Given that inhibition of GSK3β enhances NOTCH1 signaling, which has been shown to promote CLL cell survival [5–7], we performed MTS assay in CLL cells treated with SB216763 for 18 h (n = 8), to assess whether GSK3β directly modulates CLL cell viability. The gene discussed is NOTCH1; the disease is B-cell chronic lymphocytic leukemia.