PROJECT SUMMARY This is an application for a Research Supplement to Promote Diversity in Health-Related Research (PA-20-222). The parent R01 project associated with this application is entitled “Lineage Heterogeneity and Plasticity in Lung Cancer” supported by NCI (5R01CA240342 -02). Douglas Mansell is the diversity candidate. He is a US citizen of African-American descent and is currently a postdoctoral fellow at Icahn School of Medicine at Mount Sinai, New York. The main goal of this study is to characterize the significance of one of our lead candidates PBX1 defining the lineage state of a novel subset of lung adenocarcinoma. We will test the subclass-specific local chromatin structure and then investigate the roles of novel lineage transcription factors specifically enriched in the subgroup of lung adenocarcinoma, whether they are essential for maintaining the cellular state of lung cancer cells and are dependent on the committed lineage for their survival.