Biophysical Society Thematic Meeting | Singapore

Mechanobiology of Disease

Poster Abstracts

64-POS Board 64 Ligand-Activated Epha2 Transport as Marker for Cancer Progression and Population Heterogeneity Andrea Ravasio 1 , Bakya Arasi 1 , Myint Z. Myaing 1 , Shumei Chia 2 , Vin Y. Chung 3 , Hui Ting Ong 1 , Ruby Yun-Ju Huang 3,4 , Ramanuj DasGupta 2 , Jay T. Groves 1,5,6 , Virgile Viasnoff 1,7,8 . 1 National University of Singapore, Singapore, Singapore, 2 Genome Institute of Singapore, A- STAR, Singapore, Singapore, 3 National University of Singapore, Singapore, Singapore, 4 National University Health System, Singapore, Singapore, 5 University of California, Berkeley, CA, USA, 6 University of California, Berkeley, CA, USA, 7 Centre National de la Recherche Scientifique, Singapore, Singapore, 8 National University of Singapore, Singapore, Singapore. Evolution of cancer into heterogeneous subclones is due to somatic mutations, epigenetic adaptations and selective pressure, leading to phenotypic differences, that result in different EMT states, migration capacity and, thus metastatic potential. Resistant subclones survive therapeutic intervention giving rise to recurrence of the disease. Here, we employ an assay to access the metastatic potential of cancer cells by their phenotypic ability to cluster EphA2 receptor upon ligand activation. Carcinoma cell lines from different organs, different EMT state and migratory capacity were seeded onto fluid lipid bilayers presenting the ligand - ephrinA1. Following activation of the receptor by the ligand, signalling cascades trigger a cytoskeleton-dependent clustering of the receptor. Using this assay, we could discriminate the degree of receptor clustering in single cancer cells and we found that it correlates with the EMT state and migration potential of the cells. Analysis of population distribution showed that fast migratory mesenchymal-transformed cell lines had a larger spread of the clustering values, suggesting for a greater heterogeneity within their population. To further test the correlation between migration speed and EphA2 clustering, we devised an assay to separate subpopulations of cells for their migration speed and persistence. Fast migratory cells - potentially more invasive – proved to have higher EphA2 clustering as compared to slower ones. Finally, to test the possible application of our assay as screening tool for the invasion potential of cancer cells and their population heterogeneity, we compared cell derived from biopsies from primary and secondary tumours. Cells from secondary tumour had higher EphA2 clustering as compared to primary ones. In summary, we showed that EphA2 receptor clustering proved to be a potential tool to rapidly assess metastatic potential of cancer cells and phenotypic subclonal differences in their population.

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