An official website of the United States government
Abstract Microfluidic devices that combine an extracellular matrix environment, cells, and physiologically relevant perfusion, are advantageous as cell culture platforms. We developed a hydrogel-based, microfluidic cell culture platform by loading polyethylene glycol (PEG) hydrogel-encapsulated U87 glioblastoma cells into membrane-capped wells in polydimethyl siloxane (PDMS). The multilayer microfluidic cell culture system combines previously reported design features in a configuration that loads and biomimetically perfuses a 2D array of cell culture chambers. One dimension of the array is fed by a microfluidic concentration gradient generator (MCGG) while the orthogonal dimension provides loading channels that fill rows of cell culture chambers in a separate layer. In contrast to typical tree-like MCGG mixers, a fractional serial dilution of 1, ½, ¼, and 0 of the initial solute concentration is achieved by tailoring the input microchannel widths. Hydrogels are efficiently and reproducibly loaded in all wells and cells are evenly distributed throughout the hydrogel, maintaining > 90% viability for up to 4 days. In a drug screening assay, diffusion of temozolomide and carmustine to hydrogel-encapsulated U87 cells from the perfusion solution is measured, and dose–response curves are generated, demonstrating utility as an in vitro mimic of the glioblastoma microenvironment.
more »
« less
The application of electrosprayed minocycline‐loaded PLGA microparticles for the treatment of glioblastoma
Abstract The survival of patients with glioblastoma multiforme (GBM), the most common and invasive form of malignant brain tumors, remains poor despite advances in current treatment methods including surgery, radiotherapy, and chemotherapy. Minocycline is a semi‐synthetic tetracycline derivative that has been widely used as an antibiotic and more recently, it has been utilized as an antiangiogenic factor to inhibit tumorigenesis. The objective of this study was to investigate the utilization of electrospraying process to fabricate minocycline‐loaded poly(lactic‐co‐glycolic acid) (PLGA) microparticles with high drug loading and loading efficiency and to evaluate their ability to induce cell toxicity in human glioblastoma (i.e., U87‐MG) cells. The results from this study demonstrated that solvent mixture of dicholoromethane (DCM) and methanol is the optimal solvent combination for minocycline and larger amount of methanol (i.e., 70:30) resulted in a higher drug loading. All three solvent ratios of DCM:methanol tested produced microparticles that were both spherical and smooth, all in the micron size range. The electrosprayed microparticles were able to elicit a cytotoxic response in U87‐MG glioblastoma cells at a lower concentration of drug compared to the free drug. This work provides proof of concept to the hypothesis that electrosprayed minocycline‐loaded PLGA microparticles can be a promising agent for the treatment of GBM and could have potential application for cancer therapies.
more »
« less
- Award ID(s):
- 2122178
- PAR ID:
- 10469032
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Biotechnology and Bioengineering
- Volume:
- 120
- Issue:
- 11
- ISSN:
- 0006-3592
- Format(s):
- Medium: X Size: p. 3409-3422
- Size(s):
- p. 3409-3422
- Sponsoring Org:
- National Science Foundation
More Like this
-
-
Abstract BackgroundGlioblastoma Multiforme, an aggressive primary brain tumor, has a poor prognosis and no effective standard of care treatments. Most patients undergoing radiotherapy, along with Temozolomide chemotherapy, develop resistance to the drug, and recurrence of the tumor is a common issue after the treatment. We propose to model the pathways active in Glioblastoma using Boolean network techniques. The network captures the genetic interactions and possible mutations that are involved in the development of the brain tumor. The model is used to predict the theoretical efficacies of drugs for the treatment of cancer. ResultsWe use the Boolean network to rank the critical intervention points in the pathway to predict an effective therapeutic strategy for Glioblastoma. Drug repurposing helps to identify non-cancer drugs that could be effective in cancer treatment. We predict the effectiveness of drug combinations of anti-cancer and non-cancer drugs for Glioblastoma. ConclusionsGiven the genetic profile of a GBM tumor, the Boolean model can predict the most effective targets for treatment. We also identified two-drug combinations that could be more effective in killing GBM cells than conventional chemotherapeutic agents. The non-cancer drug Aspirin could potentially increase the cytotoxicity of TMZ in GBM patients.more » « less
