Periodic Report Summary - LSC CLL (Leukemic Stem Cells in Chronic Lymphocytic Leukemia) We obtained the following results:1) identified TGFßRIII as a novel marker for understanding CLL biology, demonstrating that the small portion of the clone bearing the receptor on surface membrane has high CXCR4 levels thus is likely attempting to re-enter a solid lymphoid tissue;2) identified a large panel of proteins highly correlating with in vivo measured cell proliferation;3) demonstrated the presence of miR-126 in CLL clones; its possible role has to be elucidated enlarging the number of samples studied;4) prepared the needs for beginning an in vivo study of cell kinetics in cancer in an Institution that never has performed this kind of studies