STAT3 and B-cell chronic lymphocytic leukemia: The pro-apoptotic effect of cucurbitacin I was seen in B-leukaemia cells and primary chronic lymphocytic leukaemia, where the inhibition of phosphorylated STAT3 led to the downregulation of an anti-apoptotic gene, XIAP, and the cell cycle regulatory gene, CDC2 and upregulated DR4 [106].