SPON2 and lung adenocarcinoma: We studied the expression characteristics and biological function of SPON2 in lung adenocarcinoma, and confirmed that SPON2 is an extracellular matrix protein secreted by CAFs with high specific expression and promoting the invasion and metastasis of lung adenocarcinoma, and its expression level is significantly positively correlated with the degree of migration and invasion; SPON2 can enhance the promotion of CAFs on the invasion and progression of lung adenocarcinoma cells.