Taken together, our results suggest that TSPX may suppress the development and/or progression of lung adenocarcinoma by downregulating AREG, BIRC3, DKK1, EREG, FOSL1, MYC, and PLAU, which could exacerbate lung adenocarcinoma, and upregulating the tumor suppressor CACNA2D2. This evidence concerns the gene DKK1 and lung adenocarcinoma.