Our work focuses on the application of novel imaging modalities and on the development of radiation delivery methods. Both of these are dependent on a range of interrelated technologies.
Preclinical image-guided ionising radiation delivery systems are being developed, mimicking increasingly accurate patient radiotherapy. Numerous associated technical problems relate to dose delivery to small tissue volumes that ‘move’ due to breathing. We have developed sensors of this motion, coupled to very fast radiation beam gating. The accuracy of the radiation delivery critically depends on the quality of target imaging; conventional methods of cone beam CT are being complemented by optical fluorescence, ultrasound and other imaging techniques.
Fluorescence optical image guidance has also been developed for use during human surgery (Figure 1). Here we exploit the near infrared region of the optical spectrum (650-950 nm) to allow real-time imaging at tissue depths of <20 mm. This has been applied to lymph node imaging. An exciting new development is molecular optical imaging of prostate tumours to ensure that the surgeon is able to perform correct excision of extra-prostatic tumour tissue.
Time-resolved fluorescence microscopy techniques have been developed and enhanced over many years. Once excited by a light pulse, a fluorophore carries on emitting fluorescence light for a few nanoseconds. The kinetics of this process inform on resonance energy transfer between suitably chosen fluorophores tagged to proteins of interest (Főrster Resonance Energy Transfer, FRET). This is strongly dependent on the inter-fluorophore distance and the method can be used as a molecular ruler, capable of measuring distances of 1-10 nm, way below any competing methods. We have developed medium throughput, high content automated microscopy platforms to allow protein interaction screening of patient biopsies (Figure 2). The aim here is to determine which drugs are likely to be effective at treating the cancer.
We have also developed a unique system, based around an in-house 6 MeV electron linear accelerator coupled to a robot and fluorescence microscopy, to study radiation-induced cell DNA repair kinetics using high resolution time-lapse imaging. (Figure 3). We can resolve double strand breaks formed within seconds and are able to follow the temporal evolution of the repair of individual breaks.
Figure 1: Right: Near infrared fluorescence image guidance system developed by the group used during surgery at the Churchill Hospital. Left: Sentinel node removal during endometrial cancer laparoscopic surgery using our guidance system.
Figure 2: Typical images of fluorescence intensity (left) and pseudo-coloured image (right) of interacting fractions between specific proteins in a patient breast tumour tissue slice (collaboration T Ng and T Coolen, King’s College, London.
Figure 3: the 6 MeV accelerator.
Boris Vojnovic is Professor of Biophysics and has been the head of the Advanced Technology Development Group at the Oxford Institute for Radiation Oncology and Biology within the Department of Oncology since 2007. He held a similar position at the Gray Institute at Mount Vernon Hospital and has over 30 years’ experience in developing fast kinetic spectrophotometry techniques, fluorescence–based oxygen sensors, a range of accelerators and radiation sources applicable to radiobiology studies and numerous other biomedical instrumentation systems. His current interests include the application of fluorescence image-guidance techniques used during human surgery, in optimising preclinical radiation delivery systems and on the application of advanced fluorescence microscopy techniques in biomedicine.
Weitsman, G., Lawler, K., Shamil, E., Barrett, J., Barber, P.R., Kelleher, M.T., Festy, F., Patel, G., Fruhwirth, G., Huang, L., Tullis, I.D.C., Woodman, N., Ofo, E., Ameer-Beg, S.M., Irshad, S., Condeelis, J., Gillett, C.E., Ellis, P.A., Vojnovic, B., Coolen, A.C.C., Ng, T. “Imaging tumor heterogeneity of the consequences of a PKCα-substrate interaction in breast cancer patients,” (2014), Biochemical Society Transactions. 42, pt 6, 1498–1505; doi:10.1042/BST20140165
Liu, S., Zheng, Y., Volpi, D., El-Kasti, M., Klotz, D., Tullis, I.D.C., Henricks, A., Campo, L., Myers. K., Laios, A., Thomas, P., Ng, T., Dhar, S., Becker, C., Vojnovic, B., Ahmed, A.A. “Towards operative in vivo fluorescence imaging of c-Metproto-oncogene for personalization of therapy in ovarian cancer,” (2014) Cancer. Sep 10. doi: 10.1002/cncr.29029. [Epub ahead of print].
