Abstract 5054: Optimization and evaluation of an FFPE dual extraction protocol for next-generation sequencing applications

Abstract

Abstract Formalin-fixed paraffin-embedded (FFPE) biopsies are highly valuable and widely used tissue specimens for clinical diagnostics. However, obtaining sufficient and high-quality nucleic acid material from limited FFPE samples presents a challenge for downstream molecular analysis, such as next-generation sequencing (NGS). We present an optimized sequential extraction method that generates high-quality DNA and RNA from a single set of input tissues that is automatable and operation-friendly. This workflow performs well with reduced FFPE tissue input and efficiently supports various high-throughput clinical NGS applications. The DNA/RNA yield, quality, purity, and impacts on NGS assay performances were on par or better than an existing validated comparator extraction method. With comparable FFPE input, the new method demonstrated a superior extraction performance with significantly higher yield, quality, and purity. For DNA, NGS libraries were made with two different library preparation methods: a TA-ligation-based method and a single-strand-based method, followed by hybrid capturing and sequencing. The DNA from the new extraction method demonstrated a superior library conversion rate and improved target enrichment uniformity with both chemistries. This provides the potential of reduced input requirements, allowing very limited tissue, such as fine needle aspirate or core needle biopsy, for clinical NGS testing. The sequencing results were highly concordant between the existing and new extraction methods when the extracted DNA was subjected to a validated comprehensive genomic profiling (CGP) clinical test, demonstrating the quality and robustness of the extraction. For RNA, NGS libraries were made following the validated CGP clinical test with hybrid capturing, and the results were comparable between the two extraction methods. In conclusion, an FFPE extraction method was optimized to allow more clinical biopsy samples to be tested with different NGS workflows, providing a better diagnostic value for patient care. Citation Format: Rebecca Hong, Jieying Chu, Steven Hsiao, Daniel Whang, Steven P. Rivera, Heng Xie, Jiannan Guo. Optimization and evaluation of an FFPE dual extraction protocol for next-generation sequencing applications [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5054.