Signaling Heterogeneity in Small Cell Lung Cancer

Small cell lung cancer (SCLC) is among the most aggressive and deadly human cancers. It represents approximately 15% of all lung cancers, and it is responsible for over 30,000 deaths in the US and 200,000 deaths worldwide every year. SCLC responds to treatment but recurs frequently and aggressively, with the majority of patients dying within 12 months of diagnosis. No targeted therapies are yet available for SCLC. New strategies are needed to improve outcomes for patients with SCLC. This project will expand upon preliminary data identifying at least two distinct subpopulations of cells in SCLC cell lines and patient-derived xenografts comprising a neuroendocrine (NE) and mesenchymal-like (ML) set of cell line populations. Dr. Lehman and his team will use an innovative approach using mass cytometry, using rare earth antibody conjugates to antibody label more than 30 proteins simultaneously, including phospho and signaling proteins. This technique will establish at a single-cell resolution tumor heterogeneity and signaling in small cell lung carcinoma in multiple primary human samples as well as in patient-derived xenograft samples before and after chemotherapy treatment. This proposal aims to (1) characterize the signaling of subpopulations in human primary SCLCs at a single-cell resolution, (2) identify changes in tumor heterogeneity and in these subpopulations after chemotherapy treatment and relapse, and (3) disrupt and manipulate developmental signaling/ associated subpopulations (prototypically the HH [Hedgehog] and Notch/DLL3 pathways) to reduce tumor burden and lead to targeted rational combination therapy for SCLC.