BACKGROUNDMenin is a ubiquitously expressed protein encoded by the multiple endocrine neoplasia type 1 (MEN1) gene. Besides its importance in endocrine organs, menin has been shown to interact with the mixed lineage leukemia (MLL) protein, a histone H3 lysine 4 methyltransferase, and plays a critical role in hematopoiesis and leukemogenesis. Previous studies have shown that menin promotes transforming growth factor beta (TGF-β) signaling in endocrine cells. However, little is known regarding the impact of TGF-β pathway on menin in hematopoietic system. Here, with leukemia cell lines generated from conditional MEN1 or TGF-β receptor (TβRII) knockout mouse models, we investigated the possible cross-talk of these two pathways in leukemia cells.

METHODSMEN1 or TβRII conditional knockout mice were bred and the bone marrow cells were transduced with retroviruses expressing oncogeneic MLL-AF9 (a mixed lineage leukemia fusion protein) to generate two leukemia cell lines. Cell proliferation assays were performed to investigate the effect of TGF-β treatment on MLL-AF9 transformed leukemia cells with/without MEN1 or TβRII excision. Menin protein was detected with Western blotting and mRNA levels of cell proliferation-related genes Cyclin A(2) and Cyclin E(2) were examined with real-time RT-PCR for each treated sample. In vivo effect of TGF-β signal on menin expression was also investigated in mouse liver tissue after TβRII excision.

RESULTSTGF-β not only inhibited the proliferation of wild type MLL-AF9 transformed mouse bone marrow cells, but also up-regulated menin expression in these cells. Moreover, TGF-β failed to further inhibit the proliferation of Men1-null cells as compared to Men1-expressing control cells. Furthermore, excision of TβRII, a vital component in TGF-β signaling pathway, down-regulated menin expression in MLL-AF9 transformed mouse bone marrow cells. In vivo data also confirmed that menin expression was decreased in liver samples of conditional TβRII knockout mice after TβRII excision.

CONCLUSIONThese results provided the first piece of evidence of cross-talk between menin and TGF-β signaling pathways in regulating proliferation of leukemia cells, suggesting that manipulating the cross-talk of the two pathways may lead to a novel therapy for leukemia.

Animals ; Blotting, Western ; Cells, Cultured ; Humans ; Leukemia ; metabolism ; Mice ; Mice, Knockout ; Multiple Endocrine Neoplasia Type 1 ; genetics ; metabolism ; Oncogene Proteins, Fusion ; genetics ; metabolism ; Protein-Serine-Threonine Kinases ; genetics ; metabolism ; Real-Time Polymerase Chain Reaction ; Receptors, Transforming Growth Factor beta ; genetics ; metabolism ; Transforming Growth Factor beta ; genetics ; metabolism

Objective To investigate the visual acuity condition of preschool children in Yangpu District of Shanghai, providing the basis for formulation of corresponding intervention measures for myopia. Methods The inspection equipment was the international standard logarithmic E-word visual acuity chart, and the Canon RK-F1 automatic computer optometry instrument.By using cross-sectional study and random cluster sampling method, a total of 1 415 preschool children in 5 kindergartens in Yangpu District were selected according to their ages and genders, and their visual acuity and refractive parameters were examined with the result being statistically analyzed. Results In preschool children of Yangpu District, their envisage rate was 80.4%, myopia rate 16.7% and hyperopia rate 2.9%.There was no significant difference in the incidence rate of envisage, myopia and hyperopia between different age groups (χ²=3.419, P=0.755) and different genders (χ²=2.433, P=0.296).The rate of poor vision for preschool children in Yangpu was 10.5%.There was a statistically significant difference in the rate of poor vision between different age groups (χ²=9.637, P=0.022) and different genders (χ²=4.191, P=0.041). Conclusion The visual acuity rate and myopia rate in preschool children are not optimistic and need further screening and early intervention.

Objective To study the effect of the 18kDa translocator protein (TSPO) on U251cells of human glioma. Methods U251 cell line was cultured in vitro conventionally.The specific ligand ofTSPO,pk11195,was used in 5 experimental groups respectively with concentrations of 100,50,25,12.5 and 6.25 μmol/L,in comparison with a control group.MTr colorimetry and trypan blue staining were used to detect cell proliferation.Hoechst33342 staining and flow cytometry were applied to detect cell apoptosis. Western blotting and immumofluorescence method were used to detect the expression level of TSPO. DCFH-DA probe and GSH kit were used to respectively detect the level of reactive oxygen species (ROS) and GSH level in cells.Jc-1 staining was applied to detect the mitochondrial membrane potential.Luciferase enzyme was used to detect the quantity of ATP in cells. Results MTT showed the survival of U251 cells was significantly higher in the groups of 50 and 25 μmol/L pk11195than in the control group (P＜0.05). Trypan blue staining showed the cell death rate was significantlylower in the group of 50 μmol/L pk11195 than in the control group (P＜0.05).The apoptosis rate,TSPO expression,ROS and GSH levels decreased significantly in the groups of 6.25 and 50 μmol/L pk11195,compared with the control group; the apoptosis rate was significantly lower in the group of 50 μmol/Lpk11195 than in the group of 6.25 μmol/L pk11195 (P＜0.05).The cell membrane potential and ATP quantity were significantly higher in the groups of 6.25 and 50 μmol/L pk11195 than in the control group,and those in the group of 50 μmol/L pk11195 were significantly higher than in the group of 6.25 μmol/Lpk11195 (P＜0.05). Conclusion TSPO may promote apoptosis of U251 cells in human glioma and inhibit proliferation of glioma cells,functioning similarly as a cancer suppressor gene.

Polycystic ovary syndrome (PCOS) is a heterogeneous endocrine disorder, which is characterized by hyperandrogenism, insulin resistance and chronic anovulation, and has become a serious threat to the health of adolescents and women of childbearing age.At present,lowering androgen, improving insulin resistance and inducing ovulation are the main methods adopted by doctors to treat the disease, but the adverse reactions of the western medicine and the long-term treatment are hard to be accepted by the patients. PCOS treated by traditional Chinese medicine has achieved a certain effect in recent years.Traditional Chinese medicine is relatively safe and has more effect in many links and targets in improving the symptom of endocrine and metabolic disorder in patients with PCOS. This paper expounds the traditional Chinese medicine pathogenesis of PCOS through clinical and experimental aspects of the literature research：correcting endocrine hormone disorder,the effects of the expression of gene and regulatory factors,improving insulin resistance,correcting lipid metabolic disorder,improving the pregnancy outcome and improving ovarian morphology to summarize the treatment of traditional Chinese medicine in PCOS research results in recent years.