Project 1 Project Summary/Abstract Human lung tumors are metabolically distinct from adjacent lung tissue. It is unknown whether these reprogrammed activities predict clinical outcomes or represent meaningful therapeutic liabilities. The major bottleneck in understanding the clinical relevance of cancer metabolism has been a lack of data about human tumor metabolism in vivo. For the first time, we have overcome this limitation and used intra-operative infusions with 13C-glucose to define metabolic phenotypes in human non-small cell lung cancer (NSCLC). We reported that one NSCLC subset displays prominent import of lactate, while another subset produces lactate from glucose. Our observation that lactate uptake via monocarboxylate transport protein-1 (MCT1) correlates with rapid disease progression in lung adenocarcinoma is the first and to date only metabolic flux phenotype demonstrated to predict clinical outcomes in any human cancer. In this Project, we will expand the scope of metabolic analysis in human NSCLC, performing 13C infusions in more than 100 patients, assessing hundreds of metabolites in each tumor, and following clinical histories to identify new activities correlating with outcomes. In Specific Aim 1, tumors infused with 13C will be analyzed by imaging, quantitative histopathology, RNA sequencing and whole exome sequencing to understand relationships between these features and cancer metabolism. We will focus on identifying metabolic features that correlate with reduced progression-free survival, under the rationale that such activities are attractive therapeutic targets to test in preclinical models. We will establish patient-derived xenografts (PDXs) from these tumors to test the importance of predictive metabolic activities for tumor growth and metastasis. While our open-ended metabolomics approach is designed to uncover novel therapeutic targets, based on our earlier work, we will specifically test whether inhibiting MCT1 reduces tumor growth and metastasis in mice. In Specific Aim 2 we will follow up on our observation that lung squamous cell carcinomas require lactate export for maximal growth. We will test whether genetic or pharmacological inhibition of novel molecular components of MCT4-mediated lactate export suppresses tumor growth in mouse models and PDXs. Specific Aim 3 will examine metabolic crosstalk among cancer cells and several important immune cell populations in the tumor microenvironment in mice and humans. We will test the hypothesis that lactate metabolism impacts these metabolic exchanges and that blocking lactate transport enhances the efficacy of immune checkpoint blockade therapy. Overall, these efforts will produce the most detailed and clinically- relevant view of NSCLC metabolism to date. The ability to combine our ongoing study assessing metabolic flux in human NSCLC with large legacy clinical datasets ideally positions us to understand the relationship between tumor metabolism and cancer progression,...