HMGB1 and B-cell chronic lymphocytic leukemia: Such signaling could occur by circulating DNA molecules binding to the receptor for advanced glycosylation end products (RAGE) on CLL cells, directly or in a complex with HMGB1 [30], or binding of DNA or DNA-HMGB1 complexes to smTLR9 on the small circulating subpopulation of CLL cells, since both soluble DNA and HMGB1 are abundant in the sera of CLL patients [31,32], and the CLL cells bearing smTLR9 express the CXCR4DimCD5Bright phenotype of the PF [31].