Out of five different plasmids encoding shRNAs to downregulate CAT-1 upon lentiviral transduction, plasmid pLKO.1-puro_SLC7A1-5 maximally suppressed CAT-1 mRNA in HG3 CLL cells and was used for all further experiments. The gene discussed is SLC7A1; the disease is B-cell chronic lymphocytic leukemia.