ITGA4 and B-cell chronic lymphocytic leukemia: The virtual absence of nonresponder cases in this CLL cohort may be explained by the correlation of high CD49d expression with the presence of other negative prognostic factors, such an unmutated (UM) immunoglobulin heavy chain variable (IGHV) mutational status and TP53 disruption (Table S1), which have previously been shown to be associated with BCR responsiveness (Mockridge et al., 2007; Apollonio et al., 2013).