Gene expression profile at single cell level of cells from whole lung to assess MAGE-A4 expressing tumor alterations in tumor microenvironment

Melanoma Antigen-A4 (MAGE-A4) is a common cancer testis antigen expressed in human non-small cell lung cancer; however, whether and how it contributes to cancer initiation and progression has remained less clear. We engineered mice to express human MAGE-A4 specifically in Club cells of the bronchial epithelium, with or without loss of Pten in the same cells, to investigate the role of MAGE-A4 in tumor initiation and development. We used single cell transcriptomics and flow cytometry to evaluate the immune and other cells in the lung/lung tumor microenvironment that were altered in response to this cancer testis antigen. We found that endothelial cells in MAGE-A4 expression models upregulate CXCL12, which likely contributes to the increased plasma cell recruitment to the lungs infiltrating MAGE-A4-expressing lung tumors in both mouse and human. Single cells were isolated from whole lung of mice at 5 months of age when tumor had developed in MAG4/Pt lungs and were analyzed using scRNA-seq. Single cells were isolated from whole-lung from 4 genotypes of mice: CCSPWT MAGE-A4LSL Ptf/f (Cre-MAG4/Pt (wild-type)), CCSPiCre Ptf/f (Pt), CCSPiCre MAGE-A4LSL (MAG4), CCSPiCre MAGE-A4LSL Ptf/f (MAG4/Pt) and analyzed using scRNA-seq.