High expression of ABL2 promotes gastric cancer cells migration, invasion and proliferation via the TGF-β and YAP signaling pathways

Background: The Abelson-Related Gene (ABL2) is expressed in various malignancies. However, its role in gastric cancer (GC) regarding tumor proliferation, metastasis, and invasion remains unclear. Methods: ABL2 expression in clinical specimens was assessed using quantitative real-time fluorescence PCR (qRT-PCR). Western blotting and immunofluorescence assay determined protein levels. Additionally, Transwell migration and invasion, cell counting kit-8 (CCK-8) and colony-formation assays analyzed the effect of ABL2 on GC cells. Protein levels related to GC cells were assessed through Western blotting. The effects of si-ABL2 combined with GA-017 that activated YAP on cell migration, invasion and proliferation were investigated. Results: ABL2 expression was upregulated in human GC tissues compared to paracancer tissues, and it was positively related to tumor node metastasis classification (TNM) stage. Furthermore, high ABL2 levels promoted the proliferation, metastasis, and invasion capacity in GC cells. Elevated ABL2 expression enhanced the expression of MMP2, MMP9, and PCNA while decreasing TIMP1 and TIMP2 expression. It also increased the p-SMAD2/3 expression and YAP expression, decreased the expression of p-YAP in GC cells. Furthermore, GA-017 increased ABL2 expression in MGC-803 cells and counteracted the effects of si-ABL2 on cell migration, invasion and proliferation. Conclusion: These findings indicated that heightened ABL2 expression could activate TGF-beta/SMAD2/3 and YAP signaling pathway, promoting epithelial mesenchymal transformation (EMT), and enhancing multiplication, metastasis, and invasion in GC cells.