Metastasis is a very complicated multi-step process and accounts for the low survival rate of the cancerous patients. To
metastasize, the malignant cells must detach from the primary tumor and migrate to secondary sites in the body through
either blood or lymph circulation. Macrophages appear to be directly involved in tumor progression and metastasis.
However, the role of macrophages in affecting cancer metastasis has not been fully elucidated. Here, we have utilized an
emerging technique, namely in vivo flow cytometry (IVFC) to study the depletion kinetics of circulating prostate cancer
cells in mice and how depletion of macrophages by the liposome-encapsulated clodronate affects the depletion kinetics.
Our results show different depletion kinetics of PC-3 cells between macrophage-deficient group and the control group.
The number of circulating tumor cells (CTCs) in macrophage-deficient group decreases in a slower manner compared to
the control mice group. The differences in depletion kinetics indicate that the absence of macrophages facilitates the stay
of prostate cancer cells in circulation. We speculate that macrophages might be able to arrest, phagocytose and digest
PC-3 cells. Therefore, the phagocytosis may mainly contribute to the depletion kinetic differences. The developed
methods here would be useful to study the relationship between macrophages and tumor metastasis in small animal
cancer model.© (2012) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Xiaojun Cui ; Jin Guo ; Zhengqin Gu and Xunbin Wei
"Studying the role of macrophages in circulating prostate cancer cells
by in vivo flow cytometry", Proc. SPIE 8553, Optics in Health Care and Biomedical Optics V, 85530W (December 11, 2012); doi:10.1117/12.2001640; http://dx.doi.org/10.1117/12.2001640