PROJECT SUMMARY The human kinome is one of the most established family of druggable proteins. Yet out of more than 600 kinases only a fraction is currently the focus of clinical studies and chemical probe development, and many kinases remain understudied. Kinase inhibitors play an important role in the treatment of human cancers, such as advanced renal cell carcinoma (RCC), a malignancy whose incidence is increasing and carries a poor prognosis. While RCC clinical outcomes are improving with tyrosine kinase inhibitors and immunotherapies, the majority of patients ultimately succumb to progressive, resistant disease. Our long-term goal is to find cures for advanced RCC by identifying and validating novel RCC kinase targets for drug development. PNCK is an understudied kinase. Analyzing the Illuminating the Druggable Genome (IDG) Knowledge Portal Pharos along with other resources revealed that PNCK is the most differentially overexpressed kinase in RCC patients and is associated with worse disease specific survival. In our preliminary studies PNCK overexpression led to significant increase in RCC cell growth and proliferation, while PNCK inhibition exerted direct antitumor effects, by inhibition of cell growth, induction of RCC cell cycle arrest and apoptosis, as well as indirect effects, by regulating expression of angiogenesis and DNA damage response pathways. These findings highlight the clinical and biological relevance of PNCK in RCC. The objective of this proposal is to generate and then integrate systems level signatures of PNCK in RCC with target-based kinase profiling of PNCK small molecule inhibitors to inform future chemical probe and drug lead optimization programs via two Specific Aims. Aim 1 will generate transcriptomics and active kinome signatures from PNCK overexpression and knockdown cell lines and identify PNCK-driven pathways and signaling networks by multi-omics analysis. Aim 2 will optimize and then characterize our current PNCK inhibitors using computational models and NanoBRET target engagement followed by kinase profiling to assess selectivity and off targets. Combined, the systems level signatures of PNCK in RCC and target-based kinase profiles of the best compounds will further elucidate the biology and therapeutic potential of PNCK in RCC and inform subsequent chemical probe and drug lead optimization projects. Our team combines complementary expertise in computational systems pharmacology / drug discovery (Schürer), translational kidney cancer research (Merchan), and multi-omics (including chemical proteomics MIB/MS) functional characterization of the cancer kinome (Johnson) to successfully complete the proposed project Aims.