KLF17, CDH1, and LASS2 correlated with shortened survival in cancer patients.
• CSSD-9 transfection successfully up-regulated KLF17, CDH1, and LASS2 expression.
• CSSD treatment inhibited tumor proliferation and metastasis, and promoted apoptosis in various cancer models.
• CSSDs demonstrated superior stability and efficacy compared to conventional miRNA inhibitors.
• Nanoparticle delivery significantly improved CSSD transfection efficiency.

Conclusions:

• CSSDs represent a promising therapeutic strategy for targeting the co-silencing of multiple tumor suppressor genes in cancer.
• This approach offers a potential new avenue for developing more effective anticancer therapies.
• CSSDs can be utilized as therapeutic miRNA inhibitors to combat cancer malignancy.