Ink comparison for extrusion-based bioprinting in the context of breast cancer and melanoma models

Abstract

Biofabrication has proven to be a versatile and valuable tool for tissue engineering and cancer research, enabling the mimicry of various tumor microenvironments. In the present study, four different cell lines, including two melanoma cell lines, Mel Im and Mel Wei, and two breast cancer cell lines, MDA-MB-231 and MCF-7, were tested in combination with four distinct hydrogels. The hydrogels used were a composite ink of alginate, hyaluronic acid, and gelatin (Alg/HA/Gel), pre-crosslinked oxidized alginate with gelatin (ADA-GEL), alginate with methylcellulose (Meth-Alg), and acrylated hyaluronic acid (HAA). Rheological analysis, shear stress calculations, printability assays, and dynamic mechanical analysis were performed on all hydrogels. The cell lines were then mixed into the hydrogels, printed, and examined over 14 days, with a focus on cell survival, metabolic activity, and cell cycle analysis using fluorescent ubiquitination-based cell cycle indicator reporters. The results showed that all hydrogels were printable, with Meth-Alg being the softest gel. The cell lines survived the printing process in all bioinks, but there were significant differences in the metabolic activity and the predominant cell cycle stage. In Alg/HA/Gel, the cells grew in spheroid colonies. ADA-GEL proved to be a good bioink, supporting proliferation, migration, and high metabolic activity across all cell lines, while Meth- Alg offered pore structures conducive to cell spreading and proliferation. However, HAA resulted in the lowest cell number and metabolic activity across all cell lines, likely due to its high polymer content, which induced senescence. Our data demonstrated that each of these bioinks presents unique advantages for breast cancer and melanoma research models.

Keywords

Biofabrication / Bioink / Cell survival / Cell viability / Printability / Tumor