No role for cerebrospinal fluid myelin basic protein levels in patients treated for childhood acute lymphoblastic leukemia

Combinational treatment of 5-fluorouracil and casticin induces apoptosis in mouse leukemia WEHI-3 cells in vitro

Leukemia is one of the major diseases causing cancer-related deaths in the young population, and its cure rate is unsatisfying with side effects on patients. Fluorouracil (5-FU) is currently used as an anticancer drug for leukemia patients. Casticin, a natural polymethoxyflavone, exerts anticancer activity against many human cancer cell lines in vitro, but no other reports show 5-FU combined with casticin increased the mouse leukemia cell apoptosis in vitro. Herein, the antileukemia activity of 5-FU combined with casticin in WEHI-3 mouse leukemia cells was investigated in vitro. Treatment of two-drug combination had a higher decrease in cell viability and a higher increase in apoptotic cell death, the level of DNA condensation, and the length of comet tail than that of 5-FU or casticin treatment alone in WEHI-3 cells. In addition, the two-drug combination has a greater production rate of reactive oxygen species but a lower level of Ca²⁺ release and mitochondrial membrane potential (ΔΨ_m ) than that of 5-FU alone. Combined drugs also induced higher caspase-3 and caspase-8 activities than that of casticin alone and higher caspase-9 activity than that of 5-FU or casticin alone at 48 hours treatment. Furthermore, 5-FU combined with casticin has a higher expression of Cu/Zn superoxide dismutase (SOD [Cu/Zn]) and lower catalase than that of 5-FU or casticin treatment alone. The combined treatment has higher levels of Bax, Endo G, and cytochrome C of proapoptotic proteins than that of casticin alone and induced lower levels of B-cell lymphoma 2 (BCL-2) and BCL-X of antiapoptotic proteins than that of 5-FU or casticin only. Furthermore, the combined treatment had a higher expression of cleaved poly (ADP-ribose) polymerase (PARP) than that of casticin only. Based on these findings, we may suggest that 5-FU combined with casticin treatment increased apoptotic cell death in WEHI-3 mouse leukemia cells that may undergo mitochondria and caspases signaling pathways in vitro.

Ouabain promotes immune responses in WEHI-3 cells to generate leukemia mice through enhancing phagocytosis and natural killer cell activities in vivo

Ouabain, a cardiotonic steroid, was used for the treatment of heart failure and atrial fibrillation and induces cancer cell apoptosis in many human cancer cells including human leukemia cells. However, there are no reports to show the effects on immune responses in a leukemia mouse model. In this study, WEHI-3 cell generated leukemia mice were developed and treated by oral ouabain at 0, 0.75, 1.5, and 3 mg/kg for 15 days. Results indicated that ouabain did not affect body appearance, but decreased liver and spleen weights, B- and T-cell proliferation at all three doses treatment and increased CD19 cells at 3.0 mg/kg treatment, decreased CD3, CD11b, and Mac-3 cells levels compared with positive control. Furthermore, ouabain increased the macrophage phagocytosis from peripheral blood mononuclear cell and peritoneal cavity at all three doses treatment and increased NK cell activities. Ouabain restored GOT, GPT and LDH levels in WEHI-3 leukemia mice in vivo.

Maslinic Acid Enhances Immune Responses in Leukemic Mice Through Macrophage Phagocytosis and Natural Killer Cell Activities In Vivo

BACKGROUND/AIM

Maslinic acid (MA), a pentacyclic triterpene extracted from wax-like coatings of olives, has been shown to reduce cancer cell number through induction of autophagy and apoptosis in many human cancer cells including human leukemia HL-60 cells. In the present study, we investigated whether or not MA affects immune responses in a leukemia mouse model.

MATERIALS AND METHODS

WEHI-3 cells were intraperitonealIy (i.p.) injected into normal BALB/c mice to develop leukemia. Mice were then treated by i.p. injection with MA at different doses (0, 8, 16 and 32 mg/kg) for 2 weeks. After treatment, all animals were weighed and blood, liver and spleen tissues were weighed. Blood or spleen both were used for determination of cell markers or phagocytosis, natural killer (NK) cell activities and T- and B-cell proliferation, respectively, by using a flow cytometric assay.

RESULTS

MA did not significantly affect body, liver, and spleen weights. However, MA increased markers of T-cells (at 16 mg/kg treatment) and monocytes (at 32 mg/kg treatment), but reduced B-cell markers (at 8 mg/kg treatment); MA did not significantly affect cell marker of macrophages. Furthermore, MA increased phagocytosis by macrophages from peripheral blood mononuclear cells and peritoneal cavity at 32 mg/kg treatment and increased NK cell activity at target cell:splenocyte ratio of 25:1 but did not affect B- and T-cell proliferation.

CONCLUSION

MA increased immune responses by enhancing macrophage phagocytosis and NK cell activities in leukemic mice.

Bufalin Enhances Immune Responses in Leukemic Mice Through Enhancing Phagocytosis of Macrophage In Vivo

BACKGROUND/AIM

Bufalin, bufadienolide present in Chan Su, has been shown to induce cancer cell apoptosis in many human cancer cells, including human leukemia cells, but its effects on immune responses are unknown.

MATERIALS AND METHODS

This study investigated whether bufalin affected immune responses of mice with WEHI-3 cell-generated leukemia in vivo. BALB/c mice were intraperitoneally injected with WEHI-3 cells to develop leukemia and then were treated with oral treatment with bufalin at different doses (0, 0.1, 0.2 and 0.4 mg/kg) for 2 weeks. At the end of treatment, all mice were weighted and blood was collected; liver and spleen tissues were collected for cell marker, phagocytosis, natural killer (NK) cell activity and T- and B-cell proliferation measurements by using flow cytometric assays.

RESULTS

When compared with the leukemia control group, bufalin increased the body weight, but reduced liver and spleen weights, and reduced CD3, CD16 and Mac-3 cell markers at 0.4 mg/kg treatment and increased CD11b marker at 0.1 and 0.2 mg/kg treatment. Furthermore, bufalin at 0.4 mg/kg increased phagocytosis by macrophages isolated from peripheral blood mononuclear cells and at 0.1 mg/kg by those from the peritoneal cavity. Bufalin (0.2 and 0.4 mg/kg) increased NK cell cytotoxic activity at effector:target ratio of 50:1. Bufalin increased B-cell proliferation at 0.1 and 0.2 mg/kg treatment but only increased T-cell proliferation at 0.1 mg/kg. Bufalin increased glutamate oxaloacetate transaminase level at all dose treatments, increased glutamic pyruvic transaminase level only at 0.1 mg/kg treatment, but reduced the level of lactate dehydrogenase at all dose levels in mice with WEHI-3 cell-induced leukemia in vivo.

CONCLUSION

Bufalin increased immune responses by enhancing phagocytosis in mice with leukemia mice.