Figure 1: 2D and 3D cellular culture systems. In the 2D system, cells adhere to the plastic, and are visualized usually as monolayers attached to the cell culture plate surface (1A). In the 3D system, cells are structured as a sphere, which commonly grows in suspension in the medium. There are three different regions in these spheroids: necrotic (1), quiescent (2) and proliferating (3) zones (1B). Ultra-Low Attachment plates or Matrigel-coated plates are usually used for 3D cell culture

Figure 2: Oxidative stress in the liver microenvironment. Cell types such as sinusoidal hepatic cells, HSC and KC are sensitive to oxidative stress. In the space of Disse, this triggers HSC activation, stimulating peroxidation of lipids with consequent collagen synthesis and proliferation. In the sinusoidal space, oxidative stress results in release of cytokines which induce inflammation and apoptosis. In addition, some immune cells which are part of the liver microenvironment, such as B and T lymphocytes, NK cells and macrophages, are also damaged by oxidative stress

Figure 3: Mesenchymal stem cell role in liver cancer. BMMSC can migrate to the tumor site and interact with other MSC or producing factors into the site. This tumor microenvironment is characterized by the presence of carcinogenic stem cells, cytokines and Kupffer cells, which are essential to promote tumor development and growth