Shue Wang

During tumor growth and progression, cancer cells are exposed to sustained physical confinement and volumetric compression that can alter cell volume, cytoskeletal organization, mechanotransduction, and invasive behavior. However, whether breast cancer cells retain a compression-induced mechanical memory after release from sustained volumetric compression, and how this memory influences subsequent migration and invasion, remains poorly understood. Here, by controlling cell volume using PEG - mediated volumetric compression, we investigated the compression and post-compression recovery responses of MCF-7 breast cancer cells. Cells were compressed for four days, followed by four days of recovery after PEG removal, and analyzed using daily morphological tracking, single-cell time-lapse imaging, F-actin and YAP staining, wound healing assays, and 3D spheroid invasion assays. We show that sustained volumetric compression shifts MCF-7 cells into a compact, jammed-like, low-motility state characterized by reduced morphodynamic remodeling, suppressed collective migration, and limited spheroid invasion. In contrast, post-compression recovery induces a distinct mechanobiological state marked by increased cell area and perimeter, altered single-cell trajectories, heterogeneous F-actin remodeling, enhanced YAP nuclear localization in enlarged recovered cells, accelerated wound closure, and increased spheroid invasion and cell dissemination. These findings suggest that prior volumetric compression can prime breast cancer cells for enhanced migration and invasion after stress release, supporting post-compression recovery as a form of mechanical memory that may contribute to tumor dissemination.

This Research Topic highlights significant advancements in stem cell biology and regenerative medicine, focusing on how engineered microenvironments and physical cues influence cell behaviour. The studies explore the critical interplay between biochemical signals and biophysical forces, such as mechanical confinement, fluid shear stress, and tissue-specific stiffness, in regulating stem cell differentiation and morphogenesis. By utilising innovative tools such as tunable hydrogels, 3D spheroid cultures, and extracellular vesicles (EVs), researchers are developing strategies to overcome current limitations in cell manufacturing, including cellular senescence and delivery precision. These efforts collectively aim to bridge the gap between laboratory innovation and effective clinical therapies for conditions ranging from cartilage injury to bone remodelling disorders.Alsehli et al.investigated how physical confinement imposed by synthetic microenvironments affects the differentiation of human induced pluripotent stem cells (hiPSCs) in 3D spheroid models. Researchers observed that under free culture (suspension) conditions, BMP-4 treatment induces axial elongation of spheroids and differentiation into all three germ layers. However, when cells are physically confined in non-degradable Poly(ethylene Glycol)-PEG hydrogels, morphogenesis is hindered and the expression of differentiation markers, such as SOX17, is drastically reduced. The study demonstrates that differentiation can be rescued using hydrogels that soften over time, suggesting that shape change (morphogenesis) is an essential component for the correct specification of cell fate.Caron et al. explored the mechanosensitive role of the long non-coding RNA (lncRNA) MALAT1 in regulating mesenchymal stem cell (MSC) differentiation under fluid shear stress. The research reveals that physiological levels of shear stress inhibit adipocyte differentiation (fat formation) by reducing lipid droplet accumulation in cells. Using a gapmer double-stranded locked nucleic acid nanobiosensor, the study showed that shear stress downregulated MALAT1, linking an externally applied biomechanical cue to RNA-mediated control of cell fate. Direct silencing of MALAT1 also reduced adipocyte differentiation, confirming that this lncRNA is a key mediator of MSC responses to the mechanical environment of the bone marrow, a crucial factor in understanding disorders such as osteoporosis. More broadly, the work points to lncRNAs as actionable mediators through which engineered physical environments may be translated into lineage-specific outcomes One of the translational barriers to the utilisation of stem cells in regenerative medicine or cell therapy is manufacturing. Even when a cell population has promising therapeutic properties, large-scale expansion can alter phenotype, increase senescence, and compromise biodistribution. Pan et al. tackled this problem in placenta-derived MSCs by alternating conventional 2D expansion with transient 3D spheroid culture. This strategy reduced cell enlargement, delayed senescence, preserved proliferative capacity, and enhanced immunomodulatory activity relative to prolonged 2D culture. Importantly, the authors extended the concept toward scalable production by developing RGD-functionalized alginate hydrogel tubes (AlgTubes), enabling repeated transitions between adherent and spheroid states in a continuous format. This contribution reframes culture architecture as a quality-control variable in cell manufacturing rather than a laboratory convenience (Pan et al., 2025).Yang et al. focused on the potential of mesenchymal stem cells (MSCs) and their extracellular vesicles (EVs) for treating cartilage lesions, which have limited natural repair capacity. Although MSC transplantation is promising, evidence indicates that its regenerative benefits derive mainly from the secretion of EVs rich in bioactive molecules. These vesicles promote chondrocyte proliferation, inhibit apoptosis, modulate local inflammation (polarisation of M1 to M2 macrophages), and assist in the synthesis of the extracellular matrix. The review discusses various sources of extraction (bone marrow, adipose tissue, umbilical cord) and administration methods, including intra-articular injections and hydrogel carriers.Cruz-Gonzalez et al. proposed a paradigm shift in regenerative medicine through a "bottom-up" approach to biomaterial design in which the biological and microenvironmental requirements of stem cells are identified first, and material properties are engineered around those requirements Instead of adapting cells to existing materials, the strategy first focuses on understanding the biological and microenvironmental needs of stem cells (iPSCs, MSCs, ESCs) and then on creating instructive platforms. The review details advances in 3D bioprinting, extracellular matrix (ECM) scaffolds, and the use of "backpack molecules" to improve the precision of cell therapy delivery. The goal was to overcome challenges such as variability in differentiation and low cell survival after transplantation, transforming passive scaffolds into dynamic environments that promote the functional maturity of derived tissues.The collective evidence from these studies demonstrates that the future of regenerative medicine lies in the precise control of the cellular microenvironment. This collection highlights the importance of dynamic physical cues-including confinement, stiffness, softening, shear stress, and geometry-in directing differentiation and maturation, as well as molecular indicators such as lncRNA expression, senescence markers, immunomodulatory mediators, and extracellular vesicle cargo. The findings also emphasise the need to incorporate scalability and standardisation early in development, using platforms such as alternating 2D/3D culture systems and biomaterial-assisted delivery strategies to support reproducible translation. Looking forward, precision regenerative...

