Microenvironment complexity and matrix stiffness regulate breast cancer cell activity in a 3D in vitro model

Area of Science:

• Biomaterials Science
• Cell Biology
• Cancer Research

Background:

• Three-dimensional (3D) cell cultures are essential for understanding cellular processes in health and disease.
• Mechanical and chemical cues critically influence cell fate, cancer development, and progression.

Purpose of the Study:

• To investigate the impact of substrate elasticity on breast adenocarcinoma cell activity using mechanically tuned alginate hydrogels.
• To compare cell behavior in 3D hydrogel cultures with traditional 2D culture systems.

Main Methods:

• Fabrication of alginate hydrogels with tunable elastic moduli (150-4000 kPa), measured by atomic force microscopy (AFM).
• Culture of MCF-7 breast cancer cells within 3D hydrogels and on 2D substrates (Petri dishes, alginate-coated dishes).
• Analysis of cell morphology, viability, and proliferation rates in response to varying substrate elasticity.

Main Results:

• Cells cultured in 3D hydrogels adopted a spheroid, clustered morphology, unlike the flat shape in 2D cultures.
• A significant inverse correlation was observed between substrate elasticity and MCF-7 cell viability.
• Maximal cell proliferation and cluster formation occurred in the softest hydrogels (150-200 kPa) after two weeks.

Conclusions:

• Substrate stiffness is a critical factor influencing breast cancer cell behavior in vitro.
• Softer, more physiologically relevant 3D models are necessary for accurate in vitro cancer research.
• Alginate hydrogels offer a tunable platform for studying mechanobiology in cancer models.