Abstract 1143: The circulating tumor cell (CTC) microenvironment visualized by color coded imaging

Abstract

Abstract Background/Aim: An important question is whether cancer cells circulate with stromal cells. A color-coded mouse model of metastatic lymphoma was utilized to investigate the microenvironment of CTC clusters using fluorescent-protein imaging. Materials and Methods: EL-4 mouse lymphoma cells expressing red fluorescent protein (RFP) were injected into the spleen of transgenic C57BL6-green fluorescent protein (GFP) mice. The cellular composition of CTC clusters both in heart blood and portal blood was imaged with confocal microscopy. Results: CTC clusters comprised 8.8% of CTCs determined by color-coded imaging. Heterotypic CTC clusters containing other types of cells were distinguishable from homotypic CTCs. Heterotypic CTC clusters comprising cancer cells and fibroblasts were more rare than homotypic ones. Heterotypic CTC clusters with fibroblasts were observed only in portal blood, not in heart blood. Conclusion: CTCs can form clusters, which may contain fibroblast or other stromal cells that may play a role in promoting CTC metastasis. Citation Format: Atsushi Suetsugu, Tomoyuki Satake, Miki Nakamura, Masahito Shimizu, Shigetoyo Saji, Hisataka Moriwaki, Robert M. Hoffman. The circulating tumor cell (CTC) microenvironment visualized by color coded imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1143.