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Beeghly, G. F.

Publications and source records attributed to Beeghly, G. F..

3 recordsLinked to original sources

Adipose-mimetic granular hydrogels uncover biophysical cues driving breast cancer invasion

1.Breast cancer cells invade mammary adipose tissue during initial stages of metastasis but how the physical properties of adipose tissue regulate this process remains unclear. Here, we combined single cell mechanical characterization of primary adipocytes with microfluidic hydrogel fabrication, quantitative multiparametric imaging, Discrete Element Method (DEM) simulations, and in vivo experiments to elucidate these connections. First, we quantified the heterogeneous size and stiffness of primary adipocytes, and replicated these properties by fabricating adipocyte-sized polyacrylamide (PAAm) beads with tunable elasticity. Subsequently, we embedded these beads into type I collagen, the primary fibrillar extracellular matrix (ECM) component of breast adipose tissue, to form 3D granular hydrogels mimicking aspects of native adipose tissue architecture. Granular hydrogels embedded with beads demonstrated increased breast cancer cell invasion relative to bead-free controls, an effect that was more pronounced with soft versus stiff beads and correlated with increased collagen fiber alignment and hierarchical organization. In addition, live cell imaging and DEM simulations revealed that soft beads promoted invasion relative to stiff beads by deforming in response to confined cancer cell migration. Fiber alignment and adipocyte deformation trends were validated in vivo via intravital imaging of cancer cell migration in mammary fat pads of mice, and suggest that adipocyte mechanics regulate breast cancer invasion by coordinating both ECM architecture and cellular confinement. Ultimately, this work highlights the utility of tunable PAAm bead-collagen composites as micromechanical models to study the effect of adipose tissue structure on cancer cell invasion. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=106 SRC="FIGDIR/small/684224v1_ufig1.gif" ALT="Figure 1"> View larger version (56K): org.highwire.dtl.DTLVardef@d3ce0org.highwire.dtl.DTLVardef@117abb1org.highwire.dtl.DTLVardef@10917faorg.highwire.dtl.DTLVardef@55f3e_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical Abstract:C_FLOATNO Polyacrylamide bead granular hydrogels recapitulate adipose tissue structure and alter cancer cell invasion in a stiffness-dependent manner. The invasion of primary breast cancer cells through mammary adipose is influenced by the heterogeneous mechanical properties of native stromal components, namely adipocytes and extracellular matrix (left). Customizable granular hydrogels provide insight into the physical regulation of breast cancer progression by mimicking adipose tissue extracellular matrix structure (collagen I, i.) and stromal cell mechanics (polyacrylamide bead, ii.), whereby the inclusion of soft beads and/or dilute matrix promotes cancer cell migration compared to stiffer hydrogels (right). C_FIG

bioengineering↗

Hypertrophic adipocytes increase extracellular vesicle-mediated lipid release and reprogram breast cancer cell metabolism

Primary adipocytes possess a dramatic capacity to expand and retract in volume, leading to high variability in cell size within and between individuals. Yet, how adipocyte size impacts cell function remains unclear as adipocyte size is not tunable with traditional experimental approaches, forcing previous work to rely on correlative studies. Here, we develop protocols to separate primary adipocytes from the same donor into large and small populations and maintain these size-sorted cells in culture. Using these methods, we perform transcriptomic, lipidomic, and functional analyses on large and small adipocytes across two orthogonal mouse models of obesity and validate our results with human clinical samples. Our findings indicate that changes to cell size, rather than global differences mediated by weight gain, drive the transcriptional response of primary adipocytes to obesity. Moreover, large adipocytes shift from a traditional, lipase-mediated mode of lipid release to a non-canonical, extracellular vesicle-mediated mechanism. In functional coculture studies, this change promotes lipid accumulation in neighboring breast cancer cells, increasing their migration and proliferation via enhanced tumor cell fatty acid oxidation. Consistent with our experimental data, human patients with large adipocytes present with greater rates of dyslipidemia and higher concentrations of fasting triglycerides, even when accounting for differences in body mass index. Collectively, our results provide direct evidence that large and small adipocytes from the same donor differ in gene expression, lipid composition, and function with implications for the management of adipose tissue-related pathologies such as breast cancer.

cell biology↗

A patient-designed tissue-engineered model of the infiltrative glioblastoma microenvironment

Glioblastoma is an aggressive brain cancer characterized by diffuse infiltration. Infiltrated glioma cells persist in the brain post-resection where they interact with glial cells and experience interstitial fluid flow. We recreate this infiltrative microenvironment in vitro based on resected patient tumors and examine malignancy metrics (invasion, proliferation, and stemness) in the context of cellular and biophysical factors and therapies. Our 3D tissue-engineered model comprises patient-derived glioma stem cells, human astrocytes and microglia, and interstitial fluid flow. We found flow contributes to all outcomes across seven patient-derived lines, and glial effects are driven by CCL2 and differential glial activation. We conducted a six-drug screen using four outcomes and find expression of putative stemness marker CD71, opposed to viability IC50, significantly predicts murine xenograft survival. Our results dispute the paradigm of viability as predictive of drug efficacy. We posit this patient-centric, infiltrative tumor model is a novel advance towards translational personalized medicine.

bioengineering↗