Interestingly, in the presence of HCC-Gelatin hydrogels, but in absence of physical constraints, i.e. distant walls, no apical-basal polarization of the cells was observed, as shown by staining for multidrug resistance-associated protein 2 (MRP2) and zonula occludens-1 (ZO-1) (Fig. 5b). The gene discussed is TJP1; the disease is hepatocellular carcinoma.