Tissue-Engineered Brain-Mimetic Niches to Model Braintropic Triple-Negative Breast Cancer Metastasis.

Area of Science:

• Biomedical Engineering
• Cancer Biology
• Neuro-oncology

Background:

• Triple-negative breast cancer (TNBC) brain metastases are aggressive, leading to poor prognosis and limited treatment options.
• Developing accurate in vitro models that mimic the brain microenvironment is essential for advancing therapeutic development.
• Existing models often fail to replicate the complex biochemical and mechanical cues of the premetastatic niche.

Purpose of the Study:

• To investigate the impact of a brain-mimetic microenvironment on TNBC cell behavior in vitro.
• To quantify the influence of adhesion, degradation, and cell type on TNBC brain metastasis models.
• To compare cell responses in brain-mimetic niches versus generic RGDS-functionalized niches.

Main Methods:

• Encapsulating and culturing TNBC cell lines (MDA-MB-231 and MDA-MB-231-BrM2a-831) in three distinct biomimetic niches.
• Functionalizing niches with a brain-mimetic peptide cocktail to replicate brain extracellular matrix properties.
• Comparing cell responses, including adhesion, degradation, proliferation, and morphology, across different niche conditions.

Main Results:

• Brain-mimetic adhesion minimally affected the parental TNBC cells (P231).
• Braintropic TNBC cells (BrM2a) exhibited reduced viable cell density and proliferation in brain-mimetic niches.
• BrM2a cells showed a higher proportion of spherical clusters and individual cells, indicating a less invasive phenotype.

Conclusions:

• Brain-mimetic microenvironments significantly influence the phenotype of braintropic TNBC cells, promoting a less invasive, rounded morphology.
• These advanced biomimetic in vitro models offer improved recapitulation of in vivo cell behavior for preclinical testing.
• The findings highlight the potential of targeting microenvironmental interactions for novel therapeutic strategies against TNBC brain metastases.