Advancing osteosarcoma 3D modeling in vitro for novel tumor microenvironment-targeted therapies development
Sofia Almeida Costa, João Rodrigues, Carolina Vieira, Sofia Dias, Juliana Santos Rosa Viegas, Flávia Castro, Bruno Sarmento, Catarina Leite Pereira
Abstract
Osteosarcoma (OS) represents one of the most common primary bone cancers affecting children and young adults. The available treatments have remained unimproved for the past decades, hampered by the poor knowledge of OS etiology/pathophysiology and the lack of innovative, predictive and biologically relevant in vitro models, that can recapitulate the 3D OS tumor microenvironment (TME). Here, we report the development and characterization of an innovative 3D model of OS, composed of OS tumor cells, immune cells (macrophages) and mesenchymal stem cells (MSCs), that formed a multicellular tissue spheroid (MCTS). This fully humanized 3D model was shown to accurately mimic the native histological features of OS, while innately leading to the polarization of macrophages towards an M2-like phenotype, highly aggressive and pro-tumor profile. Upon the exposure to immunomodulatory molecules, the MCTS were shown to be responsive by shifting macrophages polarization, and dramatically altering the TME secretome. In agreement, when treated with immunomodulatory/stimulatory nanoparticles (NPSs), we were able to revert the TME secretome towards an anti-inflammatory profile. This study establishes an advanced 3D OS model capable of shedding light on macrophages and MSCs contributions to disease progression, paving the way for the development of innovative therapeutic approaches targeting the OS TME, while providing a biologically relevant in vitro tool for the efficacy screening of novel OS therapeutic approaches. • Generated Heterotypic OS MCTS can recapitulate the described extracellular matrix (ECM) of OS native tumor. • OS MCTS innately generated tumor microenvironment (TME) leads to M2-like polarized tumor, resembling OS aggressiveness. • The heterotypic nature of OS MCTS suggests a metabolic shifts in vitro , through an increased amount of lipid droplets. • OS MCTS are responsive to external immunomodulatory stimulus by shifting cell polarization, and its secretome. • Immunomodulatory MDP-loaded NPs can modulate OS TME towards an anti-tumoral profile.