Fig. 5
IMPACT overexpression confers GL261 glioma cells increased survival during tryptophan deprivation. a) Western blotting with indicated antibodies on GL261-wild-type and GL261-IMPACThigh lines cultured in standard media containing 50 μM tryptophan over a period of 8 days. Doubling time is shown as a mean ± SD. b) Fluorescence microscopy images (20x objective) of GL261-wild-type and GL261-IMPACThigh lines stained with fluorescein diacetate and propidium iodide after five days of culture in media containing tryptophan concentrations ranging from 2.5 μM to 50 μM. c) Metabolic activity of GL261-wild-type and GL261-IMPACThigh lines determined using the MTT assay. Bar heights and whiskers represent a mean ± SD of four replicates. Statistical significance was determined using Student’s t-test in Graphpad Prism v7.03. ***P < 0.001, **P < 0.01, ns P > 0.25