RT Journal Article SR Electronic T1 Preclinical Screening of Splice-Switching Antisense Oligonucleotides in PDAC Organoids JF bioRxiv FD Cold Spring Harbor Laboratory SP 2023.03.31.535161 DO 10.1101/2023.03.31.535161 A1 Wan, Ledong A1 Kral, Alexander J. A1 Voss, Dillon A1 Krainer, Adrian R. YR 2023 UL http://biorxiv.org/content/early/2023/04/03/2023.03.31.535161.abstract AB Aberrant alternative splicing is emerging as a cancer hallmark and a potential therapeutic target. It is the result of dysregulated splicing factors or genetic alterations in splicing-regulatory cis-elements. Targeting individual altered splicing events associated with cancer-cell dependencies is a potential therapeutic strategy, but several technical limitations need to be addressed. Patient-derived organoids (PDOs) are a promising platform to recapitulate key aspects of disease states and to facilitate drug development for precision medicine. Here, we report an efficient antisense-oligonucleotide (ASO) transfection method to systematically evaluate and screen individual splicing events as therapeutic targets in pancreatic ductal adenocarcinoma (PDAC) organoids. This optimized delivery method allows fast and efficient screening of ASOs that reverse oncogenic alternative splicing. In combination with advancements in chemical modifications and ASO-delivery strategies, this method has the potential to accelerate the discovery of anti-tumor ASO drugs that target pathological alternative splicing.Competing Interest StatementThe authors have declared no competing interest.