Background: Mesenchymal stem cells (MSCs) hold great promise for treating a variety of human diseases; however, their clinical translation is hindered by challenges in large‐scale expansion while preserving therapeutic potency and maintaining small cell size. Conventional 2D culture on rigid substrates induces MSC senescence and enlargement, compromising their function and biodistribution.Methods: We present an alternating 2D/3D culture strategy that combines adherent monolayer expansion with transient spheroid formation to mitigate these limitations. Placenta‐derived MSCs were cultured under optimized spheroid conditions, with extracellular matrix supplementation and chemically defined media to enhance viability. To address scalability, we developed RGD-functionalized alginate hydrogel tubes (AlgTubes) that enable dynamic transitions between adherent and spheroid states for continuous culture.Results: Spheroid culture significantly reduced cell size and enhanced immunomodulatory function. The alternating 2D/3D protocol slowed MSC enlargement and senescence over multiple passages while preserving anti-inflammatory activity. Extracellular matrix supplementation and chemically defined media further improved cell viability. AlgTubes successfully supported the alternating culture strategy in a continuous and scalable format.Conclusions: The alternating 2D/3D culture system effectively overcomes limitations of conventional MSC expansion by mitigating enlargement, delaying senescence, and preserving both proliferative capacity and immunoregulatory potency. Combined with AlgTube technology, this work demonstrates a promising strategy for MSC manufacturing

