CRTC1 and lung adenocarcinoma: It has been shown both in lung and esophageal cancer cell lines and lung adenocarcinoma biopsy samples a link between activation of the CRTC1 (CREB-regulated transcriptional coactivator 1) oncogene, inactivation of the tumor suppressor LKB1 (hepatic kinase B1), and the presence of glycosylated COX-2 in pulmonary adenocarcinoma.