Upregulation of E-cadherin in bronchoalveolar lavage fluid-derived exosomes in patients with lung cancer

Background: Lung cancer features extremely high rates of morbidity and mortality. Bronchoalveolar lavage fluid (BALF), obtained by bronchoscopy and bronchoalveolar perfusion, can provide information on the cellular components of the lung microenvironment to assist with diagnosis and treatment of lung cancer.

Methods: BALF was performed using a flexible bronchofiberscope. Exosomes were collected by ultracentrifugation. ELISA detected the amount of E-cadherin. Transmission electron microscopic, ELISA and WB were conducted to identify the existence of the exosomes. Transwell and Wound healing assays were used to detect the ability of migration and invasion.

Results: We identified the existence of exosomes in BALF. Furthermore, we observed larger amounts of E-cadherin in the BALF obtained from patients with lung cancer than in the control obtained from the healthy side of pneumonia. Exosomes from lung cancer groups promoted the migration and invasion of A549 cancer cells.

Conclusion: The exosomes from lung cancer BALF promoted the migration and invasion of A549 cancer cells by carrying E-cadherin. E-cadherin on the surface of exosomes may act through a VE-cadherin dependent mechanism and induce lung cancer metastasis.