The expression of survivin and livin is upregulated in RRCLs. (A) Western blot analysis indicated that the IAPs livin and survivin were upregulated in the RRCLs (Raji 2R, Raji 4RH, and RL 4RH). The expression of cIAP1 and XIAP was moderately increased, whereas no change was observed in the level of cIAP2 between RRCLs and sensitive parent cell lines. (B) Quantitative PCR results demonstrate an increase in expression of the Birc5 and Birc7 genes, which encode the survivin and livin proteins, respectively, in the RRCLs Raji 4RH and RL 4RH compared with rituximab-sensitive control cell lines.