Oncogene-dependent regulation of tumor cells via stromal reciprocal signalling

Cancer is a heterocellular disease composed of tumor cells and stromal cells. Although stromal cells are known to regulate cancer progression, oncogene-dependent signalling through heterocellular cancer systems remains poorly elucidated. Here, we describe KRASG12D-dependent ‘reciprocal’ signalling across tumor and stromal Pancreatic Ductal Adenocarcinoma (PDA) cells. Heterocellular multivariate phosphoproteomics demonstrates how an oncogenic cue (KRASG12D), a trans-cellular signal (SHH), and stromal cells drive a reciprocal response in tumor cells. KRASG12D-dependent reciprocal signalling regulates the tumor cell phosphoproteome, total proteome, and mitochondria activity via an IGFR1/AXL-AKT axis. The reciprocal KRASG12D signalling state requires a heterocellular context and is unreachable by cell-autonomous oncogenic KRAS alone. These findings provide evidence that oncogenic KRAS regulates tumor cells via heterocellular reciprocation. Overall design: Comparison between FACS resolved iKRAS cells (previously in co-culture with PSCs) pertubed with a SHH antibody