SPINT1 and lung adenocarcinoma: Highly invasive CL1-5 lung cancer cells were established and derived from the in situ lung adenocarcinoma cells (CL1-0) after 5-time isolations of invasive cells using Matrigel-coated transwell assays.40 We found that highly invasive CL1-5 cells expressed a low HAI-2 level compared to lowly invasive CL1-0 cells, while both cells lacked HAI-1 expression (Fig. 1b).