Chronic lymphocytic leukemia (CLL) B cells are hyporesponsive or refractory to mitogens and growth factors in vitro. This study examined whether transforming growth factor beta (TGF-beta), a potent inhibitor of lymphocyte proliferation may play a role in the growth regulation of CLL B cells. CLL B cells from all donors treated expressed detectable TGF-beta 1 mRNA. In vitro release of TGF-beta b...

B-cell chronic lymphocytic leukemia (CLL), the most common leukemia in the Western world. CLL occurs in two forms, aggressive and indolent. Aggressive CLL is characterized by high ZAP-70 expression and unmutated IgH V(H); indolent CLL shows low ZAP-70 expression and mutated IgH V(H). We recently found that miR-29 is up-regulated in indolent human B-CLL, compared to aggressive B-CLL and normal C...

B-cell chronic lymphocytic leukemia (B-CLL) cells accumulate in vivo in the G0/G1 phase of the cell cycle, suggesting that their malignant expansion is due, at least in part, to a delay in cell death. However, the cellular or molecular factors responsible for a delay in B-CLL cell death are unknown. B-CLL cells do express receptors for interferon-alpha (IFN-alpha) and IFN-gamma, and activation ...

Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of clonally derived mature CD5high B cells; however, the cellular origin of CLL is still unknown. Patients with CLL also harbor variable numbers of CD5low B cells, but the clonal relationship of these cells to the bulk disease is unknown and can have important implications for monitoring, treating, and understanding the bio...

Natural products isolated from plant sources are well known for their pharmacological potential in diversity of disease treatments such as inflammatory or cancer conditions. Mango (Mangifera indica L.) and Juglans regia are thought to be rich of functional phytochemicals. To elucidate the anticancer activity of Juglans regia (JR) and Mangifera indica L (MI) aqueous extract were investigated on ...

Natural products isolated from plant sources are well known for their pharmacological potential in diversity of disease treatments such as inflammatory or cancer conditions. Mango (Mangifera indica L.) and Juglans regia are thought to be rich of functional phytochemicals. To elucidate the anticancer activity of Juglans regia (JR) and Mangifera indica L (MI) aqueous extract were investigated on ...

Glutathione (GSH) content may be the major determinant of a cell's sensitivity to cytotoxic alkylating agents. In the present study, the GSH concentration was determined in lymphocytes isolated from the blood of normal subjects and patients with chronic lymphocytic leukemia (CLL). Comparable levels were found in both types of cells. Incubation for 20 hours led to a decrease in GSH to 51% of bas...

Although spontaneous remissions may rarely occur in B-cell chronic lymphocytic leukemia (B-CLL), T cells do generally not develop a clinically significant response against B-CLL cells. Because this T-cell anergy against B-CLL cells may be caused by the inability of B-CLL cells to present tumor-antigens efficiently, we examined the possibility of upregulating critical costimulatory (B7-1 and B7-...

Type 4 cyclic adenosine monophosphate (cAMP) phosphodiesterase (PDE4) inhibitors and other agents that raise intracellular cAMP levels induce apoptosis in B-cell chronic lymphocytic leukemia (B-CLL) but not in T-CLL or peripheral blood T cells. Two principal effector proteins for cAMP are protein kinase A (PKA) and EPAC (exchange protein directly activated by cAMP), a Rap guanosine 5'-diphospha...