Extracellular Matrix Interactions in Mammary Epithelial Biology

The mammary gland epitomises a dynamic tissue in which epithelial cells interact intimately with a specialised extracellular matrix (ECM) to control development, morphogenesis and homeostasis. In the normal gland, a basement membrane rich in laminins and type IV collagen underlies luminal and myoepithelial cells, providing both structural support and context-dependent biochemical cues. Through receptors such as integrins, epithelial cells sense matrix stiffness and composition, transducing mechanical signals into pathways that regulate proliferation, differentiation and polarity. During ductal branching and lobuloalveolar formation, local remodelling of fibrillar collagens and proteolytic processing by matrix metalloproteinases orchestrates epithelial invasion into the stroma while preserving tissue architecture. Hormonal cycles further modulate ECM remodelling to enable cyclical expansion and involution. In pathophysiological contexts, altered matrix composition, increased stiffness and dysregulated cell–matrix adhesion cooperate to drive malignant transformation, invasion and metastasis. Advances in three-dimensional culture systems, microfluidic platforms and synthetic hydrogels have begun to recapitulate the native microenvironment, elucidating the interplay between mechanical forces, matrix chemistry and epithelial signalling with implications for tissue engineering and anti-cancer strategies.

Research from Nature Portfolio

Studies using three-dimensional collagen matrices have revealed that exposure of mammary epithelial cells to a fibrillar stromal environment triggers a mechanosensitive programme of invasion. Defined collagen gels promote expression of matrix metalloproteinases and engage Src–PI3K–Rac1 signalling in epithelial cells, converting otherwise quiescent followers into active invaders in co-culture models. Separately, a synthetic modular hydrogel system employing peptide-functionalised poly(ethylene glycol) with matrix-degradable crosslinkers and adhesive ligands has been shown to support both two- and three-dimensional cultures of tumour and epithelial cells. By tuning stiffness and proteolytic sensitivity, this platform recapitulates single-cell migration, cluster growth and collective invasion modes, offering a flexible tool to probe ECM remodelling and tumour progression in a fully defined microenvironment.

Extracellular Matrix Interactions in Mammary Epithelial Biology publication trend

The graph below shows the total number of articles in extracellular matrix interactions in mammary epithelial biology across all publications each year (not limited to Nature Index journals).

Technical terms

Extracellular matrix (ECM): A complex network of proteins and polysaccharides that provides structural scaffolding and biochemical signals to cells.

Basement membrane: A specialised ECM layer rich in laminins and type IV collagen that underlies epithelial sheets and regulates polarity and differentiation.

Mechanotransduction: The process by which cells convert mechanical inputs, such as matrix stiffness, into intracellular chemical signals.

Integrin: A family of transmembrane receptors that mediate cell–ECM adhesion and initiate signalling pathways controlling survival, proliferation and migration.

Organoid: A three-dimensional multicellular structure grown in vitro that recapitulates key features of the tissue of origin, including architecture and function.

References

1. Sustained postconfluent culture of human mammary epithelial cells enriches for luminal and c-Kit+ subtypes. Breast Cancer Research (2023).
2. An in vitro model of cancer invasion with heterogeneous ECM created with droplet microfluidics. Frontiers in Bioengineering and Biotechnology (2023).
3. Cellular Plasticity in Mammary Gland Development and Breast Cancer. Cancers (2023).
4. Three-dimensional collagen matrix induces a mechanosensitive invasive epithelial phenotype. Scientific Reports (2017).
5. A synthetic modular approach for modeling the role of the 3D microenvironment in tumor progression. Scientific Reports (2015).