PDPN and small cell lung carcinoma: We co-cultured mRFP-labeled SCLC cell lines (NCI-H82 and NCI-H69) with Venus-labeled CAFs expressing WT-PDPN (CAFs-PDPN) or CAFs-Control (CAFs-Ctrl); after 4 days, we then counted the number of viable NCI-H82 cells.