Cellular imaging and texture analysis distinguish differences in cellular dynamics in mouse brain tumors

Abstract

The heterogeneous tumor cell population and dynamic microenvironment within a tumor lead to regional variations in cell proliferation, migration, and differentiation. In this work, MRI and optical projection tomography were used to examine and compare the redistribution of a cellular label in two mouse glioma models. GL261 and 4C8 glioma cells labeled with iron oxide particles or with a fluorescent probe were injected into the brains of syngeneic mice and allowed to develop into ∼10-mm(3) tumors. Texture analysis was used to quantitatively describe and compare the label distribution patterns in the two tumor types. The label was seen to remain predominantly in the tumor core in GL261 tumors, but become more randomly distributed throughout the tumor volume in 4C8 tumors. Histologically, GL261 tumors displayed a more invasive, aggressive phenotype, although the distribution of mitotic cells in the two tumors was similar. The redistribution of a cellular label during tumor growth is characteristic of a tumor model. The label distribution map reflects more than simple differences in cell proliferation and is likely influenced by differences in the tumor microenvironment.