Differentiation Treatment Applied to Lung Cancer Model Reduces Pathogenic Traits in Vitro

Non-small cell lung cancer (NSCLC) relapse after therapy is linked to the high aggressiveness, chemoresistance and metastatic potential of tumor cells due, in part, to the presence of cancer stem cells (CSCs). Pro-differentiation approaches have shown promising results for leukemia and in some solid cancer models, offering a possibility to enhance current anti-cancer therapies. Here, the human NSCLC line A549 is exposed to a serum-containing medium supplemented with pro-differentiation factors (DM), and effects on the cells' proliferation, migration and adhesion properties are assessed in vitro, alongside CSC marker expression analyzed after treatment in 2D or 3D culture conditions. A549 cells exposed to DM exhibited notable morphological changes, with significant increase in cellular footprint and vesicle accumulation. These phenotypic alterations coincided with significant inhibition of proliferation and migration, whereas adhesion properties increased, similar to alkaline phosphatase activity. DM treatment of A549 cells also caused a significant reduction in clonogenic ability by two thirds, as well as halving anchorage-independent colony formation and spheroid growth, alongside a reduced expression of stemness markers SOX2, NANOG, CD44 and ABCG2, and of ALDH activity and aquaporin function. These results indicate decreased pathogenic features of NSCLC cells after DM exposure, suggesting that pro-differentiation treatment may represent a valuable option for further preclinical testing.