Fig. 4: HOXA4 expression is associated with increased drug sensitivity.

a Diagrammatic representation of the lentiviral construct used to transduce Raji and primary CLL cells. The SFFV promoter, HOXA4 gene, internal ribosomal entry site (IRES) and green fluorescent protein (GFP) gene are indicated. b–d Drug sensitivity of control (empty vector) and HOXA4-expressing transduced Raji cells in response to treatment with fludarabine (b), ibrutinib (c) and idelalisib (d). Apoptosis was measured 48 h after drug treatment by detection of Annexin V by flow cytometry. Mean values are displayed, with error bars indicating standard error of the mean. e Sensitivity of primary CLL cells transduced to express HOXA4 to fludarabine treatment (n = 3). Apoptosis was measured 48 h after drug treatment by detection of Annexin V by flow cytometry. Mean values are displayed, with error bars corresponding to standard error of the mean. Statistical significance is indicated (*P < 0.05; **P < 0.01; ***P < 0.005; ****P < 0.001).