Communication of tumor-immune cells in 3d bioprinted lymph node environment

Melanoma is a very aggressive type of skin cancer that develops when melanocytes undergo malignant transformation. The aim of this thesis is to examine how gold nanoparticles (AuNPs), the mTOR inhibitor temsirolimus, and selected phytochemicals affect human A375 melanoma cells, with a particular focus on how immune cell-tumor communication shapes treatment outcomes. Experiments are carried out in both standard 2D cultures and advanced 3D models, including hydrogels and bioprinted scaffolds, to better reflect the complex tumor microenvironment. The 3D systems incorporated extracellular matrix (ECM)-like materials and, in some cases, THP-1-derived M0 macrophages to simulate the immune component of tumors. In 2D monoculture systems, A375-GFP cells seem more vulnerable to AuNP treatment, most likely due in part to fluorescence quenching, while A375-WT tolerates higher doses of AuNPs in both 2D and 3D systems. Temsirolimus shows a more potent effect in 3D than in 2D cultures, though its effects are delayed, reflecting the slower penetration and altered uptake in ECM-rich conditions. The combination of AuNP and temsirolimus reduces A375-WT viability more than either single treatment, acting synergistically. Curcumin induces viability reduction in both 2D and 3D rapidly, which can be linked to inhibition of NK-kB, PI3K/Akt, and MAPK pathways. The other phytochemicals (EGCG, botulin, thymoquinone) cause dose- and time-dependent cell death. Stronger effects are shown when delivered with AuNPs, likely driven by elevated ROS and loss of mitochondrial membrane potential. On the other hand, M0 macrophages responded differently to treatments. AuNPs alone are well-tolerated, but high-dose temsirolimus (500 nM) and curcumin (40 uM) reduced their viability, especially after bioprinting, which creates mechanical stress. Co-culture experiments revealed that the presence of macrophages could alter drug responses mainly by accelerating but sometimes slowing cell death, underscoring the importance of cell-cell interactions. By integrating these in vitro findings with physiologically-based pharmacokinetic (PBPK) modeling of curcumin, this work bridges experimental results with potential in vivo outcomes. Overall, the study highlights the value of combining immune-tumor cocultures with 3D bioprinted models for more predictive drug testing and points toward the promise of nano-particle-drug-phytochemical combinations in melanoma therapy.