In vivo measurement of gene expression, angiogenesis and physiological function in tumors using multiphoton laser scanning microscopy

Intravital microscopy coupled with chronic animal window models has provide d stunning insight into tumor pathophysiology, including gene expression, a ngiogenesis, cell adhesion and migration, vascular, interstitial and lympha tic transport, metabolic microenvironment and drug delivery. However, the f indings to date have been limited to the tumor surface (< 150 <mu>m). Here, we show that the multiphoton laser-scanning microscope can provide high th ree-dimensional resolution of gene expression and function in deeper region s of tumors. These insights could be critical to the development of novel t herapeutics that target not only the tumor surface, but also internal regio ns.