Fig. 8: Collective migration of COL1A1 enriched oncostreams contributes to malignant glioma behavior at the tumor invasive border.

A Experimental setup and location of imaging of tumor borders using td/mtTomato mice (Movie #5) (Created in BioRender.com). B Representative time-lapse scanning confocal image of glioma cells at the tumor border and subdivision into different zones. The image shows tumor cells (green) and brain parenchyma (red). C Preferred direction of cells within different zones superimposed onto a representative time lapse-image. D Histogram of speed distribution and mean speed (µm/h) of Zones A, B, C, and D. E Angle Velocity distribution (θ) analysis performed by zones. Plot shows overall direction and magnitude of cell movement. F Likelihood analysis of the dynamic patterns at the tumor border. Graph of density estimation ρ flock (red), ρ stream (yellow), and ρ swarm (blue). Black line (data) uses a non-parametric estimation. AW:0 or AW:1. G Immunofluorescence analysis of GFP+ cells in Genetically Engineer Mouse Models of glioma controls NPA (n = 6), and NPAshCOL1A1 (n = 5). GFP is shown in green (Alexa 488) and nuclei in blue (DAPI). Dotted lines show tumor borders. Stars show tumor invasive patterns. Notice the absence of collective invasion patterns in NPAshCOL1A1. Scale bar: main(left) 100 μm, inset(right) 50 μm. H Tumor borders were analyzed using the Allen-Cahn equation. Images were split into two values (−1 and +1) representing the inside and outside of the tumor. Illustration of the sinuosity of a curve: it is defined as the ratio between the length of the curve L and the distance between the two extreme points. I Sinuosity of the border for all experiments. NPA: n = 6 and NPAshCOL1A1: n = 5 tumors for each experimental condition were used for the analysis. We detected a decrease of the sinuosity in COL1A1 knockdown tumors. t-test unequal variance, *p = 0.0297. Center of the boxplot is the median value, upper bound of the boxplot is the Q3 (75th percentile), the lower bound of the boxplot is the Q1 (25th percentile), the upper whiskers is the maximum value of the data (within 1.5 times the interquartile range over the 75th percentile), and the lower whisker is the minimum value of the data (within 1.5 times the interquartile range under the 25th percentile).