The aim of this study was to investigate the in vitro effect of interleukin-24 (IL-24) on apoptosis of bone marrow mononuclear cells (BMMNC) in children with acute leukemia. Every group of acute lymphocytic leukemia (ALL) and acute myeloid leukemia (ANLL) had 20 children who did not receive any therapy. The bone marrow was taken from patients and controls, the MNC were isolated from bone marrow, DNA was detected by glucose electrophoresis. Apoptosis of BMMNC was assayed by flow cytometry with propidium iodine staining. RT-PCR was used to detect the expression level of bcl-2, caspase-3 mRNA, and to analyze the effect of IL-24 on them. The results showed that the IL-24 induced apoptosis of BMMNC in children with acute leukemia. After acute leukemia BMMNC were exposed to IL-24 for 48 hours, DNA ladder fragment appeared, and the apoptotic rate of the group treated with IL-24 of 50 ng/ml was obviously higher than that of the control group (0 ng/ml). IL-24 decreased the bcl-2 mRNA expression level, enhanced caspase-3 mRNA expression level of BMMNC from AL patients. It is concluded that the IL-24 can induce apoptosis of AL BMMNC in vitro, which may be due to decreasing of bcl-2 mRNA level and enhancing of caspase-3 mRNA level.
Acute Disease ; Adolescent ; Apoptosis ; drug effects ; Bone Marrow Cells ; cytology ; drug effects ; Caspase 3 ; metabolism ; Child ; Child, Preschool ; Female ; Humans ; Interleukins ; pharmacology ; Leukemia ; pathology ; Male ; Proto-Oncogene Proteins c-bcl-2 ; metabolism

OBJECTIVESTo identify whether Epstein-Barr virus (EBV) encoded latent membrane protein 1 (LMP1) can induce tumor necrosis factor receptor-associated factor 1 (TRAF1) expression and promote its anti-apoptosis activity via the NF-kappaB signaling pathway, and assess that LMP1 suppresses apoptosis in nasopharyngeal carcinoma (NPC).

METHODSA stable transfected cell line HNE2-LMP1 was established by introducing LMP1 cDNA into HNE2 cells. Transactivation of TRAF1 was determined by luciferase reporter assay, while expression of TRAF1 mRNA was detected by RT-PCR and expression of TRAF1 protein and caspase 3 by Western blot analysis. Apoptosis activity was observed through fluorescence staining.

RESULTSLMP1 induced TRAF1 expression in NPC cells and caused a decrease in apoptosis. This induction could be blocked by antisense LMP1. Moreover, LMP1-mediated induction of a TRAF1 promoter-driven reporter gene was significantly impaired when the kappaB site kappaB1 or kappaB5 was disrupted, whereas mutation of kappaB3 had only a minor effect on LMP1 dependent up-regulation of the reporter gene.

CONCLUSIONLMP1 induces TRAF1 expression and promotes its anti-apoptosis activity via the NF-kappaB signaling pathway, which may be one of the mechanisms that LMP1 uses to suppress apoptosis in NPC cells.

Apoptosis ; physiology ; Humans ; NF-kappa B ; physiology ; Nasopharyngeal Neoplasms ; physiopathology ; Protein Biosynthesis ; Signal Transduction ; physiology ; TNF Receptor-Associated Factor 1 ; Tumor Cells, Cultured ; Viral Matrix Proteins ; physiology

Aim To establish human U87-MG glioma model in nude mice brain and to observe the characteristics of the tumor growth. Methods Human U87-MG glioma cells were cultured in vitro. 5 μL of cell suspension containing 3.0 ×1010·L-1, 4.0×1010·L-1and 5.0×1010·L-1respectively was inocula-ted into the right caudate nucleus of 18 male nude mice brain un-der the guidance of stereotaxic apparatus, separately, whereas another 6 nude mice as the control group, were inoculated into the same volume of Hanks solution. The moving and survival state of rats with gliomas were observed. The examinations of the tumors formation, volumes, metastasis and histopathology were performed and the obtained brain samples were stained with HE and immunohistochemistry. Results All the tested rats of dif-ferent inoculation doses developed brain tumors without extracra-nial metastasis. The mean survival time of three groups was (46.50 ± 3.27) d,(38.50 ± 3.28) d and (30.67 ± 3.51) d,respectively. The tumors showed the similar morphological fea-tures and immunophenotype to human glioma. There was positive expression of GFAP and S-100 in the tumors. Conclusions The orthotopic implantation model of human U87-MG glioma, by in-oculating quantitative U87-MG cells stereotaxically into the brains of the nude mice, is successfully established with 100 yield of intracranial tumor and no extracranial growth extension. It resembles the histopathological and morphological features of human glioma,which can be used as a reliable animal model for the study of the tumorigenesis, pathogenesis, biological charac-teristics and therapy of glioma.