Mesenchymal stem cells (MSCs) offer significant therapeutic potential, but traditional 2D culture on rigid substrates results in progressive cell enlargement and senescence, reducing proliferative capacity and therapeutic potency. This poses a major challenge for widespread clinical application. We explored a novel strategy for placenta-derived MSCs combining 2D expansion with 3D spheroid culture to address these limitations. Our research shows that culturing MSCs as 3D spheroids significantly reduces individual cell size and size distribution compared to 2D culture. Spheroid formation is feasible in chemically defined media with minimal cell death, and is enhanced by extracellular matrix protein supplementation. Although MSCs do not proliferate in 3D suspension, an alternating 2D/3D culture protocol, transitioning cells between 2D flasks and 3D spheroids after each passage, effectively slows MSC enlargement and senescence over long periods. This alternating method also preserves MSC immunomodulatory function, unlike continuous 2D culture which leads to its loss. For scalability, we developed an RGD-functionalized alginate hydrogel tube (AlgTube) system that mimics this alternating environment, supporting both adherent growth and chemically triggered spheroid formation. This alternating 2D/3D culture strategy and the scalable AlgTube platform provide a foundation for developing next-generation MSC manufacturing technologies to meet future clinical demands.

Ionizing radiation (IR)-induced bone damage presents a major clinical challenge by impairing bone marrow function and disrupting normal bone remodeling. Bone regeneration depends on bone marrow-derived mesenchymal stem cells (BMSCs), which are highly sensitive to IR that causes DNA damage, oxidative stress, apoptosis, and a shift from osteogenesis to adipogenesis, ultimately leading to bone loss and impaired healing. This study evaluated the therapeutic potential of intracellularly delivered bone-derived nanoparticles (BPs) in mitigating IR-induced BMSCs damage. We found that IR exposure caused significant BMSCs dysfunction, including reduced proliferation, increased apoptosis, persistent DNA damage, and a shift toward adipogenic differentiation. Treatment with BPs led to efficient intracellular uptake, improved cell morphology, enhanced proliferation, reduced apoptosis, and preservation of balanced differentiation capacity. Transcriptomic analysis via RNA sequencing revealed that BPs restored key molecular pathways disrupted by IR, particularly those involved in cell cycle regulation, extracellular matrix (ECM) remodeling, and apoptosis. By reversing these transcriptional impairments, BPs supported genomic stability and the regenerat ive function of BMSCs. Overall, these findings suggest that BPs effectively counteract IR-induced cellular damage and enhance the regenerative capacity of BMSCs, offering a promising therapeutic strategy for radiation -induced skeletal injuries.

Adipocyte differentiation plays an important role in bone remodeling due to secretory factors that can directly modulate osteoblast and osteoclast, thus affecting overall bone mass and skeletal integrity. Excessive adipocyte differentiation within the bone marrow microenvironment can lead to decreased bone mass, eventually causing osteoporosis. The mechanical microenvironment of bone marrow, including fluid shear, maintains the balance of adipocyte and osteoblast differentiation during bone remodeling. However, how mechanical cues interact with long noncoding RNA (lncRNA) and regulate adipocyte differentiation remains unexplored. In this study, we investigated the mechanosensitive role of lncRNA MALAT1 during mesenchymal stem cells (MSCs) adipocyte differentiation. By applying physiologically relevant shear stress, MSCs experienced morphological changes and adipocyte differentiation differences. Shear stress inhibits adipocyte differentiation of MSCs, demonstrated by reduced oil-red-o-stained lipid droplets. Silencing MALAT1 also results in reduced adipocyte differentiation. By leveraging a novel gapmer double stranded locked nuclei acid nanobiosensor, we showed that shear stress inhibits MALAT1 expression, with significantly reduced fluorescence intensity. Our findings indicate that shear stress influences adipocyte differentiation mainly through the downregulation of MALAT1, highlighting a significant interplay between biophysical cues and lncRNAs. This interaction is crucial for understanding the complexities of bone remodeling and the potential therapeutic targeting of lncRNAs to treat bone-related disorders.

