Lung Adenocarcinoma Cells Respond Differently to Mechanical Stress in 3D Versus 2D Environments

The tumour microenvironment is influenced by mechanical stress, including shear and stretch forces, which regulate cancer cell behaviour. Although two-dimensional (2D) culture models are commonly used in cancer research, they fail to recapitulate complex mechanical cues of native tissues. In this study, we developed an ex vivo three-dimensional (3D) lung cancer model by seeding human lung adenocarcinoma cells into decellularised rat lungs and culturing them in a bioreactor mimicking respiratory motion and blood flow. Comparative analysis between 2D and 3D cultures, with and without simulated respiratory motion, revealed striking differences in cellular behaviour and gene expression. In 3D culture, respiratory motion enhanced cell adhesion, proliferation, and nuclear translocation of β-catenin and YAP, along with upregulation of integrin β1, E-cadherin, and genes related to extracellular matrix and cytokine signalling. In contrast, respiratory motion in 2D culture suppressed proliferation and induced apoptosis, highlighting the importance of extracellular matrix-mediated mechanotransduction. Our findings demonstrate that dimensionality and mechanical stress synergistically affect lung cancer cell dynamics and underscore the need for physiologically relevant 3D models incorporating mechanical cues for accurate cancer research.