Volpi, D., Tullis I.D.C., Laios, A., Pathiraja P. N. J., Haldar K., Ahmed, A.A., and Vojnovic, B. “A novel multiwavelength fluorescence image-guided surgery imaging system,” (2014) Proceedings of SPIE, 8935, 89350G-89350G-9.
Tao, J., Castel, P., Radosevic-Robin, N., Elkabets, M., Auricchio, N., Aceto, N., Weitsman, G., Barber, P.R., Vojnovic, B., Ellis, H., Morse, N., Viola-Villegas, N.T., Bosch Campos, A., Juric, D., Hazra, S., Singh, S., Kim, P., Bergamaschi, A., Maheswaran, S., Ng, T., Penault-Llorca, F., Lewis, J.S., Carey, L.A., Perou, C.M., Baselga, J., and Scaltriti, M. “Antagonism of EGFR and HER3 Enhances the Response to Inhibitors of the PI3K-Akt Pathway in Triple-Negative Breast Cancer,” (2014) Science Signalling, 7, 318, ra29. [doi: 10.1126/scisignal.2005125] .
Kavanagh, A., Olivo, A., Speller, R., Vojnovic, B. “Feasibility testing of a pre-clinical coded aperture phase contrast imaging configuration using a simple fast Monte Carlo simulator,” (2013) Biomedical Optics Express. 5(1), 93 – 105. doi: 10.1364/BOE.5.000093. PMID 24466479.
Barber, P.R., Tullis, I.D.C., Pierce, G.P., Newman, R.G., Prentice, J., Rowley, M., Matthews, D.R., Ameer-Beg, S.M., Vojnovic, B. “The Gray Institute ‘Open’ High-Content, Fluorescence Lifetime Microscopes,” (2013). Journal of Microscopy, 251, (2), 154-167. PMID: 23772985
Peach, K.J., Aslaninejad, M., Barlow, R.J., Beard, C.D., Bliss, N., Cobb, J.H., Easton, M.J., Edgecock, T.R., Fenning, R., Gardner, I.S.K., Hill, M.A., Owen, H.L., Johnstone, C.J., Jones, B., Jones, T., Kelliher, D.J., Khan, A., Machida, S., McIntosh, P.A., Pattalwar, S., Pasternak, J., Pozimski, J., Prior, C.R., Rochford, J., Rogers, C.T., Seviour, R., Sheehy, S.L., Smith, S.L., Strachan, J., Tygier, S., Vojnovic, B., Wilson, P., Witte, H., Yokoi, T. “Conceptual design of a non-scaling fixed field alternating gradient accelerator for protons and carbon ions for charged particle therapy,” (2013) Physical Review ST Accelerators and Beams, 16, 030101-1-34.
Merchant, M.J., Jeynes, J.C.G., Grime, G.W., Palitsin, V., Tullis, I.D.C., Barber, P.R., Vojnovic, B., Webb., R.P., Kirkby, K.J. “A focused scanning vertical nanobeam for charged particle irradiation of living cells with single counted particles,” (2012) Radiation Research 178, 182-190.
