Proteogenomic Network Analysis of Context-Specific KRAS Signaling In Mouse-to-Human Cross-Species Translation

The highest frequencies of KRAS mutations occur in colorectal carcinoma (CRC) and pancreatic ductal adenocarcinoma (PDAC). Therapeutically targeting downstream pathways mediating oncogenic properties of KRAS mutant cancers is limited by an incomplete understanding of the contextual cues modulating the signaling output of activated KRAS. We performed mass spectrometry on mouse tissues expressing wild-type or mutant KRAS to determine how tissue context and genetic background modulate oncogenic signaling. Mutant KRAS dramatically altered the proteomes and phosphoproteomes of pre-neoplastic and neoplastic colons and pancreases in a largely context-specific manner. We developed an approach to humanize the mouse networks with data from human cancer and identified genes within the CRC and PDAC networks synthetically lethal with mutant KRAS. Our studies demonstrate the context-dependent plasticity of oncogenic signaling, identify non-canonical mediators of KRAS oncogenicity within the KRAS-regulated signaling network, and demonstrate how statistical integration of mouse and human datasets can reveal cross-species therapeutic insights.