HMVECs were treated with vehicle or the indicated concentrations of Stx for 6 or 24 hours. Cellular ribosomes were fractionated based on density into 20 fractions, and RNA was purified from each fraction. mRNA levels were quantitated by qRT-PCR, normalized for luciferase mRNA, and shown relative to vehicle fraction no. 1. 80S refers to 80S ribosome. (A) CXCR4, (B) CXCR7, (C) SDF1, and (D) cyclophilin A. A representative experiment is shown.