Intravital imaging in the study of tumor microenvironment and its role in tumor growth.

Abstract

Tumor growth is a dynamic process which involves cancer cell interactions with its stromal components: extracellular matrix, vasculature, lymphatics and a number of non-cancerous host cells such as cells of immune system or fibroblasts. These components are known to contribute to tumor malignancy and have thus become a relevant subject of many fundamental and clinical studies. Intravital imaging is a technology which has undergone considerable development in past decades. Improvements not only in picture resolution but also implementation of techniques lowering tissue phototoxicity and improving tissue access have made longitudinal studies on in vivo subjects in physiologically plausible setups possible. Using intravital microscopy it was possible to gain information on a number of processes relevant to tumor progression such as motility of distinct cell types at different tumor regions and at varying pharmacological conditions, kinetics of tumor cell killing, angiogenesis and vasculature functionality, or protease activity and metabolism. The direct observation of intact tumors as enabled by this approach provides vital information for the understanding of cancer progression as well as a possibility of discovery of anti-cancer therapeutic targets.