Modeling Uterine Fibroids Using Bioengineered Hydrogels.

Uterine fibroids are the most common gynecological tumors, characterized by excessive production of extracellular matrix. Despite their prevalence, the cellular mechanisms governing fibroid growth remain poorly understood. Current in vitro models for fibroids do not replicate the complex 3D tissue mechanics, structure, and extracellular matrix components of fibroids, which may limit our understanding of fibroid pathogenesis. To address this gap, we aimed to develop a 3D in vitro model to mimic aspects of the fibroid microenvironment. By encapsulating human uterine fibroblasts in poly(ethylene glycol) (PEG)-based hydrogels comprising collagen- and fibronectin-derived peptides, this model allows for incorporation of fibroid cellular components, extracellular matrix components, and fibroid or myometrial tissue stiffness. Due to its mechanistic role in fibroblast activation and subsequent extracellular matrix production seen in fibroids, we treated uterine fibroblasts with transforming growth factor beta 3 (TGF-β3) to demonstrate quantification of fibrotic markers observed in fibroids. Here, we establish that human uterine fibroblasts increase α smooth muscle actin, extracellular matrix proteins, and cell elongation, as well as high metabolic activity and matrix remodeling in PEG-based hydrogels in response to TGF-β3. This research represents a physiologically relevant in vitro platform to investigate uterine fibroblast function within a 3D environment that mimics uterine fibroids, with the potential to advance our understanding of the cellular and molecular mechanisms driving fibroid growth and development.