Farahani et al. showed that CLL exosomes encapsulate an abundant amount of microRNA-202-3p that, once integrated in stromal HS-5 cell lines, enhanced their proliferation and decreased apoptosis by inducing the expression of genes such as c-fos and ataxia telangiectasia mutated (ATM) (144). This evidence concerns the gene ATM and B-cell chronic lymphocytic leukemia.