Refined molecular taxonomy and treatment remodeling of pancreatic cancer using single-cell resolution

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal and treatment-refractory cancer. Molecular stratification in pancreatic cancer remains rudimentary and does not yet inform clinical management or therapeutic development. Here we construct a high-resolution molecular landscape of the multicellular subtypes and spatial communities that compose PAC using single-nucleus RNA-seq and whole-transcriptome digital spatial profiling (SP) of 43 primary PDAC tumor specimens that either received neoadjuvant therapy or were treatment-naïve. We uncovered expression programs across malignant cells and fibroblasts, including a newly-identified neural-like progenitor malignant cell program that was enriched after chemotherapy and radiotherapy and associated with poor prognosis in independent cohorts. Integrating spatial and cellular profiles revealed three multicellular communities: classical, squamoid-basaloid, and treatment-enriched. Our refined molecular and cellular taxonomy can advance precision oncology in PAC through stratification in clinical trials and as roadmap for therapeutic targeting of specific cellular phenotypes and multicellular interactions. Overall design: 18 specimens received no treatment prior to resection; 25 specimens received neoadjuvant chemoradiation therapy (e.g. CRT = FOLFIRINOX), losartan (L), and/or nivolumab (N) prior to resection; 2 specimens were non-malignant