This study aims to investigate the mechanism by which astragalus polysaccharides (APS) regulate carcinoembryonic antigen-related cell adhesion molecule 7 (CEACAM7) and via the epithelial-mesenchymal transition (EMT) pathway to inhibit the malignant biological behavior of lung cancer A549 cells.

The effects of APS on A549 cell proliferation were assessed using the CCK-8 assay. The induction of apoptosis by APS was evaluated using flow cytometry. The impact of APS on cell invasion and migration was assessed using Transwell assays and wound healing assays. Western blot analysis was performed to detect the expression levels of CEACAM7 and EMT-related markers.

The CCK-8 results showed that compared with the control group (2.1±0.17), the OD450 values of 100 mg/L, 200 mg/L and 400 mg/L in the APS treatment group were (1.63±0.12), (1.38±0.11) and (1.09±0.09) respectively on the fourth day. CCK-8 showed that APS inhibited the proliferation and promoted apoptosis of A549 cells in a dose-dependent manner. The high dose group (400 mg/L) showed the most significant inhibition. Flow cytometry showed APS treatment group significantly promoted the apoptosis of A549 cells, and the apoptotic effect was dose-dependent. Compared with the control group, the APS treatment groups (100 mg/L, 200 mg/L, and 400 mg/L) significantly enhanced A549 cell apoptosis with a dose-dependent effect, compared with the control group (16.21±1.32%), the apoptosis rates in 100 mg/L, 200 mg/L and 400 mg/L treatment groups were (26.5±2.32%), (33.7±3.11%) and (39.4±3.6%), respectively. The apoptosis rate in the high dose group was higher than that in the control group (P<0.05). Compared with the cell number of the control group (76.32±6.32), the cell number of APS treatment group at 100 mg/L, 200 mg/L and 400 mg/L was (57.32±4.16), (38.13±2.67) and (25.30±1.96) respectively. Compared with the scratch healing rate of the control group (69.81±5.16)%, the healing rate of 100 mg/L, 200 mg/L and 400 mg/L in APS treatment group was(57.95±4.66)%, (49.72±4.24)% and (41.56±3.38)% respectively.

Astragalus polysaccharides inhibit the proliferation, invasion, and migration of lung cancer A549 cells by regulating CEACAM7 via the EMT pathway. This study provides a theoretical basis for the development of new lung cancer treatment strategies based on natural drugs.