Matthews, D.R., Fruhwirth, G.O, Weitsman, G.E., Carlin, L., Ofo, E., Keppler, M., Barber, P.R., Tullis, I., Vojnovic, B., Ng, T., and Ameer-Beg, S.M. “A Multi-Functional Imaging Approach to High-Content Protein Interaction Screening,” (2012) PLOS ONE, 7(4). PMID 22506000. doi: 10.1371/journal.pone.0033231
Mandeville, H.C., Ng, Q.S., Daley, F.M., Barber, P.R., Pierce, G., Finch, J., Burke, M., Bell, M.B., Townsend, E.R., Kozarski, R., Vojnovic, B., Hoskin, P.J., and Goh, V. “Operable Non-Small Cell Lung Cancer: Correlation of Volumetric Helical Dynamic Contrast-Enhanced CT Parameters with Immuno-histochemical Markers of Tumor Hypoxia,” (2012) Radiology, 264(2), 581-9; doi:10.1148/radiol.12111505. Epub 2012 Jun 14.
Wilson, P., Jones, B., Yokoi, T., Hill, M., and Vojnovic, B. “Revisiting the Ultra-High Dose Rate Effect: Implications for Charged Particle Radiotherapy Using Protons and Light Ions,” (2012) The British Journal of Radiology, 85(1018): e933–e939; doi: 10.1259/bjr/17827549; PMCID: PMC3474025. PMID 22496068.
Baker, M., Robinson, S.D., Lechertier, T., Barber, P.R., Tavora, B., D’Amico, G., Jones, D.T., Vojnovic, B., and Hodivala-Dilke, K. “Use of the mouse aortic ring assay to study angiogenesis,” (2012) Nature Protocols, 7, 89-104.
Waterhouse, B.R., Gijsen, M., Barber, P.R., Tullis, I.D.C., Vojnovic, B., and Kong, A. "Assessment of EGFR/HER2 dimerization by FRET-FLIM utilizing Alexa-conjugated secondary antibodies in relation to targeted therapies in cancers," (2011) Oncotarget 2, 728-736. PMID 21908901
Carlin, L.M., Evans, R., Milewicz, H., Fernandes, L., Matthews, D.R., Perani, M., Levitt, J., Keppler, M.D., Monypenny, J., Coolen, T., Barber, P.R., Vojnovic, B., Suhling, K., Fraternali, F., Ameer-Beg, S., Parker, P. J., Thomas, N.S.B., and Ng, T. “A targeted siRNA screen identifies regulators of Cdc42 activity at the natural killer cell immunological synapse,” (2011) Science Signaling. 4:201, ra81. PMID 22126964.
Patel, G.S., Kiuchi, T., Fruhwirth, G., Ofo, E., Kelleher, M., Shamil, E., Zhang, R., Selvin, P.R., Keppler, M., Santis, G., Spicer, J., Woodman, N., Gillett, C.E., Lawler, K., Coolen, A., Barber, P.R., Vojnovic, B., Kéri, G., Schaeffter, T., O’Doherty, M.J., Tutt, A., Ellis, P.A., and Ng, T. “The challenges of integrating molecular imaging into the optimization of cancer therapy,” (2011) Integrative Biology 3: 603-631 doi: 10.1039/C0IB00131G.
Cornelissen, B., Darbar, S., Hernandez, R., Kersemans, V., Tullis, I., Barber, P.R., Vojnovic, B., Vallis, K.A. “HER2 blockade and prenyltransferase inhibition alter EGF/EGFR trafficking and enhance 111In-DTPA-EGF Auger-electron radiation therapy,” (2011) Journal of Nuclear Medicine 52, 776 -783.
Fruhwirth, G., Fernandes, L., Weitsman, G., Patel, G., Kelleher, M., Lawler, K., Brock, A., Poland, S. Matthews, D., Keri, G., Barber, P., Vojnovic, B., Ameer-Beg, S., Coolen, A., Fraternali, F., and Ng, T. “How Förster Resonance Energy Transfer Imaging Improves the Understanding of Protein Interaction Networks in Cancer Biology,” (2011) ChemPhysChem. 12: 442-461. PMID: 21328516.
Matthews, D., Carlin, L., Ofo, E., Barber, P., Vojnovic, B., Irving, M., Ng, T. and Ameer-Beg, S. “Time-lapse FRET Microscopy using Fluorescence Anisotropy,” (2010) Journal of Microscopy 237, 1, 51-62 PMID: 20055918.
