Quantitation of macropinocytosis in glioblastoma based on high-content analysis.

BACKGROUND:Macropinocytosis is a pathway utilized for the internalization of extracellular fluid, albumin and dissolved molecules. Assessing macropinocytosis has been challenging in the past because the combination of manual acquisition and visual evaluation of images is laborious, making this type of assessment difficult for high-throughput applications. Therefore, there is a need to develop sensitive and specific macropinocytosis evaluation methods. METHODS:This paper proposed a quantitative and time-saving method for macropinocytosis detection based on high-content analysis (HCA). Additionally, cell proliferation was evaluated using CCK8 test. RESULTS:The term "macropinosome index" was defined to estimate macropinocytosis and allow comparisons between different cell lines and treatments. Furthermore, we demonstrated that macropinocytosis can promote glioblastoma (GBM) cell survival under L-glutamine (L-Gln)-deficient conditions that resemble the tumour microenvironment. CONCLUSIONS:HCA represents a novel, nonsubjective and high-throughput assay for macropinocytosis assessment. In addition, L-Gln deprivation increased the macropinosome index in GBM cells, suggesting that this process may be used to design GBM therapies. AVAILABILITY OF DATA AND MATERIALS:The datasets supporting the conclusions of this article are included within the article and its supplementary materials.