UCL Cancer Institute Multidisciplinary Seminar Series

The UCL Cancer Institute Multidisciplinary Seminar Series highlights research from disciplines across UCL. The monthly seminars aim to present new and exciting work to Cancer Institute researchers and to forge collaborations across different disciplines in UCL.

Professor Tony Sinkus 'Imaging Tissue Biomechanics'

Alterations of tissues’ biomechanics are intimately linked to pathological developments, hence the importance of manual palpation in many domains such as breast cancer and prostate cancer. MR-elastography (MRE) offers a unique way to non-invasively explore tissue mechanics and tissue rheology and thereby provide quantification in absolute numbers. Tissue rheology provides insight into pathological processes which can be explored for characterization of tumours, staging of diffuse diseases such as liver fibrosis, but also quantification of response to therapy. MRE is based on the idea to visualize the propagation of mechanical shear waves at the cm wavelength via MRI and infer from the waves’ amplitude and phase the underlying biomechanical properties. Examples for liver fibrosis and liver/breast cancer will be given. As tissue organization is hierarchical – similar to anomalous diffusion in tissue – wave propagation in tissue also follows not a simple propagation model. This complexity - expressed in power-law dispersion behaviour - can be utilized to infer further structural information for disease characterization. The fractal organization of microvasculature opens another opportunity for MRE: sensing blood vessel architecture via multiple reflections of shear waves. This enables – similar to DWI – extending the resolution of MRE beyond the image resolution. The impact of local changes in blood volume/flow on apparent biomechanics will be discussed in the context of functional processes in the human brain. Finally, preliminary results will be presented indicting that metastatic behaviour can be manipulated via locally focussed shear waves.

Professor Tony Ng 'Tracking tumour evolution by imaging tissue / exosome-based oncogenic rewiring'

Originally trained as an HIV physician, Tony Ng, MD, PhD (Kings College London; University College London Comprehensive Cancer Imaging Centre (CCIC), UK) will discuss the role of HER pathway rewiring in cancer.  HER1 (EGFR), HER2 and HER3 are druggable targets in many tumour groups (currently being investigated in CCIC are breast, prostate, head and neck, lung and colorectal cancers).  Targeting of the HER molecules can be problematic however, because the four HER/ErbB family members are able to reconfigure into various heterodimers and reactivate the HER signaling pathway, conferring resistance to HER-targeting therapy.  Fluorescence Lifetime Imaging (FLIM) probes energy transfer between donor and receptor fluorophore-labeled antibodies when under 10nm apart.  FLIM was used to examine the levels of EGFR:HER3 heterodimers in tumor tissues from triple negative breast cancer patients pre vs. post neoadjuvant treatment with cetuximab/panitumumab.  EGFR:HER3 heterodimers were not observed prior to treatment, but were highly induced after 6 cycles of cetuximab in >70% of patients with residual tumor burden.  In order to non-invasively monitor HER pathway rewiring, a method was developed to perform FLIM in tumor-derived exosomes harvested from blood.  The heterogeneous expression of exosomal HER/c-Met as well as their dimer formation are being exploited as an exploratory predictive marker in a pan-European interventional cancer trial. The translational vision of combining whole body immuno-PET imaging of HER/c-Met and exosomal receptor rewiring information, in correct stratification of patient treatment, will be discussed.

A light lunch will be provided after the seminar

Location

UCL Cancer Institute
Courtyard Café
Paul O'Gorman Building 
72 Huntley Street
London, WC1E 6DD

UCL Hospitals Biomedical Research Centre