Kelleher, M., Fruhwirth, G., Patel, G., Ofo, E., Festy, F., Barber, P., Ameer-Beg, S., Vojnovic, B., Gillett, C., Coolen, A., Kéri, G., Ellis, P., and Ng, T. “The Potential of Optical Proteomic Technologies to Individualize Prognosis and Guide Rational Treatment for Cancer Patients,” (2009) Targeted Oncology, 4, 3, 235-252; doi: 10.1007/s11523-009-0116-y. PMID: 19756916.
Makrogianneli, K., Carlin, L.M., Keppler, M.D., Coolen, A.C., Ameer-Beg, S., Barber, P., Vojnovic, B., and Ng, T. “Integrating Receptor Signal Inputs That Influence Small Rho GTPase Activation Dynamics at the Immunological Synapse,” (2009) Molecular and Cellular Biology 29, 2997-3006 doi:10.1128/MCB.01008-08. PMID: 19307303.
Barber, P.R., Ameer-Beg, S.M., Gilbey, J., Carlin, L.M., Keppler, M.D., Ng, T.C., Vojnovic, B. “Multiphoton time-domain FLIM: Practical application to protein-protein interactions using global analysis,” (2009) Journal of the Royal Society Interface 6, S93-S105. (doi:10.1098/rsif.2008.0451.focus).
Tozer, G.M., Kanthou, C., Lewis, G., Prise, V.E., Vojnovic B., and Hill, S.A. “Tumour vascular disrupting agents: combating treatment resistance,” (2008) British Journal of Radiology, 81 S12-S20.
Barber, P.R., Pierce, G.P., Ameer-Beg, S.M., Matthews, D.R., Carlin, L.M., Keppler, M., Festy, F., Gillett, C., Springall, R., Ng, T.C., and Vojnovic, B. “Towards High-throughput FLIM for Protein-protein Interaction Screening of Live Cells and Tissue Microarrays,” (2008) In Biomedical Imaging: From Nano to Macro, 2008, ISBI 2008. 5th IEEE International Symposium 356-359.
Michette, A., Button, T., Dunare, C., Feldman, C., Folkard, M., Hart, D., McFaul, C., Morrison, G.R., Parkes, W., Pfauntsch, S., Powell, A.K., Rodriguez-Sanmartin, D., Sahraei, S., Stevenson, T., Vojnovic, B., Willingale, R. and Zhang, D. “Active micro-structured arrays for X-ray optics,” (2007) Advances in X-Ray/EUV Optics and Components II, Proceedings of SPIE 6705 670502.
Matthews, D., Summers, H., Njoh, K., Chappell, S., Errington, R., Smith, P., Pope, I., Barber, P., Vojnovic, B., Ameer-Beg, S. “A fluorescence biochip with a plasmon active surface,” (2007) Proceedings of SPIE, Volume 6450, 645006; doi:10.1117/12.698948.
Njoh, K., Smith, P.J., Chappell, S.C., Summers, H.D., Matthews, D., Morris, D., Goater, A., Burt, J., Pope, I., Vojnovic, B., Ameer-Beg, S., and Errington, R. J. “Live Cell Tracking on an Optical Biochip Platform,” (2007) Proceedings of SPIE, 6441, 64410X; doi:10.1117/12.698935.
Prag, S., Parsons, M., Keppler, M.D., Ameer-Beg, S.M., Barber, P., Hunt, J., Beavil, A.J., Calvert, R. Arpin, M., Vojnovic, B. and Ng, T. “Activated Ezrin Promotes Cell Migration through Recruitment of the GEF Dbl to Lipid Rafts and Preferential Downstream Activation of Cdc42,” (2007) Molecular Biology of the Cell, 18, 2935–2948. PMID: 17538024.