Abstract 2690: Massively parallel multiplexed methods to screen hundreds of barcoded cancer cell line models with small molecules or genetic perturbations using next-generation sequencing
Authors: Bender Samantha , Zhu Cong , Wang Li , Rothberg Michael , Dempster Joshua , Paolella Brenton , Kocak Mustafa , Laird Massami , Rossen Jordan , Stumbraite Karolina , Bryan Jordan , Wang Vickie , Doench John , Vazquez Francisca , Tsherniak Aviad , Golub Todd , Roth Jennifer 
Published: August 2019

Abstract
Phenotypic screening is a valuable tool to identify compounds to treat cancer, but is limited as it is time and resource intensive to screen hundreds of cancer cell lines. In order to increase the throughput of phenotypic screening, we set out to expand and further develop the PRISM method (Profiling Relative Inhibition Simultaneously in Mixtures) [Yu et al., 2016]. PRISM is a method to barcode cell lines with a unique 24 nucleotide barcode and mix them together to screen simultaneously in a pool, decreasing the time and cost of screening. The previously described PRISM method was limited in that it used only 100 adherent cell lines of one cancer model context, it required the use of a highly specialized Luminex bead-based detection system, and it was only applicable to small molecule screening.
Here we report on the expansion of our barcoded cell line collection to 800 cancer cell lines of over 45 lineages, an improved method called PRISMseq using next-generation sequencing, and a novel method to perform genetic perturbations in 500 cancer cell lines simultaneously called PRISPR (PRISM/CRISPR). PRISMseq allows for assaying compound cell line sensitivity profiles in a large pool of hundreds of cell lines and detecting the DNA barcodes using next-generation sequencing (NGS). We recapitulate the known biology for established oncology drugs like the BRAF, EGFR, BCR-ABL and MDM2 inhibitor classes using this method with our cell line panel. We also further extended this method to be applicable to genetic perturbation using CRISPR/Cas9 knockout of individual genes concurrently in hundreds of cancer cell lines. We are able to recover expected biomarkers or genetic dependencies for our CRISPR/Cas9 validation reagents.
This expanded PRISM profiling approach increases statistical power due to the addition of cancer contexts in our cell line collection, and improves versatility by enabling the screening of both small molecules and genetic perturbations. We believe that this method has overcome the limitations of the original PRISM method. It has also overcome the limitations of phenotypic screening, as the resources required to screen hundreds of cell lines has been decreased by orders of magnitude.
Citation Format: Samantha Bender, Cong Zhu, Li Wang, Michael Rothberg, Joshua Dempster, Brenton Paolella, Mustafa Kocak, Massami Laird, Jordan Rossen, Karolina Stumbraite, Jordan Bryan, Vickie Wang, John Doench, Francisca Vazquez, Aviad Tsherniak, Todd Golub, Jennifer Roth. Massively parallel multiplexed methods to screen hundreds of barcoded cancer cell line models with small molecules or genetic perturbations using next-generation sequencing [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2690.