imaging-flow-cytometry-based-analysis-cell-position-cell-cycle-3d

Imaging- and Flow Cytometry-based Analysis of Cell Position and the Cell Cycle in 3D Melanoma Spheroids

Three-dimensional (3D) tumor spheroids are utilized in cancer research as a more accurate model of the in vivo tumor microenvironment, compared to ...

The Centenary Institute

University of Sydney

Solid cancers are composed of heterogeneous zones containing proliferating and quiescent cells. Despite considerable insight into the molecular mechanisms underlying aberrant cell cycle progression, there is limited understanding of the relationship between the cell cycle on the one side, and melanoma cell motility, invasion, and drug sensitivity on the other side. Utilizing the fluorescent ubiquitination-based cell cycle indicator (FUCCI) to longitudinally monitor proliferation and migration of melanoma cells in 3D culture and in vivo, we found that invading melanoma cells cycle actively, while G1-arrested cells showed decreased invasion. Melanoma cells in a hypoxic environment or treated with mitogen-activated protein kinase pathway inhibitors remained G1-arrested for extended periods of time, with proliferation and invasion resuming after re-exposure to a more favorable environment. We challenge the idea that the invasive and proliferative capacity of melanoma cells are mutually exclusive and further demonstrate that a reversibly G1-arrested subpopulation survives in the presence of targeted therapies.

Real-time cell cycle imaging during melanoma growth, invasion, and drug response.

The 18-kDa mitochondrial translocator protein (TSPO) is known to be highly expressed in several types of cancer, including gliomas, whereas expression in normal brain is low. TSPO functions in glioma are still incompletely understood. The TSPO can be quantified pre-operatively with molecular imaging making it an ideal candidate for personalized treatment of patient with glioma. Studies have proposed to exploit the TSPO as a transporter of chemotherapics to selectively target tumour cells in the brain. Our studies proved that positron emission tomography (PET)-imaging can contribute to predict progression of patients with glioma and that molecular imaging with TSPO-specific ligands is suitable to stratify patients in view of TSPO-targeted treatment. Finally, we proved that TSPO in gliomas is predominantly expressed by tumour cells.

Andrea Anfosso

The Centenary Institute

Imaging- and Flow Cytometry-based Analysis of Cell Position and the Cell Cycle in 3D Melanoma Spheroids