Bulk RNA-Seq gene expression data for 289 primary and metastatic pancreatic ductal adenocarcinoma (PDAC) tumor samples from FFPE blocks.

Pancreatic Ductal Adenocarcinoma (PDAC) is a deadly disease with a 5 year overall survival rate of 11%. In order to better understand and characterized PDAC we have performed RNAseq on 289 primary and metastatic PDAC tumors collected at our center. Nucleic acids (RNA and DNA) were extracted from formalin fixed paraffin embeded FFPE tumor tissue with tumor enriched regions identified by pathologic analysis. RNA sequencing and resulting gene expression data was then used to study biologic differences in primary PDAC tumors that metastasized to either the liver or to the lung but not liver based on clinical data review. A novel gene expression signature was identified for liver vs lung avid metastatic properties. Samples in the entire cohort were then scored based on this gene signature. Pathway analysis revealed that samples high for this signature (as well as liver cohort patient samples) were enriched for pathways involved in ongoing replication stress response, and this was associated with poorer patient outcome. Primary and metastatic PDAC samples obtained from our center that were formalin fixed and paraffin embedded were pathologically reviewed and regions of high tumor content were scraped from slides for nucleic acid extraction and RNA seuencing. The pathologic review was performed at OHSU and at Tempus, where the extraction and sequencing was performed. Raw sequencing data was returned to OHSU where it was pseudoaligned with kallisto ***Raw data have been deposited in dbGaP (phs003597.v1.p1)***