OBJECTIVE To confirm the role played by AKT1 and AKT2 in the β- catenin/Tcf-4 signaling pathway in promoting malignant transfor- mation of glioma cells. METHODS LN229 cells were divided into five groups： a control g...OBJECTIVE To confirm the role played by AKT1 and AKT2 in the β- catenin/Tcf-4 signaling pathway in promoting malignant transfor- mation of glioma cells. METHODS LN229 cells were divided into five groups： a control group, acetone （ACE）group, acetylsalicylic acid （ASA; aspirin） group, ASA＋AKT1 plasmid group and ASA＋AKT2 plasmid group. Western blot and PCR were used to detect the expression of AKT1 and AKT2 after dealing with ASA and transferring AKTI/2 genes into LN229 cells. Cell proliferation was determined by flow cytometry, cell invasion was evaluated by transwell assay and cell apoptosis was detected with annexin V staining. The molecules regulating proliferation and invasion were examined by western blot analysis. RESULTS Aspirin down-regulates AKT1 and AKT2 expression by modulating β-cateninfrcf-4 activity. AKT1 and AKT2 can enhance cell proliferation and invasion by up-regulating the expression of cyclin-D and matrix metalloprotein-9 （MMP-9） in LN229 glioma cells. CONCLUSION AKT1 and AKT2 play an important role in the β- catenin/Tcf-4 signaling pathway promoting malignant transformation; AKT1 is more effective than AKT2. AKT1 and AKT2 may be potential targets for brain glioma therapy and an effective way to prevent metastasis of gliomas.展开更多
An invariant σ2（G） of a graph is defined as follows： σ2（G） ：= min{d（u） ＋ d（v）｜u, v ∈V（G）,uv ∈ E（G）,u ≠ v} is the minimum degree sum of nonadjacent vertices （when G is a complete graph, we define ...An invariant σ2（G） of a graph is defined as follows： σ2（G） ：= min{d（u） ＋ d（v）｜u, v ∈V（G）,uv ∈ E（G）,u ≠ v} is the minimum degree sum of nonadjacent vertices （when G is a complete graph, we define σ2（G） = ∞）. Let k, s be integers with k ≥ 2 and s ≥ 4, G be a graph of order n sufficiently large compared with s and k. We show that if σ2（G） ≥ n ＋ k- 1, then for any set of k independent vertices v1,..., vk, G has k vertex-disjoint cycles C1,..., Ck such that ｜Ci｜ ≤ s and vi ∈ V（Ci） for all 1 ≤ i ≤ k. The condition of degree sum σs（G） ≥ n ＋ k - 1 is sharp.展开更多
基金This work was supported by a grant from the National Natural Science Foundation of China （No. 30971132）.
文摘OBJECTIVE To confirm the role played by AKT1 and AKT2 in the β- catenin/Tcf-4 signaling pathway in promoting malignant transfor- mation of glioma cells. METHODS LN229 cells were divided into five groups： a control group, acetone （ACE）group, acetylsalicylic acid （ASA; aspirin） group, ASA＋AKT1 plasmid group and ASA＋AKT2 plasmid group. Western blot and PCR were used to detect the expression of AKT1 and AKT2 after dealing with ASA and transferring AKTI/2 genes into LN229 cells. Cell proliferation was determined by flow cytometry, cell invasion was evaluated by transwell assay and cell apoptosis was detected with annexin V staining. The molecules regulating proliferation and invasion were examined by western blot analysis. RESULTS Aspirin down-regulates AKT1 and AKT2 expression by modulating β-cateninfrcf-4 activity. AKT1 and AKT2 can enhance cell proliferation and invasion by up-regulating the expression of cyclin-D and matrix metalloprotein-9 （MMP-9） in LN229 glioma cells. CONCLUSION AKT1 and AKT2 play an important role in the β- catenin/Tcf-4 signaling pathway promoting malignant transformation; AKT1 is more effective than AKT2. AKT1 and AKT2 may be potential targets for brain glioma therapy and an effective way to prevent metastasis of gliomas.
基金Foundation item： the National Natural Science Foundation of China （No. 10626029）.
文摘An invariant σ2（G） of a graph is defined as follows： σ2（G） ：= min{d（u） ＋ d（v）｜u, v ∈V（G）,uv ∈ E（G）,u ≠ v} is the minimum degree sum of nonadjacent vertices （when G is a complete graph, we define σ2（G） = ∞）. Let k, s be integers with k ≥ 2 and s ≥ 4, G be a graph of order n sufficiently large compared with s and k. We show that if σ2（G） ≥ n ＋ k- 1, then for any set of k independent vertices v1,..., vk, G has k vertex-disjoint cycles C1,..., Ck such that ｜Ci｜ ≤ s and vi ∈ V（Ci） for all 1 ≤ i ≤ k. The condition of degree sum σs（G） ≥ n ＋ k - 1 is sharp.