Traditional livestock farming is resource-intensive and environmentally unsustainable, necessitating alternative methods for meat production. Cell cultured meat, produced by expanding and differentiating animal cells, offers great potential for substituting for conventional animal meat. Nevertheless, it is still limited by the scalability and efficiency of current cell culture technologies. In this study, we developed an RGD peptide-modified alginate hydrogel microtube microbioreactor (AlgTubes) to support the scalable culture of anchor-dependent cells, such as myoblasts and adipocytes, for cell-cultured meat production. AlgTubes provide a cell-friendly 3D microenvironment that enhances cell viability, growth, and yield while overcoming limitations of conventional bioreactors, such as shear stress, aggregation, and diffusion constraints. We successfully expanded mouse (C2C12) and quail (QM7) myoblasts in AlgTubes, achieving cell densities exceeding 1.0 × 10⁸ cells/mL, far surpassing traditional stirred-tank bioreactors. Differentiation resulted in the formation of mature myotubes. Co-culturing myoblasts with mesenchymal stem cells or fibroblasts further improved yield and viability, particularly under differentiation conditions. By significantly increasing cell culture density, AlgTubes can substantially reduce culture volume, lowering labor requirements, reagent costs, equipment needs, facility space, and manufacturing expenses.

The large-scale production of mammalian cells is pivotal for various applications; however, current bioreactor technologies encounter significant technical and economic challenges. Scaling up cell cultures remains problematic due to excessive cell aggregation, shear stress-induced cell death, batch-to-batch inconsistencies, and limited scalability. We propose that engineering a cell-friendly microenvironment can enhance culture efficiency. Previously, we developed alginate hydrogel microtubes (AlgTubes) that significantly improved cell density and growth rates. Nevertheless, AlgTubes lack adhesion sites essential for anchorage-dependent cells and frequently break, causing cell leakage and production inconsistencies. To address these limitations, this study reinforced AlgTubes with collagen nanofibers, creating collagen-alginate hybrid hydrogel microtubes (ColAlgTubes). Utilizing a novel micro-extruder, we efficiently produced cell-loaded ColAlgTubes. Collagen formed a dense nanofiber network interwoven with the alginate mesh, enhancing the hydrogel’s mechanical properties while providing cell adhesion sites. ColAlgTubes protected cells from hydrodynamic stress and maintained cell mass within a 400 μm diameter, ensuring efficient nutrient exchange and waste removal. This optimized microenvironment resulted in high cell viability, rapid proliferation, and exceptional yields of 5×10 ⁸ cells/mL - 200 times higher than conventional culture methods. With their scalability, cost-effectiveness, and efficiency, ColAlgTubes offers a transformative solution for large-scale cell production with broad applications in biotechnology, regenerative medicine, and therapeutic manufacturing.

Adipocyte differentiation plays an important role in bone remodeling due to secretory factors that can directly modulate osteoblast and osteoclast, thus affecting overall bone mass and skeletal integrity. Excessive adipocyte differentiation within bone marrow microenvironment can lead to decreased bone mass, eventually causing osteoporosis. Mechanical microenvironment of bone marrow, including fluid shear, maintains the balance of adipocyte and osteoblast differentiation during bone remodeling. However, how mechanical cues interact with long noncoding RNA (lncRNA) and regulating adipocyte differentiation remains unexplored. In this study, we investigated the mechanosensitive role of lncRNA MALAT1 during mesenchymal stem cells (MSCs) adipocyte differentiation. By applying physiologically relevant shear stress, MSCs experienced morphological changes and adipocyte differentiation differences. Shear stress inhibits MSCs adipocyte differentiation with reduced oil-red-o-stained lipid droplets. Silencing MALATs results in reduced adipocyte differentiation. By leveraging a novel gapmer double stranded locked nuclei acid (dsLNA) nanobiosensor, we showed that shear stress inhibits MALAT1 expression with significantly reduced fluorescence intensity. Our findings suggest that shear stress influences adipocyte differentiation primarily through the downregulation of MALAT1, highlighting a significant interplay between biophysical cues and lncRNAs. This interaction is crucial for understanding the complexities of bone remodeling and the potential therapeutic targeting of lncRNAs to treat bone-related disorders.