Noninvasive Imaging: Brillouin Confocal Microscopy.

In the past decades, there has been increased awareness that mechanical properties of tissues and cells are closely associated with disease physiology and pathology. Recognizing this importance, Brillouin spectroscopy instrumentation, already utilized in physics and material science, has been adopted for cell and tissue biomechanics. For biomedical applications, progress of Brillouin spectrometer technology has been crucial, mainly improvement in the acquisition speed and combination with confocal microscopy, to enable measurement of material longitudinal modulus in three dimensions with high spatial resolution. Micron spatial resolution and high sensitivity allow mapping intracellular modulus and distinguishing between nuclear and cytoplasmic mechanical properties as well as detecting changes due to perturbations of individual cellular components. In cancer, environmental mechanical factors and intracellular mechanics are expected to play an integral role in cancer progression and treatment success. Brillouin confocal microscopy is appealing for many studies in cancer mechanobiology involving both primary tumors and metastatic dissemination. Specifically, Brillouin technology is suitable for experimental scenarios where noncontact mechanical measurements are required such as 3D tumor models, interactions with the extracellular matrix (ECM), investigation of nuclear mechanical properties, or analysis of cells within microfluidic chips.