[Adenanthin Induces Differentiation of Acute Promyelocytic Leukemia Cells by Targeting Peroxiredoxin III].

OBJECTIVE: To investigate the differentiation of acute promyelocytic leukemia (APL) cells induced by adenosine targeting Prx III. METHODS: HL-60 cells were divided into four groups: control group, all-trans retinoic acid (ATRA) group, adenanthin group and ATRA+adenanthin group. Cell morphologic changes were observed under optical microscope. The influence of adenanthin on the differentiation of HL-60 was observed by nitro blue tetrazolium chloride (NBT) test. Cell surface differentiation antigens CD11b expression was measured by flow cytometry. The protein expression of Prx III was detected by immunohistochemical assay. RESULTS: Adenanthin could induce the differentiation of HL-60 cells; the NBT reduction positive rate in ATRA+adenanthin group was significantly higher than that in ATRA group and adenanthin group (P＜0.05). The percentage of CD11b positive cells in ATRA+adenanthin group (43.62％±1.38％) was higher than that in adenanthin group (28.15％±1.78％), ATRA group (36.72％±1.33％) and control group (7.99％±1.78％) (P＜0. 05). The content of Prx Ⅲ protein in adenanthin group was significantly higher than that in control group and ATRA group (P＜0.05). CONCLUSION: Adenanthin and ATRA have a synergistic effect on the differentiation and maturation of HL-60 cells, and its mechanism may be related with regulation of Prx III expression.

A novel mutation in fibrillin-1 gene identified in a Chinese family with marfan syndrome.

Marfan syndrome (MFS) is an autosomal dominant inheritary disorder of the connective tissue. We report clinical features of a Chinese family with MFS and identify mutations in fibrillin-1 gene (FBN1). In this study, all three members of this family underwent complete ophthalmologic examinations. Two of the three members were diagnosed with MFS. Molecular genetic analysis was performed on the three members. All coding exons of FBN1 were amplified by polymerase chain reaction (PCR). The amplified products were sequenced and compared with a reference sequence in the database. Possible structural and functional changes of the protein induced by amino acids variance were predicted by bioinformatic analysis. A novel heterozygous mutation c.4504 T>A (p.C1502S) in exon 36 was identified in the two affected members, but not in the unaffected member. To our knowledge, this FBN1 mutation has not been reported beforein MFS or other patients.

Fasudil hydrochloride could promote axonal growth through inhibiting the activity of ROCK.

OBJECTIVE: This study aims to investigate the neuroprotective effect of Rho kinase inhibitor fasudil hydrochloride in ischemia/reperfusion injury N2a neuron. METHODS: In vitro, N2a cells induced by ischemia and ischemia-reperfusion were treated with fasudil hydrochloride, cell damage was analyzed by MTT. On the other hand, the cytoskeleton of N2a cells was scanned through immunofluorescence techniques by Confocal Laser Microscopy which stained with FITC-phalloidin for F-actin visualization. RESULTS: The activation of ROCK-II increased significantly in the damaged local during the following phase of ischemia/reperfusion injury. Ischemia induced a striking reorganization of actin cytoskeleton with a weakening of fluorescent intensity of the peripheral filament actin bands and formation of the long and thick stress fibers, but pretreatment of Fasudil hydrochloride could reversed the changes of ultra-structure on the cellular surface. MTT assay showed that Fasudil hydrochloride could prolong the survival time of the N2a cells after mimic ischemia-reperfusion for 24 h. CONCLUSIONS: The activation of ROCK-II has an exceptional hoist after ischemia/reperfusion injury, it is likely to induce the collapse of the growth cone through MLC-P. Fasudil hydrochloride could promote axonal growth on inhibitory of ROCK activity.

miR-200a inhibits tumor proliferation by targeting AP-2γ in neuroblastoma cells.

BACKGROUND: MicroRNA-200a (miR-200a) has been reported to regulate tumour progression in several tumours but little is known about its role in neuroblastoma. Our aim was to investigate the potential role and mechanism of miR-200a in neuroblastomas. MATERIALS AND METHODS: Expression levels of miR-200a in tissues were determined using RT-PCR. The effect of miR-200a and shAP-2γ on cell viability was evaluated using MTS assays, and target protein expression was determined using Western blotting and RT-PCR. Luciferase reporter plasmids were constructed to confirm direct targeting. RESULTS were reported as mean±S.E.M and differences were tested for significance using the 2-tailed Students t-test. RESULTS: We determined that miR-200a expression was significantly lower in neuroblastoma tumors than the adjacent non-cancer tissue. Over-expression of miR-200 are reduced cell viability in neuroblastoma cells and inhibited tumor growth in mouse xenografts. We identified AP-2γ as a novel target for miR-200a in neuroblastoma cells. Thus miR-200a targets the 3'UTR of AP-2γ and inhibits its mRNA and protein expression. Furthermore, our result showed that shRNA knockdown of AP-2γ in neuroblastoma cells results in significant inhibit of cell proliferation and tumor growth in vitro, supporting an oncogenic role of AP-2γ in neuroblastoma. CONCLUSIONS: Our study revealed that miR-200a is a candidate tumor suppressor in neuroblastoma, through direct targeting of AP-2γ. These findings re-enforce the proposal of AP-2γ as a therapeutic target in neuroblastoma.