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

Abstract

Glioblastoma 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 are largely unknown. Soluble angiocrine factors secreted by tumor-associated vasculature have been shown to support such behaviors in other cancer types. Here, we exploit macroscopic and microfluidic gelatin hydrogel platforms to profile angiocrine factors secreted by self-assembled endothelial networks and evaluate their relevance to glioblastoma biology.Aggregate angiocrine factors support U87-MG proliferation, migration, and therapeutic resistance to temozolomide. We also identify a novel role for TIMP1 in facilitating glioblastoma tumor cell migration. Overall, this work highlights the use of multidimensional hydrogel models to evaluate the role of angiocrine signals in glioblastoma progression. Glioblastoma progression is linked to interactions between tumor and vascular cells, which caninfluence invasion and therapeutic response. In co-culture studies to investigate tumor-vascular crosstalk, endothelial cells often are not presented in three-dimensional structures mimicking vasculature and the exact identity of secreted factors is not explored. Here, we use tissue engineering strategies to generate three-dimensional endothelial networks from which to collect soluble angiocrine signals and assess the impact of these signals on glioblastoma behavior. Furthermore, we use secretomic analysis to identify specific factors influencing glioblastoma

Crosstalk between microglia and patient-derived glioblastoma cells inhibit invasion in a three-dimensional gelatin hydrogel model

“…Here, we report a multidimensional hydrogel platform to examine pathophysiological processes linked to GBM progression and mortality using patient-derived GBM specimens in response to microglia. We have also recently described hydrogel-based platforms to investigate the role of angiocrine signaling from engineered perivascular cultures on GBM cell invasion and resistance to the frontline chemotherapy temozolomide [57]. We also reported adaptations to the hydrogel environment via localized formation of hypoxic zone to support culture of a broader diversity of cells from the neurovascular unit [58].…”

“…We have previously developed a family of gelatin hydrogels to investigate pathophysiological processes underlying glioblastoma invasion and progression. Extensive biophysical performance data has previously been reported including network architecture and mechanical performance [52,53], water and small-molecule diffusivity [54][55][56], and the capacity to support growth and phenotypic studies of primary glioblastoma cells and cells from the neurovascular unit [57,58]. For this project, GBM and MG cells were maintained in three-dimensional culture in a 4 wt% methacrylamide-functionalized gelatin (GelMA) that exhibited a physiologically relevant Young's modulus (1.04 ± 0.10 kPa; n = 14; Fig.…”

“…Notably, we observed that biophysical (hyaluronan content and molecular weight) and metabolic (hypoxia) transitions in the GBM tumor microenvironment both significantly alter GBM invasion [30][31][32]. More recently, we adapted this system to profile cytokine-based crosstalk between cells within the GBM tumor microenvironment, identifying secreted factors generated by an artificial perivascular niche that can accelerate GBM cell invasion [33]. The objective of the present study was to adapt this established hydrogel platform and cytokine analysis protocols to examine the effects of microglia within the GBM tumor microenvironment on GBM gene expression and invasiveness using patient-derived GBM specimens that maintain patientspecific morphologic and molecular phenotypes [34,35].…”

Perivascular Secretome Influences Hematopoietic Stem Cell Maintenance in a Gelatin Hydrogel

“…43 More recently, we showed 20 paracrine signals from marrow-derived mesenchymal stem cells could enhance the retention of quiescent HSCs, 26 though this effect was also strongly dependent on the relative ratio of HSCs to MSCs as well as on processes of MSC-mediated hydrogel remodeling. Separately, a wide range of studies have focused on developing microphysiological models of the perivascular environment to interrogate processes associated with disease progression, 9,29,54,55 cancer invasion or metastasis, 4,37,50,51,66 and even dormancy of cancer stem cells. 10,24 These studies provide an illustrative example of the power of the perivascular environment and motivate our study of the role of perivascular signals on murine HSC culture.…”

Crosstalk between microglia and patient-derived glioblastoma cells inhibit invasion in a three-dimensional gelatin hydrogel model

“…Notably, we observed that biophysical (hyaluronan content and molecular weight) and metabolic (hypoxia) transitions in the GBM tumor microenvironment both significantly alter GBM invasion [30][31][32]. More recently, we adapted this system to profile cytokine-based crosstalk between cells within the GBM tumor microenvironment, identifying secreted factors generated by an artificial perivascular niche that can accelerate GBM cell invasion [33]. The objective of the present study was to adapt this established hydrogel platform and cytokine analysis protocols to examine the effects of microglia within the GBM tumor microenvironment on GBM gene expression and invasiveness using patient-derived GBM specimens that maintain patient-specific morphologic and molecular phenotypes [34,35].…”