JAK2 and B-cell chronic lymphocytic leukemia: Subsequently, we correlated STAT3 and JAK2 expression with the most relevant biological prognostic markers (e.g., cytogenetics abnormalities [20], Immunoglobulin Heavy Chain Variable region (IGHV) mutational status [21], and Integrated CLL Scoring System (ICSS score) [22], Figure S2), but no statistical differences were highlighted, suggesting that both proteins are homogeneously over-expressed in CLL patients.