IL27 and B-cell chronic lymphocytic leukemia: Levels of soluble mediators are known to be disturbed in oncology patients depending on whether they favor or hinder tumor growth, increasing or decreasing respectively when compared to healthy individuals.7 Interestingly, our data8 uncovered a significant and consistent decrease in IL-27 serum levels as the disease progresses in both pre-clinical and patient CLL samples, suggesting an anti-tumor effect of IL-27 in the development and progression of this malignancy.