KD of miR-17∼92 in ALK(+) ALCL cell lines. (A) Diagram of the lentivirus construct expressing GFP and a sponge that has 7 tandem binding sites for each of the 4 miRNA families present in the miR-17∼92 cluster (targeting from 5′ to 3′, miR-17, miR-20, miR-18, miR-19, and miR-92). (B) Cell cycle analysis. (C) Apoptosis analysis in Karpas 299 after miR-17∼92 KD. (D) Relative expression of 2 representative miR17∼92 cluster members (miR-19a and miR-92) after treatment with Stattic for 12 hours (upper panel). pYSTAT3 levels after treatment with various concentrations of Stattic in ALCL cell lines (Karpas 299, JB6, L82). (E) Inhibitory concentration 50% (IC₅₀) for the STAT3 inhibitor Stattic in Karpas 299 cells (right panel) and combined effect of Stattic and miR-17∼92 inhibition in Karpas 299 (left panel). (F) Immunoblotting of PTEN, pYSTAT3, STAT3 (total), pAKT, and pRPS6 with or without miR-17∼92 KD. DMSO, dimethylsulfoxide.