In vivo 3D profiling of site-specific human cancer cell morphotypes in zebrafish

Determining the influences of tissue microenvironment on cancer cell states in vivo remains a challenge. Segal et al. present a quantitative high-resolution imaging assay of single cancer cell morphology in zebrafish xenografts to probe functional adaptation to variable cell-extrinsic cues and molecular interventions. Tissue microenvironments affect the functional states of cancer cells, but determining these influences in vivo has remained a challenge. We present a quantitative high-resolution imaging assay of single cancer cells in zebrafish xenografts to probe functional adaptation to variable cell-extrinsic cues and molecular interventions. Using cell morphology as a surrogate readout of cell functional states, we examine environmental influences on the morphotype distribution of Ewing Sarcoma, a pediatric cancer associated with the oncogene EWSR1-FLI1 and whose plasticity is thought to determine disease outcome through non-genomic mechanisms. Computer vision analysis reveals systematic shifts in the distribution of 3D morphotypes as a function of cell type and seeding site, as well as tissue-specific cellular organizations that recapitulate those observed in human tumors. Reduced expression of the EWSR1-FLI1 protein product causes a shift to more protrusive cells and decreased tissue specificity of the morphotype distribution. Overall, this work establishes a framework for a statistically robust study of cancer cell plasticity in diverse tissue microenvironments.

Automated summary

This study presents a quantitative high-resolution imaging assay to investigate the functional adaptation of cancer cells to different cell-extrinsic cues and molecular interventions in zebrafish xenografts. The analysis reveals systematic shifts in the distribution of cancer cell morphotypes as influenced by the tissue microenvironment. The reduced expression of an oncogene product causes changes in cell morphology and tissue specificity.