MACC1 overexpression in carcinomaassociated fibroblasts induces the invasion of lung adenocarcinoma cells via paracrine signaling

Carcinomaassociated fibroblasts (CAFs) are essential for initiating lung cancer cell invasion and metastasis. An elevated MACC1 expression has been implicated in the progression of lung adenocarcinoma. Hitherto, the role of MACC1 in lung adenocarcinomaderived CAFs remains unclear. In this study, CAFs isolated from the tissues of patients with lung adenocarcinoma expressed typical CAF markers (shown by immunohistochemical and immunofluorescence analysis) and exhibited enhanced migration and invasion abilities when cocultured with A549 cells in a microfluidic model. MACC1overexpressing CAFs not only demonstrated an increased invasion, but also exerted a promoting effect on the invasion of tumor cells. The reduced expression of MACC1 impaired the invasive ability of the CAFs. Western blot analysis and RTqPCR analysis demonstrated that multiple paracrine pathways were activated in the MACC1overexpressing CAFs. Overall, this study presents a novel role of MACC1 in CAFinduced lung adenocarcinoma cell invasion, which possibly occurs via paracrine signaling. Furthermore, MACC1 was indicated to be a potential therapeutic target for lung adenocarcinoma.