Lung primary cultures were also found to be devoid of epithelial and endothelial cells as revealed by negative immunostaining for pancytokeratin and CD31, respectively and did not express cancer associated fibroblasts (CAF) markers such as desmin, fibroblast activated protein α and PDGF receptor β (data not shown) confirming the lack of cancer impact. The gene discussed is PECAM1; the disease is cancer.