Fig. 3. XG1LenRes demonstrated altered CD147 expression and impaired lenalidomide-mediated downregulation of IRF4 (truncated form).

a Immunoblotting of XG1 and XG1LenRes demonstrated that XG1LenRes has normal CRBN expression and has an altered CD147 expression compared with XG1. b Introduction of exogenous CRBN into XG1LenRes did not restore its sensitivity. c In addition to a full-length (f) IRF4, a short (s) IRF4 protein was detected from both XG1 and XG1LenRes. Upon lenalidomide treatment, shorted IRF4 in XG1LenRes was not downregulated as well as in XG1. d Mate pair sequencing data suggested that the IRF4 gene in both XG1 and XG1LenRes has an inversion mutation, which is likely to produce a short C-terminal-truncated IRF4 protein