Abstract LB-B10: Transcriptional Landscape in the Human Knock-in Isogenic Line for P53 Polymorphism Codon 72

Background: Codon 72, the most representative polymorphism of p53, commonly encodes the two kinds of amino acids, proline (P) or arginine (R), which is interestingly located within proline-rich domain to regulate p53-dependent transactivation. Although the previous reports have compared the polymorphism-mediated p53 transactivation, the results have some limitations that have been mined artificially on abnormal cells or plasmid-based expression. Thus, overcoming the concerns, we here established the isogenic lines to identify codon 72 polymorphic-dependent p53 transactivation. Experimental design: We established isogenic line based on human induced pluripotent stem cells (hiPSC) with either the proline or arginine at codon 72 of p53 (P and R-type p53), using BAC-mediated homologous recombination system. In addition, to set the baseline mRNA expression level of p53 target genes, p53-null hiPSC has been generated with simultaneous reprogramming-CRISPR system. We applied RNA-sequencing technology to profile transcription patterns between three cell lines, p53-P, p53-R, and p53-null hiPSCs, under genotoxic stress, Doxorubicin treatment. Results: Molecular signature analysis shows the significant difference of transcriptional patterns in PI3K-Akt signaling pathway, focal adhesion, cell-cell adhesion and Wnt signaling pathway by KEGG pathway mapping between P- and R-type. We identified both PI3K-Akt signaling related genes and focal adhesion related genes increased in P-type p53 than R-type p53, but expression patterns are similar with p53-null cell in focal adhesion. On the other hand, cell-cell adhesion related gene patterns down regulated comparing with p53-null cell. Lastly, R-type p53 gene expression shows the most increased pattern than other two cell types. Conclusions: The isogenic line-based p53 polymorphism study reveals the differences intrinsically in the p53 polymorphism dependent-cell survival signaling, PI3K-Akt signaling pathway. Acknowledgements: This work was supported by Korea Institute of Oriental Medicine Grant K17131 and National Research Foundation of Korea Grants 2013M3A9B4076487. Citation Format: Seo-Young Lee, Sun-Ku Chung, Jung-Hyun Park, Soo A Oh, Kyoung-Jae Won. Transcriptional landscape in the human Knock-in isogenic line for p53 polymorphism codon 72 [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr LB-B10.