Reducing GGT7 expression increases GBM cell growthin vitro. (A) siRNA to GGT7 (siGGT7) reduced endogenous GGT7 protein expression compared with the siScram. GAPDH was used as a protein load control. Fold difference is represented below each blot. (B) Growth of U138 cells with reduced GGT7 expression under normal (10% serum) conditions. (C) Cell growth under low nutrient (1% serum) conditions. (D) Anchorage-independent growth assays were performed under normal and low nutrient conditions. *Denotes a statistically significant change, P < 0.05, measured by the Mann–Whitney U test.