Engineering a Glioblastoma-on-Chip to Decipher the Contribution of Blood-Tumor-Barrier in Chemoresistance

Glioblastoma multiforme (GBM) is the most common primary form of brain tumor and one of the deadliest human cancers. The median length of survival following diagnosis is 12 to 15 months, with less than 10% of people surviving longer than five years1. Conventional GBM chemotherapies are mostly designed to directly kill cancer cells, and the effectiveness is often compromised by their penetration through the brain-tumor-barrier (BTB).

Glioblastoma cells growing within the brain, frequently subvert the physiological function of the cerebrovascular tissue and turn the human blood-brain barrier (BBB) into an effective BTB capable of protecting the cancer mass from drugs and circulating immune cells. Despite being characterized as a disrupted vascular tissue2,3, the BTB retains critical aspects of the BBB including expression of active efflux transporters4 what seems a main factor determining suboptimal drug accumulation in brain tumors5–7. As such, the BTB is a well-renewed rate-limiting factors in clinically effective therapy.

Unfortunately, existing in vitro models of GBM including spheroids, the current state-of-the-art in modeling of GBM8, do not incorporate brain endothelial cells, nor other elements of the tumor microenvironment known to play a key role in mediating drug resistance in vivo. An in vitro model able to recapitulate the key features of the BTB and to predict drug efficacy, may open new opportunities for developing of novel therapies designed to target the tumoral microenvironment of GBM.

This project aims to establish an Organ-on-Chip9–11 model of the human BTB. We will use a 3D printing approach for generating a perfusable microtissue12 designed to closely mimic the anatomical structure of the human BBB. Stem cells derived brain cells will be obtained as previously described13,14 to build a vascularized microfluidic compartment, lined with endothelial cells directly interfaced with astrocytes and brain microglia cells all harbored in a biocompatible hydrogel. We will define optimal biochemical and biomechanical parameters, including hydrogel composition and vascular shear rate, for co-culturing of cancer cell lines of GBM together with stem-cell derived brain cells (Fig.1). Fluorescent microscopy will be used to assess the ability of this system to sustain cancer cell growth and to recapitulate the subversive events that lead to the formation of the BTB, including displacement of astrocytic end-feet15, loss of vascular barrier-function and the expression of active efflux pumps.

Diagram of the main elements of the glioblastoma BTB-on-chip

Fig.1 - Schematics displaying (on the top) the main elements used in this project to combine existing bioprinting methods and advanced cell culture techniques for developing a stem-cell derived in vitro model of GBM. The microenvironment of the bioprinted Chip (on the bottom) support the natural ability of cells to self-assembly into 3D structures and to further promote cell-cell interactions and formation of a vascularized cancer mass.

References

  1. Department of Neurosurgery, Jordan University Hospital and Medical School, University of Jordan, Amman, Jordan, Tamimi, A. F., Juweid, M., & Department of Radiology and Nuclear Medicine, Jordan University Hospital and Medical School, University of Jordan, Amman, Jordan. Epidemiology and Outcome of Glioblastoma. in Glioblastoma (eds. Department of Neurosurgery, University Hospitals Leuven, Leuven, Belgium & De Vleeschouwer, S.) 143–153 (Codon Publications, 2017). doi:10.15586/codon.glioblastoma.2017.ch8.
  2. Hirano, A. & Matsui, T. Vascular structures in brain tumors. Hum. Pathol. 6, 611–621 (1975).
  3. Bertossi, M., Virgintino, D., Maiorano, E., Occhiogrosso, M. & Roncali, L. Ultrastructural and Morphometric Investigation of Human Brain Capillaries in Normal and Peritumoral Tissues. Ultrastruct. Pathol. 21, 41–49 (1997).
  4. van Tellingen, O. et al. Overcoming the blood–brain tumor barrier for effective glioblastoma treatment. Drug Resist. Updat. 19, 1–12 (2015).
  5. Hobbs, S. K. et al. Regulation of transport pathways in tumor vessels: Role of tumor type and microenvironment. Proc. Natl. Acad. Sci. 95, 4607–4612 (1998).
  6. Monsky, W. L. et al. Role of host microenvironment in angiogenesis and microvascular functions in human breast cancer xenografts: mammary fat pad versus cranial tumors. Clin. Cancer Res. Off. J. Am. Assoc. Cancer Res. 8, 1008–1013 (2002).
  7. Sarkaria, J. N. et al. Is the blood–brain barrier really disrupted in all glioblastomas? A critical assessment of existing clinical data. Neuro-Oncol. 20, 184–191 (2018).
  8. Azzarelli, R. Organoid Models of Glioblastoma to Study Brain Tumor Stem Cells. Front. Cell Dev. Biol. 8, 220 (2020).
  9. Ingber, D. E. Reverse Engineering Human Pathophysiology with Organs-on-Chips. Cell 164, 1105–1109 (2016).
  10. Fabre, K. M., Livingston, C. & Tagle, D. A. Organs-on-chips (microphysiological systems): tools to expedite efficacy and toxicity testing in human tissue. Exp. Biol. Med. 239, 1073–1077 (2014).
  11. Barrile, R. et al. Organ-on-Chip Recapitulates Thrombosis Induced by an anti-CD154 Monoclonal Antibody: Translational Potential of Advanced Microengineered Systems. Clin. Pharmacol. Ther. 104, 1240–1248 (2018).
  12. Bersini, S. et al. Cell-microenvironment interactions and architectures in microvascular systems. Biotechnol. Adv. 34, 1113–1130 (2016).
  13. Lippmann, E. S. et al. Derivation of blood-brain barrier endothelial cells from human pluripotent stem cells. Nat. Biotechnol. 30, 783–791 (2012).
  14. Vatine, G. D. et al. Human iPSC-Derived Blood-Brain Barrier Chips Enable Disease Modeling and Personalized Medicine Applications. Cell Stem Cell 24, 995-1005.e6 (2019).
  15. Watkins, S. et al. Disruption of astrocyte–vascular coupling and the blood–brain barrier by invading glioma cells. Nat. Commun. 5, 4196 (2014).

Director

Headshot of Riccardo Barrile

Riccardo Barrile

Assistant Professor, CEAS - Biomedical Eng

554 Engineering Research Cntr

617-784-9530