A Robust siRNA Screening Approach with Optimized Conditions for Large-Scale Transfection in Multiple Human Cancer...

Area of Science:

• Molecular Biology
• Genomics
• Cancer Research

Background:

• RNA interference (RNAi) is crucial for gene function exploration and target identification in drug discovery.
• Small interfering RNA (siRNA) phenotypic screening is a common strategy, particularly in oncology.

Purpose of the Study:

• To develop and validate a large-scale automated siRNA transfection and cell phenotypic screening method.
• To utilize colony formation as a sensitive readout for identifying genes essential for cell viability and proliferation.

Main Methods:

• Optimized liposomal reagents for efficient and non-toxic siRNA transfection across various cell lines.
• Pre-screened and pooled the most active and specific siRNA oligonucleotides against each target gene.
• Assessed colony formation after 7-14 days in 96-well plates following low-density cell seeding.

Main Results:

• The colony formation assay demonstrated higher sensitivity than standard proliferation assays for detecting long-term effects and slow-growing cell phenotypes.
• Combining multiple siRNA oligonucleotides per target mitigated off-target toxic effects, yielding robust and reliable results.
• Parallel screening across multiple cancer cell lines identified target-related genetic dependencies in diverse tumor models.

Conclusions:

• The developed automated method provides a sensitive and reliable platform for large-scale gene function and target validation in cancer research.
• This approach facilitates the identification of novel therapeutic targets by revealing essential genes and genetic dependencies across various cancer types.