ITGA3 interacts with VASP to regulate stemness and epithelial-mesenchymal transition of breast cancer cells

The interaction of integrin and extracellular matrix (ECM) has a profound implication on pathological conditions such as tumor growth and infiltration. Related reports have confirmed that integrin α3 (ITGA3) influences the development of bladder cancer, head and neck cancer, colorectal cancer and other cancers. However, the mechanism of ITGA3 in breast cancer is unknown.

The impact of ITGA3 on the biological features of breast cancer cells was explored using the Transwell and wound healing assays. In addition, its influence on stemness of breast cancer cells was examined with the sphere formation assay. The possible mechanism by which ITGA3 regulates breast cancer was explored using Western blot. The interaction between ITGA3 and VASP was determined by co-immunoprecipitation and immunofluorescence staining assays.

Results show that downregulation of ITGA3 promotes breast cancer cell proliferation, apoptosis, invasion and migration. Indeed, suppression of ITGA3 negatively regulates the stemness of breast cancer cells and EMT process. Our findings indicate that ITGA3 interacts with VASP and regulates its expression, and knockdown of ITGA3 inhibits the activity of the PI3K-AKT axis.

Our results show that ITGA3-VASP modulates breast cancer cell stemness, EMT and PI3K-AKT pathways. Therefore, ITGA3 might be a druggable target for clinical breast cancer management.