RNA-Seq-based toxicogenomic assessment of fresh frozen and formalin-fixed tissues yields similar mechanistic insights

Scott S. Auerbach, Dhiral P. Phadke, Deepak Mav, Stephanie Holmgren, Yuan Gao, Bin Xie, Joo Heon Shin, Ruchir R. Shah, B. Alex Merrick, Raymond R. Tice

Research output: Contribution to journalArticlepeer-review

15 Scopus citations


Formalin-fixed, paraffin-embedded (FFPE) pathology specimens represent a potentially vast resource for transcriptomic-based biomarker discovery. We present here a comparison of results from a whole transcriptome RNA-Seq analysis of RNA extracted from fresh frozen and FFPE livers. The samples were derived from rats exposed to aflatoxin B1 (AFB1) and a corresponding set of control animals. Principal components analysis indicated that samples were separated in the two groups representing presence or absence of chemical exposure, both in fresh frozen and FFPE sample types. Sixty-five percent of the differentially expressed transcripts (AFB1 vs. controls) in fresh frozen samples were also differentially expressed in FFPE samples (overlap significance: P<0.0001). Genomic signature and gene set analysis of AFB1 differentially expressed transcript lists indicated highly similar results between fresh frozen and FFPE at the level of chemogenomic signatures (i.e., single chemical/dose/duration elicited transcriptomic signatures), mechanistic and pathology signatures, biological processes, canonical pathways and transcription factor networks. Overall, our results suggest that similar hypotheses about the biological mechanism of toxicity would be formulated from fresh frozen and FFPE samples. These results indicate that phenotypically anchored archival specimens represent a potentially informative resource for signature-based biomarker discovery and mechanistic characterization of toxicity.

Original languageEnglish (US)
Pages (from-to)766-780
Number of pages15
JournalJournal of Applied Toxicology
Issue number7
StatePublished - Jul 1 2015
Externally publishedYes


  • Aflatoxin B1
  • FFPE
  • Mechanism
  • RNA-Seq
  • Toxicogenomics

ASJC Scopus subject areas

  • Toxicology


Dive into the research topics of 'RNA-Seq-based toxicogenomic assessment of fresh frozen and formalin-fixed tissues yields similar mechanistic insights'. Together they form a unique fingerprint.

Cite this