Phenotypic effect of TβRIII knockdown in MSL cells. A-C) Cells were plated around magnetic stencils. After cells had adhered the magnetic stencils were removed and migration assay was monitored for 24 hours. Bar graphs represent percentages of closure for each MSL cell line with TβRIII-KD in comparison to control with or without TGF-β1 and TGF-β2 treatment; graph bars represent the mean of three replicates with SEM error bars (**P = 0.001, ***P <0.0001 for a two-tailed Student’s t-test). D-F) Number of MSL cells that invaded through matrigel pre-coated transwells with or without 24 hour pre-treatment of cells with TGF-β1 and TGF-β2 ligands (***P <0.0001 for a two-tailed Student’s t-test). G) Representative 10x images of SUM159 controls versus TβRIII-KD cells embedded in three-dimensional matrigel culture. Scale bar: 300 μm. H) Quantification of SUM159 three-dimensional matrigel culture; bar graph represent tumor-sphere perimeter derived from mean of three replicates with SEM error bars (*P = 0.029 for a two-tailed Student’s t-test). MSL, mesenchymal stem-like; SEM, standard error of the mean; TGF-β, transforming growth factor beta; TβRIII-KD, type III transforming growth factor-beta receptor knockdown.