Exploring whether these time-dependent variations would translate into differences in IL-16 protein expression in MM cells, we next analyzed levels of intracellular IL-16 protein in 10 different MM cell lines and we found that in the case of 8 of these lines more than 90% of the cells were positive for intracellular IL-16 (Figure 1C) indicating a constitutive and homogenous protein expression of this cytokine in MM. This evidence concerns the gene IL16 and Miyoshi myopathy.