Receptor Tyrosine Kinases (RTKs) are clinically validated targets that can be blocked to enhance the efficacy of radiation therapy. However, the co-expression of multiple RTKs and other cell surface receptors limits this therapeutic approach. We have identified protein N-linked glycosylation (NLG) as a co-translational protein modification that can be targeted to reduce signaling of multiple over-expressed RTKs. NLG inhibition radiosensitizes cancer cells both in vitro and in vivo and research to optimize NLG inhibition is therefore required to advance this strategy to clinical trials. Based on our preliminry data, we hypothesize that discrete steps in the NLG biosynthetic machinery can be targeted to block RTK and cell surface receptor survival signaling and enhance radiation therapy. We have generated novel human cell models with NLG defects to address the role of glycosylation in mediating receptor signaling and sensitivity to ionizing radiation. We have also identified a pharmacologic strategy for blocking NLG in tumor cells. An additional component of these studies will evaluate NLG activity in xenograft tumor models of glioma using a bioluminescent molecular imaging platform. We plan to use these pre-clinical models to evaluate and test specific NLG enzymes as gene targets for therapeutic inhibition in combination with radiation therapy. This project will provide new insights into the contributions of NLG to cancer biology as well as provide therapeutic targets for enhancing radiation therapy in the treatment of malignant disease.

Public Health Relevance

The prognosis for malignant glioma is exceptionally poor and clinical trials have demonstrated that delivery of a systemic therapy concurrent with localized radiation increases local tumor control and improves patient survival. We have identified protein N-linked glycosylation as a novel cellular target for therapeutic inhibition, an approach that blocks cell surface receptor dependent survival signaling and enhances tumor cell radiosensitivity. Successful completion of the proposed research will therefore advance pre-clinical strategies for targeting N-linked glycosylation with the goal of enhancing the efficacy of radiation therapy in the treatment of malignant glioma.

National Institute of Health (NIH)
National Cancer Institute (NCI)
Research Project (R01)
Project #
Application #
Study Section
Radiation Therapeutics and Biology Study Section (RTB)
Program Officer
Ahmed, Mansoor M
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
Yale University
Schools of Medicine
New Haven
United States
Zip Code
Lopez Sambrooks, Cecilia; Baro, Marta; Quijano, Amanda et al. (2018) Oligosaccharyltransferase Inhibition Overcomes Therapeutic Resistance to EGFR Tyrosine Kinase Inhibitors. Cancer Res 78:5094-5106
Rinis, Natalia; Golden, Jennifer E; Marceau, Caleb D et al. (2018) Editing N-Glycan Site Occupancy with Small-Molecule Oligosaccharyltransferase Inhibitors. Cell Chem Biol 25:1231-1241.e4
Baro, Marta; Lopez Sambrooks, Cecilia; Quijano, Amanda et al. (2018) Oligosaccharyltransferase Inhibition Reduces Receptor Tyrosine Kinase Activation and Enhances Glioma Radiosensitivity. Clin Cancer Res :
Bennett, Daniel C; Cazet, Aurelie; Charest, Jon et al. (2018) MPDU1 regulates CEACAM1 and cell adhesion in vitro and in vivo. Glycoconj J 35:265-274
Puschnik, Andreas S; Marceau, Caleb D; Ooi, Yaw Shin et al. (2017) A Small-Molecule Oligosaccharyltransferase Inhibitor with Pan-flaviviral Activity. Cell Rep 21:3032-3039
Lopez-Sambrooks, Cecilia; Shrimal, Shiteshu; Khodier, Carol et al. (2016) Oligosaccharyltransferase inhibition induces senescence in RTK-driven tumor cells. Nat Chem Biol 12:1023-1030
Cazet, Aurélie; Charest, Jonathan; Bennett, Daniel C et al. (2014) Mannose phosphate isomerase regulates fibroblast growth factor receptor family signaling and glioma radiosensitivity. PLoS One 9:e110345