Regulatory T-cells in chronic lymphocytic leukemia: actor or innocent bystander?

Regulatory T (Treg) cells are now under extensive investigation in chronic lymphocytic leukemia (CLL). This small subset of T-cells has been, in fact, considered to be involved in the pathogenesis and progression of CLL. However, whether Treg dysregulation in CLL plays a key role or it rather represents a simple epiphenomenon is still matter of debate. In the former case, Treg cells could be appealing for targeting therapies. Finally, Treg cells have also been proposed as a prognostic indicator of the disease clinical course.

Active caspase-3 detection to evaluate apoptosis induced by Verbena officinalis essential oil and citral in chronic lymphocytic leukaemia cells

Verbena officinalis L., Verbenaceae, commonly known as vervain, is a plant widely used in medicine. Despite of its widespread use in different traditional practices, the mechanisms of pharmacological actions of the plant and its volatile oil are still unclear. We evaluated the pro-apoptotic activity of V. officinalis essential oil and of its main component, citral, on lymphocytes collected from ten patients with chronic lymphocytic leukaemia (CLL), a disease in which a faulty apoptotic mechanism is still retained one of the primary pathogenic events, by adding to treated mononuclear cells, annexin-V, propidium iodide, and CD19. Apoptosis was also evaluated using anti-active-caspase-3 monoclonal antibody after permeabilization of the cells. Both V. officinalis essential oil and citral were found able to induce apoptosis in CLL cells and to activate caspase-3, which is considered the way by means they active apoptosis in B neoplastic cells. This data further support evidences that indicate natural compounds as possible lead structure to develop new therapeutic agents for CLL.

Antiproliferative effects of tree-of-heaven (Ailanthus altissima Swingle).

Tree-of-heaven (Ailanthus altissima Swingle) was evaluated for its cytotoxic and antiproliferative activities by a bioassay-oriented study. Cytotoxicity observed in HeLa cells was time-dependent; the treatment with 10 microg/mL of the root chloroform extract reduced cell viability by 56% at 24 h and 29% at 48 h of exposure, whereas no effect was recorded in the controls. Significant effects were observed also for chromatographic fractions and the pure isolated alkaloid 1-methoxy-canthin-6-one. After 72 h of incubation cell viability was less than 10% for all treatments. A possible apoptotic effect was evaluated by monitoring the presence of hypodiploid elements in HeLa cells as well as in SAOS, U87MG and U-937 tumor cell lines. The cells incubated for different times with the active extract, fraction and pure alkaloid isolated from A. altissima showed a remarkable increase in the apoptosis.