siRNA-mediated down-regulation of survivin inhibits bladder cancer cell growth

Area of Science:

• Oncology
• Molecular Biology
• RNA Interference Therapeutics

Background:

• Survivin is overexpressed in many tumors, including bladder cancer (BCa), correlating with disease progression and prognosis.
• Targeting survivin is a promising strategy for cancer therapy.
• Understanding the efficacy of specific survivin inhibitors is crucial for BCa treatment development.

Purpose of the Study:

• To evaluate and compare the therapeutic efficacy of two survivin-specific small interfering RNA (siRNA) constructs, SVV284 and SVV094.
• To assess the impact of these siRNAs on the growth, cell cycle, apoptosis, and survivin expression in human BCa cell lines.

Main Methods:

• Utilized five human BCa cell lines (EJ28, 5637, J82, RT112, RT4).
• Transfected cells with siRNA constructs (SVV284 and SVV094).
• Assessed cell viability, cell cycle progression, apoptosis, mRNA and protein expression of survivin using cell counting, flow cytometry, real-time RT-PCR, and ELISA.

Main Results:

• SVV284 significantly reduced viability (up to 47%) in EJ28 and 5637 cell lines within 24-72 hours.
• SVV284 induced G2/M cell cycle arrest, apoptosis, and multinucleation in sensitive cell lines.
• SVV284 effectively down-regulated survivin mRNA (≥50%) and protein (up to 99%) in EJ28, 5637, and J82 cells, leading to prolonged duplication time.
• RT112 and RT4 cells showed resistance to SVV284's effects.
• SVV094 exhibited less potent effects compared to SVV284 across all tested cell lines.

Conclusions:

• Anti-survivin siRNA treatment, particularly with SVV284, shows potential as a targeted therapy for BCa.
• SVV284 effectively inhibits BCa cell growth by targeting survivin, inducing cell cycle arrest and apoptosis.
• Differential sensitivity among BCa cell lines suggests patient stratification may be necessary for effective siRNA therapy.