My long-term goal is to improve therapies for patients with gastric and esophageal cancer by defining and targeting the key molecular alterations of these tumors. My research focuses on understanding mechanisms of resistance to targeted therapies in gastroesophageal cancer. Specifically, I study the role of intratumoral genomic heterogeneity in gastroesophageal cancer and the challenges it poses to personalized targeted therapies. To overcome these challenges, I am piloting studies to genomically characterize circulating cell-free DNA as a means to more accurately select therapeutic strategies. In addition, I am using functional biology to understand the mechanisms of de novo resistance to ERBB2-directed therapies in gastroesophageal cancer and develop new combination therapeutic strategies.