-
Glioblastoma (GBM) is highly resistant to treatment and invasion into the surrounding brain is a cancer hallmark that leads to recurrence despite surgical resection. With the emergence of precision medicine, patient-derived 3D systems are considered potentially robust GBM preclinical models. In this study, we screened a library of 22 anti-invasive compounds (i.e., NF-kB, GSK-3-B, COX-2, and tubulin inhibitors) using glioblastoma U-251 MG cell spheroids. We evaluated toxicity and invasion inhibition using a 3D Matrigel invasion assay. We next selected three compounds that inhibited invasion and screened them in patient-derived glioblastoma organoids (GBOs). We developed a platform using available macros for FIJI/ImageJ to quantify invasion from the outer margin of organoids. Our data demonstrated that a high-throughput invasion screening can be done using both an established cell line and patient-derived 3D model systems. Tubulin inhibitor compounds had the best efficacy with U-251 MG cells, however, in ex vivo patient organoids the results were highly variable. Our results indicate that the efficacy of compounds is highly related to patient intra and inter-tumor heterogeneity. These results indicate that such models can be used to evaluate personal oncology therapeutic strategies.more » « less
-
Abstract Glioblastoma (GBM) is hard to treat due to cellular invasion into functioning brain tissues, limited drug delivery, and evolved treatment resistance. Recurrence is nearly universal even after surgery, chemotherapy, and radiation. Photodynamic therapy (PDT) involves photosensitizer administration followed by light activation to generate reactive oxygen species at tumor sites, thereby killing cells or inducing biological changes. PDT can ablate unresectable GBM and sensitize tumors to chemotherapy. Verteporfin (VP) is a promising photosensitizer that relies on liposomal carriers for clinical use. While lipids increase VP's solubility, they also reduce intracellular photosensitizer accumulation. Here, a pure‐drug nanoformulation of VP, termed “NanoVP”, eliminating the need for lipids, excipients, or stabilizers is reported. NanoVP has a tunable size (65–150 nm) and 1500‐fold higher photosensitizer loading capacity than liposomal VP. NanoVP shows a 2‐fold increase in photosensitizer uptake and superior PDT efficacy in GBM cells compared to liposomal VP. In mouse models, NanoVP‐PDT improved tumor control and extended animal survival, outperforming liposomal VP and 5‐aminolevulinic acid (5‐ALA). Moreover, low‐dose NanoVP‐PDT can safely open the blood‐brain barrier, increasing drug accumulation in rat brains by 5.5‐fold compared to 5‐ALA. NanoVP is a new photosensitizer formulation that has the potential to facilitate PDT for the treatment of GBM.more » « less
-
Glioblastoma (GBM) is the most aggressive cancer originating in the brain, but unfortunately combination treatments with resection, radiation, and chemotherapy are relatively ineffective. Therefore, novel methods of adjuvant therapy are critically needed. Cyclotides are plant-derived circular peptides that chemosensitize drug-resistant breast cancer to doxorubicin. We analyzed naturally occurring and synthetic cyclotides (Cycloviolacin O3, Cycloviolacin O19, natural Kalata B1, synthetic Kalata B1, and Vitri E) alone and in co-exposure treatments with the drug temozolomide (TMZ) in human glioblastoma cells. The cyclotides were identified by UPLC-PDA and HPLC-UV. The synthetic Kalata B1 sequence was verified with orbitrap LC-MS, and structural confirmation was provided by NMR spectroscopy. The cyclotides displayed dose-dependent cytotoxicity (IC50 values 2.4–21.1 µM) both alone and as chemosensitizers of U-87 MG and T 98 cells to TMZ. In fact, a 16-fold lower concentration of TMZ (100 µM) was needed for significant cytotoxicity in U-87 MG cells co-exposed to synthetic Kalata B (0.5 µM). Similarly, a 15-fold lower concentration of TMZ (75 µM) was required for a significant reduction in cell viability in T 98 cells co-exposed to synthetic Kalata B1 (0.25 µM). Kalata B1 remained stable in human serum stability assays. The data support the assertion that cyclotides may chemosensitize glioblastoma cells to TMZ.more » « less
