Perivascular Stromal Cells Instruct Glioblastoma Invasion, Proliferation, and Therapeutic Response within an Engineered Brain Perivascular Niche Model.

Glioblastoma (GBM) tumor cells are found in the perivascular niche microenvironment and are believed to associate closely with the brain microvasculature. However, it is largely unknown how the resident cells of the perivascular niche, such as endothelial cells, pericytes, and astrocytes, influence GBM tumor cell behavior and disease progression. A 3D in vitro model of the brain perivascular niche developed by encapsulating brain-derived endothelial cells, pericytes, and astrocytes in a gelatin hydrogel is described.

Hydrogels Containing Gradients in Vascular Density Reveal Dose-Dependent Role of Angiocrine Cues on Stem Cell Behavior.

Biomaterials that replicate patterns of microenvironmental signals from the stem cell niche offer the potential to refine platforms to regulate stem cell behavior. While significant emphasis has been placed on understanding the effects of biophysical and biochemical cues on stem cell fate, vascular-derived or angiocrine cues offer an important alternative signaling axis for biomaterial-based stem cell platforms. Elucidating dose-dependent relationships between angiocrine cues and stem cell fate are largely intractable in animal models and 2D cell cultures.

Three-dimensional hydrogel culture systems support growth and determination of chemosensitivity of feline sarcoma and carcinoma cell lines.

Objective: To evaluate feline injection site-associated sarcoma (FISAS) and oral squamous cell carcinoma (FOSCC) cells in 3-D hydrogel-based cell cultures to determine chemosensitivity to carboplatin at concentrations comparable to those eluted from carboplatin-impregnated calcium sulfate hemihydrate (C-ICSH) beads.

Sample: 2 immortalized cell lines, each from a histologically confirmed primary FISAS and FOSCC.

Procedures: Hydrogels (10% wt/vol) were formed via UV exposure from methacrylamide-functionalized gelatin dissolved in PBSS.

Three-dimensional hydrogel culture systems support growth and determination of chemosensitivity of feline sarcoma and carcinoma cell lines.

Objective: To evaluate feline injection site-associated sarcoma (FISAS) and oral squamous cell carcinoma (FOSCC) cells in 3-D hydrogel-based cell cultures to determine chemosensitivity to carboplatin at concentrations comparable to those eluted from carboplatin-impregnated calcium sulfate hemihydrate (C-ICSH) beads.

Sample: 2 immortalized cell lines, each from a histologically confirmed primary FISAS and FOSCC.

Procedures: Hydrogels (10% wt/vol) were formed via UV exposure from methacrylamide-functionalized gelatin dissolved in PBSS.

Sibling bullying among Vietnamese children: the relation with peer bullying and subjective well-being.

Background: Siblings play an important role in a child's life. However, many children often experience sibling bullying. This study investigates differences in sibling victimization by sex, age, a parent's absence from the home due to employment, or a child's privacy and the relationship between sibling victimization, peer victimization, and the child's well-being.

Glycosaminoglycan content of a mineralized collagen scaffold promotes mesenchymal stem cell secretion of factors to modulate angiogenesis and monocyte differentiation.

Effective design of biomaterials to aid regenerative repair of craniomaxillofacial (CMF) bone defects requires approaches that modulate the complex interplay between exogenously added progenitor cells and cells in the wound microenvironment, such as osteoblasts, osteoclasts, endothelial cells, and immune cells. We are exploring the role of the glycosaminoglycan (GAG) content in a class of mineralized collagen scaffolds recently shown to promote osteogenesis and healing of craniofacial bone defects. We previously showed that incorporating chondroitin-6-sulfate or heparin improved mineral deposition by seeded human mesenchymal stem cells (hMSCs).

Encapsulation of murine hematopoietic stem and progenitor cells in a thiol-crosslinked maleimide-functionalized gelatin hydrogel.

Biomaterial platforms are an integral part of stem cell biomanufacturing protocols. The collective biophysical, biochemical, and cellular cues of the stem cell niche microenvironment play an important role in regulating stem cell fate decisions. Three-dimensional (3D) culture of stem cells within biomaterials provides a route to present biophysical and biochemical stimuli through cell-matrix interactions and cell-cell interactions via secreted biomolecules.

Progress in mimicking brain microenvironments to understand and treat neurological disorders.

Neurological disorders including traumatic brain injury, stroke, primary and metastatic brain tumors, and neurodegenerative diseases affect millions of people worldwide. Disease progression is accompanied by changes in the brain microenvironment, but how these shifts in biochemical, biophysical, and cellular properties contribute to repair outcomes or continued degeneration is largely unknown. Tissue engineering approaches can be used to develop models to understand how the brain microenvironment contributes to pathophysiological processes linked to neurological disorders and may also offer constructs that promote healing and regeneration .

Angiogenic biomaterials to promote therapeutic regeneration and investigate disease progression.

The vasculature is a key component of the tissue microenvironment. Traditionally known for its role in providing nutrients and oxygen to surrounding cells, the vasculature is now also acknowledged to provide signaling cues that influence biological outcomes in regeneration and disease. These cues come from the cells that comprise vasculature, as well as the dynamic biophysical and biochemical properties of the surrounding extracellular matrix that accompany vascular development and remodeling.

Multidimensional hydrogel models reveal endothelial network angiocrine signals increase glioblastoma cell number, invasion, and temozolomide resistance.

Glioblastoma (GBM) is the most common primary malignant brain tumor. The tissue microenvironment adjacent to vasculature, termed the perivascular niche, has been implicated in promoting biological processes involved in glioblastoma progression such as invasion, proliferation, and therapeutic resistance. However, the exact nature of the cues that support tumor cell aggression in this niche is largely unknown.

Perivascular signals alter global gene expression profile of glioblastoma and response to temozolomide in a gelatin hydrogel.

Glioblastoma (GBM) is the most common primary malignant brain tumor, with patients exhibiting poor survival (median survival time: 15 months). Difficulties in treating GBM include not only the inability to resect the diffusively-invading tumor cells, but also therapeutic resistance. The perivascular niche (PVN) within the GBM tumor microenvironment contributes significantly to tumor cell invasion, cancer stem cell maintenance, and has been shown to protect tumor cells from radiation and chemotherapy.

The Influence of Hyaluronic Acid and Glioblastoma Cell Coculture on the Formation of Endothelial Cell Networks in Gelatin Hydrogels.

Glioblastoma (GBM) is the most common and deadly form of brain cancer. Interactions between GBM cells and vasculature in vivo contribute to poor clinical outcomes, with GBM-induced vessel co-option, regression, and subsequent angiogenesis strongly influencing GBM invasion. Here, elements of the GBM perivascular niche are incorporated into a methacrylamide-functionalized gelatin hydrogel as a means to examine GBM-vessel interactions.