Quantitative in vivo imaging of the effects of inhibiting integrin signaling via Src and FAK on cancer cell movement: effects on E-cadherin dynamics.
Most cancer-related deaths are due to the development of metastatic disease, and several new molecularly targeted agents in clinical development have the potential to prevent disease progression. However, it remains difficult to assess the efficacy of antimetastatic agents in the clinical setting, and an increased understanding of how such agents work at different stages of the metastatic cascade is important in guiding their clinical use. We used optical window chambers combined with photobleaching, photoactivation, and photoswitching to quantitatively measure (a) tumor cell movement and proliferation by tracking small groups of cells in the context of the whole tumor, and (b) E-cadherin molecular dynamics in vivo following perturbation of integrin signaling by inhibiting focal adhesion kinase (FAK) and Src. We show that inhibition of Src and FAK suppresses E-cadherin-dependent collective cell movement in a complex three-dimensional tumor environment, and modulates cell-cell adhesion strength and endocytosis in vitro. This shows a novel role for integrin signaling in the regulation of E-cadherin internalization, which is linked to regulation of collective cancer cell movement. This work highlights the power of fluorescent, direct, in vivo imaging approaches in the preclinical evaluation of chemotherapeutic agents, and shows that inhibition of the Src/FAK signaling axis may provide a strategy to prevent tumor cell spread by deregulating E-cadherin-mediated cell-cell adhesions.
Edinburgh Cancer Research Centre, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, United Kingdom.
Marta
M
Canel
Alan
A
Serrels
Derek
D
Miller
Paul
P
Timpson
Bryan
B
Serrels
Margaret C
MC
Frame
Valerie G
VG
Brunton
D000818:Animals; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002448:Cell Adhesion; D002450:Cell Communication; D045744:Cell Line, Tumor; D002465:Cell Movement; D049109:Cell Proliferation; D004705:Endocytosis; D036681:Fluorescence Recovery After Photobleaching / Q000379:methods; D051416:Focal Adhesion Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D015151:Immunoblotting; D019012:Integrin beta1 / Q000235:genetics / Q000378:metabolism; D016023:Integrins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D056004:Molecular Dynamics Simulation; D009369:Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D034622:RNA Interference; D015398:Signal Transduction; D019061:src-Family Kinases / Q000235:genetics / Q000378:metabolism*
D015820:Cadherins; D019012:Integrin beta1; D016023:Integrins; D051416:Focal Adhesion Protein-Tyrosine Kinases; D019061:src-Family Kinases